
Cough and bronchoconstriction mediated by capsaicin-sensitive sensory neurons in the guinea-pig.
Forsberg K,Karlsson J A,Theodorsson E,Lundberg J M,Persson C G
Pulmonary pharmacology
Neural pathways involved in cough and reflex bronchoconstriction and the effects of drugs on these airway reflexes have been studied in unanaesthetised guinea-pigs exposed to aerosols of citric acid (0.13-0.78 M), capsaicin (30 microM), nicotine (9.2 mM) and histamine (0.9 mM). The number of coughs was counted during the first 3 min of exposure and the time to onset of signs of dyspnea, as an indication of bronchoconstriction, was measured. Citric acid produced bronchoconstriction and dose-dependently increased the number of coughs. Capsaicin produced both cough and bronchoconstriction. Nicotine mainly produced cough and histamine bronchoconstriction. Pretreatment of adult guinea-pigs with capsaicin (50 mg kg-1 s.c.) produced a long-lasting (greater than or equal to 10 weeks) depletion of substance P- and calcitonin gene related peptide-like immunoreactivities in the sensory nerves of the larynx, tracheobronchial tree and lung. In capsaicin-treated animals, citric acid (0.39 M) and capsaicin (30 microM) caused neither cough nor bronchoconstriction. Nicotine (9.2 mM) and mechanical stimulation still produced cough, and histamine (0.9 mM) bronchoconstriction. It is concluded that in guinea-pigs both capsaicin-sensitive (probably C-fibre endings) and capsaicin-resistant (probably rapidly adapting stretch receptors) afferent neurons may be involved in cough and reflex bronchoconstriction.
10.1016/0952-0600(88)90008-7
Automated algorithm for Wet/Dry cough sounds classification.
Swarnkar V,Abeyratne U R,Amrulloh Yusuf A,Chang Anne
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
Cough is the most common symptom of several respiratory diseases. It is a defense mechanism of the body to clear the respiratory tract from foreign materials inhaled accidentally or produced internally by infections. The identification of wet and dry cough is an important clinical finding, aiding in the differential diagnosis. Wet coughs are more likely to be associated with bacterial infections. At present, the wet/dry decision is based on the subjective judgment of a physician, during a typical consultation session. It is not available for long term monitoring or in the assessment of treatment efficacy. In this paper we address these issues and develop fully automated technology to classify cough into 'Wet' and 'Dry' categories. We propose novel features and a Logistic regression-based model for the classification of coughs into wet/dry classes. The performance of the method was evaluated on a clinical database of pediatric and adult coughs recorded using a bed-side non-contact microphone. The sensitivity and specificity of the classification were obtained as 79±9% and 72.7±8.7% respectively. These indicate the potential of the method as a useful clinical tool for cough monitoring, especially at home settings.
10.1109/EMBC.2012.6346632
Assessment of radio(chemo)therapy-related dysphagia in head and neck cancer patients based on cough-related acoustic features: a prospective phase II national clinical trial (ACCOUGH-P/A trial).
Trials
BACKGROUND:Radiation-associated dysphagia is defined as impaired swallowing efficiency/safety following (chemo)radiotherapy in head and neck cancer patients. In a dysphagia framework, impaired coughing may lead to lung aspiration and fatal lung infection. Although cough efficacy is a predictor of the risk of aspiration, cough investigation is minimal in patients with radiation-associated dysphagia. Because cough is a transient signal, existing software for speech analysis are not appropriate. The goal of our project is to develop an assessment method using acoustic features related to voluntary and reflexive coughs as biomarkers of the risk of penetration/aspiration in patients with radiation-associated dysphagia. METHODS:Healthy subjects and head and neck cancer patients with and without dysphagia will produce voluntary coughs, throat clearings and reflexive coughs. Recordings will be made using an acoustic microphone and a throat microphone. The recorded signals will be manually segmented and subsequently analysed with a software under development. Automatic final segmentation enables to measure cough duration. The first method of analysis includes temporal features: the amplitude contour, the sample entropy and the kurtosis. These features report respectively the strength, the unpredictability (turbulence noise due to the air jet) and the impulsive quality (burst) of the signal. The second method of analysis consists of a spectral decomposition of the relative cough signal energy into several frequency bands (0-400 Hz, 400-800 Hz, 800-1600 Hz, 1600-3200 Hz, > 3200 Hz). The primary outcome of this exploratory research project is the identification of a set of descriptive acoustic cough features in healthy subjects as reference data (ACCOUGH). The secondary outcome of this research in head and neck cancer patients with radiation-associated dysphagia includes the identification of (1) a set of descriptive acoustic cough features as biomarkers of penetration-aspiration (ACCOUGH-P/A), (2) swallowing scores, (3) voice features and (4) aerodynamic cough features. DISCUSSION:This study is expected to develop methods of acoustic cough analysis to enhance the assessment of radiation-associated dysphagia in head and neck cancer patients following (chemo)radiation. TRIAL REGISTRATION:International Standard Randomized Controlled Trials Number (ISRCTN) registry ISRCTN16540497. Accepted on 23 June 2023.
10.1186/s13063-023-07660-y
Cough-enhanced mucus clearance in the normal lung.
Bennett W D,Foster W M,Chapman W F
Journal of applied physiology (Bethesda, Md. : 1985)
We studied the effectiveness of cough for clearing mucus in 12 nonsmoking subjects with normal lung function. On 2 separate study days, each subject breathed 6-microns Mass Median Aerodynamic Diameter 99mTc-labeled iron oxide particles under controlled breathing conditions while they were seated in front of a gamma camera. Retention (R) of lung activity was measured over the initial 2 h and again at 24 h after particle inhalation. On the control day the subject sat quietly in front of the camera, while on the cough day each subject performed 60 controlled coughs during the 1st h of retention measurements. By paired analysis, retentions at both 1 and 2 h (R1 and R2, respectively) for the cough measurements were significantly less than control (mean control R1 = 85% vs. mean cough R1 = 72%, P less than 0.002; mean control R2 = 75% vs. mean cough R2 = 65%, P less than 0.02). Retention at 24 h (R24) was not significantly different between cough and control measurements (mean cough R24 = 35% and mean control R24 = 32%). Thus coughing increased the rate at which the radiolabeled particles were cleared from the bronchial airways in these individuals. Follow-up experiments with subjects performing rapid inhalations rather than cough showed similar enhanced particle clearance to that seen with cough. These results suggest that the observed enhancement of mucus clearance by cough (and rapid inhalation) in the normal lung may be due to a stimulation of the mucociliary apparatus rather than via a two-phase gas-liquid flow mechanism.
10.1152/jappl.1990.69.5.1670
Capsaicin inhalation test for identification of sensory hyperreactivity.
Johansson A,Löwhagen O,Millqvist E,Bende M
Respiratory medicine
BACKGROUND:Patients with upper and lower airway symptoms and with pronounced sensitivity to chemical odours, such as perfumes, flower scents and tobacco smoke, have been suggested to have sensory hyperreactivity (SHR). The symptoms have been difficult to identify with physiological measurements and the effects of various medications are doubtful. However, these patients have been found to be more sensitive to inhalation of capsaicin than healthy people. The aim of this study was to establish limit values with the capsaicin inhalation test in patients with SHR. METHODS:Ninety-five consecutive patients with upper and lower airway problems, who were admitted for allergy testing, underwent a capsaicin inhalation test with three different concentrations. The number of coughs was registered during each challenge. Score systems were used for symptoms and influence on social life of sensitivity to odours. In relation to scored symptoms, the patients were grouped as SHR or not, and compared with 73 healthy controls. RESULTS:All patients and controls coughed on capsaicin in a dose-dependent manner. Symptom score of odour sensitivity in patients was positively correlated to the response of the test. Out of 95 patients, 15 (16%) were scored to SHR. Patients with SHR reacted more to the capsaicin inhalation test than the other patients and the healthy controls. The limit values for a positive capsaicin inhalation test for the SHR were determined to be 10, 35 and 55 coughs at 0.4, 2.0 and 10 microM capsaicin, respectively. CONCLUSION:The capsaicin inhalation test well reflects the degree of airway sensitivity to chemicals and to what extent the social life is influenced. The cut-off values of the test can distinguish patients with pronounced sensitivity to odours.
Bronchoconstriction-triggered cough in conscious guinea pigs.
Ohkura Noriyuki,Fujimura Masaki,Hara Johsuke,Ohsawa Masahiro,Kamei Junzo,Nakao Shinji
Experimental lung research
The aim of the present study was to investigate the relation between bronchoconstriction and cough induced by methacholine (Mch) inhalation and to elucidate the role of C-fibers and rapidly adapting irritant receptors (RARs) in these reactions in conscious guinea pigs. The authors measured enhanced pause (Penh) as an index of bronchoconstriction and also measured the number of coughs induced by Mch inhalation in conscious guinea pigs. The authors also examined the effects of pretreatment with procaterol, capsaicin desensitization and moguisteine on these responses. There was a significant positive correlation between the increase in Penh and the number of coughs induced by Mch inhalation. Procaterol (0.1 mg/kg, intraperitoneal [i.p.]) completely abolished both the Mch-induced increase in Penh and cough. Capsaicin desensitization had no effect on Penh or the number of coughs. Moguisteine (0.02, 0.2, or 2 mg/kg, i.p.) dose-dependently inhibited the number of coughs but not the increase in Penh induced by Mch inhalation. Bronchoconstriction causes cough via RARs, but not C-fibers. Neither RARs nor C-fibers are involved in Mch-induced bronchoconstriction itself.
10.1080/01902140802668831
Role of cyclin-dependent kinase 5 in capsaicin-induced cough.
Kamei Junzo,Hayashi Shun-suke,Takahashi Yoshiki,Nozaki Chihiro
European journal of pharmacology
The role of cyclin-dependent kinase 5 (Cdk5) in the capsaicin-induced cough reflex was examined in mice. Pretreatment with inhaled roscovitine, a selective Cdk5 inhibitor, at concentrations of 0.3 to 3 mM inhibited the number of capsaicin-induced coughs in a concentration-dependent manner. Pretreatment with inhaled roscovitine, at a concentration of 3 mM also slightly but significantly inhibited the number of citric acid-induced coughs. The number of capsaicin-induced coughs was significantly reduced when C-fibers were desensitized by the pretreatment with capsaicin. The number of citric acid-induced coughs was slightly but significantly reduced in capsaicin-pretreated mice as compared with that in naive mice. Although the inhalation of roscovitine at a concentration of 3 mM significantly reduced the number of citric acid-induced coughs in naive mice to the level observed in capsaicin-pretreated mice, roscovitine had no effect on the number of citric acid-induced coughs in capsaicin-pretreated mice. These results suggest that Cdk5-dependent factors are involved in C-fiber-mediated cough signaling.
10.1016/j.ejphar.2007.03.036
Coughs cause systemic blood flow.
Cary J M,Krugmeier R,Newman B,Ross B,Butler J
Thorax
Although it is known that rhythmic coughing can preserve consciousness during ventricular fibrillation, the arterial pressure transients which result have not yet been shown to reflect forward blood flow in man. The effectiveness of cough in causing forward flow in eight normal volunteers with bradycardia was studied. They coughed between cardiac cycles, using an audio and visual display of the electrocardiogram. The force of the cough was varied and measured with an oesophageal balloon. Blood flow was recorded with a Döppler velocity probe over the radial artery and a finger or ear photoplethysmograph. Motion artefact on the Döppler record due to coughing was excluded by transiently obstructing the brachial artery. We compared the areas under 5-10 consecutive Döppler and photoplethysmograph pulse flow tracings due to the cough and heart beat with those due to the immediately preceding heart beat alone. They were significantly increased. This augmentation was greater in those flow pulses accompanied by a more vigorous cough. It is concluded that coughing is associated with an effort dependent forward flow pulse in the arterial circulation.
10.1136/thx.39.3.192
Flow dynamics and characterization of a cough.
Gupta J K,Lin C-H,Chen Q
Indoor air
UNLABELLED:Airborne disease transmission has always been a topic of wide interests in various fields for decades. Cough is found to be one of the prime sources of airborne diseases as it has high velocity and large quantity of droplets. To understand and characterize the flow dynamics of a cough can help to control the airborne disease transmission. This study has measured flow dynamics of coughs with human subjects. The flow rate variation of a cough with time can be represented as a combination of gamma-probability-distribution functions. The variables needed to define the gamma-probability-distribution functions can be represented by some medical parameters. A robust multiple linear regression analysis indicated that these medical parameters can be obtained from the physiological details of a person. However, the jet direction and mouth opening area during a cough seemed not related to the physiological parameters of the human subjects. Combining the flow characteristics reported in this study with appropriate virus and droplet distribution information, the infectious source strength by coughing can be evaluated. PRACTICAL IMPLICATIONS:There is a clear need for the scientific community to accurately predict and control the transmission of airborne diseases. Transportation of airborne viruses is often predicted using Computational Fluid Dynamics (CFD) simulations. CFD simulations are inexpensive but need accurate source boundary conditions for the precise prediction of disease transmission. Cough is found to be the prime source for generating infectious viruses. The present study was designed to develop an accurate source model to define thermo-fluid boundary conditions for a cough. The model can aid in accurately predicting the disease transmission in various indoor environments, such as aircraft cabins, office spaces and hospitals.
10.1111/j.1600-0668.2009.00619.x
The influence of gender on cough reflex sensitivity.
Dicpinigaitis P V,Rauf K
Chest
BACKGROUND:The more common occurrence in women of cough due to angiotensin-converting enzyme inhibitors raises the possibility of gender-related differences in the sensitivity of the cough reflex. Of two recent studies that evaluated cough response to inhaled capsaicin in normal subjects, one demonstrated heightened sensitivity of the cough reflex in women compared with men, while the other revealed no gender-related differences. To further investigate this question, we reviewed our experience with cough challenge testing in normal volunteers. STUDY OBJECTIVE:To compare cough reflex sensitivity in healthy adult female and male subjects. DESIGN:Retrospective data analysis. SETTING:Academic medical center. PARTICIPANTS:One hundred healthy volunteers (50 male, 50 female). INTERVENTIONS:Subjects inhaled capsaicin in ascending, doubling concentrations until the concentration inducing five or more coughs (C5) was reached. In addition, the concentration inducing two or more coughs (C2; cough threshold) was measured. RESULTS:Mean log C5 was significantly lower in women than in men: 1.02+/-0.09 (SEM) microM vs 1.41+/-0.08 microM, respectively (p=0.002). Log C2 (cough threshold) was also significantly lower in female subjects: 0.534+/-0.068 microM vs 0.870+/-0.065 microM in male subjects (p=0.00058). CONCLUSION:Healthy women have a more sensitive cough reflex than do healthy men. The reasons for this significant gender difference remain to be elucidated, but may involve a heightened sensitivity, in women, of the sensory receptors within the respiratory tract that mediate cough.
10.1378/chest.113.5.1319
Predictors of objective cough frequency in chronic obstructive pulmonary disease.
Sumner Helen,Woodcock Ashley,Kolsum Umme,Dockry Rachel,Lazaar Aili L,Singh Dave,Vestbo Jørgen,Smith Jaclyn A
American journal of respiratory and critical care medicine
RATIONALE:Cough is one of the principal symptoms of chronic obstructive pulmonary disease (COPD) but the potential drivers of cough are likely to be multifactorial and poorly understood. OBJECTIVES:To quantify cough frequency in an unselected group of subjects with COPD and investigate the relationships between cough, reported sputum production, smoking, pulmonary function, and cellular airway inflammation. METHODS:We studied 68 subjects with COPD (mean age, 65.6 ± 6.7 yr; 67.6% male; 23 smokers; 45 ex-smokers) and 24 healthy volunteers (mean age, 57.5 ± 8.9 yr; 37.5% male; 12 smokers; 12 nonsmokers). Subjects reported cough severity, cough-specific quality of life, and sputum expectoration and performed spirometry, sputum induction, cough reflex sensitivity to capsaicin, and 24-hour ambulatory cough monitoring. MEASUREMENTS AND MAIN RESULTS:COPD current smokers had the highest cough rates (median, 9 coughs/h [interquartile range, 4.3-15.6 coughs/h]), almost double that of COPD ex-smokers (4.9 [2.3-8.7] coughs/h; P = 0.018) and healthy smokers (5.3 [1.2-8.3] coughs/h; P = 0.03), whereas healthy volunteers coughed the least (0.7 [0.2-1.4] coughs/h). Cough frequency was not influenced by age or sex and only weakly correlated with cough reflex sensitivity to capsaicin (log C5 r = -0.36; P = 0.004). Reported sputum production, smoking history, and current cigarette consumption strongly predicted cough frequency, explaining 45.1% variance in a general linear model (P < 0.001). In subjects producing a sputum sample, cough frequency was related to current cigarette consumption and percentage of sputum neutrophils (P = 0.002). CONCLUSIONS:Ambulatory objective monitoring provides novel insights into the determinants of cough in COPD, suggesting sputum production, smoking, and airway inflammation may be more important than sensitivity of the cough reflex.
10.1164/rccm.201211-2000OC
Role of prostaglandin I in the bronchoconstriction-triggered cough response in guinea pigs.
Sakai Tamami,Hara Johsuke,Yamamura Kenta,Okazaki Akihito,Ohkura Noriyuki,Sone Takashi,Kimura Hideharu,Abo Miki,Yoshimura Kenichi,Fujimura Masaki,Kasahara Kazuo,Nakao Shinji
Experimental lung research
Purpose/Aim of the study: Methacholine chloride (MCh) inhalation causes bronchoconstriction and cough. Following MCh-induced bronchoconstriction, metabolic products of prostaglandin I (PGI) increase in bronchoalveolar lavage fluid (BALF), suggesting that PGI plays a role in the cough response. Accordingly, we used an experimental guinea pig model to evaluate the role of PGI in the bronchoconstriction-triggered cough response. MATERIALS AND METHODS:Experiment 1: The concentration of PGF, a stable metabolite of PGI, in BALF was assessed in animals exposed to nebulized MCh and animals exposed to nebulized saline. Experiment 2: Bronchoconstriction and cough were assessed in 3 groups of animals after MCh inhalation (a saline group, low-dose PGI group, and high-dose PGI group). Enhanced pause (Penh) was used as a measure of bronchoconstriction. Experiment 3: Bronchoconstriction and cough were assessed in 3 groups of animals (groups administered saline, a low dose of a specific antagonist of the PGI receptor (IP antagonist), and a high dose of a specific IP antagonist). RESULTS:The PGF concentration in BALF was significantly higher in the bronchoconstriction group than in the control group. In animals administered high-dose PGI, the MCh-induced increase in Penh was significantly suppressed, and the number of coughs induced by bronchoconstriction was significantly decreased. In animals treated with a high dose of an IP antagonist, the MCh-induced increase in Penh was not affected, and the number of coughs increased. CONCLUSIONS:Our results suggest that PGI ameliorates a bronchoconstriction-triggered cough. The measurement and administration of PGI may assist in the diagnosis and treatment, respectively, of the cough response triggered by bronchoconstriction.
10.1080/01902148.2019.1590883
Dual Tasking Influences Cough Sensorimotor Outcomes in Healthy Young Adults.
Perry Sarah E,Troche Michelle S
Journal of speech, language, and hearing research : JSLHR
Purpose Reflex cough is an essential airway protective mechanism that often occurs in the context of divided attention. The effect of divided attention on measures of reflexive cough airflow and sensitivity remains unknown. We present findings from a study testing the effects of divided attention (via a dual-task paradigm) on measures of reflex cough in healthy young adults. Method Volunteers ( = 20, age = 20-40 years) underwent 4 blocks of capsaicin-induced cough challenges. Within each block, capsaicin ranging from 0 to 200 μM was presented in a randomized order. Two blocks consisted of cough testing only (single task). During the other 2 blocks, participants counted tones while simultaneously undergoing cough testing (dual task). Measures of cough motor response, self-reported urge-to-cough, cough frequency, and cough airflow were collected. Results Participants coughed more in the single-task condition compared to the dual-task condition ( ≤ .001). Participants' urge-to-cough ratings were lower in the dual-task condition ( = 2, "slight") compared to the single-task condition ( = 3, "moderate"; = .007). Participants' cough reflex sensitivity thresholds were significantly increased in the dual-task condition ( = .002). Cough peak expiratory flow rates did not change between the 2 conditions ( = .34). Conclusions Somatosensation of tussive stimuli changes during dual tasking. Abnormal cortical resource allocation may be a mechanism involved in silent aspiration.
10.1044/2019_JSLHR-H-19-0122
The effect of mindfulness meditation on cough reflex sensitivity.
Young E C,Brammer C,Owen E,Brown N,Lowe J,Johnson C,Calam R,Jones S,Woodcock A,Smith J A
Thorax
BACKGROUND:Chronic cough is common, and medical treatment can be ineffective. Mindfulness is a psychological intervention that aims to teach moment-to-moment non-judgemental awareness of thoughts, feelings and sensations. METHOD:30 healthy subjects and 30 patients with chronic cough were studied in two sequential trials. For both studies, cough reflex sensitivity to citric acid (C5) was measured on two occasions, with urge to cough rated following each inhalation; between challenges subjects were randomised to (1) no intervention, (2) mindfulness or (3) no intervention but modified cough challenge (subjects suppress coughing). For the healthy volunteers, measures were 1 h apart and mindfulness was practised for 15 min. For the patients with chronic cough measures were 1 week apart and mindfulness was practised daily for 30 min. RESULTS:In healthy volunteers, median change (interquartile range (IQR)) in cough reflex sensitivity (logC5) for no intervention, mindfulness and suppression was +1.0 (0.0 to +1.3), +2.0 (+1.0 to +3.0) and +3.0 (+2.8 to +3.0) doubling concentrations (p = 0.003); there were significant reductions for both mindfulness (p = 0.043) and suppression (p = 0.002) over no intervention. In patients with cough, median change (IQR) in logC5 for no intervention, mindfulness training and voluntary suppression was 0.0 (-1.0 to +1.0), +1.0 (-0.3 to +1.0) and +1.0 (+1.0 to +2.0) doubling concentrations (p = 0.046); there was a significant reduction for suppression (p = 0.02) but not mindfulness (p = 0.35). Urge to cough did not change after mindfulness compared with control in either healthy subjects (p = 0.33) or those with chronic cough (p = 0.47). CONCLUSION:Compared with control, mindfulness decreased cough reflex sensitivity in healthy volunteers, but did not alter cough threshold in patients with chronic cough. Both groups were able to suppress cough responses to citric acid inhalation.
10.1136/thx.2009.116723
Ambulatory quantitative waking and sleeping cough assessment in patients with cystic fibrosis.
Kerem Eitan,Wilschanski Michael,Miller Nilsen L,Pugatsch Thea,Cohen Tali,Blau Hannah,Rivlin Joseph,Shoseyov David,Reha Allen,Constantine Scott,Ajayi Temitayo,Hirawat Samit,Elfring Gary L,Peltz Stuart W,Miller Langdon L
Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society
BACKGROUND:Although cough is a commonly reported symptom, objective quantitation of cough during normal activity has not been performed in patients with CF. METHODS:An ambulatory device was used to characterize cough over 24 hours. Pulmonary function and subject-reported coughing were also assessed. RESULTS:Patients included 19 clinically stable adults with CF (males:females=10:9; median age [range]=26 [19-57] years; median %-predicted FEV(1) [range]=65 [44-106]%). Median [range] cough rate was 27 [13-66] coughs/hour, with values while awake of 41 [20-102] and while asleep of 2 [0.1-7] (p<0.0001, Wilcoxon signed-rank test). Subjective reporting was consistent with objective data for wake-sleep differences, but correlated poorly with objective waking cough rate. CONCLUSIONS:Outpatient cough quantitation in patients with CF is feasible, indicates frequent coughing even during clinical stability, and may be useful in therapeutic trials in CF.
10.1016/j.jcf.2011.02.003
A Comprehensive Approach for Classification of the Cough Type.
Nemati Ebrahim,Rahman Md Mahbubur,Nathan Viswam,Vatanparvar Korosh,Kuang Jilong
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
Identifying the presence of sputum in the lung is essential in detection of diseases such as lung infection, pneumonia and cancer. Cough type classification (dry/wet) is an effective way of examining presence of lung sputum. This is traditionally done through physical exam in a clinical visit which is subjective and inaccurate. This work proposes an objective approach relying on the acoustic features of the cough sound. A total number of 5971 coughs (5242 dry and 729 wet) were collected from 131 subjects using Smartphone. The data was reviewed and annotated by a novel multi-layer labeling platform. The annotation kappa inter-rater agreement score is measured to be 0.81 and 0.37 for 1st and 2nd layer respectively. Sensitivity and specificity values of 88% and 86% are measured for classification between wet and dry coughs (highest across the literature).
10.1109/EMBC44109.2020.9175345
Interpretation of cough provoked by airway challenges.
Koskela Heikki O,Kontra Kirsi M,Purokivi Minna K,Randell Jukka T
Chest
STUDY OBJECTIVE:To analyze the cough response to three airway challenges in order to clarify whether the recording of the provoked coughs would be beneficial in the management of asthma. DESIGN:A prospective study. SETTING:University hospital. PARTICIPANTS:Fifteen healthy subjects, 16 steroid-naïve subjects with asthma, and 16 subjects with steroid-treated asthma. INTERVENTIONS:Inhalation challenges with isotonic histamine, hypertonic saline solution, and hypertonic histamine, using an ultrasonic nebulizer and 2-min tidal breathing method. MEASUREMENTS:Airflow parameters were measured with a spirometer, and the coughs were recorded manually. RESULTS:Coughing during the isotonic histamine challenge was associated with the degree of the bronchoconstriction induced. When this was taken into account, the healthy subjects coughed as frequently as the asthmatic subjects. During the two hypertonic challenges, the asthmatic subjects coughed more frequently than did the healthy subjects when the induced bronchoconstriction had not yet developed. At that stage of the hypertonic saline solution challenge, the mean coughing frequency was 0.7 coughs per minute (95% confidence interval [CI], 0.03 to 1.3 coughs per minute) for the healthy subjects, 2.7 coughs per minute (95% CI, 0.8 to 4.5 coughs per minute) for the steroid-naïve asthmatic subjects, and 1.3 coughs per minute (95% CI, 0.6 to 1.9 coughs per minute) for the steroid-treated asthmatic subjects (p = 0.018). For the hypertonic histamine challenge, the respective values were 0.8 coughs per minute (95% CI, 0.4 to 1.2 coughs per minute), 3.6 coughs per minute (95% CI, 2.4 to 4.9 coughs per minute), and 2.1 coughs per minute (95% CI, 1.0 to 3.1 coughs per minute; p = 0.001). This cough did not correlate with airway hyperresponsiveness. CONCLUSIONS:Coughing during isotonic histamine challenge seems to be a manifestation of bronchoconstriction, and recording of the coughs may not provide additional information to airflow measurements. Frequent coughing during hypertonic saline solution and hypertonic histamine challenges in the absence of bronchoconstriction is a pathologic phenomenon. Sensitivity to the cough-provoking effect of hypertonic challenges seems to be enhanced in patients with asthma but unrelated to airway hyperresponsiveness. Therefore, the recording of the provoked coughs during these challenges may add to the information obtained from airflow measurements.
10.1378/chest.128.5.3329
Effectiveness of a chronic cough management algorithm at the transitional stage from acute to chronic cough in children: a multicenter, nested, single-blind, randomised controlled trial.
O'Grady Kerry-Ann F,Grimwood Keith,Torzillo Paul J,Rablin Sheree,Lovie-Toon Yolanda,Kaus Michelle,Arnold Daniel,Roberts Jack,Buntain Helen,Adsett Don,King Alex,Scott Mark,Anderson Jennie,Toombs Maree,Chang Anne B
The Lancet. Child & adolescent health
BACKGROUND:Chronic (lasting at least 4 weeks) cough in children is an important cause of morbidity. An algorithmic approach to the management of coughs in children evaluated in observational studies and a randomised controlled trial (RCT) enrolled children referred with median cough duration of 16 weeks to specialist centres. We investigated whether applying an evidence-based cough management algorithm in non-specialist settings earlier, once cough persisted for more than 4 weeks, improved cough resolution compared with usual care. METHODS:We undertook a multicentre, single-blind RCT nested within a prospective cohort study of children (<15 years) in Australia presenting to three primary care or three hospital emergency departments with an acute respiratory illness with cough. Children were excluded if they had a known diagnosis of an underlying chronic medical condition (excluding asthma) or had an immunosuppressive illness or were taking immunomodulating drugs for more than 2 weeks in the preceding 30 days, or had severe symptoms requiring inpatient hospitalisation. Children were followed up for 8 weeks; those with a persistent cough at day 28 were randomly assigned to the cough management algorithm or to usual care. Randomisation was stratified by reason for presentation, study site, and cough duration (4 weeks to <6 weeks vs ≥6 weeks) using computer-generated permuted blocks (block size of four) with a 1:1 allocation. The primary outcome was the proportion of children with cough resolution at day 56 (defined as resolved if the child did not cough for at least 3 days and nights since day 28 or a more than 75% reduction in their average day and night cough score). Absolute risk differences (RD) were calculated by modified intention-to-treat analysis (ITT). This trial is registered with the Australia New Zealand Clinical Trials Registry, ACTRN12615000132549. FINDINGS:Between July 7, 2015, and Oct 31, 2018, 1018 children were screened, 509 were enrolled in the cohort study, and of 115 children in the ITT analysis, 57 were randomly assigned to the intervention group and 58 to the control group. Children had a median age of 1·6 years (IQR 1·0-4·5); 45 (39%) of 115 were Indigenous, and 59 (51%) were boys. By day 56, 33 (58%) of 57 children in the intervention group achieved cough resolution compared with 23 (40%) 58 in the control group; cough resolution was unknown in 12 (21%) of 57 children receiving the intervention and in 13 (22%) of 58 receiving the control. The RD assuming children with an unknown cough outcome were still coughing at day 56 was 18·3% (95% CI 0·3-36·2); the number needed-to-treat for benefit was five (95% CI 3-364); the adjusted odds ratio was 1·5 (95% CI 1·3-1·6), favouring the intervention group. INTERPRETATION:This study suggests an evidence-based cough management algorithm improves cough resolution in community-based children in the early phases of chronic cough. However, larger studies to confirm these findings in primary care are required. FUNDING:National Health and Medical Research Council.
10.1016/S2352-4642(19)30327-X
Characterization of pressure changes in the lower urinary tract during coughing with special reference to the demands on the pressure recording equipment.
Thind P,Bagi P,Lose G,Mortensen S
Neurourology and urodynamics
The exact demands on urodynamic equipment for measurement of coughs and cough associated pressure changes in the lower urinary tract have been analyzed from high-speed pressure recordings using a double microtip transducer and a storage oscilloscope. The equipment was tested in vitro by the step-test method. The natural frequency response was 175.6 Hz and the rise-time 2.5 ms, resulting in accurate measurements of frequencies up to about 60 Hz, which is way above the clinically measured frequencies. Four men and 2 women, all of whom were healthy volunteers, were examined in the supine position with an empty bladder. Pressures were measured in the bladder and in the external sphincter zone of the urethra. The spectral power density of the bladder and urethral pressures were calculated by Fourier analysis. The pressure changes in the urethra were in all volunteers equal to or slower than in the bladder. The analysis of the spectral power density showed that 99% of the pressure changes could be recorded with an instrument capable of recording 9 Hz frequencies, i.e., with a sampling rate of 18 Hz or more.
10.1002/1520-6777(1994)13:3<219::aid-nau1930130303>3.0.co;2-e
The Effect of a Small Priming Dose of Sufentanil on Sufentanil-Induced Cough.
Zou Yi,Ling Yingzi,Wei Lai,Tang Yixun,Kong Gaoyin,Zhang Le
Journal of perianesthesia nursing : official journal of the American Society of PeriAnesthesia Nurses
PURPOSE:The aim of this study was to investigate the effect of a small priming dose of sufentanil on sufentanil-induced cough during induction of anesthesia. DESIGN:Randomized controlled trial. METHODS:Adult patients (N = 220) aged 18 to 65 years undergoing general anesthesia were randomized into two groups (n = 110), a total dose of sufentanil 0.4 mcg/kg was used during induction of anesthesia. Group P (intervention) received a bolus of 5 mcg of sufentanil 1 minute before a bolus of the remaining larger dose of sufentanil, whereas group C (comparison) received an equal volume of normal saline 1 minute before a bolus of the total dose of sufentanil. The incidence and severity of cough were noted for 1 minute after each injection of sufentanil or normal saline. FINDINGS:The incidence of cough in group P was significantly lower than group C (6.4% vs 21.8%, P < .001). The severity of cough in group P was significantly decreased compared with group C (P < .001). In group P, three patients (2.7%, P = .247) coughed after the priming sufentanil injection. CONCLUSIONS:A priming dose of 5 mcg of sufentanil 1 minute before a larger dose of sufentanil injection could effectively alleviate sufentanil-induced cough, the small priming dose of sufentanil could also elicit cough with a low incidence.
10.1016/j.jopan.2020.03.016
Chest wall dynamics during voluntary and induced cough in healthy volunteers.
Smith Jaclyn A,Aliverti Andrea,Quaranta Marco,McGuinness Kevin,Kelsall Angela,Earis John,Calverley Peter M
The Journal of physiology
Coughing both protects the airways from foreign material and clears excessive secretions in respiratory diseases, and therefore requires high expiratory flows. We hypothesised that the volume inspired prior to coughing (operating volume) would significantly influence the mechanical changes during coughing and thus cough flow. Sixteen healthy volunteers (6 female, mean age 31 ± 10 years) performed six single voluntary coughs from four different operating volumes (10%, 30%, 60% and 90% of vital capacity) followed by three peals of voluntary and citric acid-induced coughs. During coughing we simultaneously measured (i) chest and upper abdominal wall motion using opto-electronic plethysmography (OEP), (ii) intra-thoracic and intra-abdominal pressures with a balloon catheter in each compartment and (iii) flow at the mouth. Operating volume was the most important determinant of the peak flow achieved and volume expelled during coughing, but had little influence on the pressures generated. The duration of single coughs increased with operating volume, whereas coughs were much shorter and varied little during peals. Voluntary cough peals were also associated with significant blood shift away from the trunk. In conclusion, this study has shown that operating volume is the most important determinant of cough peak flow and volume expelled in healthy individuals. During peals of coughs, similar mechanical effects were achieved more rapidly, suggesting a modification of the motor pattern with improved efficiency. Future studies investigating cough mechanics in health and disease should control for the influence of operating volume.
10.1113/jphysiol.2011.213157
Dual Tasking Influences Cough Reflex Outcomes in Adults with Parkinson's Disease: A Controlled Study.
Dysphagia
Coughing is an essential airway protective reflex. In healthy young adults, cough somatosensation changes when attention is divided (dual tasking). Whether the same is true in populations at risk of aspiration remains unknown. We present findings from a controlled study testing the effects of divided attention (via a dual-task paradigm) on measures of reflex cough in Parkinson's disease. Volunteers with Parkinson's disease (n = 14, age = 43-79 years) and 14 age-matched controls underwent five blocks of capsaicin-induced cough challenges. Within each block, capsaicin ranging from 0 to 200 μM was presented in a randomized order. Two blocks consisted of cough testing only (single task), and two blocks consisted of cough testing with simultaneous tone counting (dual task). Finally, participants completed a suppressed cough task. Measures of cough motor response, self-reported urge to cough, cough frequency, and cough airflow were collected. Historical data from healthy young adults was included for comparison. Between-group analyses revealed no differences between single- and dual-cough-task responses. However, post hoc analysis revealed a significant relationship between dual-task errors and cough frequency that was strongest in people with Parkinson's disease [p = 0.004, r = 0.52]. Specifically, greater errors were associated with fewer reflexive coughs. Unlike healthy participants, participants with Parkinson's disease did not change the number of coughs between the single-, dual-, and suppressed-task conditions [p > 0.05]. When distracted, people with Parkinson's disease may prioritize coughing differently than healthy controls. Abnormal cortical resource allocation may be a mechanism involved in aspiration in this population.
10.1007/s00455-020-10223-x
Fifteen-minute consultation: A structured approach to the management of chronic cough in a child.
Alviani Cherry,Ruiz Gary,Gupta Atul
Archives of disease in childhood. Education and practice edition
Coughing is a primary pulmonary defence mechanism that enhances clearance of secretions and particles from the airways and protects against aspiration of foreign materials. Coughing may affect 30% of children at any given time (1). Many are healthy children but some may have serious underlying disease. Childhood cough accounts for a large number of consultations and 80% of families who are referred to a paediatric respiratory clinic for chronic cough have sought medical advice five times or more (2). The majority of childhood coughs are secondary to an acute respiratory tract infection and will improve once the infection resolves, usually within 1 to 3 weeks. With pre-school children who may experience between 6 and 10 respiratory infections a year differentiating acute recurrent cough from chronic cough is key (Table 1). Chronic cough can significantly impact a family's quality of life, as it affects the child's sleep, school attendance and play. Parents experience distress and anxiety, worrying that the cough may lead to long-term chest damage or even death (3). This article aims to guide clinicians through the assessment of the child with a chronic cough. It will discuss identifying causes, use of first line investigations, initiating appropriate management and addressing parental anxiety and exacerbating factors (4,5).
10.1136/archdischild-2017-313496
[Use of an accelerometer to measure coughing].
Fukakusa M,Sato T,Furuhata H
Nihon Kokyuki Gakkai zasshi = the journal of the Japanese Respiratory Society
Coughing was detected by measuring body-surface acceleration. Twenty-seven patients with a chief complaint of coughing were studied. The sensor used is an apparatus for sound communication in aircraft, in which cranial vibrations that occur as the pilot speaks are converted into acceleration waves. An acceleration sensor was fixed to the body of each subject. The acceleration of the chest wall was recorded as a voltage change. Subjects rested in bed to exclude acceleration due to body movement. Acceleration waves of large amplitude were recognized during coughing. Conversation or laughter only caused very weak acceleration waves. Sound has often been used as an indicator of coughing, because coughing was thought to be one kind of human vocalization. However, distinguishing speaking from coughing was difficult, and complicated analysis was necessary. We regarded coughing as a movement causing acceleration of the body surface, and measured it without using sound. We plan to collect data on acceleration of the body surface in 3 dimensions simultaneously. After a continuous long-term recorder of coughing is developed the effects of antitussive drugs can be assessed.
Cough Characteristics and Healthcare Journeys of Chronic Cough Patients in Community-Based Populations in South Korea and Taiwan.
Lung
PURPOSE:This study aimed to understand the cough characteristics and health journeys among community-based chronic cough (CC) patients, and their characteristics associated with healthcare visits. METHODS:A population-based cross-sectional study was conducted in 2020, using the South Korea and Taiwan National Health and Wellness Survey (NHWS) and CC surveys. Patients with current CC were defined by daily coughing for > 8 weeks in the past 12 months and currently coughing at the time of survey. The survey items pertained to CC patients' treatment journey and cough characteristics. RESULTS:Patients with current CC in South Korea and Taiwan, respectively, had cough duration for 3.45 ± 5.13 years and 5.75 ± 7.28 years and cough severity visual analogue scale (VAS) scores of 4.50 ± 2.15 and 4.46 ± 1.92 out of 0-10 scale, with 70.3% and 57.9% having spoken with a physician about cough. Compared to CC patients who had not visited healthcare professionals for cough, those who visited reported more severe cough (VAS: 3.89 ± 1.71 vs. 4.6 ± 2.02; p = 0.009), worse cough-specific quality of life (Leicester Cough Questionnaire: 16.20 ± 3.23 vs.13.45 ± 2.68, p < 0.001), greater symptom severity (Hull Airway Reflux Questionnaire: 16.73 ± 15.16 vs. 24.57 ± 13.38; p < 0.001), and more urinary incontinence (13.6 vs. 26.5%, p = 0.027). More than 50% of patients perceived cough medication(s) as not or a little useful and 25% felt their physicians did not well understand how CC impacts their life. CONCLUSION:Cough is frequently severe and persistent among community-based CC patients. They experience several issues in their health journey, including treatment ineffectiveness and physician's understanding. Further efforts are warranted to reduce CC burden in the community.
10.1007/s00408-022-00586-3
A novel automatic cough frequency monitoring system combining a triaxial accelerometer and a stretchable strain sensor.
Otoshi Takehiro,Nagano Tatsuya,Izumi Shintaro,Hazama Daisuke,Katsurada Naoko,Yamamoto Masatsugu,Tachihara Motoko,Kobayashi Kazuyuki,Nishimura Yoshihiro
Scientific reports
Objective evaluations of cough frequency are considered important for assessing the clinical state of patients with respiratory diseases. However, cough monitors with audio recordings are rarely used in clinical settings. Issues regarding privacy and background noise with audio recordings are barriers to the wide use of these monitors; to solve these problems, we developed a novel automatic cough frequency monitoring system combining a triaxial accelerator and a stretchable strain sensor. Eleven healthy adult volunteers and 10 adult patients with cough were enrolled. The participants wore two devices for 30 min for the cough measurements. An accelerator was attached to the epigastric region, and a stretchable strain sensor was worn around their neck. When the subjects coughed, these devices displayed specific waveforms. The data from all the participants were categorized into a training dataset and a test dataset. Using a variational autoencoder, a machine learning algorithm with deep learning, the components of the test dataset were automatically judged as being a "cough unit" or "non-cough unit". The sensitivity and specificity in detecting coughs were 92% and 96%, respectively. Our cough monitoring system has the potential to be widely used in clinical settings without any concerns regarding privacy or background noise.
10.1038/s41598-021-89457-0
The effectiveness of 4% intracuff lidocaine in reducing coughing during emergence from general anesthesia in smokers undergoing procedures lasting less than 1.5 hours.
Wetzel Laura E,Ancona Amy L,Cooper Andrew S,Kortman Amy J,Loniewski Gayle B,Lebeck Lynn L
AANA journal
Coughing commonly occurs in patients emerging from general endotracheal anesthesia and is prominent in smokers due to underlying airway irritation. Clinical techniques used to mitigate emergence coughing include intravenous narcotics, intravenous or topical lidocaine, and deep extubation. Reduction of coughing by instilling lidocaine into the endotracheal tube cuff has been shown to be effective in long cases. Research has not confirmed efficacy of this technique in short cases. Does administration of intracuff lidocaine decrease coughing during emergence of smokers in short cases requiring general endotracheal anesthesia? This study was a randomized, double blind, posttest-only design that included 38 patients. Investigators recruited the subjects, obtained consent, and provided a syringe containing 5 mL of 4% lidocaine or 5 mL of saline to the anesthesia provider. At time of intubation, the provider injected the contents of the syringe into the endotracheal tube cuff. The control group received 5 mL of saline, and the experimental group received 5 mL of 4% lidocaine. On emergence, the anesthesia provider counted and recorded the number of coughs before awake extubation. This study did not show a correlation between use of intracuff lidocaine and a decrease in emergence coughing in procedures lasting less than 1.5 hours in patients who smoke.
Acoustic Monitoring of Night-Time Respiratory Symptoms in 14 Patients with Exacerbated COPD Over a 3- Week Period.
International journal of chronic obstructive pulmonary disease
Introduction:In clinical practice, wheezing and coughing represent a worsening of the respiratory situation of COPD patients and should be monitored long-term during and after an Acute Exacerbation of COPD (AECOPD) to observe the therapy. We investigated if overnight monitoring of wheezing and coughing is feasible during AECOPD and whether automatic long - term monitoring enables an objective assessment during and after an AECOPD. Methods:In 14 patients (age: 56-80 years) with pre-existing COPD (stages B-D) nighttime wheezing and coughing events were monitored for a period of three weeks. The portable LEOSound monitor recorded three nights into AECOPD (nights 1, 3 and 6) during the hospital stay, and the 20th night post- AECOPD ambulatory. Before each recording the subjective symptom severity was assessed by a COPD Assessment Test (CAT) and a Modified British Medical Research Council (MMRC) dyspnoea index questionnaire. Results:In all 14 patients, lung sounds were recorded in good quality during each of the 4 recording nights. Wheezing ranged between 5% and 90% (79 -539.5 minutes) of the recording time on the first night. All patients showed some coughs, in four patients coughing was particularly pronounced and largely receding over the total investigation period. As group, the percentages of wheezing and the number of coughs did not show significant differences between the four recording times. The CAT scores (p<0.001) declined over the course of investigation period, suggesting a subjective improvement of symptoms. Conclusion:The observational study showed that standardized long-term recording can be performed in high-quality during acute COPD exacerbation as it does not require the patient's cooperation. The good-quality data of coughs and wheezing were analyzed qualitatively and quantitatively. The long-term presentation of respiratory symptoms during an AECOPD offers the opportunity to evaluate factors that influence exacerbations and therapeutic approaches.
10.2147/COPD.S377069
Role of bradykinin and tachykinins in the potentiation by enalapril of coughing induced by citric acid in pigs.
Moreaux B,Advenier C,Gustin P
Fundamental & clinical pharmacology
Angiotensin-converting enzyme (ACE) inhibitors are among the first-choice drugs for treating hypertension and congestive heart disease. It has been reported, however, that these drugs could induce chronic cough and airway hyperresponsiveness. The aim of this work was to assess in pigs the effects of bradykinin and tachykinins on citric-acid-induced coughing after ACE inhibitor pretreatment. Coughing was induced by challenging pigs with an aerosol of 0.8 M citric acid over 15 min. Coughs were counted by a trained observer for 30 min. The animals underwent two cough induction tests two days apart (days 1 and 3), the first being taken as a control. All drugs were injected intravenously 30 min before the second challenge. In the control group, no difference was observed between days 1 and 3. The ACE inhibitor enalapril (7.5 and 15 microg/kg) caused the cough frequency to increase significantly. In contrast, a dose-related decrease was observed with Hoe140 (icatibant), a bradykinin B2 receptor antagonist (0.5 and 1 mg/kg). When both drugs were administered simultaneously (15 microg/kg for enalapril and 1 mg/kg for Hoe140), a significant increase was observed as compared with the control value obtained on day 1. When enalapril was combined with the three tachykinin receptor antagonists SR 140333 (NK1 receptor antagonist), SR 48968 (NK2 receptor antagonist) and SR 142801 (NK3 receptor antagonist), a significant decrease was observed as compared with control value obtained on day 1; the percentage of variation was also significantly different as compared with those observed in enalapril groups at both doses. These data suggest that ACE-inhibitor-induced enhancement of the cough reflex is mainly due to tachykinins and not to bradykinin in our pig model. Bradykinin, however, plays a major role in coughing induced by citric acid alone.
10.1046/j.1472-8206.2001.00008.x
Role of costal and crural diaphragm and parasternal intercostals during coughing in cats.
van Lunteren E,Daniels R,Deal E C,Haxhiu M A
Journal of applied physiology (Bethesda, Md. : 1985)
The inspiratory phase of coughs often consists of large inspired volumes and increased motor discharge to the costal diaphragm. Furthermore, diaphragm electrical activity may persist into the early expiratory portion of coughs. To examine the role of other inspiratory muscles during coughing, electromyograms (EMG) recorded from the crural diaphragm (Dcr) and parasternal intercostal (PSIC) muscles were compared to EMG of the costal diaphragm (Dco) in anesthetized cats. Tracheal or laryngeal stimulation typically produced a series of coughs, with variable increases in peak inspiratory EMGs of all three muscles. On average, peak inspiratory EMG of Dco increased to 346 +/- 60% of control (P less than 0.001), Dcr to 514 +/- 82% of control (P less than 0.0002), and PSIC to 574 +/- 61% of control (P less than 0.0005). Augmentations of Dcr and PSIC EMG were both significantly greater than of Dco EMG (P less than 0.05 and P less than 0.002, respectively). In most animals, EMG of Dco correlated significantly with EMG of Dcr and of PSIC during different size coughs. Electrical activity of all three muscles persisted into the expiratory portions of many (but not all) coughs. The duration of expiratory activity lasted on average 0.17 +/- 0.03 s for Dco, 0.25 +/- 0.06 s for Dcr, and 0.31 +/- 0.09 s for PSIC. These results suggest that multiple respiratory muscles are recruited during inspiration of coughs, and that the persistence of electrical activity into expiration of coughs is not unique to the costal diaphragm.
10.1152/jappl.1989.66.1.135
Identifying unique spectral fingerprints in cough sounds for diagnosing respiratory ailments.
Scientific reports
Coughing, a prevalent symptom of many illnesses, including COVID-19, has led researchers to explore the potential of cough sound signals for cost-effective disease diagnosis. Traditional diagnostic methods, which can be expensive and require specialized personnel, contrast with the more accessible smartphone analysis of coughs. Typically, coughs are classified as wet or dry based on their phase duration. However, the utilization of acoustic analysis for diagnostic purposes is not widespread. Our study examined cough sounds from 1183 COVID-19-positive patients and compared them with 341 non-COVID-19 cough samples, as well as analyzing distinctions between pneumonia and asthma-related coughs. After rigorous optimization across frequency ranges, specific frequency bands were found to correlate with each respiratory ailment. Statistical separability tests validated these findings, and machine learning algorithms, including linear discriminant analysis and k-nearest neighbors classifiers, were employed to confirm the presence of distinct frequency bands in the cough signal power spectrum associated with particular diseases. The identification of these acoustic signatures in cough sounds holds the potential to transform the classification and diagnosis of respiratory diseases, offering an affordable and widely accessible healthcare tool.
10.1038/s41598-023-50371-2
Coordination of cough and swallow: a meta-behavioral response to aspiration.
Respiratory physiology & neurobiology
Airway protections is the prevention and/or removal of material by behaviors such as cough and swallow. We hypothesized these behaviors are coordinated to respond to aspiration. Anesthetized animals were challenged with simulated aspiration that induced both coughing and swallowing. Electromyograms of upper airway and respiratory muscles together with esophageal pressure were recorded to identify and evaluate cough and swallow. During simulated aspiration, both cough and swallow intensity increased and swallow duration decreased consistent with rapid pharyngeal clearance. Phase restriction between cough and swallow was observed; swallow was restricted to the E2 phase of cough. These results support three main conclusions: 1) the cough and swallow pattern generators are tightly coordinated so as to generate a protective meta-behavior; 2) the trachea provides feedback on swallow quality, informing the brainstem about aspiration incidences; and 3) the larynx and upper esophageal sphincter act as two separate valves controlling the direction of positive and negative pressures from the upper airway into the thorax.
10.1016/j.resp.2013.08.009
The course of lung inflation alters the central pattern of tracheobronchial cough in cat-The evidence for volume feedback during cough.
Respiratory physiology & neurobiology
The effect of volume-related feedback and output airflow resistance on the cough motor pattern was studied in 17 pentobarbital anesthetized spontaneously-breathing cats. Lung inflation during tracheobronchial cough was ventilator controlled and triggered by the diaphragm electromyographic (EMG) signal. Altered lung inflations during cough resulted in modified cough motor drive and temporal features of coughing. When tidal volume was delivered (via the ventilator) there was a significant increase in the inspiratory and expiratory cough drive (esophageal pressures and EMG amplitudes), inspiratory phase duration (CTI), total cough cycle duration, and the duration of all cough related EMGs (Tactive). When the cough volume was delivered (via the ventilator) during the first half of inspiratory period (at CTI/2-early over inflation), there was a significant reduction in the inspiratory and expiratory EMG amplitude, peak inspiratory esophageal pressure, CTI, and the overlap between inspiratory and expiratory EMG activity. Additionally, there was significant increase in the interval between the maximum inspiratory and expiratory EMG activity and the active portion of the expiratory phase (CTE1). Control inflations coughs and control coughs with additional expiratory resistance had increased maximum expiratory esophageal pressure and prolonged CTE1, the duration of cough abdominal activity, and Tactive. There was no significant difference in control coughing and/or control coughing when sham ventilation was employed. In conclusion, modified lung inflations during coughing and/or additional expiratory airflow resistance altered the spatio-temporal features of cough motor pattern via the volume related feedback mechanism similar to that in breathing.
10.1016/j.resp.2016.04.008
Capsaicin cough sensitivity is decreased in smokers.
Millqvist E,Bende M
Respiratory medicine
Although capsaicin provocation has been used to evaluate treatment against cough, which is one of the most common respiratory symptoms, there are still methodological considerations that are not fully known. Capsaicin stimulates the unmyelinated slow C-fibres of the sensory nervous system, which leads to coughing. Smoking often leads to respiratory symptoms with cough and phlegm. The aim of this study was to examine the effect of smoking on capsaicin provocation. Subjectively healthy smokers and non-smokers were challenged with capsaicin in increasing doses. The coughs were counted and irritation of the lower airways was graded on a symptom score. Smokers reacted to provocation with significantly fewer coughs, but there was no difference regarding other symptoms. These results are in agreement with the hypothesis that nicotine inhibits or blocks C-fibres of the sensory nervous system of the lower respiratory tract. Clinically, this may serve to explain increasing airway symptoms that are often seen after cessation of smoking.
10.1053/rmed.2000.0965
[Non-invasive ventilation: possibilities and limitations in patients with reduced ability to cough].
Wiebel M
Pneumologie (Stuttgart, Germany)
BACKGROUND:Neuromuscular diseases cover a wide range of pathologies, which are slowly or rapidly progressive. Besides the reduced capacity of the inspiratory muscles there is a limitation of expiration which compromises coughing. Ventilatory respiratory insufficiency (VRI) develops in stages, beginning during sleep with hypercapnia manifesting later on. Several retrospective studies have shown an improved alveolar ventilation, survival and quality of life for most NMD, even in non-bulbar ALS. The initiation of NIV is seen as apropriate when VRI in sleep develops. But patient acceptance to use NIV for more than 4 hours must be taken into account. NIV is limited by the interface which may cause skin abrasions or leakage due to pressure. NIV may be used day and night in stable conditions and with assistance experienced in mechanically-assisted coughing (MAC). The discussion of whether to perform tracheostomy remains a preeminent topic especially in ALS. CONCLUSION:NIV is effective in NMD and improves and prolongs life in slowly progressive NMD. Mask problems, leakage and bulbar dysfunction can limit the effectiveness. MAC is a tool that is very useful for elimination of bronchial secretions.
10.1055/s-2007-1016429
Laryngeal Electromyographic Findings in a Cohort of Recalcitrant Chronic Neurogenic Cough Patients.
Zalvan Craig H,Yuen Erick,Thomas Anila M,Benson Brian E
Journal of voice : official journal of the Voice Foundation
OBJECTIVES:To evaluate the laryngeal electromyography findings of bilateral thyroarytenoid muscles in 10 patients with chronic, intractable coughing. METHODS:This is a retrospective cohort case series. Clinical records were reviewed for demographic information, symptoms, and findings on bilateral laryngeal EMG for 10 patients referred for chronic coughing. RESULTS:All thyroarytenoid muscles tested demonstrated electromyographic evidence of neuropathy, with signs of denervation and reinnervation. There was reduced recruitment in all 20 thyroarytenoid muscles studied. In addition, polyphasic motor units were seen in all thyroarytenoid muscles, with increased amplitude in 18 of 20 thyroarytenoid muscles and increased duration in 17 of 20 thyroarytenoid muscles. Additionally, there was electromyographic evidence of synkinesis in 19 of 20 thyroarytenoid muscles studied, a sign of aberrant reinnervation. CONCLUSION:Patients with intractable coughing, despite numerous modalities of treatment, potentially have bilateral neuropathy of the recurrent laryngeal nerves suggesting the potential peripheral as well as central neuropathic changes as the etiology.
10.1016/j.jvoice.2020.01.024
The Wide-Ranging Spectrum of Cough-Induced Complications and Patient Harm.
The American journal of medicine
Cough is one of the most common complaints encountered in every setting; however, complications associated with coughing have received relatively little attention. An exhaustive systematic review of the English literature revealed an exceedingly large and varied spectrum of cough-induced complications affecting many systems, including upper airways, chest wall and thorax, abdominal wall, heart and aorta, central nervous system, eye, gastrointestinal tract, urogenital system, and emotional and psychological harm. Prospective studies and prevalence data are conspicuously missing. Reported cough-induced pathology ranges from rare (the majority) to common and from trivial (eg, lightheadedness, subconjunctival hemorrhage) to severe and life-threatening (eg, cervical artery dissection, rupture of a normal spleen). Other seemingly benign entities may mask a serious underlying pathology (eg, cough headache, cough syncope). A substantial proportion of patients experience anxiety and insomnia, and their quality of life is affected. Thus, the wide spectrum of cough-induced pathology need to be recognized and considered in patients complaining of cough. Suppression of cough must not be neglected in patients at risk, and areas of uncertainty need to be clarified by future prospective studies.
10.1016/j.amjmed.2019.12.044
Chronic tobacco smoke exposure increases cough to capsaicin in awake guinea pigs.
Bergren D R
Respiration physiology
Chronic exposure to irritants such as tobacco smoke (TS) can induce spontaneous and enhanced irritant-induced coughing, especially in asthma. To determine if the mechanism of enhanced coughing involves activation of capsaicin-sensitive sensory receptors (C-fibers), we exposed both non-sensitized (NS) and ovalbumin-sensitized guinea pigs to TS (5 mg/L air, 30 min exposure, and 7 days/week). Similar groups were exposed to compressed air. After 90 days of exposure, we challenged the airways with capsaicin, bradykinin, histamine and methacholine. Capsaicin induced coughing as well as bronchoconstriction in guinea pigs exposed to TS. In ovalbumin (OA) guinea pigs coughing and bronchoconstriction were enhanced. Tachykinin receptor antagonists attenuated coughing to both capsaicin and acute TS challenge. Bradykinin also induced coughing and bronchoconstriction in guinea pigs exposed to TS. There was no statistical separation between the two TS groups however. Histamine and methacholine induced similar bronchoconstriction but fewer coughs in all four experimental groups. In conclusion, chronic TS exposure induced coughing to capsaicin and bradykinin challenge. The effect of capsaicin was further enhanced in OA guinea pigs. Enhanced coughing induced by TS exposure likely involves activation of capsaicin-sensitive sensory C-fibers and neuropeptide release with possible subsequent activation of rapidly-adapting receptors.
A Novel Multi-Centroid Template Matching Algorithm and Its Application to Cough Detection.
Zhang Shibo,Nemati Ebrahim,Ahmed Tousif,Rahman Md Mahbubur,Kuang Jilong,Gao Alex
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
Cough is a major symptom of respiratory-related diseases. There exists a tremendous amount of work in detecting coughs from audio but there has been no effort to identify coughs from solely inertial measurement unit (IMU). Coughing causes motion across the whole body and especially on the neck and head. Therefore, head motion data during coughing captured by a head-worn IMU sensor could be leveraged to detect coughs using a template matching algorithm. In time series template matching problems, K-Nearest Neighbors (KNN) combined with elastic distance measurement (esp. Dynamic Time Warping (DTW)) achieves outstanding performance. However, it is often regarded as prohibitively time-consuming. Nearest Centroid Classifier is thereafter proposed. But the accuracy is comprised of only one centroid obtained for each class. Centroid-based Classifier performs clustering and averaging for each cluster, but requires manually setting the number of clusters. We propose a novel self-tuning multi-centroid template-matching algorithm, which can automatically adjust the number of clusters to balance accuracy and inference time. Through experiments conducted on synthetic datasets and a real-world earbud-based cough dataset, we demonstrate the superiority of our proposed algorithm and present the result of cough detection with a single accelerometer sensor on the earbuds platform.Clinical relevance- Coughing is a ubiquitous symptom of pulmonary disease, especially for patients with COPD and asthma. This work explores the possibility and and presents the result of cough detection using an IMU sensor embedded in earables.
10.1109/EMBC46164.2021.9629993
Effect of e-Cigarette Use on Cough Reflex Sensitivity.
Dicpinigaitis Peter V,Lee Chang Alfredo,Dicpinigaitis Alis J,Negassa Abdissa
Chest
BACKGROUND:E-cigarettes (e-cigs) have attained widespread popularity, yet knowledge of their physiologic effects remains minimal. The aim of this study was to evaluate the effect of a single exposure to e-cig vapor on cough reflex sensitivity. METHODS:Thirty healthy nonsmokers underwent cough reflex sensitivity measurement using capsaicin cough challenge at baseline, 15 min, and 24 h after e-cig exposure (30 puffs 30 s apart). The end point of cough challenge is the concentration of capsaicin inducing five or more coughs (C5). The number of coughs induced by each e-cig inhalation was counted. A subgroup of subjects (n = 8) subsequently underwent an identical protocol with a non-nicotine-containing e-cig. RESULTS:Cough reflex sensitivity was significantly inhibited (C5 increased) 15 min after e-cig use (?0.29; 95% CI, ?0.43 to ?0.15; P < .0001); 24 h later, C5 returned to baseline (0.24; 95% CI, 0.10-0.38; P = .0002 vs post-15-min value). A subgroup of eight subjects demonstrating the largest degree of cough reflex inhibition had no suppression after exposure to a non-nicotine-containing e-cig (P = .0078 for comparison of ?C5 after nicotine vs non-nicotine device). Furthermore, more coughing was induced by the nicotine-containing vs non-nicotine-containing device (P = .0156). CONCLUSIONS:A single session of e-cig use, approximating nicotine exposure of one tobacco cigarette, induces significant inhibition of cough reflex sensitivity. Exploratory analysis of a subgroup of subjects suggests that nicotine is responsible for this observation. Our data, consistent with previous studies of nicotine effect, suggest a dual action of nicotine: an immediate, peripheral protussive effect and a delayed central antitussive effect. TRIAL REGISTRY:ClinicalTrials.gov; No.: NCT02203162; URL: www.clinicaltrials.gov.
10.1378/chest.15-0817
TripletCough: Cougher Identification and Verification From Contact-Free Smartphone-Based Audio Recordings Using Metric Learning.
IEEE journal of biomedical and health informatics
Cough, a symptom associated with many prevalent respiratory diseases, can serve as a potential biomarker for diagnosis and disease progression. Consequently, the development of cough monitoring systems and, in particular, automatic cough detection algorithms have been studied since the early 2000s. Recently, there has been an increased focus on the efficiency of such algorithms, as implementation on consumer-centric devices such as smartphones would provide a scalable and affordable solution for monitoring cough with contact-free sensors. Current algorithms, however, are incapable of discerning between coughs of different individuals and, thus, cannot function reliably in situations where potentially multiple individuals have to be monitored in shared environments. Therefore, we propose a weakly supervised metric learning approach for cougher recognition based on smartphone audio recordings of coughs. Our approach involves a triplet network architecture, which employs convolutional neural networks (CNNs). The CNNs of the triplet network learn an embedding function, which maps Mel spectrograms of cough recordings to an embedding space where they are more easily distinguishable. Using audio recordings of nocturnal coughs from asthmatic patients captured with a smartphone, our approach achieved a mean accuracyof 88 % ( ± 10 % SD) on two-way identification tests with 12 enrollment samples and accuracy of 80 % and an equal error rate (EER) of 20 % on verification tests. Furthermore, our approach outperformed human raters with regard to verification tests on average by 8% in accuracy, 4% in false acceptance rate (FAR), and 12% in false rejection rate (FRR). Our code and models are publicly available.
10.1109/JBHI.2022.3152944
The size and concentration of droplets generated by coughing in human subjects.
Yang Shinhao,Lee Grace W M,Chen Cheng-Min,Wu Chih-Cheng,Yu Kuo-Pin
Journal of aerosol medicine : the official journal of the International Society for Aerosols in Medicine
This work investigated the size distribution of the droplet nuclei and coughed droplets by test subjects. The size distributions of droplet nuclei coughed by test subjects were determined with an aerodynamic particle sizer (APS) and scanning mobility particle sizer (SMPS) system (system 1). Coughed droplets were only sampled with the APS system (system 2). Two different schemes were employed in system 2. Furthermore, the size distribution of coughed droplets of different ages and gender was investigated to identify the effects of age and gender on droplet size distribution. Results indicated the total average size distribution of the droplet nuclei was 0.58-5.42 microm, and 82% of droplet nuclei centered in 0.74-2.12 microm. The entire average size distribution of the coughed droplets was 0.62-15.9 microm, and the average mode size was 8.35 microm. The size distribution of the coughed droplets was multimodal. The size distribution of coughed droplets showed three peaks at approximately 1 microm, 2 microm, and 8 microm. These analytical findings indicate that variation for average droplet size among the three age groups was insignificant (p > 0.1). Moreover, the variation in average droplet size between males and females was also insignificant (p > 0.1). Also, the variation in droplet concentration between males and females was significant (p > 0.1). Droplet nuclei concentrations from male subjects were considerably higher than that from females. Comparison of the droplet concentrations for subjects in different age groups demonstrated that subjects in the 30-50-year age group have the largest droplet concentrations.
10.1089/jam.2007.0610
Cough reflex in allergic dogs.
House Aileen,Celly Chander,Skeans Susan,Lamca James,Egan Robert W,Hey John A,Chapman Richard W
European journal of pharmacology
This study investigated the effects of antigen challenge on the cough reflex in dogs that were neonatally sensitized to ragweed. Tidal volume (V(T)), respiratory rate (f), pulmonary resistance (R(L)), dynamic lung compliance (C(Dyn)) and the number and amplitude (increase in mean peak expiratory pressure) of coughs induced by mechanical stimulation of the intrathoracic trachea were measured in propofol-anesthetized dogs. Aerosolized ragweed challenge had no effect to induce spontaneous cough but increased f and R(L) and reduced V(T) and C(Dyn). Mechanical stimulation of the intrathoracic trachea at this time produced 19+/-5 coughs with an average increase in cough amplitude of 11+/-1 cm H(2)O which differed significantly from the number (9+/-2 coughs) and amplitude (30+/-5.5 cm H(2)O) of mechanically induced coughs after treatment with aerosolized saline. Both the number and amplitude of mechanically induced coughs returned to baseline values by 24-48 h after the ragweed challenge. Similar results were obtained after challenge with aerosolized histamine (0.3-1% histamine) that did not induce spontaneous coughs but increased f, reduced V(T) and decreased C(Dyn) and increased the number but reduced the amplitude of the mechanically induced coughs. In conclusion, both antigen and histamine bronchoprovocation changed the characteristics of the mechanically induced cough in dogs to a response of increased cough number but reduced mean expiratory cough amplitude.
10.1016/j.ejphar.2004.03.053
The COUGHVID crowdsourcing dataset, a corpus for the study of large-scale cough analysis algorithms.
Scientific data
Cough audio signal classification has been successfully used to diagnose a variety of respiratory conditions, and there has been significant interest in leveraging Machine Learning (ML) to provide widespread COVID-19 screening. The COUGHVID dataset provides over 25,000 crowdsourced cough recordings representing a wide range of participant ages, genders, geographic locations, and COVID-19 statuses. First, we contribute our open-sourced cough detection algorithm to the research community to assist in data robustness assessment. Second, four experienced physicians labeled more than 2,800 recordings to diagnose medical abnormalities present in the coughs, thereby contributing one of the largest expert-labeled cough datasets in existence that can be used for a plethora of cough audio classification tasks. Finally, we ensured that coughs labeled as symptomatic and COVID-19 originate from countries with high infection rates. As a result, the COUGHVID dataset contributes a wealth of cough recordings for training ML models to address the world's most urgent health crises.
10.1038/s41597-021-00937-4
INDIan Consensus on the mAnagemenT of cOugh at pRimary care setting (INDICATOR).
The Journal of the Association of Physicians of India
BACKGROUND:Cough has a prevalence of 9.6% globally and 5-10% in India. Though it is a reflex action, it affects an individual's quality of life (QoL) when uncontrolled. There was a need to create an integrated guidance document on managing cough focused on primary care physicians in the Indian setting. This consensus intends to bridge this gap by providing clinical recommendations to diagnose and manage cough in primary healthcare in India. MATERIALS AND METHODS:The modified Delphi method was used to arrive at a consensus on clinical statements. The panel comprised 10 experts, including pulmonologists, otolaryngologists, a pediatrician, and a general physician. The statements were discussed under the following domains: definition, etiology, diagnosis, and treatment. RESULTS:A total of 109 clinical statements were framed, with 75 reaching consensus, 13 reaching near consensus, and 21 reaching no consensus. The experts recommended empiric use of nonopioid antitussive agents for symptomatic relief of acute dry cough. The use of oral antihistamines, oral decongestants, or mucoactive agents as a part of fixed-dose combinations (FDCs) in cough associated with rhinitis or upper airway cough syndrome (UACS) can be considered for symptomatic relief. Maintaining good hydration is important to manage a productive cough. Codeine-based preparations are to be considered as a last resort in patients with an unexplained chronic cough when other treatments have failed. Additionally, insights were captured on red flag signs, nonpharmacologic therapy, special populations, and referral to higher centers. Experts have also proposed a management algorithm with an integrated care pathway approach for acute, subacute, and chronic coughs. CONCLUSION:The present consensus fills the existing need and may guide the physician to successfully diagnose and manage cough in the primary healthcare setting in India.
10.5005/japi-11001-0275
Cough responsiveness in neurogenic dysphagia.
Smith P E,Wiles C M
Journal of neurology, neurosurgery, and psychiatry
OBJECTIVES:In neurogenic dysphagia a good cough is important for airway protection. If triggering of cough, or its effectiveness, is impaired this might result in an increased aspiration risk. Capsaicin, an agent which induces cough through sensory nerve stimulation, was used to test cough sensitivity in groups of patients with and without neurogenic dysphagia. METHODS:On the basis of swallowing speed (ml/s) in a validated water test 28 alert neurological inpatients (16 women, aged 22-71 years) were classified into 13 with abnormal and 15 with normal swallowing (median swallowing speed 23% and 99%, median volume/swallow 43% and 106% of that predicted for age and sex respectively: p<0.001). Capsaicin nebulised on air in saline was inhaled via a low resistance valve using a mouthpiece and noseclip. Up to seven incremental concentrations of capsaicin ranging from 0.07-20.0 x 10(-4) mol/l were each inhaled for up to a minute. A pneumotachograph connected to the expiratory limb gave a paper recording of expiratory air flow. Coughs were recorded as high flow expirations of short duration. Capsaicin concentrations at first cough (threshold) were recorded; concentrations at frequencies of 10 and 20 coughs/minute were interpolated from the dose-response curve. RESULTS:Cough threshold tended to be lower in those with abnormal swallowing (non-significant): the (log) concentration of capsaicin producing 10 or 20 coughs/ minute also tended to be lower (p=0.12 and 0.07 respectively) in those with abnormal swallowing. CONCLUSION:Contrary to expectation, these results suggest that cough responsiveness is enhanced in alert patients with neurogenic dysphagia even after allowing for diagnostic category, the possible presence of a bulbar upper motor neuron lesion, or voluntary respiratory capacity. It is concluded that these patients with neurogenic dysphagia do not have a reduced sensitivity of cough triggering.
10.1136/jnnp.64.3.385
A quantitative evaluation of aerosol generation during awake tracheal intubation.
Anaesthesia
Aerosol-generating procedures are medical interventions considered high risk for transmission of airborne pathogens. Tracheal intubation of anaesthetised patients is not high risk for aerosol generation; however, patients often perform respiratory manoeuvres during awake tracheal intubation which may generate aerosol. To assess the risk, we undertook aerosol monitoring during a series of awake tracheal intubations and nasendoscopies in healthy participants. Sampling was undertaken within an ultraclean operating theatre. Procedures were performed and received by 12 anaesthetic trainees. The upper airway was topically anaesthetised with lidocaine and participants were not sedated. An optical particle sizer continuously sampled aerosol. Passage of the bronchoscope through the vocal cords generated similar peak median (IQR [range]) aerosol concentrations to coughing, 1020 (645-1245 [120-48,948]) vs. 1460 (390-2506 [40-12,280]) particles.l respectively, p = 0.266. Coughs evoked when lidocaine was sprayed on the vocal cords generated 91,700 (41,907-166,774 [390-557,817]) particles.l which was significantly greater than volitional coughs (p < 0.001). For 38 nasendoscopies in 12 participants, the aerosol concentrations were relatively low, 180 (120-525 [0-9552]) particles.l , however, five nasendoscopies generated peak aerosol concentrations greater than a volitional cough. Awake tracheal intubation and nasendoscopy can generate high concentrations of respiratory aerosol. Specific risks are associated with lidocaine spray of the larynx, instrumentation of the vocal cords, procedural coughing and deep breaths. Given the proximity of practitioners to patient-generated aerosol, airborne infection control precautions are appropriate when undertaking awake upper airway endoscopy (including awake tracheal intubation, nasendoscopy and bronchoscopy) if respirable pathogens cannot be confidently excluded.
10.1111/anae.15968
CoughGAN: Generating Synthetic Coughs that Improve Respiratory Disease Classification
Ramesh Vishwajith,Vatanparvar Korosh,Nemati Ebrahim,Nathan Viswam,Rahman Md Mahbubur,Kuang Jilong
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
Despite the prevalence of respiratory diseases, their diagnosis by clinicians is challenging. Accurately assessing airway sounds requires extensive clinical training and equipment that may not be easily available. Current methods that automate this diagnosis are hindered by their use of features that require pulmonary function tests. We leverage the audio characteristics of coughs to create classifiers that can distinguish common respiratory diseases in adults. Moreover, we build on recent advances in generative adversarial networks to augment our dataset with cleverly engineered synthetic cough samples for each class of major respiratory disease, to balance and increase our dataset size. We experimented on cough samples collected with a smartphone from 45 subjects in a clinic. Our CoughGAN-improved Support Vector Machine and Random Forest models show up to 76% test accuracy and 83% F1 score in classifying subjects' conditions between healthy and three major respiratory diseases. Adding our synthetic coughs improves the performance we can obtain from a relatively small unbalanced healthcare dataset by boosting the accuracy over 30%. Our data augmentation reduces overfitting and discourages the prediction of a single, dominant class. These results highlight the feasibility of automatic, cough-based respiratory disease diagnosis using smartphones or wearables in the wild.
10.1109/EMBC44109.2020.9175597
Clinical assessment of pelvic organ prolapse by consecutive cough maneuver.
International urogynecology journal
INTRODUCTION AND HYPOTHESIS:Staging of pelvic organ prolapse (POP) is important in clinical practice and research. Pelvic organ descent on Valsalva can be confounded by levator co-activation, which may be avoided by assessment on coughing. We evaluated the performance of a three consecutive coughs maneuver in the assessment of POP compared with standardised 6-second Valsalva. METHODS:This was a retrospective observational study carried out in women attending a tertiary urogynaecological service in 2017-2019. Patients underwent a standardised interview and clinical examination. Clinical assessment was performed twice, with both 6-s Valsalva and three consecutive coughs performed in random order. Main outcomes were Ba, C and Bp as defined by Pelvic Organ Prolapse-Quantification (POP-Q). Association between coordinates and prolapse symptoms was investigated with receiver-operating characteristic (ROC) statistics. RESULTS:Datasets of 855 women were analysed. POP symptoms were reported by 447 patients (52%) with a mean bother of 6.1 (SD 3.0). On clinical assessment, relevant prolapse was found in 716 (84%) patients on Valsalva and in 730 (85%) on coughing (p=0.109). Clinically relevant prolapse in the apical compartment was more likely to be detected on Valsalva (p<0.0001). Mean POP-Q measurements were not significantly different between maneuvers, except for Ba (p=0.004). ROC curve analysis yielded an area under the curve of 0.74 (95% CI, 0.70-0.77) for maximum POP-Q stage on Valsalva and 0.72 (95% CI, 0.69-0.75) after three consecutive coughs, with a similar performance of both maneuvers in predicting prolapse symptoms (p=0.95). CONCLUSIONS:Clinical assessment of POP by consecutive coughing seems complementary to standardised Valsalva, especially if Valsalva performance is poor.
10.1007/s00192-022-05208-3
[Cough--diversity and the peripheral mechanisms of production].
Takahama K,Miyata T
Nihon yakurigaku zasshi. Folia pharmacologica Japonica
The physiology and pharmacology of the cough reflex were reviewed from the perspective that the cough response and its peripheral mechanisms have diversity, taking reported findings together with the results obtained from our own studies. It is clear that there was a remarkable difference in the magnitude of expiration and sound in coughing between the two types of coughs in guinea pigs: one is caused by mechanical irritation to the airway mucosa or citric acid inhalation and the other caused by inhalation of pharmacological agents such as capsaicin and substance P. Four types of stimulation, i.e., mechanical, physicochemical, chemical and pharmacological stimulation, were discussed with respect to the site and the mechanisms of action in the airway. Mechanical stimulants and chemical stimulants such as citric acid seem to act mainly on A delta-fibers. However, it is unclear whether pharmacological agents act on C-fibers to produce cough. As to the difference in distribution of cough receptors in the airway, pharmacological differences were found between coughs caused by mechanical irritation on the laryngeal sites and the site of bifurcation of the trachea. Furthermore, capsaicin, applied by a topical spraying method newly developed by us, produced cough-like forced expiration when it was sprayed around the site of the bifurcation of the trachea. This response was not depressed by codeine, but depressed by ophiopogonin, a Chinese herbal antitussive; mephenesine; and a neurokinin A antagonist. Mechanisms of cough augmentation in bronchitic guinea pigs were also described briefly. In conclusion, the site of action of cough stimulants and the mechanisms of cough production are still controversial. To solve these problems, we need to develop new methods and strategies for studying the cough reflex.
[Coughing model by microinjection of citric acid into the larynx in guinea pig].
Tanaka Motomu,Kawamoto Sadanori,Maruyama Kei
Nihon yakurigaku zasshi. Folia pharmacologica Japonica
Many studies of cough were performed under the restrained or anesthetized condition, and coughs were evoked by inhalation of capsaicin or citric acid. Inhalation of irritants induced by "diving response" with apnea and coughs, and these responses induced a change of tidal volume. As a result, respiratory responses are dependent on the inhalation volume. Therefore we developed a new coughing model, and coughs were evoked by microinjection of citric acid into the larynx in the unanesthetized unrestrained guinea pig. Microinjection of 7.5% citric acid (2 microliters/30 s, 5 min) induced coughs (27.03 +/- 4.03 coughs/10 min), and citric acid-induced responses were stable independent of the inhalation volume. In the inhalation studies, animals were exposed to citric acid only once because induced-responses were remarkably decreased by repeated administration at an interval of 24 h. However in our coughing model it was possible to repeatedly challenge the animals by microinjection of citric acid at intervals of 24 h. Microinjection of citric acid into the larynx induced coughs in Sprague-Dawley rats, but inhalation of citric acid did not induce cough. These results indicate that this coughing model is highly sensitive and correctly assessed cough responses.
[Chronic cough in children--what to consider and how to evaluate?].
Iseli P
Praxis
There is a long list of differential diagnoses for chronic cough lasting longer than 4 weeks in children. Diagnostic work up starts with a detailed history taking and a clinical investigation followed by a chest X-ray (in one plane) and a spirometry. For the latter reliable results can be achieved by children older then 5 years. If the diagnostic work up is still inconclusive and if the child is in good clinical condition, a 4 weeks' course of inhalation therapy with steroids and betamimetics together with a 2 weeks' course of antibiotics with a macrolide is warranted. In case coughing persists a thorough diagnostic work up is indicated to rule out conditions like cystic fibrosis, relevant humoral immuno-deficiencies, primary ciliary dyskinesia, anatomic malformation or chronic pulmonary aspiration, preferably done by a pediatric pulmonologist. Chronic cough has to be considered abnormal in any child under the age of 1 year. For this age group a final diagnosis is of special importance.
10.1024/1661-8157.98.23.1367
Airway dynamics, oesophageal pressure and cough.
Lavietes M H,Smeltzer S C,Cook S D,Modak R M,Smaldone G C
The European respiratory journal
This study hypothesizes that: peak supramaximal airflow during cough reflects expiratory muscle effort, and that expiratory muscle function during cough might be assessed from the airflow signal alone. We monitored airflow and oesophageal pressure (Poes) in normal subjects during cough generated under two conditions: 1) voluntarily from functional residual capacity (FRC); and 2) involuntarily after inhalation of citric acid (CA). Maximal expiratory cough flow was quantified as the quotient of maximal flow during a given cough divided by maximal flow at the matched volume of thoracic gas (Vtg) as identified on the maximal expiratory flow-volume curve. We found: flow ratios correlated poorly with Poes; the variance of flow ratios associated with a series of voluntary coughs was poorly explained by Poes. During CA inhalation, when the Vtg compressed during cough could not be controlled, correlation of Poes with flow ratio remained poor. We conclude that to study the motor limb of the cough reflex, measurements of both airflow and oesophageal pressure are required.
Characterization of Ethyl Butyrate-Induced Cough Before and After Breath Control Techniques in Healthy Adults.
American journal of speech-language pathology
PURPOSE:Methods for cough elicitation frequently involve aerosolized tussive agents. Here, we sought to determine whether healthy individuals demonstrate a quantifiable cough response after inhaling a volatile ester and if breath control techniques modify this chemically induced cough response. METHOD:Sixty adult male and female participants inhaled prepared liquid dilutions of ethyl butyrate dissolved in paraffin oil at 20%, 40%, and 60% v/v concentrations in triplicate, with presentation order randomized. We delivered stimuli through a face mask connected to an olfactometer and respiratory pneumotachograph. Participants rated sensations of their urge to cough and pleasantness of the odor while cough airflow was measured. Following baseline testing, participants were randomized to implement pursed-lip breathing or slow-paced breathing after inhaling ethyl butyrate to determine the effects of breath control on cough measures. RESULTS:Inhaled ethyl butyrate elicited cough in 70% of participants. Higher concentrations of ethyl butyrate resulted in significantly greater sensation of the urge to cough, (2, 80) = 10.72, < .001, and significantly more generated coughs, (2, 63) = 13.14, < .001. Compared to baseline, participants rated significantly decreased urge to cough during breath control techniques, (1, 40) = 11.01, = .0019. No significant changes were observed in the number of generated coughs between baseline and breath control techniques, (1, 31) = 7.23, = .01. CONCLUSIONS:Airborne ethyl butyrate is a tussigenic agent in humans. Our findings provide opportunities for future research directions in normal and disordered cough responses to volatile compounds.
10.1044/2022_AJSLP-22-00233
Comparative Antitussive Effects of Medicinal Plants and Their Constituents.
Saadat Saeideh,Shakeri Farzaneh,Boskabady Mohammad Hossein
Alternative therapies in health and medicine
CONTEXT:The cough is a protective reflex, with 2 types, one being more sensitive to mechanical stimulation and the other to chemical stimulation, such as sulfur dioxide, ammonia, citric acid, and capsaicin. Some evidence is available that suppressant therapy is most effective when used for the short-term reduction of coughing. Today, use of herbal drugs is increasing all over the world for various ailments, including to provide antitussive activity. OBJECTIVE:The study intended to review the antitussive effects of various extracts, some fractions, and some constituents of the studied medicinal plants. DESIGN:Various databases, including the Medline, Science Direct, Scopus, and Google Scholar, were searched for studies published between 1978 and 2015, using the keywords antitussive and cough and the names of various medicinal plants and their constituents. SETTING:The study took place in the districts related to Mashhad University of Medical Sciences (Mashhad, Iran). OUTCOME MEASURES:The antitussive effects of medicinal plants and their constituents were normalized to 50 mg/kg and 1 mg/mL against various cough stimulants and compared. RESULTS:The most potent antitussive effect was observed for Nigella sativa and Linum usitatissimum on coughs induced by sulfur dioxide. Artemisia absinthium showed a higher antitussive effect on cough induced by ammonia compared with the other studied medicinal plants. The antitussive effects of Cuminum cyminum and Glycyrrhiza glabra were more potent on cough induced by citric acid than other medicinal plants. CONCLUSIONS:These results suggest the therapeutic potential of the studied medicinal plants as antitussive therapies. However, only a few clinical studies have examined the antitussive effects of medicinal plants, and more clinical studies are needed. The underlying mechanisms of the antitussive effects of medicinal plants should be also examined in further studies.
Future directions in the clinical management of cough: ACCP evidence-based clinical practice guidelines.
Boulet Louis-Philippe
Chest
OBJECTIVES:To impart a call for further research into the identified domains of particular interest in the etiology, management, and treatment of cough. DESIGN/METHODOLOGY:A literature review was performed using the search term "cough" in PubMed between 1983 and 2004. The final draft of this guideline was reviewed, in addition to recent studies on cough, and suggestions provided by the authors were collated into a definitive inventory of specific areas in which the lack of quality evidence encumbered the development of clinically relevant evidence-based recommendations. RESULTS/CONCLUSIONS:Although our understanding of the causes and optimal management of chronic cough have significantly increased over the past 25 years, further research remains to be done on this common symptom. This is reflected by the generally low level of evidence for many of the recommendations in these guidelines. Research is particularly needed on the optimal treatment of postinfectious cough, how to distinguish acute bronchitis from other conditions, how to reliably diagnose and treat cough due to gastroesophageal reflux disease, clearly identifying a role for nonpharmacologic protussive treatment modalities in diseases associated with an increased production of bronchial secretions, determining how often cough in patients with interstitial lung disease is due to conditions other than these, establishing the spectrum and frequency of causes of chronic cough in the immunocompromised hosts, and better characterizing psychogenic cough. Further studies are also needed on methods for the assessment of cough, in particular, noninvasive measures of airway inflammation, and pharmacotherapy. It should be determined how often unexplained cough (previously referred to as idiopathic cough) is due to the use of non-evidence-based guidelines or to environmental causes, and assessed whether an empiric, integrative approach of diagnosing chronic cough leads to better outcomes, including cost-effectiveness, than routine testing. While much work has been done on chronic cough, we need studies on the spectrum and frequency of acute and subacute coughs.
10.1378/chest.129.1_suppl.287S
Longitudinal Cough Frequency Monitoring in Persistent Coughers: Daily Variability and Predictability.
Lung
PURPOSE:We determined the cough counts and their variability in subjects with persistent cough for 30 days. METHODS:The Hyfe cough tracker app uses the mobile phone microphone to monitor sounds and recognizes cough with artificial intelligence-enabled algorithms. We analyzed the daily cough counts including the daily predictability rates of 97 individuals who monitored their coughs over 30 days and had a daily cough rate of at least 5 coughs per hour. RESULTS:The mean (median) daily cough rates varied from 6.5 to 182 (6.2 to 160) coughs per hour, with standard deviations (interquartile ranges) varying from 0.99 to 124 (1.30 to 207) coughs per hour among all subjects. There was a positive association between cough rate and variability, as subjects with higher mean cough rates (OLS) have larger standard deviations. The accuracy of any given day for predicting all 30 days is the One Day Predictability for that day, defined as the percentage of days when cough frequencies fall within that day's 95% confidence interval. Overall Predictability was the mean of the 30-One Day Predictability percentages and ranged from 95% (best predictability) to 30% (least predictability). CONCLUSION:There is substantial within-day and day-to-day variability for each subject with persistent cough recorded over 30 days. If confirmed in future studies, the clinical significance and the impact on the use of cough counts as a primary end-point of cough interventions of this variability need to be assessed.
10.1007/s00408-024-00734-x
Use of electromyographic signals for characterization of voluntary coughing in humans with and without spinal cord injury-A systematic review.
Macedo Felipe Soares,da Rocha Adson Ferreira,Miosso Cristiano Jacques,Mateus Sergio Ricardo Menezes
Physiotherapy research international : the journal for researchers and clinicians in physical therapy
INTRODUCTION:Individuals with spinal cord injury (SCI) frequently have an ineffective cough ability due to dysfunctions in expiratory muscles. In such cases, several articles have reported the occurrence of residual muscular activity in muscles that are accessory to coughing. The knowledge about this activity may be useful for building cough assistance devices. The goal of this review is to investigate and to describe the electromyographic signals generated during voluntary coughing in healthy people and in patients with SCI. METHODS:Two researchers performed, blindly and independently, a systematic review of the following databases: PubMed, PEDro, LILACS, and Science Direct. We conducted the searches using descriptors in English, Portuguese, and Spanish, with no limitations regarding the publication year. The review included articles describing experiments performed in humans and with the use of electromyographic signals in the analysis of voluntary coughing. RESULTS:Among the 156 initially found articles, only nine had results that described the study of electromyographic signals associated with voluntary coughing. The results showed evidence that, during voluntary coughing, electromyographic signals are generated both in expiratory and accessory muscles in healthy subjects. In individuals with SCI below the 5th cervical level (C5), the electromyographic signal appeared only in the clavicular portion of the pectoralis major, especially in the explosive cough phase. CONCLUSION:Our evaluation of the current literature shows that, according to the analysed studies, the electromyographic signals are more pre-eminent in the expiratory phase of the pectoralis major, during voluntary cough of individuals with SCI (C5-T12).
10.1002/pri.1761
Intractable cough associated with the supine body position. Effective therapy with nasal CPAP.
Bonnet R,Jörres R,Downey R,Hein H,Magnussen H
Chest
We describe five patients with severe nocturnal cough and daytime somnolence in whom the coughing attacks are triggered by assuming the supine body position. Quantity and quality of the nocturnal cough were evaluated in the sleep laboratory with and without nasal continuous positive airway pressure (N-CPAP). Air flow characteristics were assessed using flow volume and airway resistance loops. Airway anatomy was evaluated bronchoscopically. In all five patients, the cough had a barking quality. Flow-volume loops showed an expiratory collapse phenomenon in two of the patients. Endoscopically, all five patients had signs of airway collapse. All patients had difficulty falling asleep because of coughing and were awakened by it frequently. Sleep times ranged from 2.5 to 4.5 h per night. With N-CPAP pressures ranging from 5 to 13 cm H2O, all five patients had clinically significant improvement in their symptoms. Their sleep times increased to a range of 5 to 7.5 h per night and the daytime somnolence markedly improved or resolved. All five patients requested a N-CPAP unit for home use. We conclude that a cough that is predominantly associated with or exacerbated by the supine body position may be treated effectively with N-CPAP.
10.1378/chest.108.2.581
Acute cough in the elderly: aetiology, diagnosis and therapy.
Drugs & aging
Although the frequency of physician consultations and the sale of over-the-counter remedies establish the high prevalence of acute cough in the elderly, epidemiological studies have tended to be imprecise. However, respiratory tract infections in nose, larynx and/or bronchi, either viral or bacterial or both, are by far the commonest cause of acute cough. These are especially frequent and hazardous in the elderly, and community living and institutionalisation may aggravate this problem. A variety of viruses and bacteria have been incriminated, with rhinovirus, influenza and respiratory syncytial viruses, and Streptococcus pneumoniae, Haemophilus influenza and Bordetella pertussis being especially important. Viral infections can readily lead to community-acquired pneumonia. Successful diagnosis should point to successful treatment, and in this respect clinical examination and patient history are paramount, supplemented by chest X-ray, viral and bacterial culture and serological testing. Depending on the results of these tests, specific antibacterial therapy may be called for, although there is dispute as to the merits of antibacterial therapy in cases of uncertain diagnosis. Prevention and prophylaxis for influenza and S. pneumoniae infections are now commendably routine in the elderly, especially those in communities. Treatment, as well as the use of antibacterials, may also be directed against the inflammatory and infective processes in the airways. Non-specific antitussive therapy is common and usually highly desirable to prevent the adverse effects of repeated coughing. There have been few advances in antitussive therapy in recent years, opioids and dextromethorphan being the most commonly used agents; they act centrally on the brainstem, but also have a large placebo effect. However they work, they are much appreciated by patients and their partners. Moreover, striking advances in our understanding of the peripheral sensory and central nervous pathways of the cough reflex in recent years should soon lead to a new and more specific choice of agents to inhibit cough.
10.2165/00002512-200421040-00003
A longitudinal assessment of acute cough.
Lee Kai K,Matos Sergio,Evans David H,White Patrick,Pavord Ian D,Birring Surinder S
American journal of respiratory and critical care medicine
RATIONALE:Cough can be assessed with visual analog scales (VAS), health status measures, and 24-hour cough frequency monitors (CF(24)). Evidence for their measurement properties in acute cough caused by upper respiratory tract infection (URTI) and longitudinal data is limited. OBJECTIVES:To assess cough longitudinally in URTI with subjective and objective outcome measures and determine sample size for future studies. METHODS:Thirty-three previously healthy subjects with URTI completed cough VAS, Leicester Cough Questionnaire (LCQ-acute), and CF(24) monitoring (Leicester Cough Monitor) on three occasions, 4 days apart. Changes in subjects' condition were assessed with a global rating of change questionnaire. The potential for baseline first-hour cough frequency (CF(1)), VAS, and LCQ to identify low CF(24) was assessed. MEASUREMENTS AND MAIN RESULTS:Mean ± SD duration of cough at visit 1 was 4.1 ± 2.5 days. Geometric mean ± log SD baseline CF(24) and median (interquartile range) cough bouts were high (14.9 ± 0.4 coughs/h and 85 [39-195] bouts/24 h). Health status was severely impaired. There was a significant reduction in CF(24) and VAS, and improvement in LCQ, from visits 1-3. At visit 3, CF(24) remained above normal limits in 52% of subjects. The smallest changes in CF(24), LCQ, and VAS that subjects perceived important were 54%, 2- and 17-mm change from baseline, respectively. The sample sizes required for parallel group studies to detect these changes are 27, 51, and 25 subjects per group, respectively. CF(1) (<20.5 coughs/h) was predictive of low CF(24). CONCLUSIONS:CF(24), VAS, and LCQ are responsive outcome tools for the assessment of acute cough. The smallest change in cough frequency perceived important by subjects is 54%. The sample sizes required for future studies are modest and achievable.
10.1164/rccm.201209-1686OC
Dissociation in the effect of nedocromil on mannitol-induced cough or bronchoconstriction in asthmatic subjects.
Koskela Heikki O,Martens Ruth,Brannan John D,Anderson Sandra D,Leuppi Joerg,Chan Hak-Kim
Respirology (Carlton, Vic.)
OBJECTIVE:Inhaled mannitol induces both bronchoconstriction and cough. Nedocromil sodium greatly attenuates mannitol-induced bronchoconstriction. Knowledge about the effect of nedocromil on mannitol-provoked cough might, therefore, clarify the mechanisms of this response. METHODOLOGY:Inhalation challenges with mannitol powder were performed after inhalation of 8 mg of nedocromil or its placebo in 24 subjects with asthma. The study was double-blind, randomised, and placebo-controlled. The mannitol-provoked coughs were manually recorded and the mannitol-induced bronchoconstriction was measured with a spirometer. RESULTS:The cumulative dose of mannitol that provoked at least two coughs tended to be higher on the nedocromil day than on the placebo day (34 (22--53) mg vs 26 (18--37) mg, P=0.051). The cumulative number of coughs per dose of mannitol was slightly, but significantly, lower on the nedocromil than on the placebo day (4.2 (2.8--6.3) coughs/100 mg vs 6.1 (4.0--9.4) coughs/100 mg, P=0.037). However, when analysed on a constant-dose basis, nedocromil provided no protection for coughing (-1% protection), whereas the protection for bronchoconstriction was clear (55% protection). CONCLUSIONS:Nedocromil strongly attenuates mannitol-induced bronchoconstriction but has a negligible effect on mannitol-provoked cough. Therefore, these responses seem to have different pathways in asthma. Recording of both provoked coughs and induced bronchoconstriction during mannitol challenge may provide supplementary information about a patient's disease.
10.1111/j.1440-1843.2005.00724.x
Advances in understanding and treatment of cough.
Widdicombe J G
Monaldi archives for chest disease = Archivio Monaldi per le malattie del torace
Many different conditions and diseases cause cough. The commonest acute causes are pollution, including cigarette smoke, and upper respiratory tract infection. The commonest chronic causes are postnasal drip, asthma, chronic bronchitis and gastro-oesophageal reflux. Epidemiological studies give widely different patterns of incidence. The different conditions that cause cough have in common the fact that the cough is mediated via the vagus nerves, with sensory receptors in and under the epithelium from the larynx down to the smaller bronchi. These receptors are polymodal, responding to a large variety of stimuli, including mechanical and chemical irritants, inflammatory mediators, intraluminal material and large volume changes of the lungs. With irritation and inflammation, C fibre receptors release neurokinins such as substance P, which in turn stimulate cough receptors. The central nervous pathways for the cough reflex are poorly understood. They can be activated or inhibited voluntarily. Studies on the pharmacology of the central nervous pathways of coughing are opening up new therapeutic possibilities. Other new therapies include drugs acting on the sensory receptors for cough, thereby avoiding adverse central nervous effects.
Ambulatory methods for recording cough.
Smith Jaclyn
Pulmonary pharmacology & therapeutics
Recording cough sounds to objectively quantify coughing was first performed using large reel-to-reel tape recorders more than 40 years ago. Coughs were counted manually, which is an extremely laborious and time-consuming process. Current technologies including digital recording techniques, data compression and improvements in digital storage capacity should make the process of recording and counting coughs suitable for automation; however, to date no accurate, objective cough monitoring device is available. Cough sounds are easily distinguishable from other vocalizations by the human ear and hence it is reasonable to assume that coughs sounds should have characteristic, identifying acoustic properties. However, the acoustic features of spontaneously occurring cough sounds are extremely variable. Furthermore, in even the worst cases of cough, the time spent speaking is an order of magnitude greater than the time spent coughing. It follows that even an algorithm that mistakes only a very small proportion of speech as cough will still have an unacceptable false positive rate. There is a clear need for an objective measure of cough for use in clinical practice, clinical research and trials of novel treatments. In the near future automated ambulatory systems with sufficient accuracy to be of clinical use should be available.
10.1016/j.pupt.2006.10.016
TBscreen: A passive cough classifier for tuberculosis screening with a controlled dataset.
Science advances
Recent respiratory disease screening studies suggest promising performance of cough classifiers, but potential biases in model training and dataset quality preclude robust conclusions. To examine tuberculosis (TB) cough diagnostic features, we enrolled subjects with pulmonary TB ( = 149) and controls with other respiratory illnesses ( = 46) in Nairobi. We collected a dataset with 33,000 passive coughs and 1600 forced coughs in a controlled setting with similar demographics. We trained a ResNet18-based cough classifier using images of passive cough scalogram as input and obtained a fivefold cross-validation sensitivity of 0.70 (±0.11 SD). The smartphone-based model had better performance in subjects with higher bacterial load {receiver operating characteristic-area under the curve (ROC-AUC): 0.87 [95% confidence interval (CI): 0.87 to 0.88], < 0.001} or lung cavities [ROC-AUC: 0.89 (95% CI: 0.88 to 0.89), < 0.001]. Overall, our data suggest that passive cough features distinguish TB from non-TB subjects and are associated with bacterial burden and disease severity.
10.1126/sciadv.adi0282
A new method for objectively evaluating nocturnal cough in adults.
Respiratory investigation
BACKGROUND:For the management of cough diseases in adults, an objective method of evaluating nocturnal cough is required. METHODS:In Study 1, a cough monitoring system was evaluated using 25 adult volunteers. In Study 2, the cough monitoring system was validated using 20 samples from 10 adult patients with cough diseases obtained overnight. In hospitalized patients, our original cough monitoring system with a microphone and accelerometer was used. At the same time, coughs were recorded using a video camera with digital sound recording. The number of coughs in each 8-h video-audio recording was counted manually by three trained observers. All cough data were printed out, and the basal number of cough events, using both the printed-out data and video-audio recordings, were then calculated by three observers. RESULTS:In Study 1, the cough monitoring system demonstrated good agreement with the number of coughs counted by examiners (sensitivity 99.2%, specificity 98.9%). In Study 2, there was significant agreement in the counts of natural coughs between our system and the video-audio method (p < 0.0001) and between our system and the basal cough events (p < 0.0001). CONCLUSIONS:Our method demonstrated excellent agreement with the video-audio recording method in adults and is considered extremely useful for the objective monitoring of overnight cough in adult patients with cough diseases.
10.1016/j.resinv.2021.12.005
[Pathophysiology, diagnostics and therapy of chronic cough: neuronal reflexes and antitussiva].
Dinh Q T,Heck S,Le D D,Bals R,Welte T
Pneumologie (Stuttgart, Germany)
Cough is the number one symptom for patients to visit a physician worldwide. It is an important neuronal reflex which serves to protect the airways from inhaled exogenous microorganisms, thermal and chemical irritants. Moreover, it prevents the airways from mucus retention.The cough reflex is initiated by activation of different cough receptors. These cough receptors can be divided into three groups according to their electrophysiological properties: into the two Aδ-fiber types "rapid-adapting mechanoreceptor" (RAR) and "slow-adapting mechanoreceptor" (SAR), and the C-fiber receptor.The stimulus is detected by cough receptors which conduct the signal to the cerebral cough centre via vagal-sensory neurons. The cough itself is mediated by efferent motoneurons. Hence the cough reflex consists of 5 functionally sequential parts 1: the cough receptors 2, the primary afferent fibres of the N. vagus 345, N. trigeminus and N. glossopharyngeus 1, the cough centre in the medulla oblongata (N. tractus solitarius) 678, the afferent fibres of the N. phrenicus, spinal nerve and N. laryngeus recurrens, as well as the diaphragm and the abdominal, intercostal and laryngeal muscles. The cough receptors are mainly located in the larynx, trachea and main bronchi 2.The event of coughing can be divided into four subsequent parts: After the first phase of fast inspiration with an opened glottis, there is compression with a closed glottis and increasing tracheal pressure, acceleration and ultimately maximum expiration with an opened glottis 9. According to its characteristics, cough can be split into two distinct types, "aspiration cough", which is loud and involuntary, and "urge-to-cough sensation", which describes an irritant, scratchy, and controlled cough of slowly increasing intensity 10.Acute cough mostly develops because of infection of the respiratory system 111213 and ends spontaneously after 4 weeks. In contrast to this, bacterial infection with pathogens like Adenovirus, Bordetella pertussis and Mycoplasms can last up to 8 weeks 121314. In additional to the division of cough according to its cause, it can also be differentiated according to its manner: dry and mucus-producing cough.With this review we want to give an overview of neuronal processes and mechanisms, as well as diagnostics of and therapy for chronic cough. Thereby the focus is also placed on the efficiency of already established and potential future antitussive agents.
10.1055/s-0033-1343151
Volitional control of reflex cough.
Hegland Karen W,Bolser Donald C,Davenport Paul W
Journal of applied physiology (Bethesda, Md. : 1985)
Multiple studies suggest a role for the cerebral cortex in the generation of reflex cough in awake humans. Reflex cough is preceded by detection of an urge to cough; strokes specifically within the cerebral cortex can affect parameters of reflex cough, and reflex cough can be voluntarily suppressed. However, it is not known to what extent healthy, awake humans can volitionally modulate the cough reflex, aside from suppression. The aims of this study were to determine whether conscious humans can volitionally modify their reflexive cough and, if so, to determine what parameters of the cough waveform and corresponding muscle activity can be modified. Twenty adults (18-40 yr, 4 men) volunteered for study participation and gave verbal and written informed consent. Participants were seated and outfitted with a facemask and pneumotacograph, and two surface EMG electrodes were positioned over expiratory muscles. Capsaicin (200 μM) was delivered via dosimeter and one-way (inspiratory) valve attached to a side port between the facemask and pneumotachograph. Cough airflow and surface EMG activity were recorded across tasks including 1) baseline, 2) small cough (cough smaller or softer than normal), 3) long cough (cough longer or louder than normal), and 4) not cough (alternative behavior). All participants coughed in response to 200 μM capsaicin and were able to modify the cough. Variables exhibiting changes include those related to the peak airflow during the expiratory phase. Results demonstrate that it is possible to volitionally modify cough motor output characteristics.
10.1152/japplphysiol.01299.2011
Efficacy of universal masking for source control and personal protection from simulated cough and exhaled aerosols in a room.
Journal of occupational and environmental hygiene
Face masks reduce the expulsion of respiratory aerosols produced during coughs and exhalations ("source control"). Factors such as the directions in which people are facing (orientation) and separation distance also affect aerosol dispersion. However, it is not clear how the combined effects of masking, orientation, and distance affect the exposure of individuals to respiratory aerosols in indoor spaces. We placed a respiratory aerosol simulator ("source") and a breathing simulator ("recipient") in a 3 m × 3 m chamber and measured aerosol concentrations for different combinations of masking, orientation, and separation distance. When the simulators were front-to-front during coughing, masks reduced the 15-min mean aerosol concentration at the recipient by 92% at 0.9 and 1.8 m separation. When the simulators were side-by-side, masks reduced the concentration by 81% at 0.9 m and 78% at 1.8 m. During breathing, masks reduced the aerosol concentration by 66% when front-to-front and 76% when side-by-side at 0.9 m. Similar results were seen at 1.8 m. When the simulators were unmasked, changing the orientations from front-to-front to side-by-side reduced the cough aerosol concentration by 59% at 0.9 m and 60% at 1.8 m. When both simulators were masked, changing the orientations did not significantly change the concentration at either distance during coughing or breathing. Increasing the distance between the simulators from 0.9 m to 1.8 m during coughing reduced the aerosol concentration by 25% when no masks were worn but had little effect when both simulators were masked. During breathing, when neither simulator was masked, increasing the separation reduced the concentration by 13%, which approached significance, while the change was not significant when both source and recipient were masked. Our results show that universal masking reduces exposure to respiratory aerosol particles regardless of the orientation and separation distance between the source and recipient.
10.1080/15459624.2021.1939879
Non-prescription antibiotic use for cough among Chinese children under 5 years of age: a community-based cross-sectional study.
Zhu Yao,Tang Xuewen,Yan Rui,Shao Zhujun,Zhou Yang,Deng Xuan,Luo Shuying,He Hanqing
BMJ open
OBJECTIVE:This study aimed to investigate the non-prescription use of antibiotics for cough among children under 5 years in China. DESIGN:A community-based cross-sectional survey. SETTING:A face-to-face interview based on a standard questionnaire in the community from October to December 2019. PARTICIPANTS:A total of 3102 children under 5 years of age were enrolled with probability proportionate to size sampling method. The children's caregivers provided the responses as their agents. OUTCOME MEASURES:Cough in the past month, non-prescription use of antibiotics after cough. RESULTS:1211 of 3102 children were reported to have a cough in the past month. Of these, 40.2% (487/1211) were medicated with antibiotics, and 18.7% (91/487) of these were not prescribed. Cephalosporins were the most frequently used antibiotic (52.8%), and community pharmacies were the main source (53.7%). Children who coughed for 1-2 weeks (OR 1.73, 95% CI 1.03 to 2.90) or 3-4 weeks (OR 2.39, 95% CI 1.08 to 4.97), with runny nose (OR 1.86, 95% CI 1.13 to 3.19) or those whose family annual income between ¥50 000 and ¥100 000 (OR 4.44, 95% CI 1.52 to 18.95) had a higher risk of non-prescription use of antibiotics than those coughing for <1 week, without runny nose or with family annual income <¥50 000. CONCLUSIONS:Our findings indicated that a high proportion of infants and young children had been treated with antibiotics for cough, and nearly one in five of them were used without prescription. More public health campaigns and further education on the appropriate use of antibiotics are needed to ensure the rational treatment of cough in children.
10.1136/bmjopen-2021-051372
Effect of Tulobuterol Patch Versus Placebo on the Occurrence of Respiratory Adverse Events in Children Undergoing Tonsillectomies: A Randomized Controlled Trial.
Anesthesia and analgesia
BACKGROUND:Perioperative respiratory adverse events are common in children. We aimed to evaluate the effect of the transdermal β-2 agonist, tulobuterol, compared with that of placebo on the incidence of perioperative respiratory adverse events in pediatric patients undergoing tonsillectomy. METHODS:In this triple-blinded (patient, anesthesia provider, and outcome assessor) randomized controlled trial, 188 patients were randomly allocated to receive tulobuterol or a placebo. The tulobuterol groups received a tulobuterol patch (1 mg) masked with a bandage, whereas the placebo only received the bandage. The assigned bandage was applied to the patients 8 to 10 hours before the surgery. The primary outcome was the occurrence of any perioperative respiratory adverse events: oxygen desaturation <95%, airway obstruction, laryngospasm, bronchospasm, severe coughing, or stridor. The outcomes were evaluated using the average relative effect test, which estimates the effect of individual components of a composite outcome and then averages effects across components. RESULTS:A total of 88 and 94 patients who received tulobuterol and placebo, respectively, were analyzed. The incidence of any perioperative respiratory adverse event was lower with tulobuterol (n = 13/88; 14.7%) than that with the placebo (n = 40/94; 42.5%), with an estimated average relative risk (95% confidence interval) across components of 0.35 (0.20-0.60; P < .001). The symptoms of airway obstruction were lower with tulobuterol (n = 8/88; 9.0%) than that with the placebo (n = 32/94; 34.0%), with relative risk (95% CI) of 0.31 (0.17-0.56; P < .001). The occurrence of severe coughing was lower with tulobuterol (n = 1/88; 1.1%) than that with the placebo (n = 8/94; 8.5%), with relative risk (95% CI) of 0.15 (0.03-0.68; P = .014). CONCLUSIONS:In preschool children undergoing tonsillectomy, the preoperative application of a tulobuterol patch could decrease the occurrence of perioperative respiratory adverse events. Further studies are needed to elucidate the effect of the tulobuterol patch in a broad spectrum of pediatric anesthesia.
10.1213/ANE.0000000000006355
Efficacy of endotracheal lidocaine administration with continuous infusion of remifentanil for attenuating tube-induced coughing during emergence from total intravenous anesthesia.
Yamasaki Hiroyuki,Takahashi Kayoko,Yamamoto Shunsuke,Yamamoto Yoko,Miyata Yoshihisa,Terai Takekazu
Journal of anesthesia
PURPOSE:Although attenuation of tube-induced coughing is necessary in specific types of surgery, the best method for such attenuation is still unclear. We studied the combined intervention of endotracheal lidocaine and intravenous remifentanil compared to intravenous remifentanil alone with respect to coughing during emergence from anesthesia. METHODS:We examined 60 ASA 1-2 patients (age, 20-69 years) undergoing tympanoplasty under general anesthesia. Anesthesia was induced with propofol, remifentanil, and rocuronium. The trachea was intubated using a laryngotracheal instillation of topical anaesthetic (LITA) tracheal tube. Anesthesia was maintained with propofol and remifentanil (0.1-0.3 μg/kg/min). Propofol was discontinued and remifentanil (0.1 μg/kg/min) was continued at the end of the operation. Patients were randomly allocated to the lidocaine (n = 30) and control groups (n = 30). We administered 3 ml 4 % lidocaine via the LITA tube to patients in lidocaine group at the end of the operation. The trachea was extubated when the patient regained consciousness and followed orders. Coughing was evaluated using a 4-point scale by an observer who examined the video records at extubation. RESULTS:Fewer patients in lidocaine group (8 of 30) than in control group (18 of 30, p < 0.01) coughed. Fewer patients in lidocaine group (2 of 30) than in control group (12 of 30, p < 0.01) had moderate or severe cough (scale 2 or 3). CONCLUSIONS:This study is consistent with the finding that endotracheal lidocaine administration and continuous infusion of remifentanil before extubation is useful to prevent coughing on emergence from anesthesia.
10.1007/s00540-013-1627-3
Patient preferences for the treatment of chronic cough: a discrete choice experiment.
BMJ open respiratory research
BACKGROUND:Chronic cough is common, negatively affects quality of life and has limited treatment options. Inhibition of purinergic signalling is a promising therapeutic approach but is associated with taste-related adverse effects. Little is known about treatment preferences from the perspective of patients with chronic cough, such as trade-offs between efficacy and side effect. METHODS:Patients with chronic cough completed an online discrete choice experiment survey in which they answered a series of questions requiring a choice between two constructed treatment options characterised by varying attribute levels. Selection of cough and taste-related attributes was informed by qualitative interviews and clinical trial data. Logit-based models were used to analyse resulting choice data. RESULTS:The discrete choice experiment survey was completed by 472 participants with chronic cough. Among study attributes, frequency of intense cough attacks was the most important to participants, followed by taste change, frequency of night-time coughing and frequency of daytime coughing. To accept the least preferred taste disturbance of a bitter, metallic, chalky or oily taste change, participants required either: (1) elimination of night-time cough along with a slight reduction in daytime cough; (2) elimination of daytime cough along with a pronounced reduction in night-time or (3) reduction in intense cough attacks from 7 to 2 times per week. Two distinct preference patterns were identified, each placing different importance on efficacy versus side effect trade-offs. CONCLUSIONS:Participants with chronic cough were willing to accept some taste disturbances in exchange for improved efficacy of chronic cough treatments. Knowledge of patient preferences can facilitate shared decision-making.
10.1136/bmjresp-2023-001888
[Coughing. Pathognomic significance and therapeutic options].
Zanasi Alessandro,Giannuzzi Antonia,Porrino Lorenzo
Recenti progressi in medicina
A wide range of disease processes may present with cough and definitive treatment depends on making an accurate diagnosis of the cause. Acute or short-lived cough, which most commonly occurs in association with viral upper respiratory tract infection, is of a little consequence, usually resolving in a matter of days. The most common chronic causes of cough are post-nasal drip, asthma, gastro-esophageal reflux and chronic bronchitis. The different conditions that cause cough have in common the fact that are mediated by the vagus nerves, with sensory receptors in and under the epithelium from the larynx to the smaller bronchii. The receptors are polymodal, responding to a large variety of stimuli, including mechanical and chemical irritants, inflammatory mediators, intraluminal material and large volume changes of the lung. Intensive treatment of underlying cause usually leads to improvement or resolution of cough. However, in a minority of patients, no underlying cause is identified despite appropriate investigation: in these subjects or when cough interferes with patient's health or sleep is indicated a non specific treatment with antitussive therapy.
Role of triangularis sterni during coughing and sneezing in dogs.
van Lunteren E,Haxhiu M A,Cherniack N S,Arnold J S
Journal of applied physiology (Bethesda, Md. : 1985)
Studies in mammals have found that during breathing the triangularis sterni (TS) muscle regulates expiratory airflow and the end-expiratory position of the rib cage and furthermore that the respiratory activity of this muscle is influenced by a variety of chemical and mechanical stimuli. To assess the role of the TS during coughing and sneezing, electromyograms (EMGs) recorded from the TS were compared with EMGs of the transversus abdominis (TA) in eight pentobarbital-anesthetized dogs. During coughing induced by mechanically stimulating the trachea or larynx (n = 7 dogs), peak EMGs increased from 23 +/- 2 to 74 +/- 5 U (P less than 0.00002) for the TS and from 21 +/- 6 to 66 +/- 4 U (P less than 0.0002) for the TA. During sneezing induced by mechanically stimulating the nasal mucosa (n = 3 dogs), peak EMG of the TS increased from 10 +/- 3 to 66 +/- 7 U (P less than 0.005) and peak EMG of the TA increased from 10 +/- 2 to 73 +/- 7 U (P less than 0.02). For both muscles the shape of the EMG changed to an early peaking form during coughs and sneezes. Peak expiratory airflow during coughs of different intensity correlated more closely with peak TS EMG in three dogs and with peak TA EMG in four dogs; peak expiratory airflow during sneezes of different intensity correlated more closely with peak TS than TA EMG in all three animals. These results suggest that the TS is actively recruited during coughing and sneezing and that different neuromuscular strategies may be utilized to augment expiratory airflow.
10.1152/jappl.1988.65.6.2440
Accumulated oropharyngeal water increases coughing during dental treatment with intravenous sedation.
Kohjitani A,Egusa M,Shimada M,Miyawaki T
Journal of oral rehabilitation
In dental procedures performed under intravenous sedation in patients with intellectual disabilities, procedures are sometimes interrupted by the cough reflex, which may be triggered by intraoral use of water and/or increased secretion stimulating the pharyngeal/laryngeal mucosa, or by those irritating the tracheal mucosa directly through anesthetics-induced impairment of the laryngeal closure reflex. We investigated relationships between frequency of coughing episodes and intraoral use of water, water remaining in the oropharyngeal space, and mean infusion rate of propofol during dental treatments performed under intravenous sedation with midazolam and propofol. Twenty-one intellectually disabled patients were enrolled. After induction, a 14 Fr. suction catheter was inserted nasally, which was fixed where oropharyngeal suction could be done most effectively. Patients were divided into three groups according to the amount of intraoral use of water, amount of oropharyngeal suction and mean infusion rate of propofol. The amount of oropharyngeal suction significantly correlated with intraoral use of water. Frequency of coughing episodes significantly correlated with amount of oropharyngeal suction per minute. However, coughing episodes correlated neither with intraoral use of water nor with infusion rate of propofol. These findings suggested that accumulation of water in the oropharynx increased vulnerability to the cough reflex in dental treatments performed under intravenous sedation.
10.1111/j.1365-2842.2007.01752.x
Fictive cough in the cat.
Bolser D C
Journal of applied physiology (Bethesda, Md. : 1985)
Experiments were performed to determine whether cough could be elicited in paralyzed cats ventilated on a respiratory cycle-triggered pump. Midcollicular decerebrate cats were paralyzed and artificially ventilated on a phrenic-triggered pump. Phrenic and cranial iliohypogastric nerve efferent activities were recorded. Cough was elicited by electrical stimulation of the superior laryngeal nerve (SLN) or probing the intrathoracic trachea. Fictive coughs induced by electrical stimulation of the SLN or mechanical stimulation of the intrathoracic trachea consisted of large-amplitude bursts in phrenic discharge immediately followed by large bursts in cranial iliohypogastric discharge. During fictive cough, phrenic postinspiratory discharge was reduced relative to control cycles. Codeine (0.03-1 mg/kg iv) decreased both SLN- and probe-induced fictive cough. I conclude that fictive cough can be produced in paralyzed cats ventilated on a phrenic-triggered pump. Furthermore, fictive cough can be produced in the absence of afferent feedback associated with active expiration.
10.1152/jappl.1991.71.6.2325
COVID-19 detection in cough, breath and speech using deep transfer learning and bottleneck features.
Computers in biology and medicine
We present an experimental investigation into the effectiveness of transfer learning and bottleneck feature extraction in detecting COVID-19 from audio recordings of cough, breath and speech. This type of screening is non-contact, does not require specialist medical expertise or laboratory facilities and can be deployed on inexpensive consumer hardware such as a smartphone. We use datasets that contain cough, sneeze, speech and other noises, but do not contain COVID-19 labels, to pre-train three deep neural networks: a CNN, an LSTM and a Resnet50. These pre-trained networks are subsequently either fine-tuned using smaller datasets of coughing with COVID-19 labels in the process of transfer learning, or are used as bottleneck feature extractors. Results show that a Resnet50 classifier trained by this transfer learning process delivers optimal or near-optimal performance across all datasets achieving areas under the receiver operating characteristic (ROC AUC) of 0.98, 0.94 and 0.92 respectively for all three sound classes: coughs, breaths and speech. This indicates that coughs carry the strongest COVID-19 signature, followed by breath and speech. Our results also show that applying transfer learning and extracting bottleneck features using the larger datasets without COVID-19 labels led not only to improved performance, but also to a marked reduction in the standard deviation of the classifier AUCs measured over the outer folds during nested cross-validation, indicating better generalisation. We conclude that deep transfer learning and bottleneck feature extraction can improve COVID-19 cough, breath and speech audio classification, yielding automatic COVID-19 detection with a better and more consistent overall performance.
10.1016/j.compbiomed.2021.105153
The role of coughing as a gastroesophageal-reflux provoking maneuver: the scintigraphical evaluation.
Yapici Oktay,Basoglu Tarik,Canbaz Fevziye,Sever Aysen
Nuclear medicine communications
BACKGROUND:Attempts have been made to improve the positivity of the radionuclide detection of gastroesophageal reflux (GER). The aim of this study was to examine the possible contribution of coughing as a provoking maneuver in GER scintigraphy. METHODS:One hundred and twenty-five patients (mean age: 9.2+/-3.2 years) who had a clinical probability of having GER and were fully able to cooperate for coughing on command were included in the study. The patients were asked to cough gently four to six times per minute in the 2nd, 4th, and 6th 10-min periods within a 60-min total study time. The presence and number of GER episodes were noted for each period in all patients. RESULTS:Sixty-one of 125 patients (48.8%) showed no scintigraphic finding of GER and were interpreted as normal. In the remaining 64 patients (51.2%), GER was observed and these patients were interpreted as abnormal (GER+). Among patients with abnormal results, 25 (39%) presented GER episodes only during the coughing intervals of the study. In 33 (51.6%) patients, the reflux was seen both at coughing and noncoughing periods. In only six patients (9.4%) with GER in noncoughing periods, coughing did not provoke any reflux episodes. No overall correlation between cough-provoked frequency of reflux, number of GER episodes, and symptom severity was found in 64 GER+ patients (P>0.5); but in the subgroup of patients presenting GER episodes only during the coughing intervals, 60% (15 of 25), presented GER episodes only in one of the three cough-provoked intervals and also had the lowest symptom severity scores. CONCLUSION:The results of our study showed that 39% (25 of 64) of the observed GER findings were achieved exclusively by means of cough provocation.
10.1097/MNM.0b013e3283298f90
Mechanical Stimulation by Postnasal Drip Evokes Cough.
Iwata Toshiyuki,Ito Isao,Niimi Akio,Ikegami Koji,Marumo Satoshi,Tanabe Naoya,Nakaji Hitoshi,Kanemitsu Yoshihiro,Matsumoto Hisako,Kamei Junzo,Setou Mitsutoshi,Mishima Michiaki
PloS one
Cough affects all individuals at different times, and its economic burden is substantial. Despite these widespread adverse effects, cough research relies on animal models, which hampers our understanding of the fundamental cause of cough. Postnasal drip is speculated to be one of the most frequent causes of chronic cough; however, this is a matter of debate. Here we show that mechanical stimuli by postnasal drip cause chronic cough. We distinguished human cough from sneezes and expiration reflexes by airflow patterns. Cough and sneeze exhibited one-peak and two-peak patterns, respectively, in expiratory airflow, which were also confirmed by animal models of cough and sneeze. Transgenic mice with ciliary dyskinesia coughed substantially and showed postnasal drip in the pharynx; furthermore, their cough was completely inhibited by nasal airway blockade of postnasal drip. We successfully reproduced cough observed in these mice by injecting artificial postnasal drip in wild-type mice. These results demonstrated that mechanical stimulation by postnasal drip evoked cough. The findings of our study can therefore be used to develop new antitussive drugs that prevent the root cause of cough.
10.1371/journal.pone.0141823
Prolonged cough in children: a summary of the Belgian primary care clinical guideline.
Leconte Sophie,Paulus Dominique,Degryse Jan
Primary care respiratory journal : journal of the General Practice Airways Group
Prolonged cough is a frequent problem in the community. Several studies in the school setting have found that as many as 4.8% to 10.4% of children suffer from prolonged cough. There is no consensual definition of prolonged cough. In this guideline, we define prolonged cough as a daily cough lasting for more than three weeks. The literature review did not identify any quality study on the aetiology of prolonged cough in children in primary care. A diagnostic decision-tree based on the systematic literature review and expert opinion is proposed. Doctors should seek signs of any serious underlying condition. Chronic productive purulent cough should always be investigated. A careful evaluation of the impact of cough on the quality of life of the child is necessary. In absence of signs of specific underlying illness, coughing is generally a self-limiting condition. Symptomatic treatments have not yet been proven to be effective, and many of them may cause serious side effects. Their use should therefore be limited.
10.3132/pcrj.2008.00028
[Acute and chronic cough - differential diagnosis and treatment].
Deutsche medizinische Wochenschrift (1946)
Cough is a frequent reason for consultation in the general practitioner's office. Most of the time, the symptom is harmless and self-limiting, as in the case of a banal cold cough, for example - however, serious diseases such as malignancies can also be the cause. Evaluation is therefore not always easy. This article presents a targeted and appropriate approach and discusses which treatments are recommended and effective.Acute and chronic cough are differentiated according to the duration of symptoms (up to 8 weeks/longer than 8 weeks). The most common cause of acute cough is a self-limiting viral infection of the upper respiratory tract; the most important differential diagnosis is community-acquired pneumonia. If there are no defined warning signs (red flags), the history and clinical examination are sufficient to establish the diagnosis in the case of an acute cough; medication is not necessary. In the case of a chronic cough, a chest X-ray is usually ordered and then further investigations are carried out in accordance with the most probable suspected diagnosis; probationary therapies are an important part of the workup. Coughs that are refractory to treatment or unexplained require individualised treatment (pharmacological, including off-label, non-pharmacological) and regular re-evaluation.
10.1055/a-1716-8101
Prevalence of cough throughout childhood: A cohort study.
Jurca Maja,Ramette Alban,Dogaru Cristian M,Goutaki Myrofora,Spycher Ben D,Latzin Philipp,Gaillard Erol A,Kuehni Claudia E
PloS one
BACKGROUND:Cough in children is a common reason for medical consultations and affects quality of life. There are little population-based data on the epidemiology of recurrent cough in children and how this varies by age and sex, or between children with and without wheeze. We determined the prevalence of cough throughout childhood, comparing several standardised cough questions. We did this for the entire population and separately for girls and boys, and for children with and without wheeze. METHODS:In a population-based prospective cohort from Leicestershire, UK, we assessed prevalence of cough with repeated questionnaires from early childhood to adolescence. We asked whether the child usually coughed more than other children, with or without colds, had night-time cough or cough triggered by various factors (triggers, related to increased breathing effort, allergic or food triggers). We calculated prevalence from age 1 to 18 years using generalised estimating equations for all children, and for children with and without wheeze. RESULTS:Of 7670 children, 10% (95% CI 10-11%) coughed more than other children, 69% (69-70%) coughed usually with a cold, 34% to 55% age-dependently coughed without colds, and 25% (25-26%) had night-time cough. Prevalence of coughing more than peers, with colds, at night, and triggered by laughter varied little throughout childhood, while cough without colds and cough triggered by exercise, house dust or pollen became more frequent with age. Cough was more common in boys than in girls in the first decade of life, differences got smaller in early teens and reversed after the age of 14 years. All symptoms were more frequent in children with wheeze. CONCLUSIONS:Prevalence of cough in children varies with age, sex and with the questions used to assess it, suggesting that comparisons between studies are only valid for similar questions and age groups.
10.1371/journal.pone.0177485
Health seeking behavior and associated factors among individuals with cough in Yiwu, China: a population-based study.
Sun Xiaoyan,Luo Shuying,Lou Lingqiao,Cheng Hang,Ye Zhen,Jia Jianwei,Wei Yina,Tao Jingbo,He Hanqing
BMC public health
BACKGROUND:Previous studies have shown that a certain proportion of the population did not seek medical treatment after coughing, and understanding the potential reasons is crucial for disease prevention and control. METHOD:A population-based study was conducted with the probability proportional to population size sampling in Yiwu, Zhejiang, China. A total of 5855 individuals aged ≥15 years lived in Yiwu for more than 6 months were included. All participants completed a laptop-based questionnaire to collect detailed information by a face-to-face interview. Characteristics of individuals were described by categories of health seeking behavior using frequency and percentage. Univariate and multivariate logistic regression analyses were performed to estimate the associations of social-demographic and cough characteristics with health seeking behavior. RESULTS:19.3% (1129/5855) of participants had a cough in the past month, 40% (452/1129) had sought medical treatment. Of these, 26.5% (120/452) chose hospitals at county level or above. Individuals aged ≥65 years old (OR = 2.25, 95% CI: 1.23, 4.12), female (OR = 1.57, 95% CI: 1.21, 2.06), living in rural areas (OR = 1.30, 95% CI: 1.003, 1.69), persistent cough for 3-8 weeks (OR = 2.91, 95% CI: 1.72, 4.92) and with more accompanying symptoms (P < 0.001) were more likely to seek medical treatment, but those coughed for > 8 weeks were not (p > 0.5). Female (OR = 0.33, 95% CI: 0.21, 0.54) and people living in rural areas (OR = 0.57, 95% CI: 0.36, 0.92) were less likely to choose hospitals at county level or above while the higher educated were more likely to (OR = 3.29, 95% CI: 1.35, 8.02). Those who coughed for more than 2 weeks were more likely to choose hospitals at or above the county level. But the number of accompanying symptoms does not show any significant relationship with the choice of medical facility. CONCLUSION:The present study found that age, sex, living areas and features of cough were associated with health seeking behavior. It is worth noting that those who coughed for too long (e.g. > 8 weeks) were less likely to seek medical treatment. Targeted measures should be developed based on the key factors found in this study to guide persons to seek medical treatment more scientifically.
10.1186/s12889-021-11250-5
Comparison of intravenous and topical lidocaine as a suppressant of coughing after bronchoscopy during general anesthesia.
Jakobsen C J,Ahlburg P,Holdgård H O,Olsen K H,Thomsen A
Acta anaesthesiologica Scandinavica
Twenty-four consecutive patients scheduled for fiberbronchoscopy were randomized to receive double-blind either intravenous (1.5 mg/kg) or laryngotracheal (3 mg/kg) lidocaine to evaluate the influence on post-bronchoscopic laryngospasm, pain in the throat and coughing. Plasma lidocaine concentrations were analyzed 5, 15, 30 and 60 min after administration. None of the patients demonstrated laryngospasm or pain in the throat during the first hour after bronchoscopy. Patients receiving topical lidocaine coughed significantly more than patients receiving intravenous lidocaine, with a median number of coughs of 20 compared to 4, during the first hour (P less than 0.01). The plasma lidocaine concentrations were significantly higher after intravenous than after topical administration (P less than 0.001). After intravenous administration the plasma lidocaine concentrations exceeded the accepted level for potential toxicity in five out of 11 patients, but none of the patients developed toxic symptoms and no side-effects were observed.
Swallowing action immediately before intravenous fentanyl at induction of anesthesia prevents fentanyl-induced coughing: a randomized controlled study.
Sako Saori,Tokunaga Shoji,Tsukamoto Masanori,Yoshino Jun,Fujimura Naoyuki,Yokoyama Takeshi
Journal of anesthesia
PURPOSE:Fentanyl is a strong µ-opioid analgesic which attenuates the stimulation of surgical invasion and tracheal intubation. However, intravenous fentanyl often induces coughing [fentanyl-induced coughing (FIC)] during induction of anesthesia. We found that the swallowing action, when requested at induction of anesthesia, attenuated FIC. In the current study, we investigated the relationship between the occurrence of FIC and the swallowing action. METHODS:The study included American Society of Anesthesiologists physical status I or II patients, aged 20-64 years, who were undergoing elective surgery. They were divided into two groups-one group was urged to perform the swallowing action immediately before intravenous fentanyl (S group), and the other group performed no swallowing action (non-S group). The patients first received intravenous fentanyl and were observed for 90 s. Each patient's background, dose of fentanyl and occurrence of coughing were investigated from their records and a motion picture recording. The incidence of FIC was evaluated by chi-squared test, and severity was tested by Wilcoxon rank-sum test. P < 0.05 was considered statistically significant. RESULTS:The incidence of FIC in the S group and non-S group was 14.0 and 40.4%, respectively. The risk of FIC was reduced in the S group by 75%; risk ratio (95% confidence interval) was 0.35 (0.20, 0.60). The number of coughs in the S group were less than in the non-S group (P < 0.001). CONCLUSION:The swallowing action immediately before intravenous fentanyl may be a simple and clinically feasible method for preventing FIC effectively. Clinical trial number: UMIN000012086 ( https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=Rn000014126&language=J ).
10.1007/s00540-016-2300-4
An objective evaluation of nocturnal cough count and cough pattern in children with psychogenic cough.
Imai Eri,Hirai Kota,Mikami Yoshiko,Nukaga Mariko,Enseki Mayumi,Tabata Hideyuki,Kato Masahiko,Mochizuki Hiroyuki
Respiratory investigation
Two patients with a chronic, barking cough were diagnosed with psychogenic cough. Using an original cough counter we studied the nocturnal cough count and pattern. While the number of coughs when awake was extremely high for both patients, the number of coughs was remarkably reduced during sleep, similar to an exacerbation of asthma. Moreover, the properties of the coughs when awake were clearly different from those of coughs during sleep. In conclusion, an objective examination using a cough counter was useful for the diagnosis, treatment and management of psychogenic cough.
10.1016/j.resinv.2017.08.008
Acoustic Analysis of Voluntary Coughs, Throat Clearings, and Induced Reflexive Coughs in a Healthy Population.
Dysphagia
Cough efficacy is considered a reliable predictor of the aspiration risk in head and neck cancer patients with radiation-associated dysphagia. Currently, coughing is assessed perceptually or aerodynamically. The goal of our research is to develop methods of acoustic cough analysis. In this study, we examined in a healthy population the acoustical differences between three protective maneuvers: voluntary cough, voluntary throat clearing, and induced reflexive cough. Forty healthy participants were included in this study. Voluntary cough, voluntary throat clearing, and reflexive cough samples were recorded and analyzed acoustically. Temporal acoustic features were the following: the slope and curvature of the amplitude contour, as well as the average, slope, and curvature of the sample entropy and kurtosis contours of the recorded signal. Spectral features were the relative energy in the frequency bands (0-400 Hz, 400-800 Hz, 800-1600 Hz, 1600 Hz-3200 Hz, > 3200 Hz) as well as the weighted spectral energy. Results showed that, compared to a voluntary cough, a throat clearing starts with a weaker onset pulse and involves oscillations from the onset to the offset (concave curvature of the amplitude contour, p < 0.05), lower average (p < 0.05), and slope (p < 0.05) as well as lower convex curvature (p < 0.05) of the kurtosis contour. An induced reflexive cough starts with a higher and briefer onset burst and includes higher frication noise (larger convexity of the curvature of the amplitude and kurtosis contours (p < 0.05)) compared to a voluntary cough. The conclusion is that voluntary coughs are acoustically significantly different from voluntary throat clearings and induced reflexive coughs.
10.1007/s00455-023-10574-1
Updates in treatment of adults with chronic cough.
On Phung C
The American journal of managed care
Chronic cough is a severely debilitating condition that results in individuals coughing hundreds to thousands of times per day. Unfortunately, at the time of this writing, the majority of treatments currently available address acute cough and have minimal efficacy for chronic cough. There are no current FDA-approved pharmacologic treatments for chronic cough, resulting in a large, unmet need for patients. Recent advancements in the understanding of the chronic cough reflex and suspected neurobiology have led to the development of novel therapeutic targets to bridge this unmet treatment need. Current American College of Chest Physicians and European guidelines recommend a thorough workup but differ in individual pharmacologic treatment recommendations. All patients should be evaluated for red-flag symptoms and any underlying conditions that may explain the patient's chronic cough. Historical treatments, such as opiates and neuromodulators, have been used with limited success. Emerging agents that target specific channel receptors have shown initial positive benefits concerning cough frequency, severity, and quality of life and may become available on the market as they have shown to be generally well tolerated without any safety concerns in clinical studies.
10.37765/ajmc.2020.88515
The effects of lung volume recruitment on coughing and pulmonary function in patients with ALS.
Cleary Stuart,Misiaszek John E,Kalra Sanjay,Wheeler Sonya,Johnston Wendy
Amyotrophic lateral sclerosis & frontotemporal degeneration
Our objective was to study the intensity and duration of the effects of lung volume recruitment, a manual breath stacking technique, on pulmonary function and coughing in individuals with amyotrophic lateral sclerosis (ALS). Twenty-nine individuals with ALS participated in this study. A cross-over research design was used to compare effects of lung volume recruitment to a control condition. Treatment outcome measures included forced vital capacity (FVC), sniff nasal pressure (SnP) and peak cough flow (PCF). Results demonstrated that LVR had a significantly positive effect on FVC for up to 15 min following treatment but did not have a facilitative effect on SnP at any time-point. LVR had a significantly positive effect on PCF during unassisted coughing at both 15 min and 30 min following treatment, and there was no significant decrease in flow rates from baseline to 30 min later. In conclusion, lung volume recruitment may be an effective treatment for improving coughing and pulmonary function in individuals with ALS. Future research should be focused on determining patient characteristics that contribute to response to treatment, as well as randomized controlled trials of the technique.
10.3109/17482968.2012.720262
Cerebrospinal fluid pressure changes in response to coughing.
Williams B
Brain : a journal of neurology
CSF pressure recordings have been taken from the lumbar region and the cisterna magna of 16 patients during coughing in the sitting position. Isolated coughs of low amplitude have been studied. The lumbar pressure waves occur sooner and lower. Thus there is a phase during which the lumbar pressure exceeds the cisternal, followed by one in which the cisternal exceeds the lumbar. These phenomena may be conveniently displayed on a differential trace. The phase during which the cisternal pressure exceeds the lumbar may be protracted. It is suggested that Froin's syndrome, central subarachnoid pouches and syringobulbia may be associated with upward pressure waves. Cough headache, the filling stages of communicating syringomyelia and tonsillar herniation may be associated with valve-like blockage at the foramen magnum which produces craniospinal pressure dissociation by interfering with downward or rebound pulsation. Decompensation of hydrocephalus after birth may be related to pulsation in association with crying; also after removal of a meningocele sac decompensation may be related to the effects of similar pulsation modified by changes in capacitance following operation. The cord destruction of syringomyelia, and the mechanisms which fill spinal subarachnoid cysts may be related to pressure waves directed both upwards and downwards. The merits and limitations of cough impulse as a clinical test for spinal blockage are discussed, and the suggestion is made that after further evaluation they may provide a more sensitive indication of spinal blockage than Queckenstedt's test.
10.1093/brain/99.2.331
Cough in adolescent with cystic fibrosis, from nightmare to COVID-19 stigma: A qualitative thematic analysis.
Journal of pediatric nursing
PURPOSE:Cough is part of the daily life of patients with Cystic fibrosis (CF) and its most common symptom. This study explored the experiences of adolescents with CF in Iran during the COVID-19 pandemic in relation to their cough. DESIGN AND METHODS:In this qualitative study, we conducted 32 semi-structured interviews with 21 adolescents with CF. We analyzed the data thematically. RESULTS:We identified three main themes among adolescents with CF in relation to coughing: 1. Cough is a permanent companion; 2. Coughing raises fear of double stigma; 3. Patients' individualized coping strategies to deal with coughing. Participants complained that cough interrupted daily tasks and sleep, drew unwanted attention in public places, and elicited questions about whether they were COVID-19 patients or substance users-both highly stigmatized identities. CONCLUSION:Although coughing is a protective mechanism for CF patients, frequent coughing often causes major challenges, particularly during the COVID pandemic, when people were acutely sensitive and aware about coughing. During the COVID-19 pandemic, in addition to taking care of themselves and managing the disease, CF patients therefore had to also overcome issues related to social stigma and isolation. PRACTICE IMPLICATIONS:Healthcare workers play an important role in increasing public awareness about CF and its symptoms, including cough. During the pandemic, healthcare workers can help reduce the stigma of coughing through public education. Healthcare workers can actively communicate with patients to identify severe and ineffective cases of cough due to exacerbation of the disease and refer them to a specialist.
10.1016/j.pedn.2022.02.013
Cough reflex induced by microinjection of citric acid into the larynx of guinea pigs: new coughing model.
Tanaka Motomu,Maruyama Kei
Journal of pharmacological sciences
We developed a new coughing model that evoked coughs by microinjection of citric acid into the larynx in unanesthetized unrestrained guinea pigs; additionally, we recorded synchronous sounds and waveforms of coughing utilizing built-in microphones and a whole body plethysmograph. The coughing model was able to distinguish a coughing response from other expiratory responses, such as an expiratory reflex or a sigh, by examining the waveform of the expiratory response and the existence of sound. It was not necessary to distinguish a cough from a sneeze, since the administration site was restricted to the larynx. Microinjection of 0.4 M citric acid, total of 20 microl (10 times, 2 microl at 30-s intervals), induced coughs (27.03 +/- 4.03 coughs in 10-min observation) that were stable and independent of the inhalation volume. In the inhalation studies, animals were exposed to citric acid only once, because the number of coughs remarkably decreased with repeated administration at intervals of 24 h (tachyphylaxis). However our coughing model was able to repeatedly challenge the microinjection of citric acid at an interval of 24 h. These results indicated that this coughing model was highly sensitive and correctly assessed the cough response.
Limosilactobacillus reuteri DSM-17938 for preventing cough in adults with mild allergic asthma: A double-blind randomized placebo-controlled cross-over study.
Satia Imran,Cusack Ruth,Stevens Catie,Schlatman Abbey,Wattie Jennifer,Mian Firoz,Killian Kieran J,O'Byrne Paul M,Bienenstock John,Forsythe Paul,Gauvreau Gail M
Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology
BACKGROUND:Cough is a common troublesome symptom in asthma which is neuronally mediated. Limosilactobacillus reuteri DSM-17938 (L. reuteri DSM-17938) is a probiotic shown to be effective in pre-clinical models at suppressing neuronal responses to capsaicin, a transient receptor potential vanilloid agonist (TRPV1). OBJECTIVE:Investigate the effects of DSM-17938 versus matched placebo on capsaicin-evoked coughs in mild allergic asthmatics. METHODS:We performed a 4-visit, randomized, double-blind, placebo-controlled, two-way cross-over study comparing full dose cough responses with inhaled capsaicin in mild allergic asthmatics after 1 month of treatment with DSM-17938 compared with matched placebo. Randomization and allocation to trial group were carried out by a central computer system. Histamine skin prick testing, airway hyper-responsiveness and inflammatory cells in induced sputum were measured at every visit. Blood was collected to extract PBMCs and stimulated with CD3/CD28 to ascertain the effects of DSM-17938 /placebo on T-cell cytokine responses. RESULTS:Seventeen subjects were recruited and 15 completed the study (8 females, mean age 27.3 years). There was no difference in the change in maximum capsaicin-evoked coughs (Emax) after treatment with L. reuteri DSM-17938 compared with placebo [mean difference 2.07 coughs (95% CI -2.77 to 6.91, p = .38) or relative changes in geometric mean ratios for the dose evoking at least half the Emax (ED50) [1.05 (95% CI 0.31-3.58, p = .94)], concentration evoking 2 coughs (C2) [0.63 (0.26-1.53), p = .28] and 5 coughs (C5) [0.79 (0.25-2.50), p = .67]. There was no effect on histamine skin prick wheal size, intensity of itch sensation, methacholine PC20, airway inflammation or T-cell responses after stimulation with CD3/CD28. There were no serious adverse events. One subject developed a mild upper respiratory tract infection and another mild transient nausea whilst on DSM-17938. CONCLUSION:In this small study in adults with mild allergic asthma, we found no evidence that L. reuteri DSM-17938 has any systemic effects on airway nerves, smooth muscle, sputum inflammatory cells, skin responses or T-cell responses after oral consumption. TRIAL REGISTRATION:Clinicaltrials.gov Identifier: NCT03603522.
10.1111/cea.13976
Coughing frequency in patients with persistent cough: assessment using a 24 hour ambulatory recorder.
Hsu J Y,Stone R A,Logan-Sinclair R B,Worsdell M,Busst C M,Chung K F
The European respiratory journal
Cough is an important symptom of many respiratory disorders. We determined the frequency and diurnal variation of cough in normal subjects and in patients with asthma or with persistent cough of unknown cause. We used a portable, solid-state, multiple-channel recorder to record cough sounds over a 24 h period. The audio-signal was recorded from a unidirectional microphone strapped over the chest wall, and electromyographic (EMG) signals from the lower respiratory muscles were simultaneously registered with surface electrodes. The recorded digital data were examined on an IBM-compatible computer, and the typical signals induced by cough (as assessed by voluntary or experimentally-induced cough) were counted. In 12 normal subjects, only 0-16 coughs were recorded over 24 h. In 21 stable asthmatics with a history of chronic cough ("asthma") the median number was 282 (ranges: 45-1,577), and in 14 patients with the predominant symptom of daily dry coughs ("chronic coughers") the median number was 794 (64-3,639). In both groups of patients, there was a diurnal variation of coughs, such that the least numbers occurred between 2 and 5 a.m. (< 3% of total). In the asthma group, there was no significant correlation between forced expiratory volume in one second (FEV1) (% predicted) or diurnal variation of peak expiratory flow and cough frequency. In the chronic coughers, there was a significant correlation between daytime cough numbers and daytime cough symptoms scores but not for the night-time values. Our data show that cough frequency is not determined by the severity of asthma in relatively stable asthmatics on inhaled steroids, and is reduced during sleep in both asthmatics and chronic cough patients. This portable cough recorder may be useful in the assessment of drug therapy for chronic cough.
Intravenous lidocaine suppresses fentanyl-induced coughing: a double-blind, prospective, randomized placebo-controlled study.
Pandey Chandra K,Raza Mehdi,Ranjan Rajeev,Lakra Archana,Agarwal Anil,Singh Uttam,Singh R B,Singh Prabhat K
Anesthesia and analgesia
IV lidocaine is effective in suppressing the cough reflex of tracheal intubation, extubation, bronchography, bronchoscopy, and laryngoscopy. We investigated this effect of lidocaine on fentanyl-induced cough in 502 patients of ASA physical status I and II scheduled for elective surgery. The patients were assigned to 2 equal groups to receive either lidocaine 1.5 mg/kg or placebo (0.9% saline) over 5 s 1 min before the administration of fentanyl 3 mug/kg in a randomized and double-blind fashion. Coughs were classified as coughing and graded as mild (1-2), moderate (3-4), or severe (5 or more). The results of the study suggest that IV lidocaine 1.5 mg/kg, when administered 1 min before fentanyl, is significantly effective in suppressing fentanyl-induced cough compared to placebo (0.9% saline) (218 versus 165 patients) (P < 0.002) but without affecting the severity of cough (P > 0.05).
10.1213/01.ANE.0000136967.82197.82
The effect of huffing and directed coughing on energy expenditure in young asymptomatic subjects.
Pontifex Edward,Williams Marie T,Lunn Rebecca,Parsons David
The Australian journal of physiotherapy
Coughing and huffing have been shown to be effective airway clearance techniques and some authors have anecdotally reported that a huff requires less energy than a series of coughs commencing and finishing at the same lung volume. The aim of this study was to determine whether there is a difference in the energy expenditure between periods of huffing and directed voluntary coughing commencing from the same initial lung volume in young asymptomatic subjects. Energy expenditure was measured using open-circuit indirect calorimetry equipment. Twenty-four non-smoking asymptomatic subjects (12 male, 12 female, aged 18-24 years), without any form of disease and within 10% of their predicted pulmonary function, completed the study. Energy expenditure was measured over three 10min, randomly ordered sessions of huffing, directed coughing and rest. The forced expiratory sessions comprised a single huff or double-barrel cough (both starting at total lung capacity) at the end of every two minutes. Each session was separated by a 5min washout period. No significant difference in energy expenditure was found between the huffing and directed coughing periods (mean difference 0.003 mL/kg/min (95% CI -0.160 to 0.114) and both produced significantly greater energy expenditure than rest (rest and huff mean difference 0.309 mL/kg/min (95% CI 0.080 to 0.549) and rest and cough mean difference 0.306 mL/kg/min (95% CI 0.074 to 0.508)). The suggested benefits of huffing versus coughing in terms of energy conservation are yet to be shown.
10.1016/s0004-9514(14)60225-7
Wearable RF Near-Field Cough Monitoring by Frequency-Time Deep Learning.
Hui Xiaonan,Zhou Jianlin,Sharma Pragya,Conroy Thomas B,Zhang Zijing,Kan Edwin C
IEEE transactions on biomedical circuits and systems
Coughing is a common symptom for many respiratory disorders, and can spread droplets of various sizes containing bacterial and viral pathogens. Mild coughs are usually overlooked in the early stage, not only because they are barely noticeable by the person and the people around, but also because the present recording method is not comfortable, private, or reliable for long-term monitoring. In this paper, a wearable radio-frequency (RF) sensor is presented to recognize the mild cough signal directly from the local trachea vibration characteristics, and can isolate interferences from nearby people. The sensor operates at the ultra-high-frequency band, and can couple the RF energy to the upper respiratory track by the near field of the sensing antenna. The retrieved tissue vibration caused by the cough airflow burst can then be analyzed by a convolutional neural network trained on the frequency-time spectra. The sensing antenna design is analyzed for performance improvement. During the human study of 5 participants over 100 minutes of prescribed routines, the overall recognition ratio is above 90% and the false positive ratio during other routines is below 2.09%.
10.1109/TBCAS.2021.3099865
Coughing and choking in motor neuron disease.
Hadjikoutis S,Eccles R,Wiles C M
Journal of neurology, neurosurgery, and psychiatry
OBJECTIVES:To assess the frequency and severity of coughing and choking episodes, possible related factors, and their association with chest infections in patients with motor neuron disease (MND). METHODS:Thirty seven patients with MND and 23 healthy volunteers were studied. Cough was assessed using a questionnaire and a 3 day diary, and volitional cough quantified by peak cough flow and sound intensity. Other clinical symptoms, smoking habit, affective state, oral secretions, bulbar signs, and quantitative assessments of swallowing and respiratory function were documented. RESULTS:Patients with MND coughed and choked significantly more often and to a greater degree than the healthy volunteers (26 of 37 patients with MND and 2 of 23 volunteers, p<0.001). Female sex, older age, abnormal speech, reduced swallowing capacity, and low forced vital capacity (FVC)% predicted were each significantly associated with excessive coughing and choking episodes in patients with MND. Smokers had significantly more severe and prolonged episodes of coughing and choking than non-smokers (p<0.05). Patients with upper motor neuron bulbar signs had a greater tendency to severe and prolonged episodes of coughing and choking than those without (p<0. 05). Chest infections were reported only rarely among the patients who coughed and choked. CONCLUSIONS:Coughing and choking episodes are common in patients with MND but infrequently associated with overt chest infection. Upper motor neuron bulbar signs may both promote factors (for instance, dysphagia) which trigger cough and reduce volitional capacity to suppress it.
10.1136/jnnp.68.5.601
Coughing, mucus accumulation, airway obstruction, and airway inflammation in control horses and horses affected with recurrent airway obstruction.
Robinson N Edward,Berney Cathy,Eberhart Sue,deFeijter-Rupp Heather L,Jefcoat Andrew M,Cornelisse Cornelis J,Gerber Vincent M,Derksen Frederik J
American journal of veterinary research
OBJECTIVE:To investigate relationships between cough frequency and mucus accumulation, airway obstruction, and airway inflammation and to determine effects of dexamethasone on coughing and mucus score. ANIMALS:13 horses with recurrent airway obstruction (RAO) and 6 control horses. PROCEDURE:6 RAO-affected and 6 control horses were stabled for 3 days. Coughing was counted for 4 hours before and on each day horses were stabled. Before and on day 3 of stabling, tracheal mucus accumulation was scored, airway obstruction was assessed via maximal change in pleural pressure (deltaPpl(max)), and airway inflammation was evaluated by use of cytologic examination of bronchoalveolar lavage fluid (BALF). Effects of dexamethasone (0.1 mg/kg, IV, q 24 h for 7 days) were determined in 12 RAO-affected horses. RESULTS:To assess frequency, coughing had to be counted for 1 hour. In RAO-affected horses, stabling was associated with increases in cough frequency, mucus score, and deltaPpl(max). Control horses coughed transiently when first stabled. In RAO-affected horses, coughing was correlated with deltaPpl(max), mucus score, and airway inflammation and was a sensitive and specific indicator of deltaPpl(max) > 6 cm H2O, mucus score > 1.0, and > 100 neutrophils/microL and > 20% neutrophils in BALF Dexamethasone reduced cough frequency, mucus score, and deltaPpl(max), but BALF neutrophil count remained increased. CONCLUSIONS AND CLINICAL RELEVANCE:Because of its sporadic nature, coughing cannot be assessed accurately by counting during brief periods. In RAO-affected horses, coughing is an indicator of airway inflammation and obstruction. Corticosteroid treatment reduces cough frequency concurrently with reductions in deltaPpl(max) and mucus accumulation in RAO-affected horses.
Increasing Efficiency in Evaluation of Chronic Cough: A Multidisciplinary, Collaborative Approach.
Patton Cynthia M,Lim Kaiser G,Ramlow Luke W,White Kathleen M
Quality management in health care
Chronic cough is the most common reason for medical office visits in the United States. The typical patient has coughed more than 8 years and seen many specialists. This quality improvement project is an ambulatory clinic redesign to deliver efficient, patient-centered care with interspecialty collaboration. Methodology included the Institute for Healthcare Improvement collaborative model focused on Lean/Six Sigma and ADKAR (Awareness, Desire, Knowledge, Ability, Reinforcement) Change Management. Interventions targeted education to referring providers, implementation of software changes, building a collaborative interdepartmental scheduling decision tree, and an interclinic dashboard enhancing communication and decision support. Outcome measures compare group resource utilization, evidenced by the total number of specialist referrals for same indication of chronic cough (International Classification of Diseases, Ninth Revision: 786.2), and length of time to complete evaluation. A retrospective review of 165 medical records yielded 2 groups, "current care" (n = 67) and "intervention" (n = 68). The number of specialist referrals per patient was reduced in the intervention group (M = 1.22, SD = 0.48) compared with the current care group (M = 3.33, SD = 1.02). Length of itinerary was reduced in the intervention group (M = 11.90, SD = 12.13, GM = 6.82) compared with the current care group (M = 126.93, SD = 158.13, GM = 54.8). Multidisciplinary collaboration, communication, coordinating diagnosis, and management of multifactorial conditions, such as chronic cough, are associated with lower costs and decreased utilization of health care resources.
10.1097/QMH.0000000000000072
The interaction between bronchoconstriction and cough in asthma.
Satia Imran,Badri Huda,Woodhead Mark,O'Byrne Paul M,Fowler Stephen J,Smith Jaclyn A
Thorax
Variable airflow obstruction is a pathophysiological hallmark of asthma; however, the interactions between acute bronchoconstriction and the cough reflex are poorly understood. We performed a randomised, single-blind, placebo-controlled, crossover study to investigate the interaction between bronchoconstriction and cough in asthma. Capsaicin was administered to evoke coughs and methacholine to induce bronchoconstriction. We demonstrated that acute bronchoconstriction increased capsaicin-evoked coughs, which improved as airway calibre spontaneously resolved. However, capsaicin-evoked coughing had no impact on methacholine-induced bronchoconstriction. This study provides evidence that bronchoconstriction increases the activation of capsaicin-responsive airway nerves, but the precise mechanisms and mediators involved require further evaluation. TRIAL REGISTRATION NUMBER:ISRCTN14900082.
10.1136/thoraxjnl-2016-209625
High peak inspiratory pressure may be associated with intraoperative coughing during neurosurgery under general anesthesia without neuromuscular blockade: a retrospective study.
BMC anesthesiology
BACKGROUND:The endotracheal cuff pressure depends on the airway pressure during positive-pressure ventilation. A high endotracheal cuff pressure may be related to intraoperative coughing, which can be detrimental during neurosurgery. We investigated the incidence of intraoperative coughing and its association with peak inspiratory pressure (PIP) during neurosurgery under general anesthesia without neuromuscular blockade. METHODS:This retrospective study divided 1656 neurosurgical patients who underwent total intravenous anesthesia without additional neuromuscular blockade after tracheal intubation into high (PIP > 21.6 cmHO, n = 318) and low (PIP ≤ 21.6 cmHO, n = 1338) PIP groups. After propensity score matching, 206 patients were selected in each group. Demographic, preoperative, surgical, and anesthetic data were collected retrospectively from electronic medical records and continuous ventilator, infusion pump, and bispectral index data from a data registry. RESULTS:Intraoperative coughing occurred in 30 (1.8%) patients, including 9 (0.5%) during the main surgical procedure. Intraoperative coughing was more frequent in the high PIP group than in the low PIP group before (14/318 [4.4%] vs. 16/1338 [1.2%], P < 0.001) and after (13/206 [6.3%] vs. 1/206 [0.5%], P = 0.003) propensity score matching. In multivariable logistic regression analysis after propensity score matching, a high PIP (odds ratio [95% confidence interval] 14.22 [1.81-111.73], P = 0.012), tidal volume divided by predicted body weight (mL/kg, 1.36 [1.09-1.69], P = 0.006), and surgical duration (min, 1.01 [1.00-1.01], P = 0.025) predicted intraoperative coughing. CONCLUSION:The incidence of intraoperative coughing was 1.8% in neurosurgical patients undergoing general anesthesia without neuromuscular blockade and might be associated with a high PIP.
10.1186/s12871-023-02080-6
[Effect of optimizing anesthetic injecting sequence during induction on fentanyl-induced coughing].
Wang Lei,Yao Jin-hua,Zhu Jun-jian,Liu Bin,Zhu Jian-guo,Zhou Da-chun
Zhonghua yi xue za zhi
OBJECTIVE:To observe the effect of optimizing anesthetic injecting sequence during induction on fentanyl-induced coughing. METHODS:One hundred and twenty ASA I or II elective patients undergoing general anesthesia were randomly allocated to optimized group or control group: the optimized group induced with midazolam 0.06 mg/kg, followed by fentanyl 1 mg/kg at 1 min later, vecuronium 0.1 mg/kg at 1 min 55 s, propofol 1.5-2 mg/kg at 2 min, a second dose of 3 mg/kg fentanyl at 2 min 20 s, intubated at time 5 min; the control group was induced with the same medication but all the fentanyl (4 mg/kg) was injected at time 1 min. Coughing after fentanyl injection was observed and hemodynamic parameters were recorded. RESULTS:Hemodynamic changes were identical between the two groups indicated similar intubation response suppression. The incidence of fentanyl-induced coughing was significantly lower in the optimized group (4/60) than in the control group (23/60) (P < 0.01). CONCLUSION:Optimizing anesthetic injecting sequence during induction by separate fentanyl into two boluses significantly reduce fentanyl-induced coughing without affecting intubation response suppression.
Chronic cough: an update.
Iyer Vivek N,Lim Kaiser G
Mayo Clinic proceedings
Cough persisting beyond 8 weeks (ie, chronic cough) is one of the most common reasons for an outpatient visit. A protracted cough can negatively affect one's quality of life by causing anxiety, physical discomfort, social isolation, and personal embarrassment. Herein, the anatomy and physiology of the cough reflex are reviewed. Upper airway cough syndrome, asthma, eosinophilic bronchitis, and gastroesophageal reflux disease account for most chronic cough after excluding smoking, angiotensin-converting enzyme inhibitor use, and chronic bronchitis. Many patients have more than one reason for chronic cough. Treating the underlying cause(s) resolves cough in most instances. There are some coughs that seem refractory despite an extensive work-up. The possibility of a hypersensitive cough reflex response has been proposed to explain these cases. Several clinical algorithms to evaluate chronic cough are presented.
10.1016/j.mayocp.2013.08.007
Pelvic floor muscle reflex activity during coughing - an exploratory and reliability study.
Luginbuehl Helena,Baeyens Jean-Pierre,Kuhn Annette,Christen Regula,Oberli Bettina,Eichelberger Patric,Radlinger Lorenz
Annals of physical and rehabilitation medicine
OBJECTIVES:Activities that provoke stress urinary incontinence (SUI) rapidly increase the intra-abdominal pressure and the impact loading on the pelvic floor muscles (PFMs). Coughing can cause urinary leakage and is often used to test SUI. However, PFM characteristics during coughing, including their reliability, have not been investigated. Here, we used electromyography (EMG) to describe PFM pre-activity and reflexivity during coughing and examined the reliability of the measurements. METHODS:This was an exploratory and reliability study including 11 young healthy women to characterize EMG reflex activity in PFMs during coughing. We describe 6 variables, averaged over 3 coughs per subject, and tested their reliability (intraclass correlation coefficient 3,1 [ICC(3,1)] and ICC(3,k), related standard error of measurement (SEM) and minimal difference [MD]). The variables represented the mean EMG activity for PFMs during 30-ms time intervals of pre-activity (initial time point of coughing [T0] and minus 30ms) and reflex activity (T0-30, 30-60, 60-90, 90-120 and 120-150ms after T0) of stretch-reflex latency responses. RESULTS:The mean %EMG (normalized to maximal voluntary PFM contraction) for EMG variables was 35.1 to 52.2 and was significantly higher during coughing than for PFM activity at rest (mean 24.9±3.7%EMG; P<0.05). ICC(3,k) ranged from 0.67 to 0.91 (SEM 6.1-13.3%EMG and MD 16.7-36.8%EMG) and was higher than ICC(3,1) (range 0.40-0.77; SEM 9.0-18.0%EMG, MD 24.9-50.0%EMG). CONCLUSIONS:PFM activity during reflex latency response time intervals during coughing was significantly higher than at rest, which suggests PFM pre-activity and reflex activity during coughing. Although we standardized coughing, EMG variables for PFM activity showed poor reliability [good to excellent ICC(3,k) and fair to excellent ICC(3,1) but high SEM and MD]. Therefore, coughing is expected to be heterogeneous, with low reliability, in clinical test situations. Potential crosstalk from other muscles involved in coughing could limit the interpretation of our results.
10.1016/j.rehab.2016.04.005
Cough dynamics in adults receiving tuberculosis treatment.
PloS one
Cough is a characteristic symptom of tuberculosis, is the main cause of transmission, and is used to assess treatment response. We aimed to identify the best measure of cough severity and characterize changes during initial tuberculosis therapy. We conducted a prospective cohort of recently diagnosed ambulatory adult patients with pulmonary tuberculosis in two tertiary hospitals in Lima, Peru. Pre-treatment and five times during the first two months of treatment, a vibrometer was used to capture 4-hour recordings of involuntary cough. A total of 358 recordings from 69 participants were analyzed using a computer algorithm. Total time spent coughing (seconds per hour) was a better predictor of microbiologic indicators of disease severity and treatment response than the frequency of cough episodes or cough power. Patients with prior tuberculosis tended to cough more than patients without prior tuberculosis, and patients with tuberculosis and diabetes coughed more than patients without diabetes co-morbidity. Cough characteristics were similar regardless of HIV co-infection and for drug-susceptible versus drug-resistant tuberculosis. Tuberculosis treatment response may be meaningfully assessed by objectively monitoring the time spent coughing. This measure demonstrated that cough was increased in patients with TB recurrence or co-morbid diabetes, but not because of drug resistance or HIV co-infection.
10.1371/journal.pone.0231167
Eight International London Cough Symposium 2014: Cough hypersensitivity syndrome as the basis for chronic cough.
Chung Kian Fan,Canning Brendan,McGarvey Lorcan
Pulmonary pharmacology & therapeutics
At the Eighth International London Cough Conference held in London in July 2014, the focus was on the relatively novel concept of cough hypersensitivity syndrome (CHS) as forming the basis of chronic cough. This concept has been formulated following understanding of the neuronal pathways for cough and a realisation that not all chronic cough is usually associated with a cause. The CHS is defined by troublesome coughing triggered by low level of thermal, mechanical or chemical exposure. It also encompasses other symptoms or sensations such as laryngeal hypersensitivity, nasal hypersensitivity and possibly also symptoms related to gastrooesopahgeal reflux. The pathophysiologic basis of the CHS is now being increasingly linked to an enhancement of the afferent pathways of the cough reflex both at the peripheral and central levels. Mechanisms involved include the interactions of inflammatory mechanisms with cough sensors in the upper airways and with neuronal pathways of cough, associated with a central component. Tools for assessing CHS in the clinic need to be developed. New drugs may be developed to control CHS. A roadmap is suggested from the inception of the CHS concept towards the development of newer antitussives at the Symposium.
10.1016/j.pupt.2015.08.009
The cough reflex in animals: relevance to human cough research.
Canning Brendan J
Lung
All mammalian species studied cough or display some similar respiratory reflex upon aerosol challenge with tussigenic stimuli such as citric acid or capsaicin. Animals cough to the same stimuli that evoke coughing in humans, and therapeutic agents that display antitussive effects in human studies also prevent coughing in animals. The many invasive procedures and complementary in vitro studies possible in animals but not readily reproduced in human subjects, along with the proven predictive value of cough studies in animals, provide the rationale for animal modeling of human cough. The advantages and disadvantages of studying cough in animals are discussed.
10.1007/s00408-007-9054-6
Urge-to-cough: what can it teach us about cough?
Davenport Paul W
Lung
The Urge-to-Cough is a component of the brain motivation system that mediates cognitive responses to cough stimuli. There are six stages to the cough motivation-to-action system: (1) stimulus, the trigger for the neural event; (2) urge, the physical need to respond to the stimulus; (3) desire, translation of urge into a central neural targeted goal; (4) action, physical response that satisfies the urge-desire; (5) evidence, feedback to the neural system on the action; (6) reward, sensory system that determines if the urge was satisfied. Urge-to-Cough is related to three fundamental types of cough: (1) reflex cough, (2) voluntary cough, and (3) behavioral cough. Urge-to-Cough with reflex cough can be studied by measuring the sensations elicited by a cough stimulus. Neural processes with voluntary cough can be studied using magnitude production cognitive psychometric methods. Results of these studies have shown if the subjects can reliably estimate their Urge-to-Cough, the urge increases with increasing cough stimulus, there is a correlation between the Urge-to-Cough and cough intensity, there is a threshold for eliciting the sensation of the urge that precedes the motor cough behavior, subjects can voluntarily produce coughs of varying magnitudes, the motor cough pattern is directly related to the perceived magnitude of a cough, volitional triggers of a cough are directly related to the reflex cough pattern, and neural triggers of cough initiate a stereotypic motor output. Understanding the Urge-to-Cough motivation-to-action system opens new strategies for research on central neural cough mechanisms.
10.1007/s00408-007-9045-7
Performance evaluation of human cough annotators: optimal metrics and sex differences.
BMJ open respiratory research
INTRODUCTION:Despite its high prevalence and significance, there is still no widely available method to quantify cough. In order to demonstrate agreement with the current gold standard of human annotation, emerging automated techniques require a robust, reproducible approach to annotation. We describe the extent to which a human annotator of cough sounds (a) agrees with herself (intralabeller or intrarater agreement) and (b) agrees with other independent labellers (interlabeller or inter-rater agreement); we go on to describe significant sex differences in cough sound length and epochs size. MATERIALS AND METHODS:24 participants wore an audiorecording smartwatch to capture 6-24 hours of continuous audio. A randomly selected sample of the whole audio was labelled twice by an expert annotator and a third time by six trained annotators. We collected 400 hours of audio and analysed 40 hours. The cough counts as well as cough seconds (any 1 s of time containing at least one cough) from different annotators were compared and summary statistics from linear and Bland-Altman analyses were used to quantify intraobserver and interobserver agreement. RESULTS:There was excellent intralabeller (less than two disagreements per hour monitored, Pearson's correlation 0.98) and interlabeller agreement (Pearson's correlation 0.96), using cough seconds as the unit of analysis decreased annotator discrepancies by 50% in comparison to coughs. Within this data set, it was observed that the length of cough sounds and epoch size (number of coughs per bout or attach) differed between women and men. CONCLUSION:Given the decreased interobserver variability in annotation when using cough seconds (vs just coughs) we propose their use for manually annotating cough when assessing of the performance of automatic cough monitoring systems. The differences in cough sound length and epochs size may have important implications for equality in the development of cough monitoring tools. TRIAL REGISTRATION NUMBER:NCT05042063.
10.1136/bmjresp-2023-001942
Cough reduction using capsaicin.
Ternesten-Hasséus Ewa,Johansson Ewa-Lena,Millqvist Eva
Respiratory medicine
UNLABELLED:Chronic unexplained cough triggered by environmental irritants is characterized by increased cough reflex sensitivity, which can be demonstrated by means of inhaled capsaicin. Topical capsaicin can be used to improve non-allergic rhinitis and intestinal hypersensitivity and to reduce neuropathic pain. OBJECTIVES:We established whether an oral intake of natural capsaicin (chilli) could desensitize the cough reflex and improve unexplained coughing. METHODS:Twenty-four patients with irritant-induced, unexplained chronic cough and 15 controls were included in the study. For 4 weeks, the participants took capsules with pure capsaicin, and for 4 weeks, they took placebo capsules. The protocol was crossover, randomized, and double blind. Cough sensitivity during the study was evaluated by a standardized capsaicin inhalation cough test that assessed the capsaicin concentration required to reach two coughs (C2) and five coughs (C5). Participants were also administered questionnaires on cough and cough-related symptoms. RESULTS:Three patients withdrew before the study end, one during the active treatment period and two during the placebo period. After treatment with capsaicin, the thresholds for C2 were higher (improved) both in patients (p < 0.020) and in controls (p < 0.0061) compared to after the placebo period. Among patients, the concentration needed to reach C2 (p < 0.0004) and C5 (p < 0.0009) increased after the period with the active substance compared to cough thresholds at baseline. The cough symptom scores improved after 4 weeks of active treatment (p < 0.0030) compared to the baseline scores. CONCLUSION:Capsaicin powder taken orally decreased capsaicin cough sensitivity and cough symptoms. The findings suggest a desensitization of the cough-sensitive transient receptor potential vanilloid-1 (TRPV1).
10.1016/j.rmed.2014.11.001
Quality of life in patients with chronic cough.
Young Emma C,Smith Jaclyn A
Therapeutic advances in respiratory disease
Chronic cough is a relatively common symptom for which effective, acceptable treatments are lacking. Many patients suffer frequent coughing over several years without resolution and this has significant physical, social and psychological consequences. The recent development of cough-specific quality-of-life tools now allows quantification of the burden of coughing both in patients specifically presenting with chronic cough and also in common respiratory conditions.
10.1177/1753465809358249
Physiological and pathophysiological down-regulation of cough.
Widdicombe John,Singh Vijay
Respiratory physiology & neurobiology
Recent clinical studies have emphasized the up-regulation (sensitization) of cough in pathological conditions of the airways. However there are also many situations where voluntary and reflex cough can be down-regulated. These include: (1) chemical stimulation of breathing by hypercapnia or hypoxia or both, establishing that cough sensitivity can be inversely related to drive to breathing; (2) voluntary inhibition of cough, probably similar in mechanism to the depression of cough that can be induced by hypnosis and other branches of alternative medicine; (3) the placebo effect of many antitussive treatments; (4) sleep; (5) general anaesthesia; (6) central nervous disorders such as coma, stroke, Parkinson's disease and several other conditions where the defect in the protective reflexes may lead to aspiration pneumonia; (7) increased activity in various afferent inputs from viscera in the thorax and abdomen; (8) a number of bronchopulmonary clinical disorders. The list is long, but regrettably the nervous mechanisms of these down-regulations have been little studied. In addition there are a number of situations, such as exercise, coitus, talking and singing which, while important to coughing humans, have been not investigated in relation to cough. Most of the studies have been with experimental animals, and their extension to human research is desirable. In view of the importance of cough and other defensive reflexes in maintaining human well-being, far more research is needed. The field is wide-open.
10.1016/j.resp.2005.04.013
Healthcare utilization and costs in chronic cough.
Current medical research and opinion
BACKGROUND:Chronic cough is a common reason for medical consultations and is associated with considerable physical and psychological morbidity. This study investigated healthcare use and cost in chronic cough and assessed its relationship with cough severity, health status, objective cough frequency (CF), and anxiety and depression. METHODS:This was a prospective study of consecutive patients with chronic cough from a specialist clinic who completed a cough severity visual analogue scale (VAS), cough-specific health status (Leicester Cough Questionnaire; LCQ) and general health status EuroQol EQ-5D-5L, Generalized Anxiety Disorder (GAD7), Patient Health Questionnaire (PHQ9), and 24-hour objective CF monitoring with Leicester Cough Monitor (LCM). Case notes were reviewed for coughspecific healthcare use 12 months before and after the first cough clinic consultation. Resource use included general practitioner and hospital clinic visits, investigations, and treatments. Unit costs for healthcare use were derived predominantly from National Health Service Reference Costs. RESULTS:One hundred participants with chronic cough were recruited (69% female, median duration 3 years, mean age 58 years). The diagnoses of cough were unexplained (57%), refractory (27%), and other (16%). Cough severity, health status, and CF were: median (IQR) VAS 59.5 (30-79) mm, mean (SD) LCQ 11.9 (4.0), mean (SD) EQ-5D-5L 0.846 (0.178), and geometric mean (SD) CF 15.3 (2.5) coughs/hr, respectively. The mean (SD) total cost per individual for coughrelated healthcare utilization was £1,663 (747). Diagnostic investigations were the largest contributor to cost (63%), followed by cough clinic consultations (25%). In multivariate analysis, anxiety (GAD7) and coughrelated health status (LCQ) were associated with increased cost (.001 and .037). CONCLUSION:Healthcare cost associated with chronic cough are largely due to diagnostic investigations and clinic consultations. The predictors of costs were health status (LCQ) and anxiety. Further studies should investigate the optimal management protocols for patients with chronic cough.
10.1080/03007995.2022.2065142
Cough-Inducing Method Using a Tartaric Acid Nebulizer for Patients with Silent Aspiration.
Dysphagia
The tartaric acid nebulizer is a well-known cough test to evaluate cough function. This study aimed to evaluate the effectiveness of a cough-inducing method using tartaric acid (CiTA). Patients with dysphagia examined by videofluoroscopic examination of swallowing (VF) at a single institution from May 2017 to August 2017 were included in this retrospective observational study. Although undergoing VF, patients who had aspirated without reflexively coughing or who had coughed insufficiently, were instructed to cough voluntarily. Patients who could not cough voluntarily or had expectorated insufficiently underwent the CiTA method. The rate of cough induction and the effectiveness of expectoration using the CiTA method were evaluated. One hundred fifty-four patients (mean age 69.2 ± 16.8 years) were evaluated. Eighty-seven patients aspirated during VF. Of those patients, 15 were able to expectorate via the cough reflex, 18 were able to expectorate with a voluntary cough, and 12 required suctioning for removal of aspirated material. The remaining 42 patients underwent the CiTA method. Thirty-eight patients (90.4%) could reflexively cough, and 30 (71.4%) could expectorate the aspirated material. This novel method, CiTA, was effective for cough induction in patients with dysphagia, especially for those with silent aspiration.
10.1007/s00455-021-10313-4
Audio-based cough counting using independent subspace analysis.
Leamy Paul,Burke Ted,Barry Dan,Dorran David
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
In this paper, an algorithm designed to detect characteristic cough events in audio recordings is presented, significantly reducing the time required for manual counting. Using time-frequency representations and independent subspace analysis (ISA), sound events that exhibit characteristics of coughs are automatically detected, producing a summary of the events detected without the need for a pre-trained model. Using a dataset created from publicly available audio recordings, this algorithm has been tested on a variety of synthesized audio scenarios representative of those likely to be encountered by subjects undergoing an ambulatory cough recording, achieving a true positive rate of 76% with an average of 2.85 false positives per minute.
10.1109/EMBC46164.2021.9630970
Numerical Analysis of Airway Mucus Clearance Effectiveness Using Assisted Coughing Techniques.
Ren Shuai,Li Wei,Wang Lin,Shi Yan,Cai Maolin,Hao Liming,Luo Zihao,Niu Jinglong,Xu Weiqing,Luo Zujin
Scientific reports
Cough is a protective respiratory reflex used to clear respiratory airway mucus. For patients with cough weakness, such as chronic obstructive pulmonary disease, neuromuscular weakness disease and other respiratory diseases, assisted coughing techniques are essential to help them clear mucus. In this study, the Eulerian wall film model was applied to simulate the coughing clearance process through a computational fluid dynamics methodology. Airway generation 0 to generation 2 based on realistic geometry is considered in this study. To quantify cough effectiveness, cough efficiency was calculated. Moreover, simulations of four different coughing techniques applied for chronic obstructive pulmonary disease and neuromuscular weakness disease were conducted. The influences of mucus film thickness and mucus viscosity on cough efficiency were analyzed. From the simulation results, we found that with increasing mucus film thickness and decreasing mucus viscosity, cough efficiency improved accordingly. Assisted coughing technologies have little influence on the mucus clearance of chronic obstructive pulmonary disease models. Finally, it was observed that the cough efficiency of the mechanical insufflation-exsufflation technique (MIE) is more than 40 times the value of an unassisted coughing technique, which indicates that the MIE technology has a great effect on airway mucus clearance for neuromuscular weakness disease models.
10.1038/s41598-020-58922-7
Are there clinical features of a sensitized cough reflex?
McGarvey L,McKeagney P,Polley L,MacMahon J,Costello R W
Pulmonary pharmacology & therapeutics
Cough reflex hypersensitization is a key feature in patients with troublesome cough. The clinical consequence of this hypersensitive state is typified by bouts of coughing often triggered by low threshold stimuli encountered by the patient during normal daily activities including exposure to aerosols, scents and odours, a change in air temperature and when talking or laughing. These features are often perceived by cough patients to be the most disruptive aspect of their condition and undoubtedly contribute to impaired quality of life. Patients with troublesome cough may describe a range of additional symptoms and sensations including an 'urge to cough' or the feeling of an 'itch' at the back of the throat, or a choking sensation and occasionally chest pain or breathlessness. It is uncertain if these features arise due to the processes responsible for cough reflex sensitization or as a direct consequence of the underlying cough aetiology. In an attempt to understand the clinical features of a sensitized cough reflex, the spectrum of symptoms typically described by cough patients will be reviewed and possible underlying mechanisms considered. Since an intact cough reflex is crucial to airway protection, anti-tussive treatment that attenuates the hypersensitive cough state rather than abolishing the cough reflex completely would be preferable. Identifying such agents remains a clinical, scientific and pharmacological challenge.
10.1016/j.pupt.2008.11.003
Laryngeal Dysfunction Manifesting as Chronic Refractory Cough and Dyspnea: Laryngeal Physiology in Respiratory Health and Disease.
Chest
TOPIC IMPORTANCE:Laryngeal dysfunction as a cause of chronic refractory cough and episodic dyspnea is often missed, which results in unnecessary testing and delays in diagnosis. Understanding laryngeal roles in breathing and airway protection can help to appreciate the propensity to laryngeal dysfunction with aging, chronic lung disease, and sleep apnea. REVIEW FINDINGS:The human larynx is a complex muscular structure that is responsible for multiple roles of breathing, vocalization, coughing, and swallowing. To undertake these activities, the larynx has a high density of sensory and motor innervation. In addition to common embryological origins with the pharynx and esophagus, with which many laryngeal activities are shared, somatomotor and autonomic pathways regulate emotional, cognitive, and complex motor sequence-planning activities within the larynx. Due to its unique location, the larynx is susceptible to infectious and gastroesophageal reflux-related insults. Couple this with key roles in regulation of airflow and mediation of airway protective reflexes, it is not surprising that neuropathic abnormalities and muscle dysfunction frequently develop. The expression of laryngeal dysfunction as hypersensitivity to mechanical, thermal, chemical, and other stimuli leads to exaggerated airway protective reflexes (laryngeal adductor reflex and cough reflex) manifesting as dyspnea and cough. SUMMARY:Pulmonologists should incorporate assessment of laryngeal dysfunction during evaluation of chronic refractory cough and dyspnea. Recognition of laryngeal hypersensitivity in the patient with chronic refractory cough can identify patients who may benefit from cough suppression therapies. Similarly, timely identification of inducible laryngeal obstruction may not only resolve episodic dyspnea but lessen the need for unnecessary testing and treatments.
10.1016/j.chest.2024.03.026
Coughing and diaphragmatic breathing exercise: What is the repercussion on respiratory mechanics of children and adolescents with cystic fibrosis?
Castilho Tayná,Gonçalves Wamosy Renata Maba,Cardoso Juliana,Camila Mucha Francieli,Jandt Uriel,Schivinski Camila Isabel Santos
International journal of clinical practice
INTRODUCTION:The aim of this study was to investigate the immediate effect of coughing episodes and diaphragmatic breathing exercise (DBE) on respiratory mechanics of children/adolescents with cystic fibrosis (CF). METHODS:It is a cross-sectional analytical study that occurred in a reference center for children with CF. Forty-five children/adolescents with CF (60% male; mean age 10.22 ± 2.84 years old; mean forced expiratory volume in 1 second 73.74 ± 21.38% predicted) were divided into 3 groups according to the R5 parameter response to the DBE: G1 (increased R5), G2 (no change R5), and G3 (decreased R5). The children/adolescents performed 5 successive coughs and 10 DBE. The main outcome measures were the impulse oscillometry system (IOS) parameters evaluated before, during, and after the interventions. RESULTS:In the total sample, the IOS parameters (Z5, R5, and R20) were worse after coughing, and they did not change after the DBE. In the G1, the parameters were progressively worsening during the interventions. In the G2, they worsened after coughing and after the DBE. In the G3, they worsened after coughing; however, after the DBE, the IOS parameters have improved and returned close to the baseline. CONCLUSIONS:The children/adolescents with CF airway resistance got worse after coughing episodes, and 10 DBE repetitions did not affect the respiratory mechanics in most of the sample. Meanwhile, in the group with older children, the DBE worsened the respiratory mechanics, yet in the younger group it improved.
10.1111/ijcp.14879
Cough sensors. V. Pharmacological modulation of cough sensors.
Mazzone S B,Undem B J
Handbook of experimental pharmacology
Several airway afferent nerve subtypes have been implicated in coughing. These include bronchopulmonary C-fibers, rapidly adapting airway mechanoreceptors and touch-sensitive tracheal Adelta-fibers (also called cough receptors). Although the last two afferent nerve subtypes are primarily sensitive to mechanical stimuli, all can be acted upon by one or more different chemical stimuli. In this review we catalogue the chemical agents that stimulate and/or modulate the activity of the airway afferent nerves involved in cough, and describe the specific mechanisms involved in these effects. In addition, we describe the mechanisms of action of a number of chemical inhibitors of these afferent nerve subtypes, and attempt to relate this information to the regulation of coughing in health and disease.
10.1007/978-3-540-79842-2_6
Neural dysfunction following respiratory viral infection as a cause of chronic cough hypersensitivity.
Undem Bradley J,Zaccone Eric,McGarvey Lorcan,Mazzone Stuart B
Pulmonary pharmacology & therapeutics
Respiratory viral infections are a common cause of acute coughing, an irritating symptom for the patient and an important mechanism of transmission for the virus. Although poorly described, the inflammatory consequences of infection likely induce coughing by chemical (inflammatory mediator) or mechanical (mucous) activation of the cough-evoking sensory nerves that innervate the airway wall. For some individuals, acute cough can evolve into a chronic condition, in which cough and aberrant airway sensations long outlast the initial viral infection. This suggests that some viruses have the capacity to induce persistent plasticity in the neural pathways mediating cough. In this brief review we present the clinical evidence of acute and chronic neural dysfunction following viral respiratory tract infections and explore possible mechanisms by which the nervous system may undergo activation, sensitization and plasticity.
10.1016/j.pupt.2015.06.006
Translational review: Neuroimmune mechanisms in cough and emerging therapeutic targets.
McGovern Alice E,Short Kirsty R,Kywe Moe Aung Aung,Mazzone Stuart B
The Journal of allergy and clinical immunology
Cough is an essential defensive behavior for maintaining airway patency and to protect the lungs from potentially harmful agents. However, inflammatory pathologies can sensitize and activate the neural pathways regulating cough, leading to excessive and nonproductive coughing that serves little protective utility. Problematic cough continues to be one of the most common reasons for seeking medical advice, yet for many patients, it can be refractory to disease-specific treatments and currently available antitussive therapies. The effect of inflammation on cough neural processing occurs not only at the level of the bronchopulmonary sensory nerve terminals but also within the nervous system at multiple peripheral and central sites. Sensory nerves also actively regulate inflammation, and it is therefore a complex interplay between the immune and nervous systems that contributes to chronic cough and the associated sensory hypersensitivities. In this review we provide a brief overview of cough neurobiology in health and disease and then explore the peripheral and central nervous system sites at which neuroimmune interactions can occur. We present advancements in the development of effective antitussive therapies and suggest novel targets for future consideration.
10.1016/j.jaci.2018.09.004
Monitoring chronic cough: current and future techniques.
Smith Jaclyn
Expert review of respiratory medicine
Coughing produces a characteristic sound that is readily recognized by the human ear and provides the opportunity to objectively quantify coughing through acoustic recordings. The development of digital recording technologies has facilitated such recordings over the extended time periods needed to capture symptom episodes. However, the manual counting of coughs by listening to long recordings is time-consuming, laborious and restricts usage to research studies. This article outlines the challenges in recording, analyzing and quantifying cough sounds and describes the systems under development. Progress is being made towards automated algorithms to identify and count cough sounds; however, current systems have only been tested over short time periods and in limited patient groups. Further work is required to achieve broadly applicable accurate cough monitoring systems.
10.1586/ers.10.63
The epidemiology of cough.
Kauffmann Francine,Varraso Raphaëlle
Pulmonary pharmacology & therapeutics
Cough is a common symptom that affects a large proportion of the general population, but has been somewhat neglected in the epidemiological literature in the recent years. Various types of coughs are described based on life-long epidemiological surveys. Using published and unpublished data from three epidemiological studies (the European Community Respiratory Health survey, the French Epidemiological study on the Genetics and environment of asthma (EGEA) and the French E3N study), some specific aspects are discussed in detail. Phenotypic heterogeneity according to chronicity, or its productive nature, or its daytime or nocturnal characteristics are discussed. The association of cough with asthma and gender is described, together with its evolution over a 12-year period. The potential for genetic studies of cough is discussed.
10.1016/j.pupt.2010.10.012
Breaking the sound barrier? Pitfalls and benefits of acoustic cough monitoring.
Houghton Lesley A,Smith Jaclyn A
The American journal of gastroenterology
Traditionally push-button and symptom diaries have been used to document cough events, especially when examining temporal associations between cough and reflux events. More recently, acoustic devices have allowed more accurate recording of cough events, and compared with the latter traditional techniques reported 6-18 times more coughing. Whether the differences reported between these techniques represents disparities in subject groups or cough detection and quantification methods is unknown. In this issue of the American Journal of Gastroenterology, Kavitt et al. show that listeners of such recordings have a 4-fold increase in odds of recording cough events compared with patients using push-button techniques, and that even when using a 5-min window to assess temporal concordance/discordance, over 70% of coughs were not reported by the patients. These observations have potential significant implications when assessing temporal associations between cough and reflux, and thus any clinical decision making based on these data. This editorial examines both the findings of Kavitt et al. and discusses the pitfalls and benefits of validated accurate documentation of cough.
10.1038/ajg.2012.345
Central nervous system control of cough: pharmacological implications.
Mazzone Stuart B,McGovern Alice E,Cole Leonie J,Farrell Michael J
Current opinion in pharmacology
For many years the idea of a cough center in the brain dominated discussions in the field without any substantial progress in defining what this cough center is or how it functions. Substantial progress has now been made and many of the central neural elements involved in coughing are being described. Furthermore, hypothesis driven research into the function of these neural elements is providing exciting new leads for possible therapeutic targets. The concept of a specific, centrally acting drug for cough suppression is fast becoming a reality. This review summarizes the key findings from the past few years and provides a perspective on future directions for the development of novel antitussives.
10.1016/j.coph.2011.05.005
Objective measurement of acoustic intensity of coughing for clearance of penetration and aspiration on video-fluoroscopy.
Wallace Emma,Macrae Phoebe,Huckabee Maggie-Lee
International journal of speech-language pathology
PURPOSE:This preliminary, exploratory study evaluated the acoustic intensity of effective and ineffective clearance of penetrated and aspirated material from the laryngeal vestibule in patients with dysphagia. METHOD:A lapel microphone was attached anterior to participants' tragus and recorded coughing in decibels during their videofluoroscopic swallowing studies (VFSS). RESULT:Eighty-eight patients were recruited. Thirteen patients, with visible airway invasion and coughing were included in the final analysis. No coughs were effective at expelling aspirated material from the airway ( = 10). Both effective (4/7) and ineffective (3/7) coughing to penetration were recorded. The mean acoustic intensity of effective coughing to penetration was -44.0 dBFS (decibel level relative to full scale) [SD = 7.3, 95% CI = -51.14, -36.86], and ineffective coughing to penetration was only marginally lower at -42.9 dBFS [SD = 2.0, 95% CI = -45.21, -40.59]. CONCLUSION:No coughs were effective at expelling aspirated material from the airway. Some coughs effectively expelled penetrated material from the airway. However, the relationship between acoustic intensity and cough effectiveness is unclear due to the limited number of observations. Given that perceptual evaluation of coughing is widely used in dysphagia clinical practice to determine cough effectiveness, this is an important area for future research.
10.1080/17549507.2020.1784280
Differential diagnosis of chronic cough.
Weldon David R
Allergy and asthma proceedings
Coughing that lasts >3 weeks is generally considered chronic. The causes of chronic cough are many. Most often, chronic cough is due to postnasal drainage, asthma, and/or gastroesophageal disease. However, other causes such as laryngopharyngeal reflux, vocal cord dysfunction, occult sinusitis, pertussis, and angiotensin-converting enzyme inhibitor should be considered. Even rarer entities will be discussed as well as some of the pathophysiology associated with the cough reflex.
Efficacy of coughing in tetraplegic patients.
van Der Schans C P,Piers D A,Mulder G A
Spine
STUDY DESIGN:A randomized cross-over design study in six tetraplegic patients. OBJECTIVES:To investigate the efficacy of coughing in tetraplegic patients. SUMMARY OF BACKGROUND DATA:In tetraplegic patients, pulmonary complications due to insufficient clearance of bronchial mucus frequently are described. Coughing in tetraplegic patients is thought to be insufficient because of severely impaired expiratory muscle function. More recently, however, it has been reported that many tetraplegic patients may have dynamic airway compression and thus a more or less effective cough. METHODS:Mucus clearance was measured using a radioactive aerosol tracer technique during 45 minutes on 2 days: once without intervention, and once with voluntary coughing in the period 15 to 30 minutes (once every 30 seconds). Measurements were done in a randomized order. For each day, individual slopes for the decrease in radioactivity were calculated, reflecting mucus transport in the peripheral, central, and the whole lung region. RESULTS:Significant differences in slopes were found between the control day and the cough day in the peripheral lung region for the interval 0 to 30 minutes and in the whole lung region for the interval 0 to 30 minutes and 0 to 45 minutes. The improvement of mucus clearance due to coughing, however, was relatively small in these patients, only 3% after 45 minutes: from 4% whole lung clearance during quiet breathing to 7% whole lung clearance during coughing. CONCLUSION:Tetraplegic patients may achieve a statistically significant increase in their bronchial mucus transport by voluntary coughing.
[Cough from a cardiologic perspective].
Pavlicek-Bahlo Maryam,Hunziker Lukas
Therapeutische Umschau. Revue therapeutique
Cough from a cardiologic perspective A cough is at the efferent end of a complex reflex arc and, due to its well-known mechanical respiratory cleaning function, usually the first symptom prompting a pneumological clarification. However, the chemical and mechanical afferent neuronal parts of the reflex, the cough receptors, are distributed over a variety of organ systems, some of which directly and indirectly affect the heart. Cardiology therefore plays a central role in the clarification of coughs. In cardiology, a cough is most frequently caused by acute and chronic heart failure resulting from different types of cardiomyopathies. It can, however, be caused by other pathologies as well. The connection between cough and cardiac arrhythmia is interesting, although cough can be cause, consequence and therapy. Last but not least, almost all drugs frequently prescribed in cardiology can cause cough in one way or another. In addition, a cough is the current number 1 warning sign when it comes to COVID-19 infection. On the one hand, it must be differentiated from cardiac-induced coughs, but on the other hand it can also be closely related to them.
10.1024/0040-5930/a001257
Interactions of mechanically induced coughing and sneezing in cat.
Simera Michal,Poliacek Ivan,Dobrolubov Boris,Veternik Marcel,Plevkova Jana,Jakus Jan
Respiratory physiology & neurobiology
Mutual interactions of cough and sneeze were studied in 12 spontaneously breathing pentobarbitone anesthetized cats. Reflexes were induced by mechanical stimulation of the tracheobronchial and nasal airways, respectively. The amplitude of the styloglossus muscle EMG moving average during the sneeze expulsion was 16-fold higher than that during cough (p<0.01). Larger inspiratory efforts occurred during coughing (p<0.01) vs. those in sneeze. The number of reflexes during simultaneous mechanical stimulation of the nasal and tracheal airways was not altered significantly compared to controls (p>0.05) and there was no modulation in temporal characteristics of the behaviors. When both reflexes occurred during simultaneous stimuli the responses were classified as either sneeze or cough (no hybrid responses occurred). During simultaneous stimulation of both airway sites, peak diaphragm EMG and inspiratory esophageal pressures during sneezes were significantly increased. The expiratory maxima of esophageal pressure and amplitudes of abdominal EMGs were increased in coughs and sneezes during simultaneous mechanical stimulation trials compared to control reflexes.
10.1016/j.resp.2014.09.011
Non-pharmacological techniques for the extremes of the cough spectrum.
Spinou Arietta
Respiratory physiology & neurobiology
Cough can be viewed as a continuum where extremes represent disease phenotypes. Under this unified concept, non-pharmacological treatment for the extremes of the cough spectrum includes both cough augmentation and cough control techniques. Supporting the cough motor output and exercising the cognitive control on coughing are the main directions of these techniques. Cough augmentation can be provided to patients who present low ability to generate adequate peak cough flows, with the aim to develop the sheering forces that are essential for effective airway clearance. On the other hand, individuals with high cough sensitivity or frequency can practice techniques for cough control, which incorporates a combination of education, retraining and psychological support. These techniques aim to empower patients to increase their supramedulary control on cough. Although hypotheses that are generated by the physiology of cough can support most non-pharmacological techniques, their exact mechanisms of effectiveness remain unclear.
10.1016/j.resp.2018.03.006
Cough: what's in a name?
Widdicombe J,Fontana G
The European respiratory journal
The cough reflex (CR) and the expiration reflex (ER) are two defensive reflexes from the respiratory tract, the latter mainly from the larynx. Both are elicited by mechanical and chemical irritation of the airway mucosa, and are a characteristic of airway diseases, but they have different functions. The CR first draws air into the lungs, to accentuate the subsequent expulsive phase; the ER consists of a strong expiration, to prevent aspiration of material into the lungs. They have different sensory pathways, central nervous circuits, and physiological and pharmacological modulations. In practice, coughing often consists of a combination of the two reflexes, a cough bout, epoch or attack. Articles on cough usually do not distinguish between the two reflexes, or whether the coughs are single events or epochs; they usually only measure frequency of expiratory efforts, and neglect other aspects. Current methods for measuring and assessing cough are described, with indications of when the use of these methods may be important.
10.1183/09031936.06.00096905
Novel Method for Detecting Coughing Pigs with Audio-Visual Multimodality for Smart Agriculture Monitoring.
Sensors (Basel, Switzerland)
While the pig industry is crucial in global meat consumption, accounting for 34% of total consumption, respiratory diseases in pigs can cause substantial economic losses to pig farms. To alleviate this issue, we propose an advanced audio-visual monitoring system for the early detection of coughing, a key symptom of respiratory diseases in pigs, that will enhance disease management and animal welfare. The proposed system is structured into three key modules: the cough sound detection (CSD) module, which detects coughing sounds using audio data; the pig object detection (POD) module, which identifies individual pigs in video footage; and the coughing pig detection (CPD) module, which pinpoints which pigs are coughing among the detected pigs. These modules, using a multimodal approach, detect coughs from continuous audio streams amidst background noise and accurately pinpoint specific pens or individual pigs as the source. This method enables continuous 24/7 monitoring, leading to efficient action and reduced human labor stress. It achieved a substantial detection accuracy of 0.95 on practical data, validating its feasibility and applicability. The potential to enhance farm management and animal welfare is shown through proposed early disease detection.
10.3390/s24227232
Translating Cough Mechanisms Into Better Cough Suppressants.
Keller Jennifer A,McGovern Alice E,Mazzone Stuart B
Chest
Chronic cough is a significant problem, and in many patients cough remains refractive to both disease-specific therapies and current cough-suppressing medicines, creating a need for improved antitussive therapies. Most patients with chronic cough also display heightened sensitivity so that they experience a persistent sense of the need to cough, and often innocuous stimuli can trigger their coughing. This hypersensitivity underpins the newly described concept of cough hypersensitivity syndrome (CHS), a term that encapsulates the notion of common underlying mechanisms producing neuronal activation, sensitization and/or dysfunction, which are at the core of excessive coughing. Understanding these mechanisms has been a focus of recent research efforts in the field in the hope that new therapies can be developed to selectively target sensitized unproductive cough while maintaining the reflexive cough essential for airway protection. However, efforts to achieve this have been slower than expected, in part because of some significant challenges and limitations translating current cough models. In this review, we summarize recent advances in our understanding of the sensory circuits innervating the respiratory system that are important for cough, how cough sensory pathways become hypersensitive, and some of the recently described neural targets under development for treating chronic cough. We present the case that better use of current cough models or the development of new models, or both, is ultimately needed to advance our efforts to translate the discovery of basic cough mechanisms into effective medicines for treating patients with chronic cough.
10.1016/j.chest.2017.05.016
Replacing a double-lumen tube with a single-lumen tube or a laryngeal mask airway device to reduce coughing at emergence after thoracic surgery: a randomized controlled single-blind trial.
Tanoubi Issam,Sun Joanna Ng Man,Drolet Pierre,Fortier Louis-Philippe,Donati François
Canadian journal of anaesthesia = Journal canadien d'anesthesie
BACKGROUND:Coughing episodes occur frequently at extubation after thoracic surgery, and this may be due in part to the double-lumen tube (DLT). In this study, the DLT was replaced with either a single-lumen endotracheal tube (ETT) or a laryngeal mask airway (LMA) device or left in place, and the incidence of coughing at emergence was compared between the three groups. METHODS:Fifty-eight adults scheduled for thoracic surgery with a DLT were included. Exclusion criteria were an anticipated difficult airway, obesity, and contraindication to the use of an LMA ProSeal™ (LMA-P). After surgery but before emergence, patients were randomized to having the DLT (1) removed and replaced by an LMA-P (LMA-P Group), (2) removed and replaced by an ETT (ETT Group), or (3) left in place (DLT Group). The primary outcome was the number of coughing episodes at extubation. RESULTS:Among 184 patients screened, 124 did not meet inclusion criteria, and two patients, both in the ETT Group, were excluded after randomization, leaving 20, 18, and 20 patients in the LMA-P, ETT, and DLT Groups, respectively. There were fewer coughing episodes (median [quartiles]) in the LMA-P Group than in the DLT Group (0[0-1] vs 2[1-3], respectively; P = 0.01). In the DLT Group, 90% of patients coughed at least once. This incidence was not significantly different in the ETT Group (83%; P = 0.222) but was significantly reduced in the LMA-P Group (35%; P < 0.001). No patient had oxygen desaturation during airway exchange or at extubation. The incidence and severity of hoarseness and sore throat were similar in all groups. CONCLUSION:Coughing at extubation after thoracic surgery can be reduced if the DLT is replaced by an LMA-P before emergence. The number of patients in this trial was too small to evaluate the risks associated with exchanging the airway device. This trial was registered at ClinicalTrials.gov: NCT00925613.
10.1007/s12630-015-0403-2
How often do healthy people cough?
Respiratory research
Objective cough frequency has been reported in several respiratory conditions but the amount that healthy individuals cough daily is unclear. Seventy-nine healthy volunteers (38 males, median [IQR] age 41y [IQR 30-53]) completed 24-hour ambulatory cough monitoring (VitaloJAK™). The audio recording was filtered using a custom written algorithm to remove non-cough sounds and then all individual explosive cough sounds in the filtered file were tagged electronically by trained cough counters. Most coughing occurred during the day and cough numbers over 24 h were generally low (geometric mean of 4.6 coughs) but there was large variability; ranging from 0 to 136 coughs overall. Cough frequency was independent of participant characteristics apart from sex with males coughing significantly, 4-5 fold, more than females during the day and over 24 h (median [IQR] 16.1 [3.8-33.4] vs. 4.1 [1.0-15.0] total coughs; p = 0.015). This is the first report to describe cough frequency in a balanced group of healthy adults using an accurate cough monitoring system. The data reveal a further example of sexual dimorphism in cough, which warrants additional investigation.
10.1186/s12931-023-02585-1
Patient-reported experiences with refractory or unexplained chronic cough: a qualitative analysis.
Therapeutic advances in respiratory disease
BACKGROUND:Chronic cough, defined as a cough lasting 8 or more weeks, affects up to 10% of adults. Refractory chronic cough (RCC) is a cough that is uncontrolled despite comprehensive investigation and treatment of comorbid conditions while unexplained chronic cough (UCC) is a cough with no identifiable cause despite extensive evaluation of comorbid conditions. RCC and UCC are often poorly controlled. Understanding individuals' lived experience of the symptoms and impacts of these conditions may guide therapeutic strategies. OBJECTIVES:The primary objectives of this study were to assess respondents' perceptions of the key symptoms of RCC and UCC and the impacts of RCC and UCC and their symptoms on well-being, health-related quality of life, work productivity, and social relationships. DESIGN:Qualitative study. METHODS:This study enrolled 30 adults with physician-diagnosed RCC or UCC. Two trained qualitative researchers conducted individual, in-depth telephone interviews using a semi-structured interview guide. Interviews were audio-recorded, transcribed, coded, and systematically analyzed to identify content themes. RESULTS:A total of 15 respondents with RCC and 15 with UCC were included in the study. Many respondents had RCC or UCC for a long duration (median 9 years, range: 0-24). Half of the respondents reported having a coughing episode at least once daily. Only 40% of respondents reported that medication had improved their symptoms. In over half of the respondents, RCC or UCC hindered communication, caused embarrassment, frustration, and worry, and lowered quality of life. Perceptions of meaningful treatment benefits in RCC or UCC varied widely across respondents. CONCLUSION:RCC and UCC remained poorly managed in many individuals and were associated with a wide range of symptoms and cough triggers that hindered daily activities and reduced emotional well-being. Understanding individuals' lived experiences may inform the development of RCC and UCC therapeutic strategies.
10.1177/17534666241236025
Coughing children in family practice and primary care: a systematic review of prevalence, aetiology and prognosis.
BMC pediatrics
BACKGROUND:For evidence-based decision making, primary care physicians need to have specific and reliable information on the pre-test probabilities of underlying diseases and a symptom's course. We performed a systematic review of symptom-evaluating studies in primary care, following three research questions: (1) What is the prevalence of the symptom cough in children consulting primary care physicians? (2) What are the underlying aetiologies of cough and the respective frequencies? (3) What is the prognosis of children with cough? METHODS:Following a pre-defined algorithm and independent double reviewer ratings we searched MEDLINE and EMBASE. All quantitative original research articles in English, French or German were included if they focused on unselected study populations of children consulting a primary care physician for cough. We used the random effects model for meta-analysis in subgroups, if justifiable in terms of heterogeneity. RESULTS:We identified 14 eligible studies on prevalence, five on aetiology and one on prognosis. Prevalence estimates varied between 4.7 and 23.3% of all reasons for an encounter, or up to estimates of 60% when related to patients or consultations. Cough in children is more frequent than in adults, with lowest prevalences in adolescents and in summer. Acute cough is mostly caused by upper respiratory tract infections (62.4%) and bronchitis (33.3%); subacute or chronic cough by recurrent respiratory tract infection (27.7%), asthma (up to 50.4% in cough persisting more than 3 weeks), and pertussis (37.2%). Potentially serious diseases like croup, pneumonia or tuberculosis are scarce. In children with subacute and chronic cough the total duration of cough ranged from 24 to 192 days. About 62.3% of children suffering from prolonged cough are still coughing two months after the beginning of symptoms. CONCLUSION:Cough is one of the most frequent reasons for an encounter in primary care. Our findings fit in with current guideline recommendations supporting a thoughtful wait-and-see approach in acute cough and a special awareness in chronic cough of the possibility of asthma and pertussis. Further evidence of aetiological pre-test probabilities is needed to assess the diagnostic gain based on patient history and clinical signs for differential diagnoses of cough in children.
10.1186/s12887-021-02739-4
Failure of nebulized irritant, acidic, or hypotonic solutions or external mechanical stimulation of the trachea to consistently induce coughing in healthy, awake dogs.
Boyle Tonya E,Hawkins Eleanor C,Davis Jennifer L,Robertson Ian D
Canadian journal of veterinary research = Revue canadienne de recherche veterinaire
A useful approach for evaluating antitussive drugs in humans is to determine the sensitivity of the cough reflex to a standard challenge. The purpose of this study was to determine if methods used to induce coughing in humans would be effective when used on awake, untrained, healthy dogs for future application in therapeutic trials involving dogs with spontaneous disease. Methods tested were: mechanically stimulating the trachea by digital compression as well as by vibration from an electric shaver, neck massager, and palm sander (11 dogs), and administering nebulized irritant (3000 μM capsaicin), acidic (1 M citric acid), and hypotonic (deionized water) solutions using face masks (4 dogs). The threshold for success was defined as induction of at least 2 moderate or strong coughs in at least 75% of the dogs. None of the methods tested was successful. Digital compression induced soft (n = 2) or moderate (n = 1) coughing in 3 of 11 dogs tested. Nebulization of citric acid induced 1 soft cough in 1 of 4 dogs. It was concluded that coughing cannot be successfully induced in awake, healthy dogs using methods that are successful in humans. Other strategies must be developed so that cough sensitivity can be objectively and non-invasively measured in dogs for clinical research purposes.
Pharmacology of cough in palliative care.
Morice Alyn H,Shanks Gabriella
Current opinion in supportive and palliative care
PURPOSE OF REVIEW:Cough is a common and distressing symptom. It has a marked decrement on quality-of-life particularly in the arena of palliative care where coexisting symptoms such as pain may be exacerbated. Whilst local definitive treatment may alleviate coughing it usually requires general measures. The purpose of the review is to assess the current evidence relating to the pharmacological management of cough. RECENT FINDINGS:Key to understanding cough is the realization that most cough is because of a hypersensitivity of the afferent vagus nerve. Cough suppression with opioids and first-generation antihistamines may produce relief. However, much cough in palliative medicine is caused by unrecognized nonacid reflux and aspiration. Promotility agents may be dramatically effective at both preventing cough and recurrent aspiration. SUMMARY:The implications of this review will aid practitioners understanding of cough in a variety of settings, including palliative care.
10.1097/SPC.0000000000000279
How much coughing is normal?
Munyard P,Bush A
Archives of disease in childhood
A new multiparametric device (RBC-7) was used for recording cough in ambulatory children over a 24 hour period. The number of coughs and the pattern of coughing can easily be studied with the aid of a personal computer and dedicated computer software. Forty one 'normal' children were recorded, identified from a primary school with the aid of a questionnaire. They were free from any respiratory infection for one month, and had a normal examination and spirometry immediately before recording. Cough frequency was 11.3, range 1 to 34, cough episodes per 24 hours. This was unaffected by passive smoking or the presence of furry pets in the home. Nocturnal and prolonged coughing was unusual in these children. The device was highly acceptable to the children, and no adverse effects were reported. Such objective data on cough outside the laboratory setting are unique, help to determine what is normal, and may help in the diagnosis and assessment of many respiratory diseases.
10.1136/adc.74.6.531
Pharmacology of Bradykinin-Evoked Coughing in Guinea Pigs.
The Journal of pharmacology and experimental therapeutics
Bradykinin has been implicated as a mediator of the acute pathophysiological and inflammatory consequences of respiratory tract infections and in exacerbations of chronic diseases such as asthma. Bradykinin may also be a trigger for the coughing associated with these and other conditions. We have thus set out to evaluate the pharmacology of bradykinin-evoked coughing in guinea pigs. When inhaled, bradykinin induced paroxysmal coughing that was abolished by the bradykinin B2 receptor antagonist HOE 140. These cough responses rapidly desensitized, consistent with reports of B2 receptor desensitization. Bradykinin-evoked cough was potentiated by inhibition of both neutral endopeptidase and angiotensin-converting enzyme (with thiorphan and captopril, respectively), but was largely unaffected by muscarinic or thromboxane receptor blockade (atropine and ICI 192605), cyclooxygenase, or nitric oxide synthase inhibition (meclofenamic acid and N(G)-nitro-L-arginine). Calcium influx studies in bronchopulmonary vagal afferent neurons dissociated from vagal sensory ganglia indicated that the tachykinin-containing C-fibers arising from the jugular ganglia mediate bradykinin-evoked coughing. Also implicating the jugular C-fibers was the observation that simultaneous blockade of neurokinin2 (NK2; SR48968) and NK3 (SR142801 or SB223412) receptors nearly abolished the bradykinin-evoked cough responses. The data suggest that bradykinin induces coughing in guinea pigs by activating B2 receptors on bronchopulmonary C-fibers. We speculate that therapeutics targeting the actions of bradykinin may prove useful in the treatment of cough.
10.1124/jpet.115.230383
Fentanyl-induced cough--pathophysiology and prevention.
El Baissari Mabelle C Tannous,Taha Samar K,Siddik-Sayyid Sahar M
Middle East journal of anaesthesiology
Many reports have demonstrated that intravenous administration of a bolus of fentanyl at induction of anesthesia can cause coughing with varying degrees. This cough can be benign, but sometimes it causes undesirable side effects including an increase in intraabdominal, intracranial or intraocular pressure. Many studies demonstrated that the incidence and severity of fentanyl-induced cough could be related to age, ethnicity, history of smoking, as well as to the rate, route, dose and concentration of fentanyl administered. This cough was described by several mechanisms including an inhibition of central sympathetic system leading to vagal predominance, reflex bronchonstriction after the stimulation of tracheobronchial tree receptors, or histamine release. The efficacy of several measures to avoid fentanyl-induced cough have been demonstrated, and several anesthetics adjuncts can be given prior to fentanyl administration aiming at decreasing this unwanted side effect.
Morphine for treatment of cough in idiopathic pulmonary fibrosis (PACIFY COUGH): a prospective, multicentre, randomised, double-blind, placebo-controlled, two-way crossover trial.
The Lancet. Respiratory medicine
BACKGROUND:Idiopathic pulmonary fibrosis is a progressive fibrotic lung disease, with most patients reporting cough. Currently, there are no proven treatments. We examined the use of low dose controlled-release morphine compared with placebo as an antitussive therapy in individuals with idiopathic pulmonary fibrosis. METHODS:The PACIFY COUGH study is a phase 2, multicentre, randomised, double-blind, placebo-controlled, two-way crossover trial done in three specialist centres in the UK. Eligible patients aged 40-90 years had a diagnosis of idiopathic pulmonary fibrosis within 5 years, self-reported cough (lasting >8 weeks), and a cough visual analogue scale (VAS) score of 30 mm or higher. Patients were randomly assigned (1:1) to placebo twice daily or controlled-release morphine 5 mg orally twice daily for 14 days followed by crossover after a 7-day washout period. Patients were randomised sequentially to a sequence group defining the order in which morphine and placebo were to be given, according to a computer-generated schedule. Patients, investigators, study nurses, and pharmacy personnel were masked to treatment allocation. The primary endpoint was percentage change in objective awake cough frequency (coughs per h) from baseline as assessed by objective digital cough monitoring at day 14 of treatment in the intention-to-treat population, which included all randomised participants. Safety data were summarised for all patients who took at least one study drug and did not withdraw consent. This study was registered at ClinicalTrials.gov, NCT04429516, and has been completed. FINDINGS:Between Dec 17, 2020, and March 21, 2023, 47 participants were assessed for eligibility and 44 were enrolled and randomly allocated to treatment. Mean age was 71 (SD 7·4) years, and 31 (70%) of 44 participants were male and 13 (30%) were female. Lung function was moderately impaired; mean forced vital capacity (FVC) was 2·7 L (SD 0·76), mean predicted FVC was 82% (17·3), and mean predicted diffusion capacity of carbon monoxide was 48% (10·9). Of the 44 patients who were randomised, 43 completed morphine treatment and 41 completed placebo treatment. In the intention-to-treat analysis, morphine reduced objective awake cough frequency by 39·4% (95% CI -54·4 to -19·4; p=0·0005) compared with placebo. Mean daytime cough frequency reduced from 21·6 (SE 1·2) coughs per h at baseline to 12·8 (1·2) coughs per h with morphine, whereas cough rates did not change with placebo (21·5 [SE 1·2] coughs per h to 20·6 [1·2] coughs per h). Overall treatment adherence was 98% in the morphine group and 98% in the placebo group. Adverse events were observed in 17 (40%) of 43 participants in the morphine group and six (14%) of 42 patients in the placebo group. The main side-effects of morphine were nausea (six [14%] of 43 participants) and constipation (nine [21%] of 43). One serious adverse event (death) occurred in the placebo group. INTERPRETATION:In patients with cough related to idiopathic pulmonary fibrosis, low dose controlled-release morphine significantly reduced objective cough counts over 14 days compared with placebo. Morphine shows promise as an effective treatment to palliate cough in patients with idiopathic pulmonary fibrosis, and longer term studies should be the focus of future research. FUNDING:The Jon Moulton Charity Trust.
10.1016/S2213-2600(23)00432-0
Ictal coughing: Clinical features and differential diagnoses.
Asadi-Pooya Ali A,Shabo Leah,Wyeth Dale,Nei Maromi
Epilepsy & behavior : E&B
PURPOSE:To describe a series of patients with ictal coughing to estimate its occurrence and characterize the clinical features and differential diagnoses. METHODS:We retrospectively reviewed all the long-term video-EEG reports from Jefferson Comprehensive Epilepsy Center over a 7-year period (2010-2016) for the occurrence of the term "cough" in the text body. All the extracted reports were reviewed and patients with at least one documented ictal coughing at the epilepsy monitoring unit (EMU) were included in the study. RESULTS:During the study period, 2487 patients were investigated at our EMU. Seven patients (0.28%) had at least one documented seizure accompanied by coughing. Four patients (0.16%) had epilepsy and three patients (0.12%) had psychogenic nonepileptic seizures (PNES). All patients with epilepsy had focal onset epilepsy; ictal coughing was not associated with any particular localization or lateralization. CONCLUSION:We add to the literature on ictal coughing by providing additional information on its differential diagnosis and clinical features. Ictal coughing is a rare finding among patients evaluated at the EMUs. The differential diagnoses for ictal coughing include epilepsy and PNES. Epileptic ictal coughing is a rare semiological finding in patients with epilepsy and when present, it is invariably associated with focal epilepsy.
10.1016/j.yebeh.2017.04.044
[Coughing].
Nederlands tijdschrift voor geneeskunde
Coughing may impair the quality of life, for instance by interfering with sleep or social interactions. Acute cough is almost invariably caused by a viral respiratory tract infection and seldom warrants medical consultation or treatment. Red flags in cough (haemoptysis, high fever or severe illness) may be indicative of a life threatening underlying disease. Wet and dry cough often have the same aetiology, and a different approach is therefore not needed.
Cough response to aspiration in thin and thick fluids during FEES in hospitalized inpatients.
Miles Anna,McFarlane Mary,Scott Samantha,Hunting Alexandra
International journal of language & communication disorders
BACKGROUND:The modifications of fluid viscosity and/or volume are common strategies in dysphagia management, with increased viscosity or reduced volume intended to reduce aspiration. Little attention has been given to whether cough response to aspiration varies across different viscosities and volumes. AIMS:This prospective observational study investigated aspiration prevalence and cough response to aspiration in thin and thick fluids of two different volumes in patients referred for flexible endoscopic evaluation of swallowing (FEES) in an acute hospital setting. METHODS & PROCEDURES:Consecutive inpatients (N = 180) referred for FEES were recruited: stroke 51 (28%); other neurological condition (traumatic brain injury, progressive neurological) 33 (18%); cardiovascular critical care 51 (28%); respiratory illness/condition 23 (13%); spinal injury 9 (5%); and other 13 (7%). A standardized protocol was completed on 268 FEES (180 first FEES, 88 repeat FEES). Penetration-aspiration scale (PAS) scores were obtained for thin and mildly thick fluids at two volumes: 5 ml teaspoon and 50 ml continuous drinking. OUTCOMES & RESULTS:The incidence of aspiration (PAS > 5) was 32% for thin fluids and 18% for thick fluids. There was a significant association between cough response to aspiration and viscosity (p < .001) and volume (p < .001). There was a higher prevalence of silent aspiration in thick fluids than thin fluids. Some patients demonstrated variable cough responsiveness to aspiration across different viscosities and volumes. With 5 ml volumes, 20 patients coughed when they aspirated thin fluids but silently aspirated thick fluids. In comparison, discrepancies in the 50 ml volume were fewer, with three patients coughing when they aspirated thin fluids but silently aspirating thick fluids. CONCLUSIONS & IMPLICATIONS:Cough response to aspiration differs across bolus volumes and viscosities. The finding of inconsistent cough response to aspiration in some patients strongly encourages the use of instrumental assessment to guide decisions regarding diet modifications.
10.1111/1460-6984.12401
A novel approach to studying the relationship between subjective and objective measures of cough.
Kelsall Angela,Houghton Lesley A,Jones Helen,Decalmer Samantha,McGuinness Kevin,Smith Jaclyn A
Chest
BACKGROUND:Currently, no data are available on the relationship between changes in objective and subjective measures of cough, the magnitude of change in cough frequency perceived by patients as clinically meaningful, or the sample sizes required to show significant changes in cough therapeutic trials. Because patients anecdotally report reductions in cough severity while undergoing esophageal testing, we aimed to address these issues by assessing objective and subjective measures of cough with and without an esophageal catheter. METHODS:Twenty-four-hour cough monitoring was performed on two occasions, with and without esophageal impedance/pH monitoring in 62 patients with chronic cough (mean age 56.8 years [SD±10.8]; 43 women; median cough duration 3.3 years [interquartile range (IQR), 2.0-10.0]). Cough was assessed objectively measuring coughs per hour and subjectively using a numerical cough score and a visual analog scale (VAS), scored separately for day and night, and then averaged to represent each 24-h period. RESULTS:Objective cough frequency was reduced by a median of 33.3% (IQR, -68.8% to -13.0%; P<.001) with the catheter. The averaged day and night cough scores and VAS scores also significantly decreased, but changes in these did not correlate with decreases in cough frequency. Sample-size calculations suggested that crossover designs using objective cough frequency may be preferable in therapeutic trials. CONCLUSIONS:These observations provide useful information on the reduction in objective cough frequency scored as an improvement by patients with chronic cough and offer guidance for the design and powering of future therapeutic trials. TRIAL REGISTRY:ISRCTN; No.: ISRCTN62337037; URL: http://www.controlled-trials.com.
10.1378/chest.10-0438
Therapy for cough: active agents.
Chung K F,Chang A B
Pulmonary pharmacology & therapeutics
Cough is an important defensive reflex of the upper airway and is also a very common symptom of respiratory disease. Cough after an upper respiratory virus infection is transient, and persistent cough is associated with a whole range of conditions such as asthma, rhino-sinusitis, gastro-oesophageal reflux. Treatment directed at these conditions may improve the associated cough. There is often a need, however, to control cough itself, whatever the cause. The most effective drugs in this class are the opioids, such as morphine, codeine or pholcodeine, but at effective doses they have side-effects such as drowsiness, nausea, constipation and physical dependence. Investigations into the cough reflex and into the potential mechanisms of sensitised cough reflex have uncovered several potential targets for novel drugs. New opioids such as k- and d-receptor agonists apart from m-agonists have been developed, in addition to non-opioid, nociceptin. Neurokinin receptor antagonists, bradykinin receptor antagonists, vanilloid receptor VR-1 antagonists may be beneficial by blocking effects of tachykinins, and sensory nerve activation. Local anaesthetics, blockers of sodium-dependent channels, and maxi-K CA2+-dependent channel activators of afferent nerves are inhibitors of the cough reflex. Some of these novel agents may act centrally or peripherally or at both sites as antitussives. Large scale trials of these novel compounds have not been tried in cough in man, but there is a serious need for more effective antitussives devoid of side-effects.
10.1006/pupt.2002.0342
[Effectiveness and safety evaluation of a cough stimulation device in early postoperative respiratory rehabilitation in cardiac surgery patients].
Eremenko A A,Ryabova D V,Komnov R D,Chervinskaya A V
Voprosy kurortologii, fizioterapii, i lechebnoi fizicheskoi kultury
Postoperative respiratory complications in cardiac surgery patients occur in 22-30% of cases, mostly associated with ineffective cough and evacuation of bronchial secretion. OBJECTIVE:To evaluate the effectiveness and safety of cough stimulation using the mechanical in- and exsufflator in the early postoperative period in cardiac surgery patients. MATERIAL AND METHODS:The study included 37 patients; mean age was 57±12.3 years. Inclusion criteria: age over 18 years; post-extubation spontaneous breathing; fully conscious and cooperative; adequate gas exchange with oxygen therapy; adequate pain control (2 points or less on 10-point visual analogue scale). Exclusion criteria: need for re-intubation and mechanical ventilation; noninvasive mask ventilation; high-flow oxygen therapy; acute cerebrovascular event; uncontrolled bleeding; heart failure (inotropic score over 10); shock; need of extracorporeal blood purification; neuromuscular disease; pneumothorax, hydro- or hemothorax. Cough stimulation was performed using the mechanical in- and exsufflator Comfort Cough Plus («Seoil Pacific Corporation», Republic of Korea). The device provides cough stimulation after high-frequency vibrations transmitted through a special vest and lung tissue recruiting by changing the airways pressure of the gas mixture, delivered through the anesthesia face mask. RESULTS:Cough stimulation device use was associated with an increase in the cough effectiveness; the number of patients with productive cough increased 8-fold, from 4 (10.8%) to 32 (86.4%), =0.0000. The increase of blood oxygen saturation (SpO2) on room air from 92% to 96% (=0.000001) and inspiratory capacity (IC) from 750 mL to 1200 mL (=0.000002) was observed. The number of patients with IC of 1200-1500 mL increased 3-fold, and those with an IC over 1500 mL increased 2.6-fold. The proportion of patients with low oxygenation (SpO less than 92%) decreased 5-fold after the procedure (=0.0011). Good tolerability and no side effects of the procedure were noted in all patients. CONCLUSION:Impaired sputum expectoration early after cardiac surgery is observed in most patients and may cause low oxygenation. The main effects of the cough stimulation device were improvement of sputum expectoration and an increase in oxygenation. An increase in blood oxygen saturation and inspiratory capacity after a single procedure with this device was demonstrated. It resulted in a significantly decreased proportion of patients with respiratory insufficiency. No adverse effects of the procedure were observed.
10.17116/kurort20219806217
Voluntary Cough Testing as a Clinical Indicator of Airway Protection in Cervical Spinal Cord Injury.
The Laryngoscope
OBJECTIVE:Voluntary cough testing (VCT) may be useful for determining aspiration risk in neurogenic dysphagia; however, has yet to be investigated in traumatic cervical spinal cord injury (tCSCI). The study explored if VCT may elucidate swallowing safety and kinematics related to airway protection in tCSCI survivors. METHODS:Ten inpatients, 13-73 days post-tCSCI (7 incomplete injuries), completed VCT and a modified barium swallowing study that was analyzed via the Penetration Aspiration Scale (PAS) and norm-referenced measures of swallowing events related to airway protection. Spearman rho correlations explored relations among cough airflow, median PAS, and airway protection. Mann-Whitney U tests explored group differences based on clinical airway invasion (PAS > 2) and receiver operating characteristic statistics probed the sensitivity/specificity of VCT measures. RESULTS:Safe (PAS > 2) and unsafe swallowers differed by cough volume acceleration (CVA) for the total sample and by inspiratory duration for incomplete injuries (p = 0.03, r > 0.7). A cut-off value of 24.8 L/s for CVA predicted airway invasion (AUC = 0.917, p = 0.03) with sensitivity = 100%/specificity = 75%. CVA correlated with delayed laryngeal vestibule closure during swallowing for both the total sample and for incomplete injuries (r > 0.6, p < 0.05). Blunted peak flow and prolonged cough phases were associated with disordered laryngeal kinematics and prolonged bolus transit during swallowing (p < 0.05). CONCLUSIONS:Reduced CVA, blunted peak flow, and prolonged cough phases reflected PAS and disrupted mechanisms of airway protection in tCSCI survivors, demonstrating promise for VCT as a clinical assessment for post-tCSCI dysphagia. LEVEL OF EVIDENCE:3 Laryngoscope, 133:1434-1441, 2023.
10.1002/lary.30369
Adjunctive vagus nerve stimulation for treatment-resistant depression: a preliminary study.
International journal of psychiatry in clinical practice
BACKGROUND:This study is the first to assess the safety and therapeutic efficacy of vagus nerve stimulation (VNS) as an adjunctive treatment for Chinese patients suffering from treatment-resistant depression (TRD). METHODS:A total of seven patients with TRD underwent surgical implantation of a VNS device were followed over a 9-month period. The 24-item Hamilton Rating Scale for Depression (HAMD-24) and the 14-item Hamilton Anxiety Scale (HAMA) were used to assess depressive and anxiety symptoms, respectively. Neurocognitive function was measured with the Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale (WMS). RESULTS:After 3 months of treatment with VNS, the antidepressant response and remission rates were 42.9% and 28.6%, respectively. After 9 months of treatment with VNS, the response and remission rates increased to 85.7% and 57.1%, respectively. Significant time main effects were identified for HAMD-24 scores, HAMA scores, the WMS memory quotient, and the full intelligence quotients measured with the WAIS (all s < 0.05). The most frequent adverse effects of VNS treatment were voice alteration (100%) and cough frequency increase (71.4%). CONCLUSION:This preliminary study indicated that adjunctive VNS was effective and safe in treating Chinese patients who were suffering from TRD, and its efficacy increased with time.Key pointsThere is positive evidence to support the role of VNS as an adjunctive treatment in Chinese patients with TRD.The antidepressant efficacy of adjunctive VNS for Chinese patients with TRD increased with time.The most frequent adverse effects of VNS treatment were voice alteration and cough frequency increase.
10.1080/13651501.2021.2019789
A cross sectional study to determine the prevalence of cough and its impact in patients with lung cancer: a patient unmet need.
BMC cancer
BACKGROUND:There is absence of literature related to cough prevalence and its characteristics in lung cancer patients, with information deriving only from broader symptoms occurrence studies. The aims of this study were to provide a snapshot of the prevalence of all-cause-cough in lung cancer patients and to characterise cough in terms of its impact and severity. METHODS:A cross-sectional study recruiting consecutive lung cancer patients over a pre-defined period of time and using cough-specific validated tools in a tertiary referral centre in the UK, including a cough severity VAS and the Manchester Cough in Lung Cancer scale (MCLCS). RESULTS:Data was collected from 202 patients. All-cause cough prevalence was 57% (through VAS) both in the screened (N = 223) and research (N = 202) population or 67% (through the MCLCS), and cough severity was moderate at a mean of 32 mm (in a 100 mm VAS). Age, sex, smoking status, lung cancer histology, stage and comorbidities were not associated with cough prevalence. The only variable associated with lower cough reports was being 'on anticancer treatment'; fewer patients on treatment reported a cough (40%) compared to those off treatment (54%) (p = 0.04). The impact of cough (as measured by MCLCS) was also significant (mean score = 22). About 18% of patients felt moderate/severe distress from their cough and about 15% often or always reported disturbed sleep due to coughing. Half the patients felt their cough warranted treatment. CONCLUSIONS:Cough is a common symptom in lung cancer with considerable impact on patients' lives. Cough presence and severity should regularly be assessed in clinical practice. There is an urgent need to focus on developing more potent antitussive treatments and improve the management of this complex and distressing symptom.
10.1186/s12885-019-6451-1
Fatigue, dyspnea, and cough comprise a persistent symptom cluster up to five years after diagnosis with lung cancer.
Cheville Andrea L,Novotny Paul J,Sloan Jeffrey A,Basford Jeffrey R,Wampfler Jason A,Garces Yolanda I,Jatoi Aminah,Yang Ping
Journal of pain and symptom management
CONTEXT:Aggregates of concurrent symptoms, known as symptom clusters (SxCls), have been described in predominantly cross-sectional samples of lung cancer (LC) patients undergoing treatment. OBJECTIVES:The objective of this study was to delineate SxCls in LC survivors up to five years after diagnosis, investigate their stability over time, and identify determinants of SxCl development and resolution. METHODS:A sensitivity approach involving multiple exploratory and confirmatory analyses was applied to an eight-year prospective cohort study that annually assessed 2405 patients with LC for symptom burden with the Lung Cancer Symptom Scale and Linear Analogue Self-Assessment. RESULTS:A single robust SxCl of fatigue, cough, and dyspnea was identified in 14.6%, 12.9%, 14.1%, 14.6%, and 15.4% of participants at Years 1-5 after diagnosis, respectively. Participants with the SxCl (SxCl (+)) were more likely to die than those without it; but this tendency diminished over time. SxCl persistence varied, with ≥40% of surviving patients annually transitioning to or from the SxCl(+) state until Year 4, after which the SxCl became increasingly stable. The SxCl was more likely to develop among male survivors who underwent surgery, received radiation, and were current smokers. CONCLUSION:A single SxCl comprising dyspnea, fatigue, and cough has a stable prevalence among LC survivors up to five years after diagnosis but is not stable among individuals. Initially, after diagnosis, the SxCl is associated with a greater risk of death; however, after Year 2, the SxCl becomes increasingly stable and provides a marker for parenchymal lung injury.
10.1016/j.jpainsymman.2010.10.257
Methacholine-induced cough as an indicator of bronchodilator-responsive cough.
Ohkura Noriyuki,Fujimura Masaki,Hara Johsuke,Nakade Yusuke,Abo Miki,Sone Takashi,Kimura Hideharu,Kasahara Kazuo
Pulmonary pharmacology & therapeutics
BACKGROUND:Cough variant asthma (CVA) is the most common cause of chronic cough and responds well to bronchodilator therapy. Previous studies on methacholine -induced cough have shown that heightened cough response due to bronchoconstriction is a feature of CVA. The aim of this study was to assess Mch-induced cough as an indicator of bronchodilator-responsive cough (BRC). METHODS:This was a single-center retrospective study of prolonged/chronic cough cases who underwent evaluation via spirometry, FeNO and bronchial challenge testing using Mch and capsaicin (C5). Resultant bronchoconstriction after Mch challenge was assessed by flow-volume curves measuring the expiratory flow of the partial flow-volume curve 40% above residual volume (PEF) and FEV. BRC was defined as a decrease in cough with bronchodilator therapy by 30% or more on a visual analog scoring scale. RESULTS:Of the 100 patients evaluated, 63 were diagnosed with BRC. Mch-induced cough at a decrease in PEF of 35% (PC-PEF) was predictive of BRC on AUROC analysis with an AUC of 0.82 (95% CI 0.73-0.90) and cut-off of 24. The AUC for C5, FeNO and PC-FEV were 0.65, 0.47, and 0.58, respectively. CONCLUSION:Compared to C5, FeNO and PC-FEV, Mch-induced cough better supports a diagnosis of BRC.
10.1016/j.pupt.2020.101962
Urge to cough with voluntary suppression following mechanical pharyngeal stimulation.
Hegland K W,Pitts T,Bolser D C,Davenport P W
Bratislavske lekarske listy
OBJECTIVE:The goal of this project was to determine if mechanical stimulation to the posterolateral oropharynx would elicit the urge-to-cough and/or cough. BACKGROUND:Inhaled agents, such as capsaicin and citric acid, readily produce coughing and the sensation of urge-to-cough. Areas below the glottis are thought to be the primary sensory mediators of these responses, however it is unknown if there are specific areas in the oropharynx or laryngopharynx that are important for the sensation and production of coughing. METHODS:Paired-pulse air puffs were delivered to the posterolateral oropharyngeal walls of 11 healthy adults (5 men, 6 women) between the ages of 18 and 30 years. Air puffs were delivered via custom mouthpiece in 4 trials, 50 sets per trial. Instances of cough were recorded, and a modified Borg scale was used to gauge urge-to-cough throughout each trial. RESULTS:Instances of cough were recorded in 12/37 trials, and the sensation of an urge-to-cough was present in 25/37 trials. No motor cough response was elicited with an urge-to-cough rating less than 2.4 on the modified Borg scale. A trend towards higher urge-to-cough was noted for later (3rd and 4th) trials. CONCLUSIONS:Oropharyngeal mechanical stimulation elicits urge-to-cough and cough in healthy young adults. Like other methods to elicit coughing, the motor and sensory thresholds are different using the oropharyngeal air-puff stimuli. Further, it appears there is a sensitization to the air puff stimuli with later trials associated with stronger urge-to-cough and higher likelihood of coughing versus the first and second trial (Tab. 1, Fig. 5, Ref. 21).
Development of the Rapid Cough Questionnaire: Key item identification.
Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology
BACKGROUND:The Leicester Cough Questionnaire (LCQ) is a reliable tool for measuring the multidimensional impact of cough on patients' quality of life; however, its scoring algorithm is lengthy and complex for routine clinical use. OBJECTIVE:The study aimed to develop a simplified version of the LCQ, the Rapid Cough Questionnaire (RCQ), as a substitue in clinical practice and validate the RCQ using an independent cohort. METHODS:To select items for the RCQ score, a correlation network was used to determine the items from each domain that were strongly correlated with the total LCQ score. The final items for the RCQ were selected on the basis of the centrality of the node degree, betweenness, and closeness in the correlation network. RESULTS:The RCQ score was derived from 3 items: tiredness (LCQ3) in the physical domain, the feeling of being fed up (LCQ13) in the psychological domain, and annoyance with partner/family/friends (LCQ19) in the social domain. The correlation between the LCQ and RCQ was high, with a coefficient of 0.93 (P < .001). The mean score of the RCQ was 11.2 ± 3.2, with scores ranging from 5.15 to 19.55. The minimal clinically important difference in the RCQ score was calculated to be 1.6 using a distribution-based method. The concurrent validity of the LCQ and the RCQ with cough numeric rating scale was similar. In the validation cohort, the correlation between the LCQ and RCQ scores was consistent regardless of sex and etiology. CONCLUSION:The RCQ score, which is concise, reliable, and valid, can be a valuable tool for patient assessment, particularly in clinical practice.
10.1016/j.anai.2023.12.025
Effect of anti-reflux treatment on gastroesophageal reflux-associated chronic cough: Implications of neurogenic and neutrophilic inflammation.
Takeda Norihisa,Takemura Masaya,Kanemitsu Yoshihiro,Hijikata Hisatoshi,Fukumitsu Kensuke,Asano Takamitsu,Yamaba Yusuke,Suzuki Motohiko,Kubota Eiji,Kamiya Takeshi,Ueda Takashi,Niimi Akio
The Journal of asthma : official journal of the Association for the Care of Asthma
Gastroesophageal reflux disease (GERD) is an important cause of chronic cough. Substance P (SP) has been implicated in the pathophysiology of cough. Proton pump inhibitors (PPIs) and prokinetic agents are the current treatment for GER-associated cough. The aim was to evaluate the effects of anti-reflux treatment and its associations with cellular and neurogenic inflammation. Thirty-seven patients with GER-associated cough suspected based on characteristic symptoms such as heartburn and worsening of cough by phonation and rising were recruited. A PPI, rabeprazole 20 mg daily, and a prokinetic agent, itopride 50 mg t.i.d., were administered for 4 weeks in a prospective, observational manner. Before and after treatment, subjective cough measures [visual analog scale (VAS) and the Japanese version of the Leicester Cough Questionnaire (J-LCQ)], the modified frequency scale for the symptoms of GERD [FSSG, consisting of 2 domains: acid-reflux (AR) and functional dyspepsia symptoms], sputum and plasma SP levels, and sputum cell differentials were examined. Patients with good response to treatment [Δ (decrease of) VAS >15 mm; = 21) were compared with poor responders (ΔVAS ≤15 mm). Anti-reflux treatment significantly improved the cough VAS, J-LCQ, and AR symptoms, and ΔVAS and ΔAR were significantly correlated. Decreases of plasma and sputum SP levels and sputum neutrophil counts were significantly greater in responders than in poor responders. Both baseline values and post-treatment changes of plasma SP and sputum neutrophils were significantly correlated for all patients. Successful treatment of GER-associated cough may be associated with the attenuation of neurogenic and neutrophilic inflammation.
10.1080/02770903.2019.1641204
Comparative analysis of clinical profile: Chronic cough vs paradoxical vocal fold motion.
Hartley Naomi A,Petty Brian E,Johnson Bethany,Thibeault Susan L
Respiratory medicine
BACKGROUND:Ongoing contention surrounding typical demographic and clinical attributes of chronic cough (CC) and paradoxical vocal fold motion (PVFM) impedes timely diagnosis and optimum patient care. Designed to reduce preventable patient morbidity through improved recognition and differentiation, the current study aimed to determine representative clinical profiles for CC and PVFM, with identification of distinctive attributes from the general population and risk factors associated with each diagnosis. METHODS:Self-reported medical questionnaires, demographic and lifestyle attributes of CC and PVFM cases from a disease-specific outcomes database were compared to US population data and published normative values. Univariate comparison and multivariate regression modelling of age, sex, alcohol intake, smoking, Reflux Symptom Index (RSI), Voice Handicap Index (VHI), and Generalized Anxiety Disorder 7-item Scale (GAD-7) determined distinguishing features between the clinical groups, including odds ratios for presenting with CC versus PVFM. RESULTS:Clinical profiles developed from 283 (128 CC, 155 PVFM) adults (18-91 years) were significantly different from the general population across each demographic, lifestyle and clinical variable (all p < .01), with the exception of obesity. Age (55.39 ± 13.54 vs 45.07 ± 16.51 years, p < .01) and mean RSI score (21.5 ± 9.02 vs 18.1 ± 9.08, p < .01) most reliably distinguished CC from PVFM, with those aged 60-69 years (OR = 9.45) most likely to be diagnosed with CC. CONCLUSIONS:Standard clinical profiles of CC and PVFM are distinct from the general population, aiding determination of relative probabilities and risk factors in the differential diagnostic process. Variations between CC and PVFM were subtle, reliably distinguished by age and relative severity of laryngopharyngeal reflux symptomatology.
10.1016/j.rmed.2015.10.007
Respiratory muscle training for multiple sclerosis.
The Cochrane database of systematic reviews
BACKGROUND:Multiple sclerosis (MS) is a chronic disease of the central nervous system, affecting approximately 2.5 million people worldwide. People with MS may experience limitations in muscular strength and endurance - including the respiratory muscles, affecting functional performance and exercise capacity. Respiratory muscle weakness can also lead to diminished performance on coughing, which may result in (aspiration) pneumonia or even acute ventilatory failure, complications that frequently cause death in MS. Training of the respiratory muscles might improve respiratory function and cough efficacy. OBJECTIVES:To assess the effects of respiratory muscle training versus any other type of training or no training for respiratory muscle function, pulmonary function and clinical outcomes in people with MS. SEARCH METHODS:We searched the Trials Register of the Cochrane Multiple Sclerosis and Rare Diseases of the Central Nervous System Group (3 February 2017), which contains trials from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, LILACS and the trial registry databases ClinicalTrials.gov and WHO International Clinical Trials Registry Platform. Two authors independently screened records yielded by the search, handsearched reference lists of review articles and primary studies, checked trial registers for protocols, and contacted experts in the field to identify further published or unpublished trials. SELECTION CRITERIA:We included randomized controlled trials (RCTs) that investigated the efficacy of respiratory muscle training versus any control in people with MS. DATA COLLECTION AND ANALYSIS:One reviewer extracted study characteristics and study data from included RCTs, and two other reviewers independently cross-checked all extracted data. Two review authors independently assessed risk of bias with the Cochrane 'Risk of bias' assessment tool. When at least two RCTs provided data for the same type of outcome, we performed meta-analyses. We assessed the certainty of the evidence according to the GRADE approach. MAIN RESULTS:We included six RCTs, comprising 195 participants with MS. Two RCTs investigated inspiratory muscle training with a threshold device; three RCTs, expiratory muscle training with a threshold device; and one RCT, regular breathing exercises. Eighteen participants (˜ 10%) dropped out; trials reported no serious adverse events.We pooled and analyzed data of 5 trials (N=137) for both inspiratory and expiratory muscle training, using a fixed-effect model for all but one outcome. Compared to no active control, meta-analysis showed that inspiratory muscle training resulted in no significant difference in maximal inspiratory pressure (mean difference (MD) 6.50 cmHO, 95% confidence interval (CI) -7.39 to 20.38, P = 0.36, I = 0%) or maximal expiratory pressure (MD -8.22 cmHO, 95% CI -26.20 to 9.77, P = 0.37, I = 0%), but there was a significant benefit on the predicted maximal inspiratory pressure (MD 20.92 cmHO, 95% CI 6.03 to 35.81, P = 0.006, I = 18%). Meta-analysis with a random-effects model failed to show a significant difference in predicted maximal expiratory pressure (MD 5.86 cmHO, 95% CI -10.63 to 22.35, P = 0.49, I = 55%). These studies did not report outcomes for health-related quality of life.Three RCTS compared expiratory muscle training versus no active control or sham training. Under a fixed-effect model, meta-analysis failed to show a significant difference between groups with regard to maximal expiratory pressure (MD 8.33 cmHO, 95% CI -0.93 to 17.59, P = 0.18, I = 42%) or maximal inspiratory pressure (MD 3.54 cmHO, 95% CI -5.04 to 12.12, P = 0.42, I = 41%). One trial assessed quality of life, finding no differences between groups.For all predetermined secondary outcomes, such as forced expiratory volume, forced vital capacity and peak flow pooling was not possible. However, two trials on inspiratory muscle training assessed fatigue using the Fatigue Severity Scale (range of scores 0-56 ), finding no difference between groups (MD, -0.28 points, 95% CI-0.95 to 0.39, P = 0.42, I = 0%). Due to the low number of studies included, we could not perform cumulative meta-analysis or subgroup analyses. It was not possible to perform a meta-analysis for adverse events, no serious adverse were mentioned in any of the included trials.The quality of evidence was low for all outcomes because of limitations in design and implementation as well as imprecision of results. AUTHORS' CONCLUSIONS:This review provides low-quality evidence that resistive inspiratory muscle training with a resistive threshold device is moderately effective postintervention for improving predicted maximal inspiratory pressure in people with mild to moderate MS, whereas expiratory muscle training showed no significant effects. The sustainability of the favourable effect of inspiratory muscle training is unclear, as is the impact of the observed effects on quality of life.
10.1002/14651858.CD009424.pub2
Relationship of vocal fold atrophy to swallowing safety and cough function in Parkinson's disease.
Yiu Yin,Curtis James A,Perry Sarah E,Troche Michelle S
The Laryngoscope
OBJECTIVES:When swallowing function is compromised in patients with Parkinson's disease (PD), cough plays a crucial role in clearing the airway and preventing pulmonary complications. The aim of this study was to determine the influence of vocal fold atrophy severity as measured by the bowing index (BI) on airway protection in PD. METHODS:Thirty participants with PD completed measures of voluntary and reflex cough. Flexible laryngoscopy with endoscopic evaluation of swallowing allowed for measurement of BI using ImageJ software. Swallowing safety was scored on the Penetration-Aspiration Scale (PAS). Regression and receiver operating characteristic (ROC) analyses were performed to test our study aim. RESULTS:Twenty-four of 30 participants had some degree of vocal fold atrophy (BI >0). When controlling for age, disease duration did not significantly influence BI. BI was not predictive of any sensorimotor parameters of cough including measures of cough airflow, reflex cough threshold, or urge to cough. BI discriminated participants with near-normal (PAS 1-3) swallowing safety from participants with impaired (PAS 4-8) swallowing safety (P = .01, sensitivity: 87.0%, specificity: 71.4%, cutoff value BI >4.6). CONCLUSION:Vocal fold atrophy is a potential factor contributing to poor swallowing safety in PD. BI was not associated with cough function in this PD cohort, contrary to prior studies that have shown improved cough measures after vocal fold augmentation. Vocal fold atrophy in PD remains an important area of study as a targetable intervention for patients with airway protective dysfunction. Future studies should include measures of glottic closure during vocal fold adduction. LEVEL OF EVIDENCE:Level 3 Laryngoscope, 130:303-308, 2020.
10.1002/lary.28158
Development of an Italian version of the Leicester cough questionnaire and its relationship with other symptom-specific measures for patients with chronic cough.
Respiratory medicine
OBJECTIVE:To implement subjective methods for measuring the impact of chronic cough on patients' daily life, including an Italian version of the symptom-specific, health status measure for patients with chronic cough, i.e. the Leicester Cough Questionnaire (LCQ). METHODS:Sixty-five chronic cough patients attended a tertiary cough clinic on two separate occasions 8 weeks apart. The visual analogue scale for cough severity (VAS), the LCQ and the cough disturbance score (CDS) were administered on both occasions. The LCQ was adapted for Italian conditions following a forward-backward translation procedure. Concurrent validation, internal consistency, repeatability and responsiveness were determined. RESULTS:The CDS, VAS and LCQ were correlated (r coefficients ranging from 0.69 to 0.94, p < 0.01). The internal consistency for each LCQ domain was high (alpha coefficient range 0.87-0.93), as was the 8-week repeatability of the LCQ in the patients (n = 36, 60 %) who displayed no change in CDS and VAS (intra-class correlation coefficient = 0.86, p < 001) over the same period. Patients who reported an improvement in CDS and VAS after 8 weeks (n = 29) also demonstrated significant improvements in each LCQ domain. The mean difference in LCQ total score before and after improvements was 2.26 (95 % CI: 1.58-4.47). CONCLUSIONS:The Italian version of the LCQ appears to be just as valid as the other language versions of the questionnaire. In addition, the CDS appears to be a clinically useful, symptom-specific measure of the overall disturbance provoked by cough.
10.1016/j.rmed.2024.107642
The Efficacy of Superior Laryngeal Nerve Block for Neurogenic Cough: A Placebo-Controlled Trial.
The Laryngoscope
OBJECTIVES:Chronic cough is a common and debilitating problem. The objective of this study is to assess the efficacy and safety of superior laryngeal nerve (SLN) block for neurogenic cough through a placebo-controlled, prospective trial. METHODS:Patients were recruited in an outpatient tertiary care center. Inclusion criteria included a history consistent with neurogenic cough and age ≥ 18. Exclusion criteria included patients with untreated other etiologies of chronic cough (i.e., uncontrolled reflux) and current neuromodulating medication use. Patients were randomized into the treatment (1-2 mL of a 1:1 triamcinolone 40 mg: 1% lidocaine with 1:200,000 epinephrines) or placebo (saline) group and received two unilateral injections at approximately 2-week intervals. Outcomes were measured primarily by the Leicester Cough Questionnaire (LCQ) and a patient symptom log including a visual analog scale of cough severity. RESULTS:17 patients completed the study, including 10 in the treatment group and seven in the placebo group. Eight (80%) patients in the treatment group reported improvement with at least one of the injections, whereas only 1 (14.3%) patient reported improvement in the placebo group (p < 0.0001). Average total LCQ scores increased in the treatment group from 10.09 to 13.15 (p = 0.03), with the most change occurring in the social domain. There was no statistically significant change in LCQ scores for the placebo group. There were no serious adverse events. CONCLUSION:An SLN block is a safe and efficacious procedure for the treatment of neurogenic cough. Further studies are needed to optimize treatment protocol and assess long-term follow-up of patient outcomes. LEVEL OF EVIDENCE:2 Laryngoscope, 133:3068-3074, 2023.
10.1002/lary.30739
Change in Psychological, Physiological, and Situational Factors in Adults After Treatment of Chronic Cough.
French Cynthia L,Crawford Sybil L,Bova Carol,Irwin Richard S
Chest
BACKGROUND:We hypothesized that addressing anxiety and depressive mood disorders will improve chronic cough severity and cough quality of life (CQOL). METHODS:Major tenets of the theory of unpleasant symptoms were examined in a longitudinal observational study of consecutive adults with cough of > 8 weeks' duration treated in our cough clinic. At baseline and 3 and 6 months, subjects completed 3 Punum Ladders rating cough severity, the CQOL Questionnaire, the Depression, Anxiety, and Stress Scales-21, and the Duke Functional Social Support Questionnaire. Cross-sectional baseline and longitudinal regression analyses were conducted. RESULTS:Eighty subjects (55 women) with a mean age of 58.5 ± 11.1 years and a cough duration of 86.0 ± 123.7 months were enrolled. At baseline, worse cough severity was significantly associated with less education and worse ability to speak bothered by cough and the urge to cough. Worse CQOL was significantly associated with worse depression symptoms, urinary incontinence, and ability to speak; use of self-prescribed remedies; and younger age. Significant improvements in depression and stress symptoms occurred at 3 and 6 months. Anxiety symptoms improved, particularly in the first 3 months. Improvement in cough severity was significantly associated with less education, male sex, and improvement in ability to speak and urge to cough. Improvement in CQOL was significantly associated with improvement in urinary incontinence, urge to cough, anxiety symptoms, and use of self-prescribed remedies. CONCLUSIONS:Using the theory of unpleasant symptoms, we have come to appreciate that managing psychological, physiological, and situational factors in addition to focusing on identifying the cause of cough is important to maximize improvement in CQOL.
10.1016/j.chest.2017.06.024
[Simplification and Validation of Leicester Cough Questionnaire in Mandarin-Chinese].
Lin Rongjia,Che Guowei,Xu Zhihua,Wang Mingming,Zhou Kun,Li Pengfei
Zhongguo fei ai za zhi = Chinese journal of lung cancer
BACKGROUND:Patients often have cough after lung surgery, and there is a lack of tools to specifically assess postoperative coughs. LCQ-MC (Leicester Cough Questionnaire in Mandarin-Chinese) was revised and validated to explore its value on clinical application. METHODS:A total of 250 patients undergone the lung operation of single medical team, from September 2015 to December 2016 in the Department ofThoracic Surgery, West China Hospital, Sichuan University, were investigated. Among them, 121 patients completed LCQ-MC and 129 patients completed simplified LCQ-MC, we verified the reliability and validity. RESULTS:The new questionnaire was not changed in terms of content layout and the scoring method of LCQ-MC, consisting of 12 items and three domains (physical, psychological and social). There was good content validity (S-CVI/UA=0.83). Concurrent validity was high when the simplified LCQ-MC was compared with daytime cough symptom score (r=-0.578, P<0.001). There was a moderate relationship with response to night-time cough symptom score (r=-0.358, P=-0.004) and SF36 total score (r=0.346, P=0.030), and weak relationship with the Hospital Anxiety and Depression Scale total score (r=-0.241, P=0.046). Cronbach's alpha coefficients of simplified LCQ-CM total and three domains varied between 0.79 and 0.89. One week apart test-retest reliability (n=30) was high (r=0.88-0.96). CONCLUSIONS:Simplified LCQ-MC has good reliability and validity that can be used for clinical applications.
10.3779/j.issn.1009-3419.2017.07.05
The demographic and clinical characteristics of an Italian population of adult outpatients with chronic cough.
Campi Giacomo,Noale Marianna,Fabbrizzi Alessio,Lavorini Federico,Maggi Stefania,Fontana Giovanni
Aging clinical and experimental research
BACKGROUND:Chronic cough is a major health problem worldwide and patients are best managed in specialised tertiary centres. Little information is available on the characteristics of chronic cough patients in several European countries, including Italy. AIMS:We report on the demographic, anthropometric and clinical features of a large Italian population of adult chronic cough outpatients (about 1200), who were referred to a specialised clinic in Florence, Italy, from 2008 to 2018. METHODS:Demographic, environmental, lifestyle and clinical information was collected at enrolment by means of a custom-designed electronic questionnaire that only allowed for uniform responses. A subjective measure of cough-related discomfort (cough score) was also obtained using a modified Borg Scale. A multivariable logistic regression model was defined to identify the patients' characteristics associated with the cough score. RESULTS:The characteristics of the examined population (n = 1204 outpatients) were strikingly similar to those described elsewhere. Female patients outnumbered the males [n = 847 females, (70.0%)]; both females and males displayed the same average cough score. The median age of outpatients was 61 (quartile 1 = 48; quartile 3 = 70) years; age and cough duration were unrelated to the cough score. Nasal obstruction, coughing during consultation, coughing during meals, throat clearing and the presence of respiratory abnormalities were correlated with the degree of discomfort caused by coughing. DISCUSSION:The features of chronic cough patients are similar worldwide. The process of cough reflex hypersensitisation may soothe sex-related perceptual differences, leading to similar levels of discomfort. CONCLUSIONS:There seem to be clinical indicators that help in assessing the level of cough-related discomfort.
10.1007/s40520-019-01464-4
Clinical assessment of chronic cough severity.
Raj Anita A,Birring Surinder S
Pulmonary pharmacology & therapeutics
The assessment of cough severity solely through consultation with the patient is limited by its subjective nature and variability of physician judgement. The assessment of cough has been hampered by a paucity of objective tools, those available have been poorly validated, non-standardized and are impractical for clinical use. Recent developments have overcome some of these problems and a variety of tools can now be used to assess cough that include visual analogue scales (VAS), quality-of-life questionnaires, cough reflex sensitivity measurement and automated cough frequency monitors. These tools can be used to validate the presence of cough and assess response to therapy. They will also have an important role in clinical trials.
10.1016/j.pupt.2006.10.002
Speech and language therapy for management of chronic cough.
The Cochrane database of systematic reviews
BACKGROUND:Cough both protects and clears the airway. Cough has three phases: breathing in (inspiration), closure of the glottis, and a forced expiratory effort. Chronic cough has a negative, far-reaching impact on quality of life. Few effective medical treatments for individuals with unexplained (idiopathic/refractory) chronic cough (UCC) are known. For this group, current guidelines advocate the use of gabapentin. Speech and language therapy (SLT) has been considered as a non-pharmacological option for managing UCC without the risks and side effects associated with pharmacological agents, and this review considers the evidence from randomised controlled trials (RCTs) evaluating the effectiveness of SLT in this context. OBJECTIVES:To evaluate the effectiveness of speech and language therapy for treatment of people with unexplained (idiopathic/refractory) chronic cough. SEARCH METHODS:We searched the Cochrane Airways Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, trials registries, and reference lists of included studies. Our most recent search was 8 February 2019. SELECTION CRITERIA:We included RCTs in which participants had a diagnosis of UCC having undergone a full diagnostic workup to exclude an underlying cause, as per published guidelines or local protocols, and where the intervention included speech and language therapy techniques for UCC. DATA COLLECTION AND ANALYSIS:Two review authors independently screened the titles and abstracts of 94 records. Two clinical trials, represented in 10 study reports, met our predefined inclusion criteria. Two review authors independently assessed risk of bias for each study and extracted outcome data. We analysed dichotomous data as odds ratios (ORs), and continuous data as mean differences (MDs) or geometric mean differences. We used standard methods recommended by Cochrane. Our primary outcomes were health-related quality of life (HRQoL) and serious adverse events (SAEs). MAIN RESULTS:We found two studies involving 162 adults that met our inclusion criteria. Neither of the two studies included children. The duration of treatment and length of sessions varied between studies from four sessions delivered weekly, to four sessions over two months. Similarly, length of sessions varied slightly from one 60-minute session and three 45-minute sessions to four 30-minute sessions. The control interventions were healthy lifestyle advice in both studies.One study contributed HRQoL data, using the Leicester Cough Questionnaire (LCQ), and we judged the quality of the evidence to be low using the GRADE approach. Data were reported as between-group difference from baseline to four weeks (MD 1.53, 95% confidence interval (CI) 0.21 to 2.85; participants = 71), revealing a statistically significant benefit for people receiving a physiotherapy and speech and language therapy intervention (PSALTI) versus control. However, the difference between PSALTI and control was not observed between week four and three months. The same study provided information on SAEs, and there were no SAEs in either the PSALTI or control arms. Using the GRADE approach we judged the quality of evidence for this outcome to be low.Data were also available for our prespecified secondary outcomes. In each case data were provided by only one study, therefore there were no opportunities for aggregation; we judged the quality of this evidence to be low for each outcome. A significant difference favouring therapy was demonstrated for: objective cough counts (ratio for mean coughs per hour on treatment was 59% (95% CI 37% to 95%) relative to control; participants = 71); symptom score (MD 9.80, 95% CI 4.50 to 15.10; participants = 87); and clinical improvement as defined by trialists (OR 48.13, 95% CI 13.53 to 171.25; participants = 87). There was no significant difference between therapy and control regarding subjective measures of cough (MD on visual analogue scale of cough severity: -9.72, 95% CI -20.80 to 1.36; participants = 71) and cough reflex sensitivity (capsaicin concentration to induce five coughs: 1.11 (95% CI 0.80 to 1.54; participants = 49) times higher on treatment than on control). One study reported data on adverse events, and there were no adverse events reported in either the therapy or control arms of the study. AUTHORS' CONCLUSIONS:The paucity of data in this review highlights the need for more controlled trial data examining the efficacy of SLT interventions in the management of UCC. Although a large number of studies were found in the initial search as per protocol, we could include only two studies in the review. In addition, this review highlights that endpoints vary between published studies.The improvements in HRQoL (LCQ) and reduction in 24-hour cough frequency seen with the PSALTI intervention were statistically significant but short-lived, with the between-group difference lasting up to four weeks only. Further studies are required to replicate these findings and to investigate the effects of SLT interventions over time. It is clear that SLT interventions vary between studies. Further research is needed to understand which aspects of SLT interventions are most effective in reducing cough (both objective cough frequency and subjective measures of cough) and improving HRQoL. We consider these endpoints to be clinically important. It is also important for future studies to report information on adverse events.Because of the paucity of data, we can draw no robust conclusions regarding the efficacy of SLT interventions for improving outcomes in unexplained chronic cough. Our review identifies the need for further high-quality research, with comparable endpoints to inform robust conclusions.
10.1002/14651858.CD013067.pub2
Validity and reliability of the Swedish version of the Leicester Cough Questionnaire in unexplained chronic cough.
Respiratory medicine
BACKGROUND:Cough is considered chronic when it lasts for >8 weeks. When no medical explanation can be found it is often called unexplained chronic cough (UCC), which may affect health-related quality of life (HRQOL). This study aimed to assesses the validity and reliability of the Swedish version of the Leicester Cough Questionnaire (LCQ-S) in patients with UCC. METHODS:Seventy-six consecutively selected patients with UCC replied to: a local questionnaire; the LCQ-S; a Visual Analog Scale (VAS) for cough; the Swedish version of the Hull Airway Reflux Questionnaire (HARQ-S); and the Chemical Sensitivity Scale for Sensory Hyperreactivity (CSS-SHR). To evaluate the reproducibility of the LCQ-S, the VAS and LCQ-S were answered again after two to four weeks. RESULTS:Seventy-four patients (17 men) answered the questionnaires at baseline. Concurrent validity for LCQ-S was regarded as moderate with the VAS for cough and HARQ-S. Internal consistency using Cronbach's alpha was high for the LCQ-S total score (0.92) and satisfactory for the LCQ-S domains (0.78-0.83). Reliability and reproducibility were analysed in 57 patients (14 men). Intra-class correlation for the LCQ-S total score and domains showed strong reliability (≥0.92), without any significant differences over time. The standard error of measurement and the smallest real difference were 1.26 and 3.49, respectively. The Bland-Altman plot showed no systematic change in the mean values. CONCLUSIONS:The LCQ-S has good validity and reliability and can be used in clinical settings to evaluate HRQOL in Swedish-speaking adult patients with UCC.
10.1016/j.rmed.2024.107582
Evaluating cough assessment tools: a systematic review.
Schmit Kristine M,Coeytaux Remy R,Goode Adam P,McCrory Douglas C,Yancy William S,Kemper Alex R,Hasselblad Vic,Heidenfelder Brooke L,Sanders Gillian D
Chest
BACKGROUND:Little is known about the comparative validity, reliability, or responsiveness of instruments for assessing cough frequency or impact, where the term impact encompasses both cough severity and the impact of cough on health-related quality of life. METHODS:We conducted a systematic review to evaluate instruments that assess cough frequency or impact in adults, adolescents, and children with acute or chronic cough. RESULTS:Seventy-eight studies were included, of which eight were randomized controlled trials and 70 were observational studies. In all age groups, audio and video electronic recording devices had good reliability compared with other methods of assessing cough frequency but had variable correlation with other cough assessments, such as visual analog scale scores, quality-of-life questionnaires, cough diaries, and tussigenic challenges. Among adult and adolescent patients, the Leicester Cough Questionnaire (LCQ) and the Cough-Specific Quality-of-Life Questionnaire (CQLQ) were valid and reliable, showing high intraclass and test-retest correlations. Among children, the Parent Cough-Specific Quality of Life Questionnaire and Pediatric Cough Questionnaire were valid and reliable. CONCLUSIONS:Electronic recording devices can be valid assessments of cough frequency. The LCQ and CQLQ for adults and the Parent Cough-Specific Quality of Life questionnaire for children are valid instruments for assessing cough impact. There is limited but insufficient evidence to determine the reliability or concurrent validity of the different types of cough diaries or visual analog scale scores. There are also limited data to support the responsiveness of recording devices. There is good responsiveness data for the LCQ and CQLQ, but more evidence is needed.
10.1378/chest.13-0310
[Epidemiology of chronic cough in China: current status and future perspective].
Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases
Chronic cough is one of the most common major complaints in medical outpatient. Chronic cough not only seriously affects quality of personal life, but also burdens public health. Large-scale and high-quality epidemiological study on chronic cough has not been carried out in China, and relevant reviews are also lacking. Therefore, based on the studies concerning epidemiology of chronic cough in China, we reviewed the prevalence, risk factors, etiology, quality of life and economic burden. In addition, future perspectives and reasonable suggestions for the development of epidemiology of chronic cough were also proposed.
10.3760/cma.j.cn112147-20211104-00773
Screening for silent aspiration in hyperacute stroke: A feasibility study of clinical swallowing examination and cough reflex testing.
International journal of language & communication disorders
BACKGROUND:Silent aspiration (SA) is common post-stroke and associated with increased risk of pneumonia, length of stay and healthcare costs. Clinical swallow examinations (CSEs) are unreliable measures of SA. There is no consensus on the clinical components that best detect SA. Cough reflex testing (CRT) is an alternative/adjunct whose SA detection accuracy also lacks consensus. AIMS:To investigate the feasibility of CSE versus CRT against gold standard flexible endoscopic evaluation of swallowing (FEES) for SA identification and to estimate its prevalence in a hyperacute stroke setting. METHODS & PROCEDURES:A single-arm preliminary, prospective, feasibility study of patients less than 72 h post-stroke, over a 31-day period on a hyperacute stroke unit: the Royal Victoria Infirmary, Newcastle-upon-Tyne, UK. Ethical approval for the study was obtained. The study tested the feasibility and acceptability of introducing CRT and developing a standardized CSE. Consent/assent was obtained for all participants. Patients unfit for study were excluded. OUTCOMES & RESULTS:A total of 62% of patients less than 72 h post-stroke (n = 61) were eligible. A total of 75% of those approached (n = 30) consented. A total of 23 patients completed all tests. The principal barrier was anxiety regarding FEES. Mean test time for CRT = 6 min; CSE = 8 min; FEES = 17 min. Patients rated CRT and FEES on average as moderately uncomfortable. A total of 30% (n = 7) of participants who received FEES presented with SA. CONCLUSIONS & IMPLICATIONS:CRT, CSE and FEES are feasible in 58% of hyperacute stroke patients in this setting. FEES anxiety is the main recruitment barrier and is not always well tolerated. Results support further work to establish optimum methods and differential sensitivity/specificity of CRT and CSE in hyperacute stroke for SA identification. WHAT THIS PAPER ADDS:What is already known on this subject SA significantly increases the risk of pneumonia in the early days post-stroke. CSEs are unreliable for identification of SA risk in this population. CRT is gaining popularity as a potential tool to identify stroke patients at risk of SA, though there are questions regarding the efficacy of the clinical protocol currently being used in the UK. What this study adds to existing knowledge This study demonstrates that it is practical and feasible to carry out a larger scale study in this setting to compare CSE and CRT including a consideration of an approach combining both methods for clinical identification of SA versus FEES. Preliminary findings suggest that CSE may have higher levels of sensitivity than CRT for SA identification. What are the potential or actual clinical implications of this work? The results of this study suggest that further work is needed to establish the optimum methods and differential sensitivity/specificity of clinical tools for SA detection in hyperacute stroke.
10.1111/1460-6984.12893
Assessment and management of cough among patients with lung cancer in a radiotherapy department in China: a best practice implementation project.
Zhang Lanfang,Wu Yanni,Du Mengya,He Lian,Xie Guozhu,Wang Hongmei,Zhou Chunlan,Chen Peijuan
JBI database of systematic reviews and implementation reports
OBJECTIVES:This project aimed to implement an evidence-based practice to assess and manage lung cancer-associated cough, thereby relieving patients' physical pain and psychological challenges and improving their quality of life. INTRODUCTION:Cough is one of the most common symptoms experienced by patients with lung cancer. If a cough is not proactively managed, patients may develop decreased compliance with treatments and experience a reduced quality of life. Cough assessment and management are essential components of nursing practice that should include evidence-based interventions. METHODS:Seven evidence-based audit criteria were developed from current evidence. The JBI Practical Application of Clinical Evidence System (PACES) was used to perform a baseline audit on 30 patients and 20 nurses in the Department of Radiotherapy of Nanfang Hospital. The Getting Research into Practice (GRiP) component of PACES was used to identify barriers, strategies, resources and outcomes. Following implementation of strategies to improve compliance, a post-audit was conducted using the same sample size and audit criteria. RESULTS:The seven evidence-based audit criteria were as follows: 1) Clinicians have received training on the assessment and management of lung cancer-associated cough; 2) In patients with lung cancer-associated cough, a comprehensive assessment was conducted to identify any co-existing causes linked to cough; 3) Any reversible causes of cough were treated according to evidence-based guidelines; 4) A validated scale was used to assess the frequency and severity of cough and distress experienced by the patients; 5) Patients (and their caregivers) have received education regarding management of cough; 6) Patients (and their caregivers) have received training on cough suppression exercises; 7) For symptomatic therapy, a stepwise approach was followed according to evidence-based guidelines. The baseline results showed that compliance rates were 0% for criteria 1, 4 and 5; 70% for criterion 6; 80% for criterion 7; 90% for criterion 3 and 93% for criterion 2. The implementation of strategies to increase compliance with best practice, including establishing training and education programs for nursing staff and patients, utilizing some validated scales to assess the frequency and severity of cough and the distress caused to the patients, and establishing a quality control team to supervise implementation of the assessment and management of cough, achieved ≥ 93% compliance rate for all seven audit criteria. CONCLUSION:An evidence-based and nurses-oriented best practice for cough assessment and management was successfully established among patients with lung cancer-associated cough.
10.11124/JBISRIR-2017-004001
Quantifying test-retest variability of natural and suppressed citric acid cough thresholds and urge to cough ratings.
Wallace Emma,Guiu Hernandez Esther,Ang Alicia,Macrae Phoebe
Pulmonary pharmacology & therapeutics
INTRODUCTION:The citric acid cough reflex test (CRT) is used to quantify cough sensitivity and evaluate the effects of cough therapies and antitussive medications. This study quantifies the test-retest variability of natural and suppressed citric acid cough thresholds and urge to cough ratings in healthy individuals. METHODS:Healthy adults (n = 16) inhaled increasing concentrations of citric acid (0.01-3.2 mol/L) on three alternate days (1, 3, 5) until C cough thresholds (i.e. two consecutive coughs within 3 s) or the highest concentrations of citric acid was reached. Participants were instructed to "cough if you need to" in the natural cough condition, and "try not to cough" in the suppressed cough condition. Following each inhalation, participants were asked to rate their urge to cough (UTC) using a modified Borg Scale. RESULTS:Natural cough thresholds (NCTs) increased across days 1-3 (0.87 doubling concentrations, 95% CI, 0.28, 1.44, p = 0.004) and 1-5 (0.87 doubling concentrations, 95% CI, 0.33, 1.41, p = 0.004). Suppressed cough thresholds (SCTs) increased across days 1-5 (0.64 doubling concentrations per day, 95% CI, 0.03, 1.22, p = 0.04). After taking the effect of day into account, NCTs and SCTs varied within-participants by 0.75 (95% CI, 0.53, 0.93) and 0.78 (95% CI, 0.55,0.98) doubling concentrations respectively. UTC ratings at NCT, or SCT did not significantly increase across days 1-3 or 1-5. Sub-threshold (0.05 mol/L) UTC ratings increased across days 1-3 (-1.43 ratings per day, 95% CI, -2.31, -0.5, p = 0.005) and 1-5 (-1.71 ratings per day, 95% CI, -2.59, -0.79, p = 0.001). UTC ratings at NCT, SCT, and sub-threshold varied within-participants after taking into account the effect of day by 1.34 (95% CI, 1.03, 1.71), 1.47 (95% CI, 1.10, 1.91) and 1.20 (95% CI, 0.91, 1.50) ratings. CONCLUSIONS:Natural and suppressed cough thresholds and UTC ratings are subject to test-retest variability. These data are important for the use of citric acid CRT as an outcome measure in longitudinal cough research, as they facilitate interpretation of whether changes in citric acid cough thresholds across days reflect true changes in cough sensitivity, rather than an artefact of repeating the test.
10.1016/j.pupt.2019.101838
Design and characterization of a cough simulator.
Zhang Bo,Zhu Chao,Ji Zhiming,Lin Chao-Hsin
Journal of breath research
Expiratory droplets from human coughing have always been considered as potential carriers of pathogens, responsible for respiratory infectious disease transmission. To study the transmission of disease by human coughing, a transient repeatable cough simulator has been designed and built. Cough droplets are generated by different mechanisms, such as the breaking of mucus, condensation and high-speed atomization from different depths of the respiratory tract. These mechanisms in coughing produce droplets of different sizes, represented by a bimodal distribution of 'fine' and 'coarse' droplets. A cough simulator is hence designed to generate transient sprays with such bimodal characteristics. It consists of a pressurized gas tank, a nebulizer and an ejector, connected in series, which are controlled by computerized solenoid valves. The bimodal droplet size distribution is characterized for the coarse droplets and fine droplets, by fibrous collection and laser diffraction, respectively. The measured size distributions of coarse and fine droplets are reasonably represented by the Rosin-Rammler and log-normal distributions in probability density function, which leads to a bimodal distribution. To assess the hydrodynamic consequences of coughing including droplet vaporization and polydispersion, a Lagrangian model of droplet trajectories is established, with its ambient flow field predetermined from a computational fluid dynamics simulation.
10.1088/1752-7163/aa5cc6
The Intensity of Voluntary, Induced, and Spontaneous Cough.
Lee Kai K,Ward Katie,Rafferty Gerrard F,Moxham John,Birring Surinder S
Chest
BACKGROUND:The intensity of cough is an important determinant of cough severity. Few studies have quantified cough intensity in patients with chronic cough with objective measures. We investigated the intensity of voluntary, induced, and spontaneous cough in patients with chronic cough and healthy control subjects. METHODS:Patients with chronic cough and control subjects underwent physiologic assessment of the intensity of maximum voluntary, capsaicin-induced, and spontaneous cough. Assessments included measurement of gastric pressure (Pga) and esophageal pressure (Pes) during cough, peak cough flow (PCF), expiratory muscle strength (twitch gastric pressure [TwPga]), and cough compression phase duration (CPD). Subjective perception of cough intensity was assessed using a visual analog scale (VAS). RESULTS:Pes, Pga, and PCF during maximum voluntary cough were significantly greater in patients with chronic cough compared with control subjects (P = .003-.042). There was no difference in TwPga between patients and control subjects. CPD was increased in female patients compared with control subjects (mean ± SD, 0.50 ± 0.22 s vs 0.28 ± 0.17 s; P = .007). Mean ± SD Pes during spontaneous cough was comparable to induced cough (128 ± 28 cm H2O vs 122 ± 37 cm H2O, P = .686) but less than maximum voluntary cough (170 ± 46 cm H2O, P = .020). Median within-subject correlation coefficients between cough intensity VAS and Pes, Pga, and PCF were r = 0.82 to 0.86. CONCLUSIONS:Maximum voluntary cough intensity was increased in patients with chronic cough compared with control subjects. There was no significant difference in expiratory muscle contractility. Further studies should evaluate the compressive phase of cough in more detail. Physiologic measures of cough intensity correlated strongly with subjective perception of intensity in patients with chronic cough and may be relevant objective outcome measures for clinical studies.
10.1378/chest.15-0138
Decreased cough sensitivity and aspiration in Parkinson disease.
Troche Michelle S,Brandimore Alexandra E,Okun Michael S,Davenport Paul W,Hegland Karen W
Chest
BACKGROUND:Aspiration pneumonia is a leading cause of death in people with Parkinson disease (PD). The pathogenesis of these infections is largely attributed to the presence of dysphagia with silent aspiration or aspiration without an appropriate cough response. The goal of this study was to test reflex cough thresholds and associated urge-to-cough (UTC) ratings in participants with PD with and without dysphagia. METHODS:Twenty participants with PD were recruited for this study. They completed a capsaicin challenge with three randomized blocks of 0, 50, 100, and 200 μM capsaicin and rated their UTC by modified Borg scale. The concentration of capsaicin that elicited a two-cough response, total number of coughs, and sensitivity of the participant to the cough stimulus (UTC) were measured. The dysphagia severity of participants with PD was identified with the penetration-aspiration scale. RESULTS:Most participants with PD did not have a consistent two-cough response to 200 μM capsaicin. UTC ratings and total number of coughs produced at 200 μM capsaicin were significantly influenced by dysphagia severity but not by general PD severity, age, or disease duration. Increasing levels of dysphagia severity resulted in significantly blunted cough sensitivity (UTC). CONCLUSIONS:UTC ratings may be important in understanding the mechanism underlying morbidity related to aspiration pneumonia in people with PD and dysphagia. Further understanding of decreased UTC in people with PD and dysphagia will be essential for the development of strategies and treatments to address airway protection deficits in this population.
10.1378/chest.14-0066
Relationship between pulmonary, cough, and swallowing functions in individuals with amyotrophic lateral sclerosis.
Muscle & nerve
INTRODUCTION/AIMS:Evaluations of pulmonary, cough, and swallow function are frequently performed to assess disease progression in amyotrophic lateral sclerosis (ALS), yet the relationship between these functions remains unknown. We therefore aimed to determine relationships between these measures in individuals with ALS. METHODS:One hundred individuals with ALS underwent standardized tests: forced vital capacity (FVC), maximum expiratory/inspiratory pressure (MEP, MIP), voluntary cough peak expiratory flow (PEF), and videofluoroscopic swallow evaluation (VF). Duplicate raters completed independent, blinded ratings using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale. Descriptives, Spearman's Rho correlations, Kruskal-Wallis analyses, and Pearson's chi-squared tests were completed. RESULTS:Mean and standard deviation across pulmonary and cough measures were FVC: 74.2% predicted (± 22.6), MEP: 91.6 cmHO (± 46.4), MIP cmHO: 61.1 (± 28.9), voluntary PEF: 352.7 L/min (± 141.6). DIGEST grades included: 0 (normal swallowing): 31%, 1 (mild dysphagia): 48%, 2 (moderate dysphagia): 10%, 3 (severe dysphagia): 10%, and 4 (life-threatening dysphagia): 1%. Positive correlations were observed: MEP-MIP: r = .76, MIP-PEF: r = .68, MEP-PEF: r = .61, MIP-FVC: r = .60, PEF-FVC: r = .49, and MEP-FVC: r = .46, p < .0001. MEP (p = .009) and PEF (p = .04) differed across DIGEST safety grades. Post hoc analyses revealed significant between group differences in MEP and PEF across DIGEST safety grades 0 versus 1 and grades 0 versus 3, (p < .05). DISCUSSION:In this cohort of individuals with ALS, pulmonary function, and voluntary cough were associated. Expiratory metrics (MEP, PEF) were diminished in individuals with unsafe swallowing, increasing their risk for effectively defending the airway.
10.1002/mus.28113
How best to measure cough clinically.
Birring Surinder S,Spinou Arietta
Current opinion in pharmacology
It is possible to measure cough by assessing its severity, frequency, intensity, associated urge and its impact on quality of life. Cough severity can simply be assessed with a Visual Analogue Scale. Cough frequency can be assessed objectively with cough frequency monitors. Validated cough monitors include the Leicester Cough Monitor and the VitaloJAK. Cough reflex sensitivity measurement is better used to investigate the mechanisms of action of antitussive medications, rather than assessing efficacy. Health-Related Quality of Life measures are available to assess the impact of cough; they include the validated Leicester Cough Questionnaire and Cough-specific Quality of Life Questionnaire for adult patients. It is best to assess cough with a combination of subjective and objective tools, to capture its wide-ranging impact.
10.1016/j.coph.2015.03.003
The Manchester cough in lung cancer scale: the development and preliminary validation of a new assessment tool.
Molassiotis Alex,Ellis Jackie,Wagland Richard,Williams Mari Lloyd,Bailey Chris D,Booton Richard,Blackhall Fiona,Yorke Janelle,Smith Jaclyn A
Journal of pain and symptom management
CONTEXT:Cough is a common distressing symptom in lung cancer patients. Its assessment is hampered by the lack of a validated scale to measure the complex cough experience in this population. OBJECTIVES:To describe the development and preliminary validation of a scale to measure cough in lung cancer patients. METHODS:In the first phase, collection of qualitative data from patient interviews, a review of literature, and identification of noncancer cough scales resulted in the development of a pool of 30 items. This item pool was tested for appropriateness of content and breadth of coverage with 18 patients with lung cancer and 25 health care professionals. The second phase was the operationalization/phrasing of items. The final phase was the scale's field testing with 139 patients, 49 of whom repeated the assessment after one week. RESULTS:The first phase led to the deletion of several items and the addition of four, resulting in a final scale for field testing of 21 items. In the field testing, the scale was decreased to 10 items, eliminating items on psychometric grounds. The final scale's Cronbach alpha (internal consistency) was 0.86, item to total correlations ranged from 0.40 to 0.76, and test-retest reliability was high (intraclass correlation=0.83). CONCLUSION:We have developed a promising tool to assess cough in lung cancer, but this needs validation, and future studies should determine whether this is a sensitive and responsive tool. A fully validated tool can be used in the clinical assessment of cough in cancer patients, and as a unidimensional impact scale in the measurement of cough as an outcome in intervention studies.
10.1016/j.jpainsymman.2012.01.015
Structural and Functional Correlates of Higher Cortical Brain Regions in Chronic Refractory Cough.
Chest
BACKGROUND:Chronic refractory cough significantly impairs the psychological and social aspects of quality of life. Loss of inhibitory control is suggested as a potential central neurobiological mechanism underlying chronic refractory cough. RESEARCH QUESTION:Do structural and functional changes related to chronic cough occur in higher cortical brain regions? STUDY DESIGN AND METHODS:The structural and resting-state functional alterations in the brains of 15 patients with chronic refractory cough and 15 age- and sex-matched healthy control participants were evaluated. Gray matter volumes of the whole brain were measured using voxel-based morphometry based on T1-weighted MRI. Intrinsic functional connectivity within large-scale brain networks was examined on resting-state functional MRI. Correlation analyses were performed to examine the relationships of these brain changes with duration, severity, and impact of cough. RESULTS:Compared with healthy control participants, patients with chronic refractory cough demonstrated a lower gray matter volume in the left frontal cluster and enhanced functional connectivity within the left frontoparietal network, which were associated with greater cough scores. Furthermore, enhanced functional connectivity within the left frontoparietal network was associated with a greater psychological and social impact of coughing. Lower left frontal gray matter volume was associated with longer cough duration. INTERPRETATION:Structural and functional alterations in the left frontal brain regions may be implicated in the psychological and social impact and disease duration of chronic refractory cough. Our findings provide new perspectives on developing interventional approaches targeting the cognitive modulation of chronic coughing.
10.1016/j.chest.2022.04.141
Development and validation of the COugh Assessment Test (COAT).
Koo Hyeon-Kyoung,Jeong Ina,Kim Joo-Hee,Kim Sung-Kyoung,Shin Jong-Wook,Park So Young,Rhee Chin Kook,Choi Eun Young,Moon Ji-Yong,Kim Yee Hyung,Lee Hyun,Kang Hye Seon,Min Kyung Hoon,Kim Jin Woo,Kim Je Hyeong,Lee Sang Haak,Yoo Kwang Ha,Kim Deog Kyeom,Yoon Hyoung Kyu,Kim Dong-Gyu,Kim Hui Jung,Jung Ki-Suck,Jang Seung Hun,
Respirology (Carlton, Vic.)
BACKGROUND AND OBJECTIVE:A cough-specific quality-of-life questionnaire is recommended to assess the impact of cough; however, a simple instrument to quantify cough is required for everyday clinical practice. This study was aimed to develop a short patient-completed questionnaire (COugh Assessment Test, COAT). METHODS:The COAT was developed and validated by comparison with the Korean version of Leicester Cough Questionnaire (K-LCQ) and cough numeric rating scale (NRS, 0-10, 11-point scale) for chronic cough patients. RESULTS:Item selection identified five items regarding cough frequency, daily activity, sleep disturbance, fatigue and cough hypersensitivity (0-4 scaling of items, 0-20 score range) through reliability test cohort (n = 78). Test-retest reliability was strong (intra-class correlation coefficient = 0.88). The final COAT was compared with K-LCQ and cough NRS in a validation cohort (n = 323). In Rasch analysis, COAT fitted well to a unidimensional model. Pearson correlations of COAT versus K-LCQ (i) before treatment, (ii) after treatment; COAT versus cough NRS (iii) before treatment, (iv) after treatment; (v) delta-COAT versus delta-cough NRS, (vi) delta-COAT versus delta-K-LCQ were (i) -0.71, (ii) -0.81, (iii) 0.69, (iv) 0.82, (v) -0.66 and (vi) 0.72, respectively. CONCLUSION:The COAT is a useful, simple questionnaire for assessing and monitoring cough.
10.1111/resp.13462
A prospective examination of swallow and cough dysfunction after lung transplantation.
Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society
OBJECTIVES:Swallow and cough dysfunction are possible surgical complications of lung transplantation (LT). We examined voluntary cough strength, sensorimotor reflexive cough integrity, and swallow-related respiratory rate (RR) across swallowing safety and aspiration response groups in recovering LT recipients. METHODS:Forty-five LT recipients underwent flexible endoscopic evaluation of swallowing indexed by the validated Penetration Aspiration Scale. RR before and after a 3-ounce water drinking task was measured. Voluntary and reflexive cough screening were performed to index motor and sensory outcomes. T-tests, one-way ANOVAs, and chi-square (odds ratios) were used. RESULTS:60% of patients exhibited laryngeal penetration (n = 27) and 40% demonstrated tracheal aspiration (n = 18); 72% (n = 13) demonstrated silent aspiration. Baseline RR was higher in aspirators versus non-aspirators (26.5 vs. 22.6, p = 0.04) and in silent aspirators compared to non-silent aspirators (27.9 vs. 20.7, p = 0.01). RR change post-swallowing did not differ between aspiration response groups; however, it was significantly higher in aspirators compared to non-aspirators (3 vs. -2, p = 0.02). Compared to non-silent aspirators, silent aspirators demonstrated reduced voluntary cough peak expiratory flow (PEF; 166 vs. 324 L/min, p = 0.01). PEF, motor and urge to cough reflex cough ratings did not differ between aspirators and non-aspirators. Silent aspirators demonstrated a 7.5 times higher odds of failing reflex cough screening compared to non-silent aspirators (p = 0.07). CONCLUSIONS:During the acute recovery period, all LT participants demonstrated some degree of unsafe swallowing and reduced voluntary cough strength. Silent aspirators exhibited elevated RR, reduced voluntary cough physiologic capacity to defend the airway, and a clinically distinguishable blunted motor response to reflex cough screening.
10.1111/nmo.14458