Cooling Blankets in Hospitalized Patients: Time to Reevaluate.
Chen Thomas,Malhotra Prashant,Khameraj Aradhana,Ong-Bello Nelda,Vyas Pooja P,Rasul Rehana,Schwartz Rebecca M,Farber Bruce F
The American journal of the medical sciences
BACKGROUND:The therapeutic benefits and rationale for treating fevers with external cooling methods remain unclear. We aimed to describe the clinical settings in which cooling blankets (CBs) are used. DESIGN:We conducted a retrospective chart review of CB use in adult patients admitted to our tertiary care center over a one-year period. We measured how they are used and correlations between clinical variables and their duration of use. RESULTS:561 patients were included in our study. The mean highest temperature during hospitalization was 39.35 °C (SD, 0.67). Shivering occurred in 176 patients (31.4%) while on a CB although 303 patients (54%) had no data regarding shivering. Discontinuation of CBs was recorded in only 177 (30.5%) cases. Among these, the median duration of use was 33.37 h (IQR: 18.13-80.38) while the median duration of fever was 22.13 h (IQR 6.67-51.98). Duration of CB use was highly correlated with fever duration (Spearman's rho, 0.771, p < .001), moderately with length of stay (LOS) (rho, 0.425, p < .001), LOS after CB initiation (rho, 0.475, p < .001) and antipyretic use (rho, 0.506, p < .001). No other statistically significant correlations were observed. CONCLUSION:Documentation of CB use including temperature set points, time of discontinuation and duration in EMRs was poor. We could not establish benefits of CB use in this study but observed that almost a third of patients developed adverse effects in the form of shivering. Thus, adverse effects of CB use may outweigh potential benefits. Their use should be reevaluated and institutional protocols developed for their use.
10.1016/j.amjms.2021.06.009
Association of D-dimer and acute kidney injury associated with rhabdomyolysis in patients with exertional heatstroke: an over 10-year intensive care survey.
Wang Conglin,Yu Baojun,Chen Ronglin,Su Lei,Wu Ming,Liu Zhifeng
Renal failure
Patients with rhabdomyolysis (RM) following exertional heatstroke (EHS) are often accompanied by dysfunction of coagulation and acute kidney injury (AKI). The purpose of this study was to investigate the relationship between D-dimer and AKI in patients with RM following EHS. A retrospective study was performed on patients with EHS admitted to the intensive care unit over 10-year. Data including baseline clinical information at admission, vital organ dysfunction, and 90-day mortality were collected. A total of 84 patients were finally included, of whom 41 (48.8%) had AKI. AKI patients had more severe organ injury and higher 90-day mortality (34.1 0.0%, < 0.001) than non-AKI patients. Multivariate logistic analysis showed that D-dimer (OR 1.3, 95% CI 1.1-1.7, = 0.018) was an independent risk factor for AKI with RM following EHS. Curve fitting showed a curve relationship between D-dimer and AKI. Two-piecewise linear regression showed that D-dimer was associated with AKI in all populations (OR 1.3, 95% CI 1.2-1.5, < 0.001) when D-dimer <10.0 mg/L, in RM group (OR 1.3, 95% CI 1.1-1.5, < 0.001) when D-dimer >0.4 mg/L, in the non-RM group (OR 6.4, 95% CI 1.7-23.9, = 0.005) when D-dimer <1.3 mg/L and D-dimer did not increase the incidence of AKI in the non-RM group when D-dimer >1.3 mg/L. AKI is a life-threatening complication of RM following EHS. D-dimer is associated with AKI in critically ill patients with EHS. The relationship between D-dimer and AKI depends on whether RM is present or not.
10.1080/0886022X.2021.2008975
Dehydration and renal failure in older persons during heatwaves-predictable, hard to identify but preventable?
Brennan Michelle,O'Keeffe Shaun T,Mulkerrin Eamon C
Age and ageing
Extremes of temperature are likely to increase in frequency associated with climate change. Older patients are particularly vulnerable to the effects of heat with excess mortality well documented in this population. Age-associated neurohormonal changes particularly affecting the renin angiotensin aldosterone system (RAAS), alterations in thermoregulatory mechanisms, changes in renal function and body composition render older persons vulnerable to dehydration, renal failure, heat stroke and increased mortality. Barriers to diagnosis and recognition of dehydration and renal failure include the absence of reliable clinical signs and cost-effective diagnostic tools. Regularly used medications also impact on physiological responses to excess heat as well as interfering with the recognition and management of dehydration during heat waves. In view of the above, anticipatory measures should be instituted ideally prior to the onset of heat waves to minimise morbidity and mortality for older people during periods of excess heat.
10.1093/ageing/afz080
Feasibility and Safety of Intravascular Temperature Management for Severe Heat Stroke: A Prospective Multicenter Pilot Study.
Yokobori Shoji,Koido Yuichi,Shishido Hajime,Hifumi Toru,Kawakita Kenya,Okazaki Tomoya,Shiraishi Shinichirou,Yamamura Eiji,Kanemura Takashi,Otaguro Takanobu,Matsumoto Gaku,Kuroda Yasuhiro,Miyake Yasufumi,Naoe Yasutaka,Unemoto Kyoko,Kato Hiroshi,Matsuda Kiyoshi,Matsumoto Hisashi,Yokota Hiroyuki
Critical care medicine
OBJECTIVES:Heat stroke is a life-threatening condition with high mortality and morbidity. Although several cooling methods have been reported, the feasibility and safety of treating heat stroke using intravascular temperature management are unclear. This study evaluated the efficacies of conventional treatment with or without intravascular temperature management for severe heat stroke. DESIGN:Prospective multicenter study. SETTING:Critical care and emergency medical centers at 10 tertiary hospitals. PATIENTS:Patients with severe heat stroke hospitalized during two summers. INTERVENTIONS:Conventional cooling with or without intravascular temperature management. MEASUREMENTS AND MAIN RESULTS:Cooling efficacy, Sequential Organ Failure Assessment score, occurrence rate of serious adverse events, and prognosis based on the modified Rankin Scale and Cerebral Performance Category. Patient outcomes were compared between five centers that were prospectively assigned to perform conventional cooling (control group: eight patients) and five centers that were assigned to perform conventional cooling plus intravascular temperature management (intravascular temperature management group: 13 patients), based on equipment availability. Despite their higher initial temperatures, all patients in the intravascular temperature management group reached the target temperature of 37°C within 24 hours, although only 50% of the patients in the control group reached 37°C (p < 0.01). The intravascular temperature management group also had a significant decrease in the Sequential Organ Failure Assessment score during the first 24 hours after admission (4.0 vs 1.5; p = 0.04). Furthermore, the intravascular temperature management group experienced fewer serious adverse events during their hospitalization, compared with the control group. The percentages of favorable outcomes at discharge and 30 days after admission were not statistically significant. CONCLUSIONS:The combination of intravascular temperature management and conventional cooling was safe and feasible for treating severe heat stroke. The results indicate that better temperature management may help prevent organ failure. A large randomized controlled trial is needed to validate our findings.
10.1097/CCM.0000000000003153
Exertional Heat Stroke, Modality Cooling Rate, and Survival Outcomes: A Systematic Review.
Medicina (Kaunas, Lithuania)
The purpose of this systematic review is to synthesize the influence cooling modality has on survival with and without medical complications from exertional heat stroke (EHS) in sport and military populations. All peer-reviewed case reports or series involving EHS patients were searched in the following online databases: PubMed, Scopus, SPORTDiscus, Medline, CINAHL, Academic Search Premier, and the Cochrane Library: Central Registry of Clinical Trials. Cooling methods were subdivided into "adequate" (>0.15 °C/min) versus "insufficient" (<0.15 °C/min) based on previously published literature on EHS cooling rates. : 613 articles were assessed for quality and inclusion in the review. Thirty-two case reports representing 521 EHS patients met the inclusion criteria. Four hundred ninety-eight (498) patients survived EHS (95.58%) and 23 (4.41%) patients succumbed to complications. Fischer's Exact test on 2 × 2 contingency tables and relative risk ratios were calculated to determine if modality cooling rate was associated with patient outcomes. EHS patients that survived who were cooled with an insufficient cooling rate had a 4.57 times risk of medical complications compared to patients who were treated by adequate cooling methods, regardless of setting (RR = 4.57 (95%CI: 3.42, 6.28)). This is the largest EHS dataset yet compiled that analyzes the influence of cooling rate on patient outcomes. Zero patients died (0/521, 0.00%) when treatment included a modality with an adequate cooling rate. Conversely, 23 patients died (23/521, 4.41%) with insufficient cooling. One hundred seventeen patients (117/521, 22.46%) survived with medical complications when treatment involved an insufficient cooling rate, whereas, only four patients had complications (4/521, 0.77%) despite adequate cooling. Cooling rates >0.15 °C/min for EHS patients were significantly associated with surviving EHS without medical complications. In order to provide the best standard of care for EHS patients, an aggressive cooling rate >0.15 °C/min can maximize survival without medical complications after exercise-induced hyperthermia.
10.3390/medicina56110589
Classic and exertional heatstroke.
Nature reviews. Disease primers
In the past two decades, record-breaking heatwaves have caused an increasing number of heat-related deaths, including heatstroke, globally. Heatstroke is a heat illness characterized by the rapid rise of core body temperature above 40 °C and central nervous system dysfunction. It is categorized as classic when it results from passive exposure to extreme environmental heat and as exertional when it develops during strenuous exercise. Classic heatstroke occurs in epidemic form and contributes to 9-37% of heat-related fatalities during heatwaves. Exertional heatstroke sporadically affects predominantly young and healthy individuals. Under intensive care, mortality reaches 26.5% and 63.2% in exertional and classic heatstroke, respectively. Pathological studies disclose endothelial cell injury, inflammation, widespread thrombosis and bleeding in most organs. Survivors of heatstroke may experience long-term neurological and cardiovascular complications with a persistent risk of death. No specific therapy other than rapid cooling is available. Physiological and morphological factors contribute to the susceptibility to heatstroke. Future research should identify genetic factors that further describe individual heat illness risk and form the basis of precision-based public health response. Prioritizing research towards fundamental mechanism and diagnostic biomarker discovery is crucial for the design of specific management approaches.
10.1038/s41572-021-00334-6
[Advances in pre-hospital recognition and cooling treatment of exertional heat stroke].
Wang Hongping,Chen Wei,Li Shuping,Wang Zhilu,Wu Yutian,Li Hailing
Zhonghua wei zhong bing ji jiu yi xue
OBJECTIVE:Heat stroke (HS) is a life-threatening illness characterized by an altered level of consciousness with an elevated core body temperature 40 centigrade, which may be further classified as exertional heat stroke (EHS) or classical heat stroke (CHS) according to the etiology of the condition. In recent years, the morbidity of EHS increases year by year. The severity and clinical outcome for an EHS casualty have a strong correlation with the area under the time and temperature curve for heat exposure. The early recognition and rapid cooling body core temperature ≤ 38.9 centigrade within 30 minutes of EHS results in the best clinical outcome and minimize severe multiple organ dysfunction and death for patients. Cold water immersion (CWI) is considered as an optimum cooling method for the reversal of hyperthermia in EHS. Some alternative modalities have also shown acceptable cooling rate, for example, the subjects immersed in a circulated water bath controlled below 20 centigrade, tarp-assisted cooling with oscillation, body cooling unit, undressed, air-conditioned room, the whole body and large vessels placed ice packs, massaging the extremities; cold intravenous saline applied to dehydrated one. It is necessary to monitor body core temperature for hypothermia and/or recurrent hyperthermia, and to provide physical care for shivering, agitation, or concerns with the potential discomfort combativeness that may occur during cooling process. In this paper, pre-hospital recognition, care, monitoring and rapid cooling treatment measures of EHS have been reviewed to provide references for early identification of EHS and scientific, reasonable and effective cooling treatment.
10.3760/cma.j.issn.2095-4352.2018.010.021
Can Temperate-Water Immersion Effectively Reduce Rectal Temperature in Exertional Heat Stroke? A Critically Appraised Topic.
Truxton Tyler T,Miller Kevin C
Journal of sport rehabilitation
Clinical Scenario: Exertional heat stroke (EHS) is a medical emergency which, if left untreated, can result in death. The standard of care for EHS patients includes confirmation of hyperthermia via rectal temperature (T) and then immediate cold-water immersion (CWI). While CWI is the fastest way to reduce T, it may be difficult to lower and maintain water bath temperature in the recommended ranges (1.7°C-15°C [35°F-59°F]) because of limited access to ice and/or the bath being exposed to high ambient temperatures for long periods of time. Determining if T cooling rates are acceptable (ie, >0.08°C/min) when significantly hyperthermic humans are immersed in temperate water (ie, ≥20°C [68°F]) has applications for how EHS patients are treated in the field. CLINICAL QUESTION:Are T cooling rates acceptable (≥0.08°C/min) when significantly hyperthermic humans are immersed in temperate water? SUMMARY OF FINDINGS:T cooling rates of hyperthermic humans immersed in temperate water (≥20°C [68°F]) ranged from 0.06°C/min to 0.19°C/min. The average T cooling rate for all examined studies was 0.11±0.06°C/min. Clinical Bottom Line: Temperature water immersion (TWI) provides acceptable (ie, >0.08°C/min) T cooling rates for hyperthermic humans post-exercise. However, CWI cooling rates are higher and should be used if feasible (eg, access to ice, shaded treatment areas). Strength of Recommendation: The majority of evidence (eg, Level 2 studies with PEDro scores ≥5) suggests TWI provides acceptable, though not ideal, T cooling. If possible, CWI should be used instead of TWI in EHS scenarios.
10.1123/jsr.2015-0200
[Protective effect of mild hypothermia at different starting times on organ function in patient with exertional heat stroke].
Li Qinghua,Sun Rongqing,Lyu Hongdi,Shen Dexin,Hu Qing,Wang Haiwei,Wang Nannan,Yan Jin,Wang Jing
Zhonghua wei zhong bing ji jiu yi xue
OBJECTIVE:To investigate the protective effect of mild hypothermia at different starting times on the physiological functions of the viscera of exertional heat stroke (EHS). METHODS:A prospective randomized controlled trial was conducted. EHS patients admitted to intensive care unit of the 159th Hospital of People's Liberation Army and the First Affiliated Hospital of Zhengzhou University from June 2015 to June 2017 were enrolled. The patients were divided into 2, 4, 6 hours start hypothermia treatment groups according to the random number table method, the mild hypothermia was initiated at 2, 4 and 6 hours after the disease onset respectively, and the methods were the same in each group. After treatment of 2, 12, 24 hours, the venous blood in the three groups was collected to detect serum cardiac troponin I (cTnI) with chemiluminescence method, MB isoenzyme of creatine kinase (CK-MB) with immunosuppressive method, creatinine (Cr) with creatine oxidase method, β-microglobulin (β-MG) with turbidimetry, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) with enzyme method. Multiple organ dysfunction syndrome (MODS) within 24 hours after treatment was recorded. Linear regression analysis of the correlation between mild hypothermia start-up time and MODS was done. RESULTS:Ninety-three cases of EHS were included, with 32, 31 and 30 patients in 2, 4, 6 hours start treatment groups respectively. There were no significant differences in gender, age, core temperature, onset time to admission, Glasgow coma scale (GCS), acute physiology and chronic health evaluation system II (APACHE II) score at admission among the three groups. There were no significant differences in the levels of serum cTnI, CK-MB, Cr, β-MG, ALT and AST at 2 hours after treatment. But with the prolongation of the treatment time, all indicators gradually increased. And the earlier start of the mild hypothermia, the less significant of the above indexes. All indexes in 2 hours start treatment group were significantly lower than those of 2 hours and 6 hours start treatment groups at 24 hours after treatment [cTnI (ng/L): 49.53±9.25 vs. 56.52±10.05, 64.57±11.21; CK-MB (U/L): 51.47±11.83 vs. 57.87±7.43, 64.40±7.93; Cr (μmol/L): 140.97±11.33 vs. 148.16±10.39,155.57±8.65; β-MG (mg/L): 10.28±1.46 vs. 11.58±2.13, 12.93±1.98; ALT (U/L): 248.53±75.47 vs. 341.42±129.58, 425.77±101.23; AST (U/L): 197.25±42.59 vs. 292.81±58.49, 351.20±60.41, all P < 0.05]. There was significant difference in the incidence of MODS in 2, 4, 6 hours start treatment groups [43.75% (14/32), 64.52% (20/31), 80.08% (24/30), χ = 8.761, P = 0.013]. Linear regression analysis showed that the earlier onset time of mild hypothermia, the lower incidence of MODS (R = 0.915, P = 0.013). CONCLUSIONS:The application of mild hypothermia in 2 hours can effectively protect the physiological function of EHS organs and reduce the incidence of MODS.
10.3760/cma.j.issn.2095-4352.2018.04.016
Chemically Activated Cooling Vest's Effect on Cooling Rate Following Exercise-Induced Hyperthermia: A Randomized Counter-Balanced Crossover Study.
Hosokawa Yuri,Belval Luke N,Adams William M,Vandermark Lesley W,Casa Douglas J
Medicina (Kaunas, Lithuania)
Exertional heat stroke (EHS) is a potentially lethal, hyperthermic condition that warrants immediate cooling to optimize the patient outcome. The study aimed to examine if a portable cooling vest meets the established cooling criteria (0.15 °C·min or greater) for EHS treatment. It was hypothesized that a cooling vest will not meet the established cooling criteria for EHS treatment. Fourteen recreationally active participants (mean ± SD; male, = 8; age, 25 ± 4 years; body mass, 86.7 ± 10.5 kg; body fat, 16.5 ± 5.2%; body surface area, 2.06 ± 0.15 m. female, = 6; 22 ± 2 years; 61.3 ± 6.7 kg; 22.8 ± 4.4%; 1.66 ± 0.11 m) exercised on a motorized treadmill in a hot climatic chamber (ambient temperature 39.8 ± 1.9 °C, relative humidity 37.4 ± 6.9%) until they reached rectal temperature (T) >39 °C (mean T, 39.59 ± 0.38 °C). Following exercise, participants were cooled using either a cooling vest (VEST) or passive rest (PASS) in the climatic chamber until T reached 38.25 °C. Trials were assigned using randomized, counter-balanced crossover design. There was a main effect of cooling modality type on cooling rates (F[1, 24] = 10.46, < 0.01, η = 0.30), with a greater cooling rate observed in VEST (0.06 ± 0.02 °C·min) than PASS (0.04 ± 0.01 °C·min) (MD = 0.02, 95% CI = [0.01, 0.03]). There were also main effects of sex (F[1, 24] = 5.97, = 0.02, η = 0.20) and cooling modality type (F[1, 24] = 4.38, = 0.047, η = 0.15) on cooling duration, with a faster cooling time in female (26.9 min) than male participants (42.2 min) (MD = 15.3 min, 95% CI = [2.4, 28.2]) and faster cooling duration in VEST than PASS (MD = 13.1 min, 95% CI = [0.2, 26.0]). An increased body mass was associated with a decreased cooling rate in PASS (r = -0.580, = 0.03); however, this association was not significant in vest (r = -0.252, = 0.39). Although VEST exhibited a greater cooling capacity than PASS, VEST was far below an acceptable cooling rate for EHS treatment. VEST should not replace immediate whole-body cold-water immersion when EHS is suspected.
10.3390/medicina56100539
First aid cooling techniques for heat stroke and exertional hyperthermia: A systematic review and meta-analysis.
Douma Matthew J,Aves Theresa,Allan Katherine S,Bendall Jason C,Berry David C,Chang Wei-Tien,Epstein Jonathan,Hood Natalie,Singletary Eunice M,Zideman David,Lin Steve,
Resuscitation
BACKGROUND:Heat stroke is an emergent condition characterized by hyperthermia (>40 °C/>104 °F) and nervous system dysregulation. There are two primary etiologies: exertional which occurs during physical activity and non-exertional which occurs during extreme heat events without physical exertion. Left untreated, both may lead to significant morbidity, are considered a special circumstance for cardiac arrest, and cause of mortality. METHODS:We searched Medline, Embase, CINAHL and SPORTDiscus. We used Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods and risk of bias assessments to determine the certainty and quality of evidence. We included randomized controlled trials, non-randomized trials, cohort studies and case series of five or more patients that evaluated adults and children with non-exertional or exertional heat stroke or exertional hyperthermia, and any cooling technique applicable to first aid and prehospital settings. Outcomes included: cooling rate, mortality, neurological dysfunction, adverse effects and hospital length of stay. RESULTS:We included 63 studies, of which 37 were controlled studies, two were cohort studies and 24 were case series of heat stroke patients. Water immersion of adults with exertional hyperthermia [cold water (14-17 °C/57.2-62.6 °F), colder water (8-12 °C/48.2-53.6 °F) and ice water (1-5 °C/33.8-41 °F)] resulted in faster cooling rates when compared to passive cooling. No single water temperature range was found to be associated with a quicker core temperature reduction than another (cold, colder or ice). CONCLUSION:Water immersion techniques (using 1-17 °C water) more effectively lowered core body temperatures when compared with passive cooling, in hyperthermic adults. The available evidence suggests water immersion can rapidly reduce core body temperature in settings where it is feasible.
10.1016/j.resuscitation.2020.01.007
Mortality attributable to hot and cold ambient temperatures in India: a nationally representative case-crossover study.
Fu Sze Hang,Gasparrini Antonio,Rodriguez Peter S,Jha Prabhat
PLoS medicine
BACKGROUND:Most of the epidemiological studies that have examined the detrimental effects of ambient hot and cold temperatures on human health have been conducted in high-income countries. In India, the limited evidence on temperature and health risks has focused mostly on the effects of heat waves and has mostly been from small scale studies. Here, we quantify heat and cold effects on mortality in India using a nationally representative study of the causes of death and daily temperature data for 2001-2013. METHODS AND FINDINGS:We applied distributed-lag nonlinear models with case-crossover models to assess the effects of heat and cold on all medical causes of death for all ages from birth (n = 411,613) as well as on stroke (n = 19,753), ischaemic heart disease (IHD) (n = 40,003), and respiratory diseases (n = 23,595) among adults aged 30-69. We calculated the attributable risk fractions by mortality cause for extremely cold (0.4 to 13.8°C), moderately cold (13.8°C to cause-specific minimum mortality temperatures), moderately hot (cause-specific minimum mortality temperatures to 34.2°C), and extremely hot temperatures (34.2 to 39.7°C). We further calculated the temperature-attributable deaths using the United Nations' death estimates for India in 2015. Mortality from all medical causes, stroke, and respiratory diseases showed excess risks at moderately cold temperature and hot temperature. For all examined causes, moderately cold temperature was estimated to have higher attributable risks (6.3% [95% empirical confidence interval (eCI) 1.1 to 11.1] for all medical deaths, 27.2% [11.4 to 40.2] for stroke, 9.7% [3.7 to 15.3] for IHD, and 6.5% [3.5 to 9.2] for respiratory diseases) than extremely cold, moderately hot, and extremely hot temperatures. In 2015, 197,000 (121,000 to 259,000) deaths from stroke, IHD, and respiratory diseases at ages 30-69 years were attributable to moderately cold temperature, which was 12- and 42-fold higher than totals from extremely cold and extremely hot temperature, respectively. The main limitation of this study was the coarse spatial resolution of the temperature data, which may mask microclimate effects. CONCLUSIONS:Public health interventions to mitigate temperature effects need to focus not only on extremely hot temperatures but also moderately cold temperatures. Future absolute totals of temperature-related deaths are likely to depend on the large absolute numbers of people exposed to both extremely hot and moderately cold temperatures. Similar large-scale and nationally representative studies are required in other low- and middle-income countries to better understand the impact of future temperature changes on cause-specific mortality.
10.1371/journal.pmed.1002619