Dexmedetomidine Improves Cardiovascular and Ventilatory Outcomes in Critically Ill Patients: Basic and Clinical Approaches.
Castillo Rodrigo L,Ibacache Mauricio,Cortínez Ignacio,Carrasco-Pozo Catalina,Farías Jorge G,Carrasco Rodrigo A,Vargas-Errázuriz Patricio,Ramos Daniel,Benavente Rafael,Torres Daniela Henríquez,Méndez Aníbal
Frontiers in pharmacology
Dexmedetomidine (DEX) is a highly selective α2-adrenergic agonist with sedative and analgesic properties, with minimal respiratory effects. It is used as a sedative in the intensive care unit and the operating room. The opioid-sparing effect and the absence of respiratory effects make dexmedetomidine an attractive adjuvant drug for anesthesia in obese patients who are at an increased risk for postoperative respiratory complications. The pharmacodynamic effects on the cardiovascular system are known; however the mechanisms that induce cardioprotection are still under study. Regarding the pharmacokinetics properties, this drug is extensively metabolized in the liver by the uridine diphosphate glucuronosyltransferases. It has a relatively high hepatic extraction ratio, and therefore, its metabolism is dependent on liver blood flow. This review shows, from a basic clinical approach, the evidence supporting the use of dexmedetomidine in different settings, from its use in animal models of ischemia-reperfusion, and cardioprotective signaling pathways. In addition, pharmacokinetics and pharmacodynamics studies in obese subjects and the management of patients subjected to mechanical ventilation are described. Moreover, the clinical efficacy of delirium incidence in patients with indication of non-invasive ventilation is shown. Finally, the available evidence from DEX is described by a group of Chilean pharmacologists and clinicians who have worked for more than 10 years on DEX.
Enhanced Perioperative Safety and Comfort During Airway-Related Surgeries and Procedures With Dexmedetomidine-A Brief Review and Clinical Practice Experience.
Wang Juei-Chii,Yang Tsorng-Shyang,Chen Po-Heng,Huang Wei-Hsiu,Hsiao Szu-Yun,Wong Chih-Shung,Guo Shu-Lin
Asian journal of anesthesiology
Dexmedetomidine, an α-2 adrenergic receptor agonist, provides analgesia, sedation, anxiolysis, sympatholysis and anesthetic-sparing effect, without inducing significant respiratory depression. Due to these properties, its clinical use is no longer limited to serving as a sedative agent in the intensive care unit. Proper airway management and the avoidance of cardiac and respiratory complications are common goals of everyday anesthesia practice. Ensuring airway safety is pivotal during the anesthesia stages of induction, maintenance and recovery. In this review, we focus on the advantages of dexmedetomidine in awake fiberoptic intubation (AFOI), diagnostic examinations and surgeries of patients with obstructed airways, and reducing emergence delirium effectively without causing further adverse events. With increasing implementation in different anesthetic scenarios, dexmedetomidine provides a favorable option to enhance patient safety and comfort.
Effects of dexmedetomidine and propofol on sedation in patients after coronary artery bypass graft surgery in a fast-track recovery room setting.
Karaman Yucel,Abud Burcin,Tekgul Zeki Tuncel,Cakmak Meltem,Yildiz Murside,Gonullu Mustafa
Journal of anesthesia
PURPOSE:We aim to compare the effects of propofol and dexmedetomidine infusions on extubation times, hemodynamic and respiratory functions, complication rates and patient satisfaction scores in patients undergoing coronary artery bypass graft (CABG) surgery using a fast-track anesthesia regimen for early extubation. METHODS:We enrolled 64 patients who underwent CABG surgery. Dexmedetomidine (min 0.2 µg/kg/h-max 1.0 µg/kg/h) and propofol (min 1.0 mg/kg/h-max 3.0 mg/kg/h) infusion doses were titrated to give bispectral index values between 60 and 90 and a Ramsay sedation score (RSS) between 3 and 4. Postoperative extubation times, patient satisfaction and postoperative adverse events were recorded. RESULTS:The mean times to extubation were 265.94 ± 43.1 min for the dexmedetomidine group and 322.52 ± 39.2 min for the propofol group (P < 0.001). In all recordings, RSS median values for the propofol group were significantly lower than the dexmedetomidine group (P < 0.05). There were no differences in the incidence of postoperative adverse events between the dexmedetomidine and propofol groups. There was a statistically significant difference between patient satisfaction median values of the two groups-7 (5-9) and 9 (7-10) (min-max) for the propofol and dexmedetomidine groups, respectively (P < 0.001). CONCLUSION:Our results show that dexmedetomidine can easily be preferred over propofol in fast-track cardiac anesthesia due to its significant advantages of shorter extubation time and higher postoperative patient satisfaction scores.
Effects of intravenous dexmedetomidine in humans. I. Sedation, ventilation, and metabolic rate.
Belleville J P,Ward D S,Bloor B C,Maze M
Dexmedetomidine (DMED) is a highly selective centrally acting alpha 2-adrenergic agonist thought to provide significant sedation without appreciable ventilatory effects. This double-blind, placebo-controlled experiment evaluated four dose levels of DMED (0.25, 0.5, 1.0, and 2.0 micrograms/kg intravenously over 2 min) in 37 healthy male volunteers. Measurements of sedation, arterial blood gases, resting ventilation, hypercapnic ventilatory response (HVR), and metabolic rate (O2 consumption and CO2 production) were performed at baseline, 10 min after DMED infusion, and thereafter at the end of each subsequent 45-min period. DMED caused sedation resulting in loss of responsiveness in most of the subjects administered 1.0 and 2.0 micrograms/kg; sedation was evident for 195 min following 2.0 micrograms/kg (P < .05). Ten minutes following infusion of 1.0 and 2.0 micrograms/kg, PaCO2 had increased by 5.0 and 4.2 mmHg, respectively (P < .05), and 60 min following 2.0 micrograms/kg, VE had decreased by 28% (P < .05). The placebo group showed a progressive increase in the HVR slope (50% increase by 330 min following the infusion; P < .05). Overall, across all the DMED doses, the slope was decreased (P < .05) at all times after DMED. The calculated ventilation at a PaCO2 of 55 mmHg was decreased (39%; P < .05) 10 min following 1.0 and 2.0 micrograms/kg, returning to control values by 285 min following 2.0 micrograms/kg. O2 consumption increased 16% (P < .05) at 10 min following 2.0 micrograms/kg; CO2 production decreased (22% at 60 min). By 5 h postinfusion, both had returned to normal.(ABSTRACT TRUNCATED AT 250 WORDS)
Dexmedetomidine-remifentanil vs propofol-remifentanil for monitored anesthesia care during hysteroscopy: Randomized, single-blind, controlled trial.
Park Seongjoo,Choi Soo-Lyoen,Nahm Francis Sahngun,Ryu Jung-Hee,Do Sang-Hwan
BACKGROUND:Although dexmedetomidine has been used as either the anesthetic agent for light sedation or as an adjunct to other sedatives, no study has investigated the usefulness of dexmedetomidine as the main sedative agent for invasive and painful procedures. The purpose of this study was to compare the safety of dexmedetomidine-remifentanil and propofol-remifentanil during monitored anesthesia care (MAC) for hysteroscopy. METHODS:Female patients undergoing hysteroscopy were randomly assigned to either the dexmedetomidine (group D) or the propofol group (group P). The study drug (0.6 ml/kg; dexmedetomidine 2 μg/ml or propofol 4 mg/ml) was loaded for 10 minutes followed by 0.1 to 0.5 ml/kg/hour to maintain a bispectral index of 60 to 80 during the procedure. In both groups, remifentanil was infused using a target-controlled-infusion system with a target concentration of 2 ng/ml and titrated during the procedure. The incidence rates of intraoperative respiratory depression in both groups were compared. Postoperative pain and patients satisfaction were also compared. RESULTS:A total of 69 female patients were included in this study. Dexmedetomidine significantly decrease the incidence of respiratory depression compared with propofol (15/34 [44.1%] vs 5/35 [14.3%], P = .006, group P and D, respectively). Postoperative pain and patients satisfaction score did not differ between the groups. CONCLUSION:The combination of dexmedetomidine-remifentanil can reduce the incidence of respiratory depression without increasing hemodynamic complications compared with propofol-remifentanil for MAC during hysteroscopy.