Clinical Efficacy Of Dexmedetomidine On Post-epidural Anesthesia Shivering

Objective To investigate the clinical efficacy of dexmedetomidine onpost-epidural anesthesia shivering, and the impact on respiration and circulation.Methods Ninety patients who were undergoing lower extremity surgeryunder epidural anesthesia, ASA I-II,18-60yr old, were randomized into threegroups of30individuals.2%lidocaine and0.75%ropivacaine were used duringthe anesthesia. At the same time of epidural anesthesia, the first two groupswere administered a maintenance infusion of0.5μg/kg and0.3μg/kgdexmedetomidine separately for ten minutes, while0.9%physiological saline atthe same amount and duration was infused in group C. Record respiratoryrate（RR）、pulse oxygen saturation （SPO₂）、mean arterial pressure（MAP）、heartrate（HR）and body temperature of eight points.Besides, side effects、ropivacaine quantity and fluid infusion were also noted down. Shivering andsedation were assessed using Wrench classification and OAA/S scale.Results Shivering incidence of A and B group revealed significant decreasecompared with the saline group （P＜0.05）. There were significant decreases ofOAA/S scale in dexmedetomidine groups （P＜0.05）. MAP between T4and T₇,HR between T₃and T₇in group A and B were separately lower than groupC（P＜0.05）. Incidence of sinus bradycardia and the need for intraoperativeatropine were both higher in group A（P＜0.05）. RR、SPO₂and side effectswere not significantly different among three groups.Conclusion Advance injection of0.3μg/kg and0.5μg/kg dexmedetomidinemay be effective in the prevention of post-epidural anesthesia shivering.Besides，it provided sufficient sedation, maintained steady MAP, had littleinhibition to respiration and few side effects. However, the former was superiorin depression of sinus bradycardia.