Safety and Efficacy of Dexmedetomidine in Treating Post Spinal Anesthesia Shivering: A Randomized Clinically Controlled Dose-Finding Trial

Abstract

Background: The optimum dose of dexmedetomidine for shivering control with the least hemodynamic derangements is still under research. Objective: To compare the efficacy, hemodynamic and side effects of dexmedetomidine in 3 different doses with those of meperidine for the treatment of shivering in patients undergoing spinal anesthesia for minor elective lower abdominal surgery. Study Design: Prospective double-blind randomized clinically controlled study. Setting: University hospital. Methods: One hundred twenty patients who developed shivering under spinal anesthesia. On shivering, patients were randomly allocated to receive an intravenous 2 mL bolus dose of meperidine 0.4 mg/kg (meperidine group, n = 30), dexmedetomidine 0.5 µg/kg (DEX I group, n = 30), 0.3 µg/kg (DEX II group, n = 30), or 0.2µg/kg (DEX III group, n = 30). Control of shivering, time taken for cessation of shivering, response rate, recurrence, hemodynamic changes, sedation score, tympanic temperature, and side effects were noted and compared between groups. Results: The groups were comparable regarding demographic profile, tympanic temperature decline, and shivering onset time (P > 0.05). Lower shivering cessation time (P < 0.001) and higher response rate (P < 0.01) were observed in DEX I and II groups compared with DEX III and meperidine groups, with a nonsignificant difference between DEX I and II groups. Recurrence of shivering activity was higher in DEX III group (36.7%, P < 0.01) compared with DEX I (10%), DEX II (6.7%) and meperidine (16.7%) groups. Lower heart rates, systolic and diastolic blood pressure mean values were recorded in DEX I group (P < 0.05). Nine patients (30%) in DEX I group were in levels 3 – 5 of sedation (P < 0.02) compared with 5 (16.66%), 2 (6.66%), and 4 (13.3) patients in DEX II, DEX III, and meperidine groups, respectively. Limitations: This study is limited by its small sample size. Conclusions: Among the 3 doses investigated, dexmedetomidine 0.3µg/kg effectively treated shivering associated with spinal anesthesia with modest hemodynamic and sedation effects. Trial Registration: ClinicalTrials.gov Identifier: NCT02382432. Key words: Dexmedetomidine, hypothermia, shivering, spinal anesthesia