1. 2019;19;243-253Safety and Efficacy of Dexmedetomidine in Treating Post Spinal Anesthesia Shivering: A Randomized Clinically Controlled Dose-Finding Trial
   Randomized Trial
   Mohamed Abdel-Kadr Osman, PhD, Khaled M. Fares, MD, Hala Saad Abdel-Ghaffar, MD, and Sahar Abd-Elbaky Mohamed, MD.

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