Comparative Efficacy and Safety of Intravenous Clonidine and Tramadol for Control of Postspinal Anesthesia Shivering

Shivering is a common problem in patients undergoing surgery under spinal anesthesia.

The aim of this study was to compare efficacy and safety of clonidine versus tramadol in postspinal anesthesia shivering.

This prospective, randomized, double-blind controlled clinical trial was conducted in a tertiary care setting.

A total of 60 American Society of Anesthesiologists physical status Class l and II adult patients (age 18-65 years) undergoing surgery under spinal anesthesia and developed shivering received either clonidine 1 μg/kg or tramadol 1 mg/kg intravenously. The time required for cessation of shivering, control and recurrence rate of shivering, effect on hemodynamics and side effects were compared between two groups.

Unpaired t-test and Chi-square test were used for comparison of continuous variables and dichotomous data between two groups, respectively. P < 0.05 was considered as statistically significant.

Time for cessation of shivering was less in clonidine group than tramadol group (02.51 vs. 04.82 min; P < 0.001). Complete control of shivering was achieved in 80% of patients in clonidine group versus 70% in tramadol group. There was no significant difference for control (P = 0.5) and rate of recurrence of shivering between clonidine and tramadol group (06.7% vs. 16.7%; P = 0.42). Pulse rate and systolic blood pressure were significantly lower in clonidine group at 5 and 15 min as compared with tramadol. Significantly more number of patients experienced nausea and dizziness (36.7% vs. 0%; P < 0.001 and 20% vs. 0%; P = 0.01) with tramadol while bradycardia and hypotension were numerically more common in patients receiving clonidine (6.7% vs. 0% and 13.3% vs. 0%).

Clonidine provides early relief from shivering than tramadol with fewer side effects in patients undergoing surgery under spinal anesthesia.