Comparison of Ondansetron and Meperidine for Treatment of Postoperative Shivering: A Randomized Controlled Clinical Trial

BACKGROUND The involved neurotransmitter pathways in the postoperative shivering (POS) are poorly understood. Recently, 5-hydroxytryptamine 3 (5-HT3) receptor antagonists have been reported to prevent POS. We investigated the effect of ondansetron, a 5-HT3 antagonist that is used to treat postoperative nausea and vomiting, on shivering. OBJECTIVES This study aimed to compare the efficacy of ondansetron and meperidine in the treatment of shivering after general anesthesia. PATIENTS AND METHODS In this double-blinded randomized clinical trial, 83 patients (age range, 18-60 years) who had shivering after general anesthesia were randomly allocated to any of these three groups: Group A, (number = 27) received 4 mg of intravenous ondansetron, Group B, (number = 27) received 8 mg of intravenous ondansetron, and Group C, (number = 29) received 0.4 mg/kg of intravenous meperidine at recovery room. The surface temperatures and the incidence as well as intensity of shivering were recorded. RESULTS Shivering was controlled in 16 patients (59%) in Group A, 22 (81%) in Group B, and 25 (86%) in Group C (P = 0.01). Within each group, there were no significant differences among the surface temperature in recovery room. Patients in groups A and B had significantly lower incidence of nausea and vomiting than group C (P = 0.01). CONCLUSIONS Ondansetron and meperidine have similar effects on shivering. We concluded that 8 mg of intravenous ondansetron can control shivering and this is the dose of choice, especially in patients with POS with nausea and vomiting.