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.