Tramadol versus meperidine in the treatment of shivering during spinal anesthesia in cesarean section

BACKGROUND: The aim of this study was to evaluate the efficacy and side effects of tramadol comparing with meperidine on post-spinal shivering in cesarean section. METHODS: In a prospective, controlled, randomized, double-blind clinical trial 73 ASA-I pregnant patients candidates of cesarean section under spinal anesthesia who had shivering postoperatively were selected and classified into two groups receiving tramadol or meperidine to control postoperative shivering. Spinal anesthesia was done by injection of epinephrinized 5% lidocaine at L3-L4 or L4-L5 segment. Pruritis, somnolence, dizziness, nausea, vomiting and the duration of shivering control were evaluated and recorded. All data were analyzed by using Fisher and Chi-square tests. RESULTS: There were no significant differences between two groups in age (P = 0.1) and weight (P = 0.8) of patients. There was no significant difference in response rate after injection of both drugs (P = 0.3). The time elapsed from treatment to ceased shivering was significantly less (P = 0.001) but frequency of somnolence (P = 0.001), nausea (P = 0.001) and vomiting (P = 0.005) were significantly more in tramadol group. Dizziness was significantly more common in meperidine group (P = 0.001) and pruritis was not seen in any group. CONCLUSION: Tramadol is more effective in controlling post-spinal shivering but results in more frequent nausea, vomiting and somnolence in comparison with meperidine. KEYWORDS: Shivering, meperidine, tramadol, spinal anesthesia, cesarean section.