Comparison of intravenous butorphanol, ondansetron and tramadol for control of shivering during regional anesthesia: a prospective, randomized double-blind study

We conducted this study to compare the efficacy and safety of butorphanol, ondansetron and tramadol for control of shivering in patients undergoing surgical procedures under spinal anesthesia. In this prospective double-blind, randomized, controlled study, 150 patients of both genders, 18-60 years old, ASA I or II, booked for elective surgery under spinal anesthesia were randomly distributed into three groups of 50 each. Each patient, who developed shivering, was given either 0.03 mg/kg of inj. butorphanol 1% [Group-B], 0.06 mg/kg of inj. ondansetron [Group-O] or 1.0 mg/kg of inj. tramadol 1% [Group-T] IV. Demographic characteristics, incidence of shivering, response rate after 1, 3, 5, 10 and 20 min, recurrence rate, hemodynamic parameters and complications were observed. All patients were relieved of shivering after butorphanol; 66.6% of them were relieved within 1 min, 93.33% within 3 min and 100% within 5 min. Ondansetron could relieve shivering in only 29.4% of the patients; 5.88% within 1, 11.76% within 3, 23.52% within 10 and 29.4% within 20 min. Tramadol relieved shivering in 92.30%; 46.15% within 1, 84.61% within 3 and 92.30% within 5 min respectively [p < 0.05]. Recurrence of shivering was observed in 26.67% of butorphanol group and 15.38% of tramadol group [p> 0.05]. Ondansetron was not found to be much effective for the control of shivering during regional anesthesia. Butorphanol and tramadol were equally effective in controlling shivering under regional anesthesia, the only difference being in their onset of action. Butorphanol was quicker in onset which is essential for control of shivering and should be preferred