A comparative study of intravenous tramadol versus butorphanol for control of shivering in patients undergoing spinal anesthesia

Background: Shivering in patients following spinal anesthesia is a common problem which is cumbersome for the operating room personnel as well as the patient. Various methods, both pharmacological and non-pharmacological, have been tried to control shivering. This study aimed to evaluate the relative efficacy of intravenously administered butorphanol 20 μg/kg and tramadol 1 mg/kg in controlling shivering following spinal anesthesia in the intraoperative period. Materials and Methods: A prospective, randomized comparative study was conducted in patients who received spinal anesthesia and developed shivering were randomly allotted to one of the two groups, namely butorphanol group who received i.v. 20 μg/kg butorphanol and tramadol group who received i.v. 1 mg/kg tramadol. Vital parameters of the patients such as heart rate, blood pressure, SpO2 , and temperature were monitored at regular intervals as per protocol. Events such as failure to stop shivering, recurrence of shivering, and side effects such as nausea and vomiting were also noted. Statistical tests such as Chi-square test and Student’s t-test (unpaired and paired) were applied to the data collected. Results: Of the 76 patients who developed shivering following spinal anesthesia during the period of study 38 patients received i.v. tramadol and other 38 patients received i.v. butorphanol. The mean temperature at which patients developed shivering was 36.22°C and the mean duration for shivering to occur following spinal anesthesia was 28.82 min. Butorphanol controlled shivering in mean time of 190.53 s while tramadol controlled shivering in mean time of 205.47 s. There was no statistically significant difference between the two groups in terms of time required to control shivering. Butorphanol failed to control shivering in two patient and had recurrence of shivering in seven patients while tramadol which had no failures and no recurrence of shivering. Conclusion: Our study concludes that intravenously administered tramadol 1 mg/kg was more effective in controlling shivering than butorphanol 20 μg/kg following spinal anesthesia. Further, the incidence of nausea and vomiting was more in patients treated with i.v. tramadol in comparison to i.v. butorphanol.