Comparison of Low Dose Intrathecal Buprenorphine and Clonidine as an Adjuvant to Bupivacaine in Spinal Anesthesia for Post-Operative Analgesia in Lower Limb and Lower Abdominal Surgeries

Post-Operative Analgesia in Lower Limb and Lower Abdominal Surgeries

Abstract

Background: Management of postoperative pain is an important part of post-operative care. Spinal anesthesia when used with adjuvants can prolong analgesia well into the early postoperative period and is one of the commonly used methods in most lower abdominal and lower limb surgeries. Various studies have been done using higher doses of adjuvants. However, relatively fewer studies have been done using lower doses of these drugs. In this study, low doses of intrathecal buprenorphine and clonidine used as an adjuvant in spinal anaesthesia were compared     in providing effective postoperative analgesia. Subjects & Methods: 100 ASA 1 and 2 patients who were planned for lower abdominal and lower limb surgeries were enrolled in our study and were randomly divided into 2 groups of 50 each- Group X and Y. Patients with a known allergy, on ? blockers, ?2 agonists, basal heart rate 50/min, pregnant and lactating women, obesity- BMI  30 were excluded from the study. The patients in group X received 15mg (3 ml) of 0.5% hyperbaric bupivacaine with 45g (0.15 ml) of buprenorphine and patients in group Y received 15 mg (3 ml) of 0.5% hyperbaric bupivacaine with 22.5g (0.15 ml) of clonidine. The duration of analgesia- the time to request for first rescue analgesic and the number of doses of systemic analgesics in the first 24 hrs postoperatively was noted. Results: The time to request for the first rescue analgesic was significantly longer in group X(buprenorphine) when compared to group Y(clonidine) with a p-value <0.001. Also, the mean requirement of the total number of analgesics was less in group X when compared to group Y and was statistically significant with a p-value <0.001. Conclusion: We conclude that intrathecal adjuvants buprenorphine and clonidine, even in low doses, provide effective postoperative analgesia and buprenorphine has a longer analgesic effect when compared to clonidine.