Evaluation of Analgesic Efficacy of Intrathecal Buprenorphine versus Tramadol as Adjuvants to Bupivacaine: A Comparative Study

Background: Intrathecal adjuvants are widely used to enhance the quality and duration of spinal anaesthesia, especially in infra-umbilical surgeries. Buprenorphine, a partial μ-opioid receptor agonist, and tramadol, a centrally acting atypical opioid, have both been used as adjuvants to local anaesthetics like bupivacaine. However, their comparative efficacy and safety in prolonging postoperative analgesia remain subjects of clinical interest. Objective: To compare the efficacy of intrathecal bupivacaine with buprenorphine versus bupivacaine with tramadol in terms of onset and duration of sensory and motor block, postoperative analgesia, and associated side effects in patients undergoing lower abdominal and lower limb surgeries. Methods: A prospective, randomized comparative study was conducted at Department of Anaesthesia, Shaheed Nirmal Mahto Medical College, Dhanbad, Jharkhand, India. A total of 100 ASA Grade I and II patients aged 1860 years undergoing elective lower abdominal or lower limb surgeries were enrolled and divided equally into two groups (n=50 each). Group B received 3 mL of 0.5% hyperbaric bupivacaine with 60 µg buprenorphine, while Group T received 3 mL of 0.5% hyperbaric bupivacaine with 25 mg tramadol intrathecally. Parameters assessed included onset and duration of sensory and motor block, duration of effective analgesia, and incidence of adverse effects. Results: Group B (buprenorphine) showed significantly prolonged duration of postoperative analgesia (412 ± 38 minutes) compared to Group T (tramadol) (316 ± 41 minutes) (p < 0.001). Onset of sensory block was faster in Group T, while motor block onset and duration were comparable. Mild side effects such as nausea and pruritus were noted more frequently in Group B but were self-limiting and did not require intervention. Conclusion: Buprenorphine as an intrathecal adjuvant to bupivacaine provides more prolonged and effective postoperative analgesia compared to tramadol, making it a preferable choice in spinal anaesthesia for lower abdominal and limb surgeries despite minor tolerable side effects.