Efficacy of multimodal analgesia with perineural buprenorphine or dexmedetomidine for surgeries performed under ultrasound-guided infraclavicular brachial plexus block

Background and Aims: Perineural adjuvants when used as a part of multimodal analgesia (MMA) will maximize the quality and duration of analgesia of the nerve blocks. In the present study, we compared the duration of postoperative analgesia and other block characteristics of two groups of MMA comprising either perineural buprenorphine or dexmedetomidine in the upper limb surgeries performed under ultrasound-guided (US-guided) infraclavicular brachial plexus blocks. Material and Methods: A total of 100 adult patients undergoing elective upper limb orthopedic surgery under US-guided infraclavicular brachial plexus block were randomly divided into two groups. Group I received 150 mu g buprenorphine and Group II received 50 mu g dexmedetomidine, perineurally added to 30 ml of 0.375% bupivacaine. Both groups also received tramadol 50 mg IV, dexamethasone 4 mg IV, and diclofenac 75 mg infusion as part of MMA. Both groups were compared for the duration of postoperative analgesia, block characteristics, and incidence of adverse effects. Results: The duration of postoperative analgesia was significantly prolonged in Group II (937.6 +/- 179.1 min vs 1280.4 +/- 288.8 min). The onset of sensory and motor blocks was shorter in Group II (P < 0.05). The duration of sensory and motor blocks was significantly prolonged in Group II (P < 0.05). The number of rescue analgesics required in the first 24 hours was less in Group II (1.98 +/- 0.62 vs 0.8 +/- 0.64). Although heart rate and blood pressure levels were lower in Group II, all patients were hemodynamically stable. Conclusion: For surgeries under brachial plexus block, perineural dexmedetomidine when used as a part of MMA provided a prolonged duration of postoperative analgesia and improved block characteristics than perineural buprenorphine.