Bupivacaine–lidocaine versus bupivacaine–lidocaine plus dexamethasone in supraclavicular brachial plexus block

Background To evaluate whether dexamethasone as an adjuvant to bupivacaine–lidocaine mixture in supraclavicular brachial plexus block can enhance the block, prolong the duration of action, and improve postoperative analgesia than a mixture of bupivacaine–lidocaine only. Patients and methods In all, 60 patients were posted for elective and emergent upper limb orthopedic surgery (below shoulder joint), under supraclavicular brachial plexus block guided by a nerve stimulator. Patients were randomly divided into two equal groups: group C (the control group, n=30) received 40 ml solution containing local anesthetics only. Group D (the dexamethasone group, n=30) received a 40 ml solution containing local anesthetics plus 4 mg dexamethasone. Primary outcomes were onset time of sensory and motor block, and duration of sensory and motor block, which were assessed in minutes. Secondary outcomes were pain assessment using a scoring system based on the visual analog scale, time to first analgesic requirement, and total analgesic consumption. Results Duration of sensory and motor block in the dexamethasone group were significantly longer than the control group (753±68.04 vs. 565±30.85 min and 733.66±69.77 vs. 547.16±29.38 min, respectively). For visual analog scale, while comparing the two groups, the differences were significant at 9, 12, and 18 h after surgery in favor of the dexamethasone group. The time to first analgesic request was significantly longer in the dexamethasone group in comparison to the control group. The total analgesic requirement was also significantly lower in the dexamethasone group in comparison to the control group. Conclusion The use of dexamethasone at a dose of 4 mg as an adjuvant to local anesthetics provided effective prolongation in the duration of sensory and motor block, prolonged time to first analgesic request, and reduced the total analgesic consumption.