High-dose dexmedetomidine versus dexamethasone supplementation to interscalene brachial plexus block in arthroscopic shoulder surgery: A randomized, controlled trial.

Study Summary

112 patients undergoing arthroscopic shoulder surgery were randomized to receive ultrasound-guided interscalene brachial plexus block (ISB) with bupivacaine supplemented with either high-dose dexmedetomidine (2 µg/kg) or dexamethasone (5 mg). The primary outcome was duration of analgesia (DOA), defined as the time from block administration to the first report of pain or rescue analgesia. Secondary outcomes included duration of sensory block (DOS), duration of motor block (DOM), numerical rating scale (NRS) pain scores, rebound pain, opioid consumption, patient satisfaction, and adverse events. Outcomes were assessed up to 30 hours postoperatively. Overall, the results revealed no significant difference in DOA between treatments, although dexmedetomidine significantly prolonged DOS and DOM. However, dexmedetomidine was associated with higher rates of hypotension, bradycardia, and postoperative sedation. These findings suggested that high-dose dexmedetomidine offered no demonstrated analgesic advantage over dexamethasone and raised additional safety concerns.