Long-duration upper extremity surgery under brachial plexus block combined with intravenous dexmedetomidine sedation...

Dexmedetomidine (DEX) provides a unique conscious sedation without respiratory depression. We examined the usefulness of intravenous (IV) DEX sedation combined with brachial plexus block for long-duration upper extremity surgery without an anesthesiologist.

We retrospectively reviewed 90 limbs of 86 patients and measured the actual operative time course in detail. The adverse events and the patient-reported outcomes regarding intraoperative pain and depth of sedation were evaluated.

The mean total time of the operation, tourniquet use, and the IV DEX sedation were 150 min, 132 min, and 117 min, respectively. The mean time between discontinuation of IV DEX sedation and completion of the operation was 51 min. The intraoperative adverse events involved bradycardia (21%), hypotension (18%), and oxygen desaturation (3%). The mean visual analog scale scores of pain during brachial plexus block, surgical site pain, tourniquet pain, and depth of the sedation were 23.4 mm, 0.14 mm, 4.2 mm, and 6.6 mm, respectively. Furthermore, 96% patients expressed a preference for receiving anesthesia as brachial plexus block with IV DEX sedation.

Long-duration upper extremity surgery, even longer than 2 h, was feasible under brachial plexus block combined with IV DEX sedation without an anesthesiologist. For patients with low blood pressure and/or low heart rate, it is recommended to adjust the continuous infusion of IV DEX to less than 0.4 µg/kg/h. To ensure that the patients are able to promptly leave the operating room fully awake, IV DEX infusion should be stopped at least 30 min before finishing the operation.