Estimation of the minimum effective volume of 0.5% bupivacaine for ultrasound-guided axillary brachial plexus block.

Given the dose-limiting potential of ultrasound-guided regional anaesthesia techniques, our aim was to estimate the minimum effective volume of 0.5% bupivacaine for axillary brachial plexus blocks (ABPBs) in patients undergoing upper extremity surgery for/with extensive tissue damage (in which prolonged postoperative analgesia would be beneficial). Dose reduction in itself has the advantage of limiting block-related adverse effects.