Ultrasound versus nerve stimulation technique for interscalene brachial plexus block: A randomized controlled trial

Introduction and Aims: Peripheral nerve block techniques have evolved over time with the advent of peripheral nerve stimulator and ultrasonography. We intend to compare these two techniques in this study with respect to their efficacy, reliability and safety. Materials and Method: Prospective, randomized, observer-blinded study was conducted on 60 ASA I-II patients posted for surgery of shoulder, clavicle or proximal humerus. They were randomly allocated in to two groups to receive either ultrasound guided (USG group) or peripheral nerve stimulator guided (PNS group) interscalene brachial plexus block with 20 ml of local anaesthetic solution (2% lignocaine with adrenaline 10ml + 0.5% bupivacaine 10 ml). We compared the procedure time, time for adequate sensory and motor block, duration of block, block failure rate, complications and patient satisfaction. Result: Ultrasound significantly reduces the time to conduct the block as compared to PNS. The onset of block was earlier and duration was significantly prolonged (p=0.0001) in USG group. The success rate was 100% and patient satisfaction was significantly better in USG group compared to PNS group. Conclusion: Ultrasound guided technique for interscalene brachial plexus block provides a block which is faster in onset, has prolonged duration, higher success rate and better patient satisfaction compared to PNS guided nerve block