Comparative Study between Single, Double and Intra-Cluster Injection in Ultrasound-Guided Supraclavicular Brachial Plexus Block: A Randomized Trial

Abstract
Background: There are many different approaches for ultrasound-guided supraclavicular brachial plexus block. Each approach has a different success rate and complications.
Aim of Study: The aim of this study is to compare intra-cluster injection technique compared with the most common supraclavicular approach single and double injection tech-niques.
Material and Methods: Thirty-six patients received supr-aclavicular block were divided in to three groups. The total volume of local Anesthetic was 30ml 0.5% bupivacaine, In Gs (n=12) the whole volume was injected at corner pocket, while in Gd (n=12), half the volume of local anesthetic was injected at corner pocket and the other half was injected supero-lateral to subclavian artery. In Gic (n=12) the whole volume was injected inside main and satellite neural cluster. the onset time was recorded as the primary outcome.
Results: Gic showed rapid onset compared to Gs and Gd (8.17±1.64 minutes, 18±2.45 minutes, 12.58±1.83 minutes, p<0.001) respectively. While Gd showed the longest duration than Gic and Gs (444.17±64.73 minutes, 310±50.09 minutes, 125.83±43.32 minutes, p<0.001) respectively. Time of first rescue analgesia was longer in Gd relative to Gic and G s (455±65.68 minute, 337.50±49.38 minutes, 136.67±49.10 minutes, p<0.001). Complication was noticed in only one patient in Gd.
Conclusion: Intra-cluster technique for Supra-Clavicular Brachial Plexus Block showed rapid onset with adequate post-operative analgesia and minimal complications.