Randomized prospective study of three different techniques for ultrasound-guided axillary brachial plexus block

Randomized prospective study comparing two perivascular techniques with the perineural technique for ultrasound-guided axillary brachial plexus block (US-ABPB). The primary objective was to verify if these perivascular techniques are noninferior to the perineural technique. 240 patients were randomized to receive the techniques: below the artery (BA), around the artery (AA) or perineural (PN). The anesthetic volume used was 40mL of 0.375% bupivacaine. All patients received a musculocutaneous nerve blockade with 10mL. In BA technique, 30mL were injected below the axillary artery. In AA technique, 7.5mL were injected at 4 points around the artery. In PN technique, the median, ulnar, and radial nerves were anesthetized with 10mL per nerve. Confidence interval analysis showed that the perivascular techniques studied were not inferior to the perineural technique. The time to perform the blockade was shorter for the BA technique (300.4±78.4s, 396.5±117.1s, 487.6±172.6s, respectively). The PN technique showed a lower latency time (PN – 655.3±348.9s; BA – 1044±389.5s; AA – 932.9±314.5s), and less total time for the procedure (PN – 1132±395.8s; BA – 1346.2±413.4s; AA – 1329.5±344.4s). BA technique had a higher incidence of vascular puncture (BA – 22.5%; AA – 16.3%; PN – 5%). The perivascular techniques are viable alternatives to perineural technique for US-ABPB. There is a higher incidence of vascular puncture associated with the BA technique. Estudo prospectivo randomizado, compara duas técnicas perivasculares com a técnica perineural para o bloqueio do plexo braquial via axilar guiado por ultrassom (BPVA-USG). Objetivo primário foi verificar se essas técnicas perivasculares são não inferiores à técnica perineural. Foram randomizados 240 pacientes para receber as técnicas: abaixo da artéria (TA), ao redor da artéria (TR) ou perineural (PN). O volume de anestésico usado foi 40ml de bupivacaína 0,375%. Em todos os pacientes, fez-se o bloqueio do nervo musculocutâneo com 10ml. Na técnica TA, injetaram-se 30ml abaixo da artéria axilar. Na técnica TR, injetaram-se 7,5ml em quatro pontos ao redor da artéria. Na técnica PN, os nervos mediano, ulnar e radial foram anestesiados com 10ml por nervo. Análise dos intervalos de confiança mostrou que as técnicas perivasculares estudadas não são inferiores à técnica perineural. A técnica TA apresentou menor tempo para o bloqueio (300,4±78,4 seg; 396,5±117,1 seg; 487,6±172,6 seg; respectivamente). A técnica PN apresentou menor tem