Analysis of lung ventilation variation with electrical impedance tomograph after interscalene brachial plexus block

Objetivo: Avaliação da ventilação pulmonar após a realização de bloqueio de plexo braquial com auxílio de tomógrafo de impedância elétrica em cirurgias de ombro em regime ambulatorial. Métodos: Os pacientes foram randomizados em dois grupos para realização de bloqueio do plexo braquial pela via interescalênica guiado por ultrassom com 4 e 15 mL de bupivacaína a 0,5% com adrenalina ao redor da raiz de C6. Tiveram sua ventilação avaliada em 3 momentos: antes do bloqueio (T0), 30 minutos (T1) e 4 horas após o bloqueio (T2). Após a segunda aferição, foram submetidos a anestesia geral e ao final do procedimento cirúrgico após reversão do bloqueio neuromuscular e recrutamento alveolar foram extubados e 4 horas após o bloqueio foram submetidos a nova aferição. Resultados: A ventilação apresenta valores menores aos 30 minutos no grupo 15 mL em comparação com 4 mL sendo que a recuperação dos valores iniciais da ventilação após 4 horas se mostra próxima ao observado em ambos os grupos. Apesar das diferenças apresentadas entre os grupos na variável estudada estas não foram estatisticamente significativas em nenhum momento. Conclusões: O impacto do bloqueio interescalênico sobre a ventilação se mostrou pequeno na população estudada com a técnica escolhida, sendo a principal alteração ventilatória nos primeiros 30 min no grupo de 15mL. Após 4 horas os parâmetros analisados se encontram próximos aos aferidos inicialmente. A ausência de diferença estatística após 4 horas nos valores da ventilação chama a atenção para a semelhança de efeito entre os grupos, mesmo que o volume mínimo e anestésico local utilizado seja 4 mL.Objective: Assessment of lung ventilation after performing brachial plexus block with the aid of an electrical impedance tomograph in outpatient shoulder surgeries. Methods: Patients were randomly allocated into two groups to receive ultrasound-guided interscalenic brachial plexus block with 4 or 15 mL of bupivacaine 0.5% with epinephrine around the C6 root. They had their ventilation evaluated in 3 moments: before the blockade (T0), 30 minutes (T1) and 4 hours after the blockade (T2). Following the second measurement, they underwent general anesthesia. At the end of the surgical procedure, subsequently of the decurarization and alveolar recruitment, they were extubated and reevaluated after 4 hours of the blockade. Results: Pulmonary ventilation presents lower values at 30 minutes in the 15 mL group compared to 4 mL and the recovery of ventilation values after 4 hours is close to that observed initially in both groups. Despite the differences shown between the groups in the variables studied, these were not statistically significant at any time. Conclusions: The impact of interscalene block on pulmonary ventilation was small in the population studied with the chosen technique, with the main ventilatory alteration being in the first 30 min in the 15mL group and after 4 hours the parameters analyzed are close to those measured initially

Ultrasound-guided selective nerve blocks for trigger finger surgeries to maintain flexion/extension of fingers – Case series

Background: A patient's ability to move his/her fingers during hand surgery may be helpful to surgeons because it allows the effectiveness of the intervention evaluation and prediction of hand function in the postoperative period. The purpose of this case series is to demonstrate the efficacy of an ultrasound-guided peripheral nerve block technique to maintain the hand flexor and extensor muscles motor function and discuss the benefits of the technique for trigger finger surgery. Case report: Ten patients scheduled to undergo trigger finger surgery were selected. The goal was to maintain flexion and extension of the fingers during the procedure. Thus, ultrasound-guided ulnar, radial, and medial nerve block was performed in the distal third of the forearm, at 5–7 cm proximal to the wrist. The block was performed with 5 mL of 0.375% bupivacaine on each nerve. All procedures were uneventfully performed maintaining the flexion and extension of the fingers. In two cases, it was observed that the motricity maintenance and the patients’ ability to move their fingers when requested allowed the success of the surgical procedure after the third intraoperative evaluation. Conclusion: This case series shows that it is possible to maintain the motor function of the hand flexor and extensor muscles to perform finger trigger surgeries using specific ultrasound-guided distal blocks. Resumo: Justificativa: A capacidade de um paciente mover os dedos durante a cirurgia da mão pode ser útil para o cirurgião porque permite a avaliação da eficácia da intervenção e a predição da função da mão no pós-operatório. O objetivo desta série de casos é demonstrar a eficácia de uma técnica de bloqueio de nervo periférico guiado por ultrassom na manutenção da função motora dos músculos flexores e extensores da mão e discutir os benefícios da técnica para cirurgias de liberação de dedo em gatilho. Relato de caso: Foram selecionados 10 pacientes em programação para cirurgia de liberação de dedo em gatilho. O objetivo era manter a flexão e a extensão dos dedos durante o procedimento. Dessa forma, o bloqueio dos nervos ulnar, radial e mediano, guiados por ultrassom, foi feito no terço distal do antebraço, 5 a 7 cm proximais ao punho. O bloqueio foi feito com 5 mL de bupivacaína a 0,375% em cada nervo. Todos os procedimentos foram feitos sem complicações e com manutenção da flexão e extensão dos dedos. Em dois casos, observou-se que a manutenção da motricidade e a capacidade dos pacientes de mover os dedos quando solicitado permitiu o sucesso do procedimento cirúrgico após a terceira avaliação intraoperatória. Conclusão: Esta série de casos mostra que é possível manter a função motora dos músculos flexores e extensores da mão em cirurgias de liberação de dedo em gatilho por meio de bloqueios distais específicos guiados por ultrassom. Keywords: Selective nerve blocks, Ultrasound, Flexion and extension of the fingers, Trigger finger release, Palavras-chave: Bloqueios seletivos, Ultrassom, Flexão e extensão dos dedos, Liberação dedo em gatilh

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

Introduction: 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. Method: 240 patients were randomized to receive the techniques: below the artery (BA), around the artery (AA) or perineural (PN). The anesthetic volume used was 40 mL of 0.375% bupivacaine. All patients received a musculocutaneous nerve blockade with 10 mL. In BA technique, 30 mL were injected below the axillary artery. In AA technique, 7.5 mL were injected at 4 points around the artery. In PN technique, the median, ulnar, and radial nerves were anesthetized with 10 mL per nerve. Results: 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 +/- 78.4 s, 396.5 +/- 117.1 s, 487.6 +/- 172.6 s, respectively). The PN technique showed a lower latency time (PN - 655.3 +/- 348.9 sBA - 1044 +/- 389.5 sAA -932.9 +/- 314.5 s), and less total time for the procedure (PN - 1132 +/- 395.8 sBA - 1346.2 +/- 413.4 sAA -1329.5 +/- 344.4 s). BA technique had a higher incidence of vascular puncture (BA -22.5%AA -16.3%PN - 5%). Conclusion: 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. (C) 2017 Published by Elsevier Editora Ltda. on behalf of Sociedade Brasileira de Anestesiologia.Univ Fed Sao Paulo UNIFESP, EPM, Disciplina Anestesiol Dor & Med Intens, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, EPM, Disciplina Anestesiol Dor & Med Intens, Sao Paulo, SP, BrazilWeb of Scienc

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

Abstract Introduction 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. Method 240 patients were randomized to receive the techniques: below the artery (BA), around the artery (AA) or perineural (PN). The anesthetic volume used was 40 mL of 0.375% bupivacaine. All patients received a musculocutaneous nerve blockade with 10 mL. In BA technique, 30 mL were injected below the axillary artery. In AA technique, 7.5 mL were injected at 4 points around the artery. In PN technique, the median, ulnar, and radial nerves were anesthetized with 10 mL per nerve. Results 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 ± 78.4 s, 396.5 ± 117.1 s, 487.6 ± 172.6 s, respectively). The PN technique showed a lower latency time (PN - 655.3 ± 348.9 s; BA - 1044 ± 389.5 s; AA - 932.9 ± 314.5 s), and less total time for the procedure (PN - 1132 ± 395.8 s; BA - 1346.2 ± 413.4 s; AA - 1329.5 ± 344.4 s). BA technique had a higher incidence of vascular puncture (BA - 22.5%; AA - 16.3%; PN - 5%). Conclusion 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