Minimum effective volume of 0.5% bupivacaine with epinephrine in ultrasound-guided interscalene brachial plexus block.

BACKGROUND: The use of ultrasound (US) in regional anaesthesia enables a reduction in the local anaesthetic volume. The present study aimed to determine the minimum effective volume (MEV(90)) of 0.5% bupivacaine with epinephrine for interscalene brachial plexus block (ISBPB). METHODS: The volume of the anaesthetic was determined using a step-up/step-down method and was based on the outcome of the preceding block. A positive or negative block resulted in a 1 ml reduction or increase in volume, respectively. The success of the block was defined as the presence of motor block in three muscle groups and the absence of thermal and pain sensations in three dermatomes within 30 min of the injection. Diaphragmatic paralysis and analgesia were assessed at 30 min, 4, and 6 h. RESULTS: The MEV(90) for US-guided brachial plexus block under the conditions of the present study was 0.95 ml [R(2): 0.97, 95% confidence interval (CI): 0.6-1.22 ml]. The estimated maximum volume that did not cause diaphragmatic block was 4.29 ml (R(2): 0.84, 95% CI: 3.56-4.98 ml). Effective postoperative analgesia was achieved with 2.34 ml (R(2): 0.87, 95% CI: 0.48-11.47 ml). CONCLUSIONS: The MEV(90) of 0.5% bupivacaine with epinephrine (1:200 000) for US-guided ISBPB was 0.95 ml. Adequate postoperative analgesia and a reduced incidence of diaphragmatic block can be obtained using from 2.34 to 4.29 ml. ClinicalTrials.gov. Registry NCT01244932.

Efeitos do cloridrato de morfina peridural na glicemia de pacientes submetidos a anestesia geral. / Effects of epidural morphine hydrochloride in glycemia of patients subjected to general anesthesia

Os autores estudaram as alteracoes glicemicas pre-operatorias de 36 pacientes com estado fisico ASA I, sem antecedentes diabeticos, com glicemia de jejum normal e que foram submetidos a cirurgias eletivas do abdomen superior.Os pacientes foram divididos em grupos A e B conforme eram levados ao centro cirurgico na hora da cirurgia ou uma hora antes, respectivamente.Os grupos A e B foram subdivididos em dois sub-grupos: A1 e B1 que constituiram o nosso grupos controle e A2 e B2 que receberam 5 mg de morfina no espaco peridural.No sub-grupo A2 injecao de cloridrato de morfina foi realizada logo apos a inducao anestesica e no sub-grupo B2, uma hora antes da inducao. A analise dos resultados mostrou aumentos significantes nos niveis glicemicos dos sub-grupos A1 e B2 e nas duas primeiras horas de cirurgia do sub-grupo A2 que se comportou depois de duas cirurgia, semelhante ao B2 cujos niveis glicemicos nao foram alterados significativamente