SciELO - Scientific Electronic Library Online

vol.59 issue6Main concerns of patients regarding the most common complications in the post-anesthetic care unitTotal intravenous anesthesia with target-controlled infusion of remifetanil and propofol for ablation of atrial fibrillation author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Revista Brasileira de Anestesiologia

Print version ISSN 0034-7094On-line version ISSN 1806-907X


BRAGA, Angélica de Fátima de Assunção et al. Influence of local anesthetics on the neuromuscular blockade produced by rocuronium: effects of lidocaine and 50% enantiomeric excess bupivacaine on the neuromuscular junction. Rev. Bras. Anestesiol. [online]. 2009, vol.59, n.6, pp.725-734. ISSN 0034-7094.

BACKGROUND AND OBJECTIVES: The effects of local anesthetics (LA) on neuromuscular transmission and their influence on the neuromuscular blockade produced by competitive neuromuscular blockers have not been fully investigated. The objective of this study was to evaluate, in vitro, the effects of lidocaine and 50% enantiomeric excess bupivacaine (S75-R25) on the neuromuscular blockade produced by rocuronium. METHODS: The rats were divided in five groups (n = 5) according to the drug used: isolated lidocaine, bupivacaine (S75-R25), or rocuronium (groups I, II, and II); and rocuronium in preparations previously exposed to LAs (groups IV and V). The concentrations used were as follows: 20 µg.mL-1, 5 µg.mL-1, and 4 µg.mL-1 of lidocaine, bupivacaine (S75-R25), and rocuronium, respectively. The following parameters were evaluated: 1) the strength of muscular contraction of the diaphragm to indirect electrical stimulations, before and 60 minutes after the isolated addition of the LAs and rocuronium, and the association AL-rocuronium; and 2) the effects of LAs on membrane potential (MP) and miniature end-plate potentials (MEPP). The effect of LAs on muscle contraction in response to acetylcholine was evaluated in chick biventer cervicis preparations. RESULTS: Isolated lidocaine and bupivacaine (S75-R25) did not change the muscular response and the levels of MPs. In preparations exposed to LAs, rocuroniuminduced blockade was significantly greater than that produced by rocuronium alone. In chick biventer cervicis preparations, lidocaine and bupivacaine (S75R25) decreased contraction in response to acetylcholine. Lidocaine increased the frequency of MEPPs, which was followed by the blockade; bupivacaine (S75R25) caused a reduction in MEPPs followed by blockade. CONCLUSIONS: Local anesthetics caused a potentiation of the neuromuscular blockade produced by rocuronium. The results showed pre- and post-synaptic effects.

Keywords : ANESTHETICS, Local [bupivacaine (S75-R25)]; ANESTHETICS, Local [lidocaine]; ANIMALS [rats]; NEUROMUSCULAR BLOCKERS, Non-depolarizing [rocuronium].

        · abstract in Portuguese | Spanish     · text in English | Portuguese     · English ( pdf epdf ) | Portuguese ( pdf epdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License