Article Test

Abstract

Justification and objectives: There are few clinical and experimental studies on the interaction between local anaesthetics and nondepolarising neuromuscular blocking agents and their effects on the neuromuscular junction. However, potentiation of these drugs has been observed when they are used simultaneously. The aim of this study was to evaluate in vitro the efficacy of neostigmine and 4-aminopyridine in the reversal of a neuromuscular block produced by pancuronium combined with different local anaesthetics.

Method: Rats were distributed in groups (n = 5), according to drug combinations: pancuronium + levobupivacaine and pancuronium + enantiomeric mixture. The concentrations of levobupivacaine, enantiomeric mixture and pancuronium were respectively 5µg.mL^-1, 5µg.mL^-1 and 2µg.mL^-1. Neostigmine and 4-aminopyridine were used in concentrations of 2µg.mL^-1 and 20µg.mL^-1, respectively. The following parameters were evaluated: 1) degree of neuromuscular block obtained by a combination of pancuronium + levobupivacaine and pancuronium + enantiomeric mixture; 2) efficacy of neostigmine and 4-aminopyridine in the reversal of neuromuscular block produced by drug combinations.

Results and Conclusion: Neostigmine and 4-aminopyridine were effective at reversing neuromuscular block obtained by different drug combinations, and the block was partially and totally reversed with neostigmine and 4-aminopyridine, respectively.