NEOSTIGMINE REVERSAL OF VECURONIUM NEUROMUSCULAR BLOCK AND THE INFLUENCE OF RENAL-FAILURE

The duration of clinical relaxation induced by vecuronium and reversal by neostigmine was studied in 40 patients with renal failure (RF) and 40 patients with normal renal function (NL) under general anesthesia. Patients were premedicated with flunitrazepam, and anesthesia commenc ed with fentanyl 1-2 mu g/kg, thiopental 5-8 mg/kg, and vecuronium 0.1 mg/kg. Anesthesia was maintained with 60% nitrous oxide in oxygen, is oflurane 0.3%-1.0% end-tidal concentration, and 1 mu g/kg fentanyl eve ry 20-30 min. Neuromuscular block was reversed by the administration o f intravenous neostigmine 40 mg/kg at the time of reappearance of eith er two or four responses to the train-of-four (TOF) stimulation. Monit oring of neuromuscular function consisted of supramaximal TOF stimulat ion of the ulnar nerve and the evoked thumb response was registered us ing a force transducer. Spontaneous recovery time, reversal time, and the time to recovery of TOF ratio to 0.7 were recorded. RF did not pro long the vecuronium neuromuscular blocking effect, reversal was achiev ed at the same rate in NL as in RF, and the duration of reversal of ne uromuscular blocking effect of vecuronium was not influenced by the ti me of administration of neostigmine. Therefore, the neuromuscular bloc king effect of a tracheal intubating dose of vecuronium can be reverse d at the same rate in patients with end-stage RF as in patients with n ormal kidney function.