[Antagonism to neuromuscular effect of subcutaneous administration of pancuronium by neostigmine].

It has been reported that subcutaneous administration of pancuronium produces prolonged neuromuscular blockade. The purpose of this study was to evaluate the antagonistic effect of neostigmine on neuromuscular blockade following subcutaneous injection of pancuronium in anesthetized patients. Fourteen male patients aged 32-67 yr, weighing 50-58 kg, and scheduled for surgical operation lasting more than 6 hr were included in the study. None of the patients had paresis. Anesthesia was induced with thiamylal and SCC. Patients under N2O-oxygen-enflurane (1.0-1.5%) anesthesia, were divided into two groups (n = 7 in each group). Group A was given an intravenous bolus of pancuronium 6 mg. Group B received pancuronium 6 mg subcutaneously in the ankle. Train-of-four responses were evaluated every 12s by measuring the force of thumb adduction produced in response to supramaximal stimulation of the ulnar nerve at the wrist. When the train-of-four ratios recovered to approximately 0.2 in groups A and B, a mixture of neostigmine 1.0 mg and atropine 0.5 mg was administered. The onset of fade in train-of-four responses was significantly more rapid in group A (intravenous administration) than in group B (subcutaneous administration). Time intervals to maximum train-of-four depression from pancuronium administration in groups A and B averaged 2.6 and 125.4 min, respectively. No significant differences in the recovery times of the train-of-four ratios from 0.2 to 0.7 following neostigmine administration in groups A and B were demonstrated. None of the patients who received pancuronium subcutaneously showed recurarization following neostigmine administration.(ABSTRACT TRUNCATED AT 250 WORDS)