Recovery of respiration after neuromuscular blockade with alcuronium

Alcuronium 0.2 mg kg-1 was given to six patients to investigate the simultaneous recovery of breathing and peripheral neuromuscular function. Anaesthesia was maintained with 66% nitrous oxide in oxygen supplemented with 0.5% halothane, and the patients were ventilated to normocarbia. Patients were disconnected from the ventilator after the reappearance of the tetanic response. This response returned at a mean time of 19.2 min after the injection of alcuronium and oxygenation was maintained thereafter by means of apnoeic diffusion. Spontaneous breathing returned at a mean time of 23.6 min after the injection of alcuronium. Sixty minutes after the administration of alcuronium, respiratory exchange was judged adequate, and at that time neuromuscular function was still markedly depressed with a tetanic height less than 25% of control. It was concluded that, because of the slow recovery of neuromuscular function, alcuronium should be reserved for the longer surgical procedure.