[Rapid onset of the action of vecuronium by administration of a precurarizing dose]

The administration of vecuronium in divided doses with respect to onset of action and intubating conditions was investigated. This study was conducted in 3 parts. In part 1 the maximal precurarizing dose of 0.015 mg/kg vecuronium was found. In the second part we showed that the optimal time interval between divided doses was 3 min. In the third part we made a comparative investigation between the effect of 0.015 + 0.085 mg/kg body wt. at a 3 min interval and that of a single dose of 0.1 mg/kg body wt. vecuronium. --Neuromuscular function was assessed in semiquantitative manner, using the train of four (TOF) stimulation of ulnar nerve. Administration of vecuronium in divided doses, compared with a single dose of 0.1 mg/kg body wt., resulted in a more than 1 min earlier onset time of 1.5-2.5 min and facilitated early intubation. As soon as twitch tension had completely disappeared uniform by excellent intubating conditions were available in all cases. The administration of vecuronium in divided doses enabled better intubating conditions than the same single dose of vecuronium.