Abstract
Vecuronium has been developed as a more rapidly acting, non-depolarizing, steroidal, neuromuscular blocking agent. Onset time of neuromuscular blockade was measured for increasing doses of vecuronium in 163 patients (ASA class I-II), between 20 and 60 years of age, who had elective surgical procedures. Vecuronium was continuously quantitated by recording the EMG response to stimulation of the ulnar nerve by train of four. Each patients was assigned to one of nine groups to recieve 0.07, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45 mg·kg-1 of vecuronium. Intubation was performed when the blockade was maximum. Intubation could be satisfactorily carried out in the 0.15 mg·kg-1 dose group. The onset time from the time of vecuronium administration to maximum blockade decreased from 287.5±74.1 to 140.9±25.1 sec when the vecuronium doses increased from 0.07 to 0.2mg·kg-1. Increasing the dose above 0.2mg·kg-1 did not appreciably shorten the time to full neuromuscular blockade. The duration of action of vecuronium from the time of injection to 15% recovery was longer with lager doses, up to a limit of 0.3mg·kg-1. The optimal dose of vecuronium for endotracheal intubation was estimated to be 0.15-0.2mg·kg-1. In the present study there was no obvious side effect associated with the administration of a large dose of vecuronium.
