[Neuromuscular blocking effects of Org 9426 (rocuronium bromide); a comparative study with vecuronium bromide in Japanese patients]

Background: Efficacy and safety of Org 9426 were compared with those of vecuronium bromide in Japanese patients.

Methods: We studied 88 Japanese patients undergoing surgery requiring general anesthesia. Patients were allocated randomly to receive intubation dose of 0.6 mg x kg(-1), 0.9 mg x kg(-1) of Org 9426 or 0.1mg x kg(-1) of vecuronium. Following an intubation dose, patients received maintenance doses of 0.1, 0.15 or 0.2 mg x kg(-1) of Org 9426 or 0.025 mg x kg(-1) of vecuronium. The neuromuscular block was monitored with acceleromyography using TOF stimuli. Sevoflurane was administered to all treatment groups after intubation.

Results: The onset times of the 0.6 and 0.9 mg x kg(-1) of Org 9426 groups were 84.6 and 77.1 sec respectively, which showed statistical difference between the onset time of 0.1 mg x kg(-1) of vecuronium, 125.7 sec. The intubation condition was similar among three treatment groups. The clinical durations of 0.6 and 0.9 mg x kg(-1) of Org 9426 and 0.1 mg x kg(-1) of vecuronium were 53.4, 73.4 and 59.9 min, respectively. Clinical duration and spontaneous recovery time of maintenance dose of 0.15 mg x kg(-1) of Org 9426 were similar to those of 0.025 mg x kg(-1) of vecuronium.

Conclusions: Org 9426 showed more rapid onset time than that of vecuronium and similar clinical duration and recovery times to those of vecuronium in Japanese patients.