CLINICAL-STUDY OF INTERACTION BETWEEN ROCURONIUM AND SOME COMMONLY USED ANTIMICROBIAL AGENTS

The onset and duration of clinical relaxation and reversibility of roc uronium bromide (ORG 9426) 0.6 mg kg-1 were studied following administ ration of netilmicin 2 mg kg-1 (n=10) or cefuroxime 20 mg kg-1 (n=10) in patients undergoing urological surgery; and cefuroxime 20 mg kg-1 ( n=10) metronidazole 7.5 mg kg-1 (n=10), metronidazole 7.5 mg kg-1 and cefuroxime 20 mg kg-1 (n=10), or placebo (n=10) in patients undergoing abdominal surgery under anaesthesia with thiopentone, nitrous oxide i n oxygen, fentanyl and halothane. The antimicrobial agents were admini stered intravenously 5 min before rocuronium. Neuromuscular function w as monitored using mechanomyography and train-of-four (TOF) mode of st imulation. Onset of neuromuscular block occurred in approximately 60 s with all patients achieving complete block. The mean clinical duratio n (+/-SD) was 50+/-10.7 and 44+/-6.7 min following netilmicin and cefu roxime respectively in patients undergoing urological surgery; and 49/-13.7, 44+/-11.1, 48+/-11.1 and 38+/-7.3 min in the groups undergoing abdominal surgery receiving cefuroxime, metronidazole, cefuroxime and metronidazole combination and placebo respectively. There were no sta tistically significant differences between the groups in either the on set or the duration of clinical relaxation. Reversal of neuromuscular block with neostigmine carried out at spontaneous recovery of T1 (firs t response in the TOF) of 25% or more was easily achieved in all group s in 2-4 min. It is concluded that there is no significant interaction between rocuronium and single doses of the antimicrobial agents used in the present study.