ROCURONIUM IN INFANTS, CHILDREN AND ADULTS DURING BALANCED ANESTHESIA

We studied 20 infants, 20 children arid 20 adults during balanced anae sthesia to compare the neuromuscular blocking effects of rocuronium in these age groups. Neuromuscular function was recorded by adductor pol licis emg and a cumulative log-probit dose-response curve of rocuroniu m was established. Thereafter, full spontaneous recovery of the neurom uscular function was recorded. Onset time of the first dose of rocuron ium was shorter in children than in infants or adults. The potency of rocuronium was greatest in infants and least in children; the ED, dose s (mean+/-SD) being 149 +/- 36 mu g . kg(-1) in infants, 205 +/- 52 mu g . kg(-1) in children and 169 +/- 47 mu g . kg(-1) in adults (P<0.05 between infants and children) and the ED(95) doses being 251 +/- 73 m u g . kg(-1), 409 +/- 71 mu g . kg(-1) and 350 +/- 77 mu g . kg(-1), r espectively (P<0.05 between all groups). The emg recovery following an average 94.5 +/- 4.8% neuromuscular blockade established by rocuroniu m was roughly similar in all study groups. Thus, one ED(95) dose of ro curonium, unlike vecuronium, acts as an intermediate-acting agent in a ll age groups.