The comparative effect of single dose mivacurium during sevoflurane or propofol anesthesia in children.

Background: We aimed to randomly compare intubating conditions, recovery characteristics and neuromuscular effects of single dose of mivacurium (0.2 mg.kg(-1)) during sevoflurane vs. propofol anesthesia in 60 healthy children, undergoing inguinal surgery.

Methods: All children were randomly allocated to receive 2 mg.kg(-1) propofol iv or sevoflurane 8% inspired concentration for induction of anesthesia. Anaesthesia was maintained with 66% nitrous oxide in oxygen and 100-120 microg.kg(-1) propofol or sevoflurane approximately 2-3% inspired concentration with controlled ventilation. The ulnar nerve was stimulated at the wrist by a train-of four (TOF) stimulus every 20 s and neuromuscular function was measured at the adductor pollicis. When the response to TOF was stable, 0.2 mg.kg(-1) mivacurium was given. The trachea was intubated successfully at the first attempt in all patients.

Results: Onset time following a single dose of mivacurium was shorter in the sevoflurane group (2.99 min), than in the propofol group (4.42 min). The times to 25, 50, 75, and 90% recovery were significantly longer in the sevoflurane group (13.1, 15.7, 18.6, and 21.2 min, respectively) than in the propofol group (11.4, 13.2, 14.4, and 17.2 min respectively). TOF ratios of 50, 70, and 90% were significantly occurred later in sevoflurane group than propofol group.

Conclusions: Our results indicate that when compared with propofol group, the sevoflurane group had an accelerated onset and a delayed recovery of neuromuscular block induced by mivacurium in children.