OBJECTIVETo compare the effects of sevoflurane and propofol-remifentanil anesthesia on neuromuscular blockade produced by continuous cisatracurium infusion.

METHODSForty ASA I or II patients undergoing selective surgery were randomly divided into sevoflurane and propofol-remifentanil anesthesia groups (n=20). Neuromuscular blockade was monitored using train-of-four (TOF) stimulation by recording the contraction force of the adductor pollicis muscle with a muscle relaxation monitor. A bolus dose of cisatracurium of 0.15 mg/kg was administered to facilitate endotracheal intubation, followed by continuous infusion adjusted manually to maintain the first twitch (T1) < or = 5% of the control level. The following variables were recorded including the infusion rate, total amount of cisatracurium, spontaneous recovery index (RI), and the time interval from termination of infusion cisatracurium to recovery of TOF ratio (TOFR) to 0.9.

RESULTSWith the maintenance of a 95%-99% neuromuscular blockade, the infusion rate was significantly lower in sevoflurane group than in propofol-remifentanil group (P<0.05), and stabilized in both groups after 120 min. No significant differences were found in RI or the time to TOFR of 0.9 between the two groups (P>0.05).

CONCLUSIONDuring the maintenance of stable neuromuscular blockade by continuous cisatracurium infusion, both sevoflurane and propofol-remifentanil anesthesia can time-dependently enhance the effect of cisatracurium without producing significant differences in the recovery properties.