BACKGROUND: Sevoflurane has been reported to potentiate the effect of rocuronium. We compared the effect of sevoflurane and propofol on intubating conditions and their corresponding hemodynamic changes, and also compared the intubation conditions at different intubation timing using the rocuronium.

METHODS: Sixty patients were randomized into four groups: group P (P-60, P-90) received 10 mg/kg/hr of propofol after 2 mg/kg of bolus injection; group S (S-60, S-90) were inhaled with 8 vol% sevoflurane after injection of 50 mg of thiopental sodium. Intubation was attempted at either 60 seconds (P-60, S-60) or 90 seconds (P-90, S-90) after the rocuronium administration. Intubation conditions were assessed and evaluated as excellent, good, poor and inadequate. Single twitch responses were measured at every 30 seconds after rocuronium administration. Blood pressure and heart rate were measured before induction, before intubation and immediately after intubation.

RESULTS: Excellent and good intubation conditions were obtained in 60% (n = 9) of group P-60, 73% (n = 11) of group S-60, 92% (n = 14) of group P-90 and 100% (n = 15) of group S-90. Single twitch responses were fewer in group P-90 and S-90 compared to those in group P-60 and S-60 (P < 0.01). Blood pressure and heart rate after intubation were elevated in all four groups.

CONCLUSIONS: Intubation conditions were not significantly different between inhalation of sevoflurane and intravenous administration of propofol when using rocuronium. Prolonged interval between rocuronium administration and intubation resulted in improved intubation conditions.