BACKGROUND: Sevoflurane is the most recently available volatile agent which permits the rapid induction with its nonirritant nature. The goal of this study was to compare the hemodynamic responses of sevoflurane induction and maintenance period with those of fentanyl-midazolam/isoflurane anesthesia for CABG. METHODS: Twenty-eight patients who underwent CABG were given anesthesia, and were randomly assigned to receive sevoflurane (Sevo Group, n = 15) or fentanyl-midazolam/isoflurane (Iso-Fent Group, n = 13), as induction and maintenance agents. In the Sevo group, anesthesia was induced with two or three deep breaths of 7.5% sevoflurane, and maintained with 2% sevoflurane after intubation. The Iso-Fent Group received fentanyl 5microgram/kg and midazolam 0.2 mg/kg with oxygen for induction and maintained with 0.8% isoflurane and 5microgram/kg/hr of fentanyl by infusion. All were given vecuronium as a muscle relaxant. Cardiac and oxygen metabolic profiles were measured before and 10 minutes after tracheal intubation. RESULTS: Before induction, there was no difference between Sevo and Iso-Fent group in terms of cardiac and oxygen metabolic profiles. After intubation, mean arterial pressure, mean pulmonary arterial pressure, pulmonary capillary wedge pressure, heart rate and mixed venous oxygen saturation in the Sevo group were higher than in the Iso-Fent group (P < 0.05). The ST-segment changes in the EKG monitoring was unremarkable during anesthesia induction in either group. CONCLUSIONS: For the induction and early anesthesia maintenance in patients undergoing CABG surgery, sevoflurane may be a substitute for fentanyl-midazolam/isoflurane without any significant hemodynamic changes.