BACKGROUND: Remifentanil appears to have a pharmacologic profile similar to other potent mu agonists, but with exceptionally short lasting pharmacokinetics. It is likely to make it a very useful opioid for clinical practice. The bispectral index (BIS) has been used as an indicator of sedative state and has been considered to be related to anesthetic agents and noxious stimulus. The purpose of this study is to compare sedative and cardiovascular effects of remifentanil and fentanyl during target controlled infusion (TCI) of propofol by monitoring BIS and hemodynamics.

METHODS: Fifty-two patients undergoing total abdominal hysterectomy were randomly assigned to remifentanil group and fentanyl group with 26 cases in each group. Anesthesia was induced with propofol (4µgram/ml) and either remifentanil (0.5µgram/kg) or fentanyl (1.5µgram/kg) and was maintained with inhalation of 50% nitrous oxide and 50% oxygen mixture and a continuous infusion of either remifentanil (0.2µgram/kg/min) or fentanyl (0.03µgram/kg/min). Depth of anesthesia, hemodynamic changes and adverse reactions were observed.

RESULTS: The number of patients exhibited light depth of anesthesia during tracheal intubation and maintenance in the remifentanil group was significantly lesser than that in the fentanyl group (P<0.05). During intubation, skin incision, maintenance of anesthesia and extubation, remifentanil group shows lesser fluctuation of hemodynamic value than those in the fentanyl group (P<0.05). BIS was significantly decreased both groups during infusion of propofol, but no difference was found between the two groups. There was no significant difference between the two groups in the aspect of adverse reactions.

CONCLUSIONS: Remifentanil with propofol TCI based anesthetic can prevent the fluctuation of heart rate and mean arterial pressure during the operation especially, during intubation.