Comparison of ocfentanil and fentanyl as supplements to general anesthesia

Three doses of ocfentanil (1, 3, and 5 micrograms/kg), a new narcotic, were compared with fentanyl (5 micrograms/kg) as a supplement to general anesthesia. Sixty adult ASA I-III patients undergoing elective surgery were studied. The drugs were given as a bolus injection during induction of anesthesia in a double-blind manner. With the stimulus of tracheal intubation, systolic arterial blood pressure increased (mean +/- SE) from 127 +/- 6.9 to 183 +/- 7.4 mm Hg and heart rate increased from 82.1 +/- 4.8 to 104 +/- 6.4 beats/min in patients who had received 1 microgram/kg of ocfentanil intravenously. In comparison to patients who received 1 microgram/kg of ocfentanil, the increases in heart rate and systolic arterial blood pressure at the time of tracheal intubation were less with 3 and 5 micrograms/kg of ocfentanil and 5 micrograms/kg of fentanyl (P less than 0.05). At incision, heart rate decreased after the intravenous administration of 5 micrograms/kg of ocfentanil when compared with patients who received 1 microgram/kg of ocfentanil. There were differences between study groups in the mild increase in arterial blood pressure observed at incision. The authors conclude that ocfentanil and fentanyl appear to be similar in action, with 3 micrograms/kg of ocfentanil being approximately equivalent in effect to 5 micrograms/kg of fentanyl.