Comparison of alfentanil, fentanyl and sufentanil for total intravenous anaesthesia with propofol in patients undergoing coronary artery bypass surgery

We have studied the pharmacokinetics and pharmacodynamics of alfentanil, fe ntanyl and sufentanil together with propofol in patients undergoing coronar y artery bypass graft surgery (CABG). Sixty patients (age 40-73 yr, 56 male ) were assigned randomly to receive alfentanil, fentanyl or sufentanil and propofol. Plasma concentrations of these drugs and times for the plasma con centration to decrease by 50% (t(50)) and 80% (t(80)) after cessation of th e infusion were determined. Times were recorded to awakening and tracheal e xtubation. Total dose and plasma concentrations of propofol were similar in all groups. Mean total doses of alfentanil, fentanyl and sufentanil were 4 43, 45 and 4.4 mu g kg(-1), respectively. Time to awakening did not differ significantly. in patients receiving fentanyl, the trachea was extubated on average 2 h later than in those receiving sufentanil and 3 h rater than in those receiving alfentanil (P<0.05). The tao of fentanyl was longer (P<0.0 5) than that of alfentanil or sufentanil, and there was a linear correlatio n between the t(80) of the opioid and the time to tracheal extubation (r=0. 51; P<0.01). However, the t(50) values for these opioids were similar and d id not correlate with recovery time. In conclusion, patients undergoing CAB G and who were anaesthetized with fentanyl and propofol needed mechanical v entilatory support for a significantly longer time than those receiving alf entanil or sufentanil and propofol. On the basis of the interindividual var iation observed, the time to tracheal extubation was most predictable in pa tients receiving alfentanil and most variable in patients receiving fentany l, a finding which may be important if the patients are transferred to a st ep-down unit on the evening of the operation.