EVALUATION OF FENTANYL AND SUFENTANIL ON THE DIAMETER OF THE COMMON BILE-DUCT BY ULTRASONOGRAPHY IN MAN - A DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY

Narcotic mu-agonists have been shown to increase the common bile duct pressure. With a recently introduced non-invasive ultrasonogaphic tech nique, we have demonstrated that morphine caused constriction of the c ommon bile duct. We have now investigated the effect of highly potent, widely used mu-agonists, fentanyl and sufentanil an the diameter of t he common bile duct using this technique in a double-blind, randomized study in 17 patients undergoing cholecystectomy. After premedication with midazolam and glycopyrrolate, anesthesia was induced by midazolam , 50 mu g.kg(-1) and thiopental, 3.0-5.0 mg.kg(-1). Tracheal intubatio n was facilitated by succinylcholine, 1.0 mg.kg(-1) and muscle relaxat ion maintained with vecuronium. Anesthesia was maintained with enflura ne or isoflurane and nitrous oxide in oxygen. The diameter of the comm on bile duct was determined before and at 4 and 8 minutes after the ad ministration of the study drugs. One way analysis of variance and pair ed t-test were used for statistical analysis. P < 0.05 was considered significant. No significant change in common bile duct diameter was ob served after i.v. placebo, nor were there any significant changes afte r fentanyl or sufentanil administration. Since the baseline common bil e duct diameters were not significantly different among the three grou ps, fentanyl or sufentanil in the doses used had no more effect than a placebo on common bile duct diameter. It is concluded that fentanyl a nd sufentanil caused no effect on the common bile duct, therefore, the se mu-agonists seem to be safe in patients in whom spasm of the common bile ducts should be avoided.