Effects of alfentanil and fentanyl on common bile duct pressure.

The effects of alfentanil (7.5 or 15 micrograms/kg) and fentanyl (1.5 micrograms/kg) on common bile duct pressure were examined by using an indwelling postoperative T-tube in 36 conscious, unpremedicated patients. All opiate doses significantly (P less than 0.001) increased the pressure. There was no significant difference among the groups in the peak pressures nor in the times to peak pressures. Fentanyl had a significantly longer duration of effect on pressure.