A comparison of clinical and psychological effects of fentanyl and nalbuphine in ambulatory gynecologic patients.

Drug dosages, length of stay (LOS), and incidence of psychological side effects of fentanyl and nalbuphine were compared in a randomized, double-blind study using unpremedicated female day-surgery patients undergoing diagnostic laparoscopy. Patients received either fentanyl 1.5 micrograms/kg (F group; n = 142), low-dose nalbuphine 300 micrograms/kg (LN group; N = 103), or high-dose nalbuphine 500 micrograms/kg (HN group; n = 41), intravenously (IV) before anesthesia consisting of thiopental, N2O, O2, and a succinylcholine infusion. Additional IV intraoperative and IM postoperative opioids were given if required for signs of inadequate anesthesia or postoperative pain. The patients' clinical and psychological status was evaluated at 20-min intervals postoperatively by a team of trained interviewers. The low- and high-dose nalbuphine groups clinically resembled the fentanyl group in terms of dosing frequency and patients' self-ratings of postoperative analgesia. Length of stay and postoperative sedation were significantly greater with nalbuphine. The incidence of psychological side effects, including dreaming and postoperative anxiety, was also greater with nalbuphine. However, patient acceptance of nalbuphine was high and was similar to that observed in patients given fentanyl.