Comparison of Remifentanil and Fentanyl for Postoperative Pain Control after Abdominal Hysterectomy

PURPOSE: In this randomized, double-blind study, we investigated the analgesic efficacy and side effects of continuous constant-dose infusions of remifentanil after total abdominal hysterectomy and compared it to fentanyl. MATERIALS AND METHODS: Fifty-six adult female patients scheduled for elective total abdominal hysterectomy were enrolled in this study. Patients were randomly assigned to two groups according to fentanyl (group F, n = 28) or remifentanil (group R, n = 28) for postoperative analgesia. Patients in group F were given fentanyl intravenously with an infusion rate of fentanyl 0.5 µg/kg/hr; group R was given remifentanil with an infusion rate of remifentanil 0.05 µg/kg/min for 2 days. Pain intensity at rest, occurrence of postoperative nausea and vomiting (PONV), dizziness, pruritus, and respiratory depression were assessed 1 hr after arrival at the post-anesthesia care unit, at 6; 12; 24; and 48 hr postoperation and 6 hr post-infusion of the study drug. Pain was evaluated by using visual analogue scale (VAS; 0 - 10). The time that patients first requested analgesics was recorded as well as additional analgesics and antiemetics. RESULTS: There were no significant differences in VAS, time to first postoperative analgesics, and additional analgesics between the 2 groups. The incidences and severities of PONV and opioid related side effects were not different between the groups; however, there were 3 episodes (10.7%) of serious respiratory depression in group R. CONCLUSION: Continuous infusion technique of remifentanil did not reveal any benefits compared to fentanyl. Furthermore, it is not safe for postoperative analgesia in the general ward.