Additional droperidol, not butorphanol, augments epidural fentanyl analgesia following anorectal surgery

Study Objective: To examine the effects of additional droperidol or butorphanol to epidural fentanyl infusion on postsurgical analgesia.Design: Prospective, randomized, single blinded clinical study.Setting: University-affiliated medical center.Patients: 60 ASA physical status I and II patients undergoing anorectal surgery by one surgeon.Interventions: Patients were randomly allocated to the following groups according to the medication that was continuously administered into the epidural space: 1) Group C (n = 20) received 0.4 mg fentanyl in 40 ml of 0.125% bupivacaine; 2) Group D (n = 20) received 2.5 mg droperidol and 0.4 mg fentanyl in 40 ml of 0.125% bupivacaine; and 3) Group B (n = 20) received 2 mg butorphanol and 0.4 mg fentanyl in 40 ml of 0.125% bupivacaine over 24 hours postoperatively.Measurements and Main Result: Postsurgical analgesia and the incidence of fentanyl-related complications, such as nausea/vomiting, somnolence, pruritus, and respiratory depression, were assessed for 24 hours postoperatively. At 16 and 24 hours after surgery, 75% of patients in Group D reported no pain versus 35% in Group C (p < 0.05). In addition, the overall visual analogue scale examined at 24 hours was significantly lower in Group D than that in Group C (22 ± 17 mm vs. 44 ± 22 mm, respectively; p < 0.05). Simultaneously, the incidence of postoperative nausea/vomiting was lower in Group D compared with Group C (20% vs. 60%; p < 0.05). On the other hand, butorphanol did not modify the analgesic effects or complications of epidural fentanyl infusion.Conclusion: In this study population, additional droperidol, not butorphanol, improved postsurgical analgesia accompanied by less incidence of nausea/vomiting during epidural fentanyl administration.