경막외 Naloxone 투여가 경막외 Sufentanil에 의한 가려움증에 미치는 영향

Background: Postoperative pruritus following the administration of epidural narcotics is a very common and undesirable side effect. Therefore, we evaluated the use of a combination of naloxone and sufentanil via patient controlled epidural analgesia to determine if the incidence of pruritus was decreased when compared to the use of sufentanil alone. Methods: Patients scheduled for subtotal gastrectomy under general anesthesia were enrolled in a prospective, double-blinded and randomized trial. All patients received a $20{\mu}g$ epidural bolus of sufentanil in 5 ml of 0.2% ropivacaine. Following administration of the epidural, patients in the sufentanyl group (S) received a continuous epidural comprised of sufentanil ($0.75{\mu}g/ml$) in 0.2% ropivacaine, whereas patients in the naloxone group (N) received an epidural infusion comprised of naloxone ($4{\mu}g/ml$) and sufentanil ($0.75{\mu}g/ml$) in 0.2% ropivacaine. The infusion rate, demand dose and lockout interval were 5 ml/hr, 0.5 ml and 15 minutes respectively. Next, the occurrence of postoperative analgesia and side effects were evaluated by blinded observers. Results: The incidence of pruritus (47.4% versus 20.0%, P = 0.013) and nausea (42 .1 % versus 20.0%, P = 0.043) were lower in group N than in group S. In addition, there were no significant differences observed in the visual analogue scale, the incidence of vomiting or the incidence of sedation. Furthermore, epidural infusion of naloxone at $0.25-0.4{\mu}g/kg/hr$ did not affect the requirement for postoperative sufentanil. Conclusions: Epidural naloxone reduces epidural sufentanil induced pruritus and nausea without reversing its analgesic effects.