The effects of adding sufentanil to bupivacaine for postoperative patient-controlled epidural analgesia

We tested the hypothesis that postoperative patient-controlled epidural analgesia was more effective with the combination of sufentanil and bupivacaine (Group 2) than with bupivacaine alone (Group 1). One hundred patients undergoing thoracic, upper abdominal, and aortic surgery were provided with an epidural catheter and randomly allocated to one of the two groups. Postoperatively, patients were monitored in a postanesthetic care unit for at least 1 day before they were transferred to a ward. Both groups had similar demographics and operations. Pain treatment was continued for 4.4 +/- 0.6 and 4.5 +/- 0.7 days for Groups 1 and 2, respectively. Although Group 2 patients needed less volume of the epidural analgesics on Postoperative Days 1 and 2, they reported lower pain intensity at rest and during activity for the first three postoperative days. The groups did not differ from each other regarding the incidence of respiratory depression. There was no late respiratory depression; however, three cases of early respiratory depression were detected and easily treated (Group 1 one event, Group 2 two events). Motor block was only seen in patients with lumbar epidural catheters. There was no difference between groups, and all patients with thoracic catheters could be mobilized beginning on the first postoperative day. We conclude that 1) the addition of sufentanil to a small-dose bupivacaine augments epidural analgesia and 2) thoracic epidural catheters should be used for postoperative analgesia after abdominal or thoracic surgery.