A prospective randomized trial comparing epidural morphine through intraoperatively placed epidural catheter and intravenous morphine in major lumbar spinal surgery.

Study Design: A randomized, controlled trial.

Objective: To compare the efficacy of pain control and complications between patients utilizing continuous infusion epidural morphine versus intravenous morphine in posterior spinal surgery.

Summary Of Background Data: Recently, there has been increased interest in the use of epidural infusion analgesia for spinal surgery. By simply placing the tip of catheter at the level of operation before the wound closure, a continuous infusion of local anesthetics is directly delivered into the epidural space. Techniques used in the literature vary as per analgesic agents, number of catheters, and the infusion method. Few are the randomized control studies.

Methods: A total of 120 patients, who had posterior spinal operations, were randomly assigned to receive either continuous epidural infusion morphine, continuous epidural infusion morphine with Bupivacaine, or intravenous morphine as a postoperative analgesia. Visual analogue Pain scale (Pain VAS) was evaluated every 4 hours the first day, and at 36 and 48 hours postoperatively. Additional doses of intravenous Nalbuphine hydrochloride, complications, and the satisfaction score were recorded.

Results: Baseline characteristics of the 3 groups were similar. The mean Pain VAS in the epidural morphine group (groups 1 and 2) were less than that of group 3 at all times up to 48 hours postoperatively (P<0.05). Pain VAS for group 1 was more than that of group 2 at the 16- and 24-hour marks (P<0.05). Pruritus was a common complication in the epidural morphine group. There was no respiratory depression in this study. Patients in groups 1 and 2 had a high proportion of excellent and very good satisfaction (70% to 80%).

Conclusion: Epidural infusion analgesia is safe and effective for posterior spinal surgery.