Prospective comparative study of the effectiveness of epidural morphine and ropivacaine for management of pain after spinal operations

Summary.

 Objective: Evaluation of the effectiveness of local application of morphine or ropivacaine for treatment of local and radicular pain after lumbar disc operations. Critical review of the literature about the possibilities of management of postoperative pain after spinal operations.

 Methods: A total of 113 patients were randomly given 5 mg morphine sulfate (N=42), 10 ml 0,25% ropivacaine (N=42) or physiological NaCl solution (N=21) locally after lumbar disc operation before wound closure. Postoperative lumbar and radicular pain was scored by the patients from 0 to 10 and registered on the evening of the day of operation and on the 1., 2., 3., and 5. days. Mean pain numbers of the 3 groups have been compared, subdivided into local lumbar and in radicular pain. Our own results have been compared with the results of reports in the literature.

 Results: In our own study the morphine group had less lumbar and less radicular pain on all 5 days than both of the two other groups. This difference was statistically significant on days 0, 1, 2, and 3. The ropivacaine group was on all days less effective than the morphine group, better than the placebo group on the operation and first day, but the difference against the placebo group was statistically not significant.

 Conclusion: Local application of 5 mg morphine sulfate is effective in prevention or reduction of postoperative lumbar and radicular pain after lumbar disc operations. Ropivacain is less effective. The routine application of epidural morphine at the end of spinal operations can be recommended. It also can be justified to try to prolong the morphine effect by mixing it into a paste as described by Needham and by Hurlbert, and to irrigate the operative field with ropivacaine at the end of the operation.