[A randomized double-blind comparison of epidural versus intravenous tramadol infusion for postoperative analgesia]

This study compared epidural and intravenous tramadol infusions for postoperative analgesia after gastrectomy.

Twenty patients were assigned randomly to receive either tramadol epidurally and saline intravenously (group-E) or tramadol intravenously and saline, epidurally (group-I) in a double-blind fashion. At the end of the operation, each patient received a bolus of tramadol 2 mg x kg(-1) either epidurally or intravenously and 7 mg x kg(-1) x day(-1) tramadol infusion was begun via the same route. Concurrently, a saline bolus and its infusion were given via the alternate route.

Both groups obtained adequate pain relief and there was no difference between the groups in pain score. But one patient in E-group was excluded from the study for respiratory depression 8 hours after the operation. No other side effects were detected in either group except mild nausea.

We conclude that intravenous tramadol infusion provides effective and safe postoperative analgesia. A futher examination is required for the suitable dose of tramadol in epidural infusion.