Is intentional unilateral epidural catheterization reliable on pain management?

Abstract

Aims: In this study we aimed to compare the efficacy of intentionally directed catheter towards the operative side with midline approach and two different doses of morphine for postoperative pain relief in unilateral epidural catheterization. Method: After obtaining approval of the ethical committee and written informed consent, 36 patients aged 18–65 years, with ASA physical status I-II, scheduled for elective open reduction and osteosynthesis for malleolar fracture were included in this study. The patients were randomly divided into three groups. A Tuohy needle was advanced at a 5° to 10° angle from midline and then the bevel of the needle was rotated 90° towards the operative side in Group I and Group II. In Group III, the needle was advanced by midline approach. An epidural catheter was inserted and 4 ml of 2% lidocaine was injected through the catheter as a test dose. 20 min later, 2 mg morphine in Groups I and III and 1 mg of morphine in Group II were administered through the catheter. The infusion started with 0.2 mg hr−1 in all groups with an epidural patient controlled analgesia device. Cardiorespiratory variables and pain scores were assessed postoperatively. Side effects of morphine, total morphine consumption, the number of the incremental doses asked and received were recorded postoperatively. Statistical analysis was performed by analysis of variance, paired t-test, and chi-squared test. Results: Total morphine consumption and incidence of urinary retention were lower in Group II than in Groups I and III (p ≤ 0.01). Conclusion: Our study shows that unilateral epidural catheterization with 1 mg morphine produces adequate analgesia for postoperative pain and also reduces side effects of epidural morphine.