Postoperative analgesia after lumbar laminectomy: Epidural fentanyl infusion versus patient-controlled intravenous morphine

We compared the efficacy and safety of continuous epidural fentanyl infusion with intravenous morphine via a patient-controlled analgesia system (IV-PCA) in the management of postoperative pain after lumbar laminectomy. Twenty patients undergoing elective lumbar laminectomy were randomly allocated to one of two groups. The epidural group (n = 10) received an epidural fentanyl infusion (2 μg/mL at 4-10 mL/h) while the IV-PCA group (n = 10) received IV morphine through a PCA system. The general anesthetic technique was standardized. Visual analog pain scores were recorded at 12, 24, and 48 h after the operation. The amount of morphine (or its equivalent in fentanyl) used over the 48-h postoperative period was documented. The postoperative pain scores were significantly lower in the epidural group than in the IV-PCA group throughout the study period. The total consumption of morphine (or its fentanyl equivalent) over the 48-h period was significantly lower (P < 0.001) in the epidural group compared to the IV-PCA group. Although more patients in the IV-PCA group required urinary catheterization and had somnolence than the epidural group, there was no difference in the incidence of vomiting or pruritus. No patient developed respiratory depression or wound infection. We conclude that continuous epidural infusion of fentanyl is superior to IV-PCA morphine in the management of pain after lumbar laminectomy.