Postoperative analgesia in herniated disk surgery. Comparative study of diclofenac , lysine acetylsalicylate, and ketorolac

INTRODUCTION: Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in treating musculoskeletal pain and are theoretically ideal for treating postoperative pain of the lumbar column. OBJECTIVES: To compare the analgesic efficacy and side effects of treatment with 3 NSAIDs (lysine acetylsalicylate, ketorolac and diclofenac) in the treatment of pain after surgery for lumbar disc hernia. PATIENTS AND METHODS: We enrolled 75 ASA I-II patients undergoing discectomy because of lumbar disc hernia; balanced general anesthesia was used in all cases. The patients were randomly distributed in 3 groups based on type of analgesia given in the immediate postoperative period. Group A received lysine acetylsalicylate (1800 mg), group B received ketorolac (30 mg) and group C received diclofenac (75 mg). The analgesics were diluted in 100 mg of saline solution and administered through a peripheral vein over 10 min. We evaluated the analgesia attained on a visual analog scale (VAS) and the physiological response to pain was assessed by monitoring changes in arterial pressure, heart rate and breathing frequency. If analgesia was insufficient 30 min after administration of the drug, 200 mg of lysine cloximate was given as a top-up. The side effects of each drug were also recorded. RESULTS: VAS evaluation showed significant reductions in pain 60 min after administration in groups A and B and after 120 min in group C. Nine patients in each group required lysine cloximate. There were no significant differences in physiological response among the 3 groups. No patient suffered major side effects. Mild side effects were reported most often in group B. CONCLUSIONS: The NSAIDs studied were inadequately for treating pain after surgery for lumbar disc hernia. Ketorolac was no better than the other analgesics studied but was associated with a higher number of mild side effects.