Background and objectives: Attempts to reduce central sensitization after tissue injury have led to the concept of preemptive analgesia. The aim of this study was to evaluate the effect of spinal versus general anesthesia on postoperative pain and analgesic requirements in patients undergoing lower abdominal surgery.
Methods: Sixty women scheduled for lower abdominal surgery were randomly assigned to two groups of 30 patients each to receive spinal anesthesia (SA) or general anesthesia (GA). In the SA group, 3 mL of hyperbaric 0.5% bupivacaine was injected into the subarachnoid space through the third or fourth lumbar interspace. In the GA group, anesthesia was maintained with isoflurane and nitrous oxide. Postoperative pain was assessed for 48 hours by a visual analog scale of pain at rest and during cough and by patient-controlled cumulative morphine doses.
Results: The pain score at rest was significantly lower in the SA group than in the GA group 6-24 hours after surgery. The cough-associated pain score was also lower in the SA group than in the GA group at 6-30 hours after surgery. Furthermore, the SA group consumed less patient-controlled morphine than did the GA group within the first 24 postoperative hours.
Conclusion: Postoperative pain after lower abdominal surgery can be significantly decreased if the surgery is performed with use of SA.