Immediate postoperative pain level from lumbar arthrodesis following epidural infiltration of morphine sulfate☆

OBJECTIVE To evaluate the pain level in patients treated with epidural infusion of morphine sulfate in a single dose, after a surgical procedure to perform lumber arthrodesis. METHODS Forty patients underwent posterolateral lumbar arthrodesis or intersomatic lumbar arthrodesis via a posterior route at one, two or three levels. They were prospectively randomized into two groups of 20. In the first group (study group), 2 mg of morphine sulfate diluted in 10 mL of physiological serum was infiltrated into the epidural space, through the laminectomy area. The second group (controls) did not receive analgesia. The patients were asked about their pain levels before and after the operation, using a visual analog scale (VAS). RESULTS It was found that the patients presented a significant diminution of pain as shown by the VAS. From before to after the operation, it decreased by an average of 4.7 points (p = 0.0001), which corresponded to 53.2% (p = 0.0001). CONCLUSION Application of 2 mg of morphine sulfate in a single epidural dose was shown to be a good technique for pain therapy following lumbar spinal surgery.