Single Dose Preemptive Amitriptyline Reduces Postoperative Neuropathic Pain After Lumbar Laminectomy and Discectomy A Randomized Placebo-controlled Clinical Trial

Abstract

Background: Ongoing neuropathic pain is a common problem in patients undergoing lumbar discectomy. Central sensitization is believed to be the main cause of maintained neuropathic pain after discectomies. Tricyclic antidepressants are known as the drug of choice for neuropathies; however their acute role is a matter of controversy. The aim of this study is to assess the acute role of amitriptyline to reduce postoperative pain and opioid consumption in single level lumbar discectomies. Methods: Over 1 year, patients with a decision for single level lumbar laminectomy and discectomy were randomly assigned into groups A and B, each received similar capsules containing amitriptyline or matching placebo 2 hours before surgery. Same anesthetic protocol was performed. Only patients with postoperative leg pain remained in the study. Visual analog scale and morphine consumption were recorded at 6 hours intervals up to 24 hours. The results were analyzed by SPSS V.13 and chi(2) and t test were used as the statistical tests. Finally, the groups were revealed: "A'' was amitriptyline and "B'' was the placebo group. Results: Pain was significantly reduced in each group at each time intervals (P < 0.001). The amitriptyline group had a significantly lower pain score by the end of 24 hours (P = 0.047), whereas morphine consumption was not different statistically. Conclusions: Preemptive amitriptyline is effective to reduce remained neuropathic pain after lumbar discectomies. The treatment of neuropathic pain should be considered before the surgery.