Comparative Evaluation of Pregabalin and Clonidine as Preemptive Analgesics for the Attenuation of Postoperative Pain Following Thoracolumbar Spine Surgery

STUDY DESIGN: Prospective, randomized, double blind, placebo-controlled study. PURPOSE: To compare clonidine and pregabalin with placebo for the attenuation of postoperative pain after thoracolumbar spinal surgery and instrumentation OVERVIEW OF LITERATURE: Spine surgery is associated with moderate to severe postoperative pain that needs to be controlled to improve patient’s outcome. Alpha 2 agonists (e.g., clonidine) and gabapentenoids (e.g., pregabalin) are successfully used as part of a multimodal analgesic regimen. METHODS: Total 75 patients were enrolled and randomly allocated into three groups. Group P received pregabalin (150 mg), group C received clonidine (150 mcg), and group N received placebo 90 minutes preoperatively. A standard anesthesia protocol comprising fentanyl, thiopentone, vecuronium, nitrous oxide, and oxygen in isoflurane was used for all patients. Postoperative recovery profile, pain, time for first analgesic, 24-hour analgesic requirement, sedation, and hemodynamic parameters were noted. RESULTS: Recovery profile was similar in all three groups; however, the patients in group P and C were more sedated (p<0.05). Group N patients had a higher Visual Analog Scale (VAS) score (p<0.05) and the time for first analgesic was also lower (p=0.02). Postoperative (24-hour) analgesic requirement was maximum in group N, followed by that in group C and group P. The VAS score was highest in the control group; however, after 12 hours, it was similar in all groups. CONCLUSIONS: Postoperative pain and analgesic requirement is significantly attenuated by preoperative administration of a single dose of clonidine (150 mcg) or pregabalin (150 mg); pregabalin was more effective. Thus, their use offers a reasonable strategy for pain management in patients undergoing spine surgery.