Comparison of Intraoperative Infusion of Remifentanil Versus Fentanyl on Pain Management in Patients Undergoing Spine Surgery: A Double Blinded Randomized Clinical Trial

Background Remifentanil is an ultra-short-acting opioid which facilitates hemodynamic management. However, there are concerns about postoperative Remifentanil hyperalgesia because of its potent fast onset and offset. Objectives The aim of this study was to determine visual analog scale (VAS), postoperative pain, and morphine used in two groups after spine surgery. Methods In this randomized clinical trial study, 60 patients aged 18 - 60 years old, according to the American Society of Anesthesiology (ASA) I - II, who underwent spinal canal stenosis or scoliosis surgery, were divided into two groups. In the control group, patients received 0.07 - 0.1 µg/kg/h intraoperative Fentanyl infusion, and in the intervention group 0.1 - 0.2 µg/kg/min remifentanil was infused during the surgery. Both groups received 15 mg/kg intravenous Acetaminophen 20 minutes before the end of the surgery. Postoperative pain score and morphine consumption were measured 6, 12, 24, and 48 hours after discharge from the post-anesthesia care unit (PACU). Results During the first 12 hours, VAS and morphine consumption were significantly higher in remifentanil group (P < 0.001). However, no significant difference was found between the two groups in morphine consumption 12 - 48 hours after surgery. Conclusions These findings suggest that Remifentanil infusion during surgery may increase postoperative pain. Also, VAS and morphine consumption were higher during the first 12 hours.