en Spine Research <strong>Background and Aim:</strong> In lumbar spine fusion surgeries, spinal anesthesia (SA) can enhance comfort and reduce postoperative pain compared to general anesthesia (GA). This study aimed to compare the preoperative and postoperative outcomes of the two approaches, given their unique advantages and disadvantages.<br> <strong>Methods and Materials/Patients:</strong> This randomized, single-blind clinical trial involved 48 patients aged 18-65, classified as American society of anesthesiologists (ASA) I or II, who were candidates for spinal fusion surgery. Participants were divided into two groups: General and spinal anesthesia (GSA, n=24) and GA (n=24). The primary outcome was hemodynamic changes, while the secondary outcomes focused on pain intensity and side effects, such as postoperative nausea, vomiting, and shivering. The key variables included vital signs, intraoperative blood loss, propofol and midazolam doses, and surgical duration from operating room entry to discharge from recovery.<br> <strong>Results:</strong> No significant differences in demographics or medical history were observed between the groups. The operative time was shorter in the GSA group (P=0.048). No notable differences were observed in terms of bleeding, nausea/vomiting, or shivering between the two methods. However, the median postoperative heart rate was significantly lower in the GSA group (P=0.007), and pain levels were also significantly reduced in both groups, with lower scores observed in the GSA group compared to GA (P=0.005). Hemoglobin levels decreased in both groups post-surgery (P<0.001). Repeated-measures analysis of variance (ANOVA) indicated significant effects on blood pressure, with GSA consistently showing lower readings than GA throughout the observation period.<br> <strong>Conclusion:</strong> Evidence from clinical trials indicates that combining GSA leads to shorter operative times, improved postoperative cardiac regulation, more stable intraoperative blood pressure, and better immediate pain control. These benefits promote the use of spinal anesthetic adjuvants in suitable surgical groups, ensuring hemodynamic stability without affecting recovery time or increasing bleeding risk. These findings are crucial for enhancing anesthetic practices and optimizing patient outcomes. Lumbar spine, Fusion surgery, Postoperative pain, General anesthesia, Spinal anesthesia Hemodynamic 0 0 http://irjns.org/browse.php?a_code=A-10-1352-1&slc_lang=en&sid=1 Afshin Mardvar 100319475328460012564 0009-0009-9915-9743 Yes Department of Neurosurgery, School of Medicine, Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran. Zoheir Reihanian zoheir.reihanian@gmail.com 100319475328460012566 100319475328460012566 No Department of Neurosurgery, School of Medicine, Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran. Seifollah Jafari 100319475328460012567 100319475328460012567 No Department of Neurosurgery, School of Medicine, Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran. Morteza Modaenama 100319475328460012568 100319475328460012568 No Department of Neurosurgery, School of Medicine, Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran. Mohammadali Yazdanipour 100319475328460012569 100319475328460012569 No Neuroscience Research Center, Trauma Institute, Guilan University of Medical Sciences, Rasht, Iran. Mahdieh Torkashvand 100319475328460012570 100319475328460012570 No Poursina Clinical Research Development Unit, Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran. Ali Ashraf ashraf_adr@yahoo.com 100319475328460012565 100319475328460012565 No Poursina Clinical Research Development Unit, Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran.