Hemodynamic Effects of Fentanyl Vs Dexmedetomidine in Spine Surgery

Spinal surgery is frequently associated with perioperative hemodynamic fluctuations and significant postoperative pain. Maintaining stable intraoperative blood pressure and heart rate is essential to minimize surgical bleeding, protect neural structures, and promote optimal recovery. Dexmedetomidine, a highly selective α₂-adrenergic receptor agonist, provides sedation, analgesia, and sympatholytic effects without causing respiratory depression and may contribute to improved cardiovascular stability during anesthesia. Fentanyl, a potent synthetic opioid, is widely utilized as an analgesic adjunct in general anesthesia but may offer less consistent hemodynamic control. This study is a prospective, interventional, randomized, double-blind controlled trial conducted at Adam Malik General Hospital, Medan, Indonesia, following approval from the institutional ethics committee. A total of 50 adult patients scheduled for elective spinal surgery under general anesthesia were enrolled using consecutive sampling and randomly assigned to receive either dexmedetomidine or fentanyl as part of intraoperative management. Eligible participants were aged 17-60 years and classified as American Society of Anesthesiologists (ASA) physical status I-III. Patients with known drug hypersensitivity, significant cardiac or vascular abnormalities, or contraindications to the study drugs were excluded. Hemodynamic parameters, including mean arterial pressure (MAP) and heart rate, were recorded at baseline (T0) and at predetermined intraoperative time points (T1-T12). The primary outcome measure was intraoperative MAP, while secondary outcomes included heart rate and estimated blood loss. Statistical analyses were performed using independent t-tests or Wilcoxon rank-sum tests, with a significance threshold of p \< 0.05.