Melatonin vs Metoprolol or Dexmedetomidine to Improve Surgical Field in FESS

This randomized controlled study at Zagazig University Hospitals will include 112 patients undergoing elective functional endoscopic sinus surgery, allocated into four groups (Melatonin, Metoprolol, Dexmedetomidine, Control). Preoperatively, patients will provide consent, undergo history, clinical and airway assessment, baseline vitals, laboratory tests, and serum cortisol and glucose measurement. Intraoperatively, standard monitoring will be applied, and study drugs administered according to group. Anesthesia will be induced with propofol, fentanyl, and atracurium, and maintained with isoflurane and controlled ventilation. Hemodynamics will be continuously monitored, and surgical field graded using ACS score, with interventions for hypotension, bradycardia, or tachycardia as needed. Postoperatively, emergence agitation, hemodynamics, and drug-related side effects will be recorded, and surgeon satisfaction assessed with a 5-point Likert scale.