Different Doses of Dexmedetomidine on Anesthesia and Analgesia Requirement and Recovery Characteristics during Bispectral Index-Guided Total Intravenous Anesthesia for Endscopic Trans-Sphenoid Resection of Pituitary Adenoma

INTERVENTION: Dexmedetomedine 0.5 microgram Dexmedetomedine 1 microgram Normal saline Placebo control CONDITION: ; Anaesthesia Anaesthesia PRIMARY OUTCOME: Total propofol consumption SECONDARY OUTCOME: Incidence of adverse events Surgical field satisfaction Total amount of fentanyl consumption INCLUSION CRITERIA: ‐ Patients scheduled for elective endoscopic resection of pituitary tumor. ‐ American Society of Anesthesiologists (ASA) physical status: I‐III ‐ Age: 20‐60 years ‐ Gender: either sex. ‐ Patients with Glasgow Coma Scale score (GCS) above 12.