Intraoperative Goal-directed Blood Pressure and Dexmedetomidine on Outcomes

Loading dose dexmedetomidine (0.6 mcg/kg for 10 min) administered before anesthesia induction, followed by a continuous infusion (0.5 mcg/kg/h) until 1 hour before the end of surgery.

Loading dose placebo administered before anesthesia induction, followed by a continuous infusion until 1 hour before the end of surgery.

Blood pressure is maintained within ±10% of baseline with noradrenaline infusion and fluid management.

Blood pressure is maintained according to routine practice, i.e., systolic blood pressure \> 90 mmHg or within ±30% of baseline within intermittent ephedrine or phenylephrine.