Use of dexmedetomidine during light versus deep anaesthesia on postoperative delirium among elderly patients undergoing major non-cardiac surgery: protocol for a multicentre randomised factorial trial

Elderly patients are at a high risk of postoperative delirium (POD), leading to increased postoperative morbidity and mortality. The use of dexmedetomidine and depth of anaesthesia may influence POD. This study aims to determine the effects of dexmedetomidine infusion versus normal saline placebo during light versus deep anaesthesia on POD among elderly patients undergoing major non-cardiac surgery.