Intraoperative Ketamine Versus Saline in Depressed Patients Undergoing Anesthesia for Non-cardiac Surgery

This study examined whether a perioperative intravenous ketamine infusion given as part of anaesthesia produces antidepressant effects compared with volume-matched normal saline in patients with Major Depressive Disorder undergoing non-cardiac surgery.

Ketamine was administered as a single 0.5 mg/kg infusion over 40 minutes during surgery; outcomes include depressive symptom change and perioperative morbidity.