Effect of Low-dose Esketamine on Postoperative Depression in Patients With Breast Cancer

This parallel, double-blind randomised trial evaluates whether a single intravenous low dose of esketamine (0.25 mg/kg) given after anaesthesia induction reduces postoperative depressive symptoms and pain in women undergoing modified radical mastectomy.

Outcomes include Hamilton Depression Scale at baseline, day 2, day 5, day 30 and day 90; serum leptin at baseline, day 2 and day 5; acute and longer-term pain scores (VAS at multiple timepoints) and analgesic consumption; safety via vital signs, recovery duration and adverse events.