Effect of small dose esketamine on perioperative neurocognitive disorder and postoperative depressive symptoms in elderly patients undergoing major elective noncardiac surgery for malignant tumors: A randomized clinical trial

Intraoperative low-dose esketamine and postoperative low-dose esketamine combined with sufentanil for patient-controlled intravenous analgesia has been shown to improve postoperative analgesia, alleviate postoperative depressive symptoms, and aid in the recovery of social executive ability. However, this approach did not reduce the incidence of postoperative delirium or postoperative cognitive dysfunction.