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

Abstract Background: Research on the impact of small-dose esketamine on perioperative neurocognitive disorder and postoperative depressive symptoms in elderly patients is limited. This study aimed to assess whether administering perioperative small-dose esketamine intravenously would reduce the incidence of perioperative neurocognitive disorder and postoperative depressive symptoms in elderly patients with malignant tumors undergoing elective non-cardiac major surgery. Methods: This trial included 209 patients aged 65 to 86 years undergoing tumor resection who received esketamine (Group E) or not (Group C) during and after surgery. Cognitive function was evaluated using neuropsychological tests as well as the telephone interview for cognitive status-modified (TICSm), and symptoms of depression were assessed using the 17-item Hamilton Depression Rating Scale (HAMD-17). Results: There was no significant difference in postoperative delirium incidence between patients who received esketamine during surgery and those who did not at 1-5 days post-operation. Group E had 12.0% incidence (13 out of 108 patients), while Group C had 10.9% (11 out of 101). Group E showed significantly better results than group C regarding less time required for the trail making test (Part B) during neuropsychological testing, lower incidence of depression, and lower Hamilton depression score at 3, 7, and 90 days post-surgery. Conclusions: Small doses of eketamine given perioperatively improved postoperative depression in elderly patients with malignant tumors. Adverse reactions were not significantly increased. It did not significantly affect postoperative delirium and cognitive function, but it facilitated the recovery of social executive abilities. Trial registration: The study was registered on clinicaltrials.gov.cn on 10/3/2023 (NO. ChiCTR2300069249).