An updated meta-analysis of 17 randomized controlled trials involving 1,035 people with major depressive disorder found that adding ketamine alone to electroconvulsive therapy does not improve depressive symptoms compared with other anesthetic agents at any time point. Combining ketamine with other anesthetics showed a short-term advantage in reducing depressive symptoms early in treatment, but this benefit did not persist after the full course of ECT or at the end of the study. Most subgroup analyses confirmed the lack of significant effect. Ketamine alone increased blood pressure more than other anesthetics. Results for neurocognitive function were mixed.
In a double-blind randomized trial, 82 frail elderly patients undergoing thoracoscopic radical resection of lung cancer received either intravenous esketamine or a placebo (normal saline) during surgery. Those given esketamine had significantly lower depression scores (HAMD-17) at 7 and 30 days after surgery, indicating less postoperative depression. They also reported better sleep quality in the first week and showed higher scores on a cognitive function test (MMSE) in the first month. Esketamine was associated with higher levels of serum BDNF and 5-HT, lower levels of S100β and NSE, reduced use of anesthetic drugs, fewer side effects like nausea and hyperalgesia, and shorter stays in the recovery room and hospital. Esketamine appears to improve postoperative depressive state, sleep, and cognitive function in this vulnerable group.