Effects of ketamine on postoperative cognition: a scoping review.
British journal of anaesthesia July 7, 2025 Connor T A Brenna, Xuan W He, Daheng Liu et al. 8 citations
Postoperative delirium and other cognitive problems are common in older surgical patients. Ketamine, given before or during anesthesia, might protect cognition by reducing inflammation or allowing lower doses of other drugs, but its effectiveness is debated. This review of 58 studies involving 6830 patients found that ketamine provided no cognitive benefit in 60% of studies, while 40% reported reduced incidence or duration of cognitive disorders. No clear patterns emerged for dose, formulation, or timing. Studies assessing cognition only early after surgery were more likely to show no benefit. Most trials were too small and methods too varied for meta-analysis. The inconsistent results support the need for larger, well-designed trials to identify which patient subgroups might benefit.