As the population ages, more older adults undergo surgery, and doctors face a growing challenge: how to protect memory and thinking after anesthesia. Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are common complications in elderly patients. These conditions can lead to longer hospital stays, higher medical costs, and even long-term cognitive problems. Recently, researchers have been looking at the role of ketamine in geriatric anesthesia and its potential impact on brain health.
What is Ketamine in Geriatric Anesthesia?
Ketamine is an anesthetic that works by blocking NMDA receptors in the brain. Unlike other anesthetics, it usually does not depress breathing and maintains stable blood pressure, making it appealing for elderly patients who may be more fragile. Beyond its anesthetic use, ketamine is also being studied for possible neuroprotective effects—helping shield the brain from stress and inflammation during surgery.
The Potential Benefits
Some studies suggest that low doses of ketamine in geriatric anesthesia—typically between 0.3 and 0.5 mg/kg—may help reduce inflammation in the brain and lower the chances of developing POCD. This protective effect could be especially helpful for patients at risk of memory decline after surgery. By calming the brain’s immune response, ketamine might help preserve cognitive function in certain patient groups.
The Risks and Concerns
Despite these promising findings, ketamine is not without risks. At higher doses, ketamine can cause confusion, hallucinations, or even worsen delirium in older adults. This dose-dependent effect makes it challenging to determine the safest balance between benefits and side effects. Different studies have reported conflicting results, partly because of variations in patient populations, dosing schedules, and methods of measuring cognition.
The Path Forward
Right now, there is no clear agreement on how ketamine should be used in elderly surgical patients. Researchers emphasize the need for larger, multi-center trials to determine safe and effective dosing strategies. They also call for more research on which groups of older patients might benefit the most and whether ketamine should be used alongside other anesthesia methods.
Conclusion
Ketamine in geriatric anesthesia offers both promise and caution. At carefully controlled doses, it may protect against cognitive decline after surgery, but higher doses carry risks of delirium and other psychiatric side effects. Until more research provides clarity, ketamine use in elderly anesthesia should be approached with caution and individualized care.
References
- You S, Li Z. The impact of ketamine on cognitive outcomes in geriatric anesthesia: a comprehensive review. Front Psychiatry. 2025;16:1594730 . doi:10.3389/fpsyt.2025.1594730 https://pubmed.ncbi.nlm.nih.gov/40809865/
- Sun J, Du X, Chen Y. Current progress on postoperative cognitive dysfunction: an update. J Integr Neurosci. 2024;23:224. doi:10.31083/j.jin2312224 https://pubmed.ncbi.nlm.nih.gov/39686047/