It has been just revealed by new reports the fact that the permeable blood-brain barrier could be causing delirium post-surgery. Check out the latest reports about this below.
Permeable blood-brain barrier effects
A new study has found that patients who experience postoperative delirium have increased openings in the blood-brain barrier. Postoperative delirium is a condition of confusion that occurs within a few days after surgery and affects up to 40% of older patients.
It is associated with longer hospital stays, significant distress, and major complications. The underlying causes of postoperative delirium have been difficult to identify, but previous investigations in mice revealed that it could be due to disruptions of the blood-brain barrier, which is a layer of cells in the brain’s blood vessels that prevents substances from entering the brain.
However, assessing the barrier in large human studies has been challenging due to technical limitations.
A new study, published in Annals of Neurology, has successfully addressed the limitations of previous research and provides insights into postoperative delirium.
The study found that patients who had lower cognitive performance before surgery were more likely to experience postoperative delirium.
These findings are significant as they offer a roadmap to tackle a problem that affects millions of older adults in the U.S. every year. Michael Devinney, the corresponding author of the study and an assistant professor in the Department of Anesthesiology at Duke University School of Medicine, suggests that finding a way to prevent the opening of the blood-brain barrier after surgery or identifying the substances that are passing through this barrier and reaching the brain could lead to the development of a therapy to prevent postoperative delirium.
Scientists conducted a study on more than 200 patients aged 60 and above, who underwent non-cardiac and non-neurological surgeries. The study aimed to determine changes in the blood-brain barrier’s permeability by collecting spinal fluid and blood samples before and 24 hours after surgery.
The ratio of albumin protein in these samples was measured as an indicator of the barrier’s fluidity. Cognitive evaluations were conducted before and after surgery to control for cognitive ability as a risk factor for delirium.
The recent study has found that there is a link between increased blood-brain barrier permeability and higher rates of delirium, as well as longer hospital stays for all patients.
This suggests that the increase in permeability is a response to surgery. The study also revealed that people with lower cognitive abilities are more likely to experience delirium.
However, the lower performance on cognitive testing does not necessarily mean that the patient will also experience postoperative blood-brain barrier opening, which is another factor that may increase the risk of delirium.
The study suggests that postoperative delirium may be caused by a two-hit model, involving impaired preoperative cognition as a predisposing factor, and postoperative blood-brain barrier dysfunction as a precipitating factor.