Acute kidney injury and postoperative delirium

Postoperative acute kidney injury (AKI) and postoperative delirium (POD) are two of the most common complications after surgery. It is essential to understand their common mechanisms not only to prevent and predict the occurrence of these complications, but also to guide perioperative management and improve surgical outcomes. This review summarizes the recent literature focused on these postoperative complications and explores the relationship between AKI and POD. Clinical studies suggest that AKI and POD may coexist or occur sequentially during the perioperative period, particularly in susceptible patients undergoing major surgery. Some research findings indicate that the brain and the kidney exhibit bidirectional communication that is affected by systemic inflammation, drug accumulation, uremic toxins, vascular endothelial injury, and fluid volume redistribution during the perioperative period. AKI and POD may share pathophysiological mechanisms involving multiple interacting pathways, leading to impairment of renal and cerebral functions.