Postoperative cognitive dysfunction: toward the Alzheimer's disease pathomechanism hypothesis.

The aim of this review is to identify an evidence-based perioperative management for patients affected by Alzheimer's disease (AD) that are scheduled to undergo surgery. This will minimize the negative effects of anesthesia and postoperative sedation and correct those perioperative variables possibly responsible for a decline in cognitive status and a worsening of AD. We here gather evidence on the importance of correct preoperative assessment regarding cognitive and functional status and the presence of preoperative delirium. The potential role of anesthesia, surgery, and postoperative analgosedation as risk factors for development of delirium are herein outlined. Finally, pain assessment instruments, as well as principles of management strategies for postoperative delirium in subjects with AD, are suggested.