There is recent, but limited evidence to suggest that anesthetic depth is associated with poor postoperative cognitive outcomes. Specifically, several studies suggest that deeper level of anesthesia is associated with increased incidence of postoperative delirium and longer-term cognitive decline. In fact, some suggest that older patients undergoing surgery should routinely be monitored with an anesthetic depth monitor to allow the titration of anesthetics or sedation medications to lighter levels to promote better postoperative cognitive outcomes. However, such a practice has never been validated or proven to be feasible or safe. Accordingly, the investigators plan an exploratory study to determine the feasibility and safety of randomizing patients undergoing major surgery to receive deep vs. light anesthetic levels during surgery.
THE EFFECTS OF LIGHT vs DEEP ANESTHESIA ON POSTOPERATIVE COGNITIVE OUTCOMES
In this exploratory grant, the investigators aim to determine whether two different anesthetic depths as measured by an anesthetic depth monitor can be practiced uniformly by a number of anesthesia providers and with safety across a large group of older surgical patients. The investigators will use a randomized control trial design to randomize 232 patients in receiving "light" vs "deep" anesthesia as measured by an anesthetic depth monitor. Postoperative outcomes will include delirium and cognitive measurements.