Neurobehavioral outcomes of cardiac surgery

Since the inception of cardiac surgery, postoperative neurobehavioral complaints have prompted intensive studies of neurologic and cognitive outcomes. There is now a wealth of information on the incidence of stroke, delirium, depression, and cognitive outcomes after cardiac procedures. Stroke risk models have been developed to identify patients at high risk. Delirium, although much less objectively studied, still occurs frequently in the immediate postoperative period, but its relationship to long-term cognitive outcome has not been resolved. Postoperative depression may not be as common as was previously thought, and may be related to mood status before surgery. Cognitive decline may be short-term for some aspects of brain function, but more prolonged or delayed in others. Despite these extensive studies, it is not clear whether some of these outcomes are related to the surgical procedure itself, rather than the use of general anesthesia in an older population of patients with extensive atherosclerotic disease. Inclusion of appropriate control groups, longer term follow-up, and larger sample sizes in future prospective studies will improve the design of intervention studies in this patient population.