Novel Perioperative Risk Factors and Their Contribution to Postoperative Delirium

Postoperative delirium is a frequent complication in the surgical older population that imposes economic and healthcare costs. Developing methods to identify patients at risk can help lessen the burden of this syndrome. In our first research, we investigated whether burst-suppression during cardiopulmonary bypass (CPB) mediates the effects of known delirium risk factors on postoperative delirium. We found that CPB burst-suppression mediated the effects of physical function, lowest CPB temperature, and electroencephalogram alpha power on delirium. Moreover, patients who presented a decreased intraoperative electroencephalogram broadband power possessed a pre-existing susceptibility to delirium. In our second study, we investigated if preoperative frailty had an impact on postoperative delirium reflected on 180-day mortality. Also, we investigated whether preoperative frailty explains the association between postoperative delirium and mortality. We found that frailty and postoperative delirium are independent risk factors for 180-day mortality in geriatric patients with traumatic orthopedic fractures. Efforts dedicated to independently mitigate the risks associated with frailty and postoperative delirium are necessary.