The incidence of postoperative delirium in clinical trials varies from 4-66%.([FOOTNOTE=Eide LS, Ranhoff AH, Fridlund B, et al. Comparison of frequency, risk factors, and time course of postoperative delirium in octogenarians after transcatheter aortic valve implantation versus surgical aortic valve replacement. Am J Cardiol. 2015;115(6):802-809.],[ANCHOR=],[LINK=]),([FOOTNOTE=Krzych LJ, Wybraniec MT, Krupka-Matuszczyk I, et al. Detailed insight into the impact of postoperative neuropsychiatric complications on mortality in a cohort of cardiac surgery subjects: a 23,000-patient-year analysis. J Cardiothorac Vasc Anesth. 2014;28(3):448-457.],[ANCHOR=],[LINK=]) Patient-specific and iatrogenic factors may place patients at greater risk.([FOOTNOTE=Yang Y, Zhao X, Dong T, Yang Z, Zhang Q, Zhang Y. Risk factors for postoperative delirium following hip fracture repair in elderly patients: a systematic review and meta-analysis. Aging Clin Exp Res. 2017;29(2):115-126.],[ANCHOR=],[LINK=])