Delirium in cardiac surgery: epidemiology, pathogenesis and prevention highlights (Review)

Symptomatic delirium of the early postoperative period is a qualitative disorder (clouding) of consciousness that is deferred, occurs under mainly vascular, inflammatory and metabolic alterations, manifests by variant behavioral disorders. Three clinical studies were conducted to assess the state of the brain after the most frequent elective cardiac surgery — coronary bypass surgery, open-heart valve surgery, open-heart and endovascular aortic valve surgery. 306 patients were included in the listed studies, the controls included the results of the examination of 120 patients who underwent elective eversion carotid endarterectomy and 15 patients who underwent elective abdominal aortic prosthetics. Thus, 441 patients underwent perioperative neurological examination according to a single algorithm. According to the results of the conducted studies, the frequency of symptomatic delirium of the early postoperative period during elective cardiac surgery is 12–14%. Symptomatic delirium of the early postoperative period commonly develops 1–3 days after surgery, the average duration is from 1 to 3 days. Symptomatic delirium of the early postoperative period also increases the likelihood of subsequent development of other clinical types of postoperative cerebral dysfunction – perioperative stroke and deferred cognitive impairment. Most of the symptomatic delirium of the early postoperative period risk factors are preoperative and have vascular origin. Combined use of CAM-ICU and RASS scales is recommended for screening diagnostics of symptomatic delirium of the early postoperative period. The increase of the number of cardiac surgeries demonstrates the necessity of the further improvement of perioperative cerebroprotection, the main directions are promptly diagnosis and correction of risk factors, as well as the use of non-pharmacological and pharmacological methods of brain protection, including the original four-component (inosine, nicotinamide, riboflavin, succinic acid) neuroprotector with cytoprotective and antihypoxic effects, as well as meglumine sodium succinate with antihypoxic and anti-inflammatory effects.