Postoperative Delirium in Patients on Cardiopulmonary Bypass for Cardiovascular Surgeries: Incidence and Influencing Factors

  Objective  To investigate the incidence and influencing factors of postoperative delirium (POD) and subsyndromal delirium (SSD) in patients connected to cardiopulmonary bypass during cardiovascular surgeries.

  Methods  We collected the general data and the data for the perioperative hematological, physiological, and biochemical indicators and the surgical and therapeutic conditions of patients connected to cardiopulmonary bypass during the course of cardiovascular surgeries conducted at a tertiary-care hospital in Hubei province between May 2022 and September 2022. The outcome indicators, including the incidence of POD and SSD, were assessed with the Nursing Delirium Screening Scale (Nu-DESC). Multinomial logistic regression was performed to analyze the influencing factors of patients with different statuses of POD and SSD.

  Results  Among the 202 patients, the incidence of SSD, SSD progressing to POD, and no POD or SSD (ND) progressing to POD were 13.4%, 6.4%, and 34.2%, respectively. Regression analysis showed that, with ND patients as the controls, the influencing factors for SSD were preoperative blood glucose (odds ratio [OR]=0.38, 95% confidence interval [CI]: 0.19-0.76), intraoperative platelet transfusion (OR=0.37, 95% CI: 0.15-0.92), intraoperative etomidate (OR=0.93, 95% CI: 0.87-0.98), and postoperative total bilirubin level (OR=1.04, 95% CI: 1.01-1.07). For the progression of SSD to POD, the influencing factors were age (OR=1.09, 95% CI: 1.01-1.17), ASA classification of IV and above (OR=10.72, 95% CI: 1.85-62.08), intraoperative dexmedetomidine (OR=1.01, 95% CI: 1.003-1.02), and the duration of mechanical ventilation (OR=1.04, 95% CI: 1.01-1.07). For the progression of ND to POD, the influencing factors were age (OR=1.06, 95% CI: 1.02-1.10), middle or high school education (OR=0.35, 95% CI: 0.15-0.83), and the duration of mechanical ventilation (OR=1.04, 95% CI: 1.01-1.07).

  Conclusion  Age, education, ASA classification, preoperative blood glucose, intraoperative platelet transfusion, intraoperative etomidate, intraoperative dexmedetomidine, postoperative total bilirubin, and the duration of mechanical ventilation are influencing factors for different statuses of POD and SSD among patients connected to cardiopulmonary bypass when they are undergoing cardiovascular surgeries. The influencing factors vary across groups of patients with different statuses of POD and SSD. Therefore, we should accurately assess the risk factors of patients with different statuses of POD and SSD and carry out corresponding interventions, thereby preventing or reducing the occurrence of POD and SSD, and ultimately promoting enhanced recovery after surgery.