Evaluation of postoperative delirium in cardiac surgery patients with the SDACS screening tool: a multicenter-multiphase study.

Objective: Postoperative delirium is a prevalent complication in cardiac surgery patients, highlighting the importance of early risk factor identification for optimal management. This study aimed to pinpoint risk factors and devise a novel screening tool, the Screening Tool for Delirium After Cardiac Surgery (SDACS), to predict postoperative delirium in cardiac surgery patients after the first day.

Materials and methods: This study employed a multiphase design consisting of three phases. In the first phase, through a scoping review of 38 finally selected published papers, 136 potential risk factors for identifying delirium after cardiac surgery were identified. These risk factors were then incorporated into three Delphi rounds of expert panels to develop a screening tool for postoperative delirium. Finally, 76 potential risk factors were examined on 920 cardiac surgery patients at three academic institutions between 2020 and 2023 (third phase of the study). All predictors were included into a screening instrument (SDACS), and the regression coefficient of each predictor was transformed into a risk score.

Results: Delirium was diagnosed in 53% (n = 488) of 920 patients. Four independent predictors of delirium were identified: chronic opioid use (OR: 4.605, 95% CI: 2.163-9.804), hearing impairment (OR: 6.926, 95% CI: 3.630-12.215), benzodiazepine history (OR: 8.506, 95% CI: 5.651-11.805), and poor sleep quality on the first night after cardiac surgery (OR: 9.081, 95% CI: 6.225-12.248). The cross-validated area under receiver operating characteristics curve (AUC) for the screening instrument was 0.897 (95% CI: 0.876-0.916; P < 0.001).

Conclusion: Chronic opioid use, hearing impairment, benzodiazepine history, and poor sleep quality post-surgery are linked to postoperative delirium in cardiac surgery patients. The SDACS screening tool effectively forecasts this syndrome early, offering bedside nurses a valuable tool for prompt intervention and improved patient outcomes. The SDACS screening tool aids in early delirium risk assessment, enabling timely interventions and better patient outcomes. By predicting postoperative delirium accurately, nurses can address risk factors proactively, potentially reducing its incidence and severity, leading to improved postoperative outcomes for patients.