Desarrollo y validación de una escala predictora de riesgo de delirium en cirugía cardiacadeliprecas (delirium prevention cardiac surgery)

Abstract

Introduction Postoperative delirium is a serious complication that increases patient morbidity and mortality and hospital stay and costs, the incidence of which increases in patients undergoing cardiac surgery. The objective of the study therefore is to develop and validate a preoperative model for predicting the risk of delirium for patients undergoing cardiac surgery. Material and methods A multicenter prospective observational study was designed in six critical care units in Spain. 689 consecutive cardiac surgery patients, aged 18 years or older, were registered. The main study variable was the development of postoperative delirium, diagnosed by the Confusion Assessment Method in Intensive Care Units (CAM-ICU), during the stay in the critical care unit after cardiac surgery. Results A preoperative risk prediction model for the development of postoperative delirium was developed with 345 consecutive patients undergoing cardiac surgery and it was validated with another 344 patients. 17.1% (n = 59) and 16.9% (n = 58) of the patients developed delirium, respectively in the development and validation groups of the predictive model. The DELIPRECAS (DELIrium PREvention Cardiac Surgery) model contains four preoperative risk factors: age over 65 years (OR 1.11, 95% CI 1.16-7.89, p = 0.023), score of the Mini-State Exam Mental (MMSE) of 25-26 points (possible deterioration of cognitive function) (OR 2.29, 95% CI 4.49-21.85 p = 0.000) or <25 (deterioration of cognitive function) (OR 1, 65, 95% CI 2.05-13.19, p = 0.001), insomnia requiring medical treatment (OR 1.11, 95% CI 1.44-6.38 p = 0.004) and low physical activity (walking less than 30 minutes a day) (OR 1.01, 95% CI 1.31- 5.77, p = 0.008). The model has an AUROC of 0.825 (95% CI: 0.76 to 0.89). Validation resulted in an AUROC of 0.79 (0.73 to 0.85) while the AUROC of pooled patients (n = 689) was 0.81 (0.76 to 0.85). The pooled data resulted in an overall calibration slope of 0.97 with a -0.24 intercept, indicating good calibration. We stratified the patients into low (0-20%), moderate (> 20-40%), high (> 40-60%) and very high (> 60%) risk groups of developing postoperative delirium, with PVV and NPV for the very high-risk group of 70.97% and 85.56%, respectively. Conclusion The DELIPRECAS model, consisting of four well-defined clinical risk factors, can predict the risk of developing postoperative delirium in the preoperative period in patients undergoing cardiac surgery. An automated version of the risk calculator is available.