Incidence and risk factors for delirium after open heart surgery with cardiopulmonary bypass

Abstract

Background & objectives: Postoperative delirium is a prevalent complication, particularly following cardiac surgery, and has detrimental effects on patient outcomes, including increased morbidity and mortality and prolonged stays in the intensive care unit. This study aims to estimate the incidence and identify the risk factors for delirium. Methodology: This prospective observational study was conducted on adult patients undergoing open-heart surgery with cardiopulmonary bypass at the Cardiovascular Surgery Unit at Bachmai Hospital, Vietnam. The Confusion Assessment Method for the ICU (CAM-ICU) was utilized to assess delirium twice daily during the initial four days post-surgery. Perioperative variables were analyzed by univariable and multivariable logistic regression. Results:  Among the 285 patients included in this study, 56 were diagnosed with delirium using the CAM-ICU, representing a prevalence rate of 19.6%. Multivariate regression analysis revealed several independent risk factors for delirium, including advanced age (odd ratio - OR; 95% confidence interval-CI) (1.07; 1.03-1.10), a history of cerebrovascular accident (3.95; 1.31-11.84), prolonged cardiopulmonary bypass duration (1.02; 1.00-1.03), postoperative atrial fibrillation (2.47; 1.15-5.28), and opioid use time (13.65; 5.69-32.75). Conclusion: The incidence of delirium after open heart surgery with cardiopulmonary bypass was 19.6%. Advanced age and a history of cerebrovascular accidents were identified as non-modifiable risk factors for postoperative delirium. Meanwhile, there were three modifiable risk factors, including cardiopulmonary bypass duration, atrial fibrillation, and the time of opioid administration. Abbreviations: CAM-ICU: Confusion Assessment Method for the Intensive Care Unit Key words: Postoperative Delirium; Risk Factors; Incidence; Open-Heart Surgery; Cardiac Surgery Citation: Nguyen TT, Ta DD, Ho HS, Duong HD. Incidence and risk factors for delirium after open heart surgery with cardiopulmonary bypass. Anaesth. pain intensive care 2023;27(6):639−645; DOI: 10.35975/apic.v27i6.2354 Received: Oct 04, 2023; Revised: Oct 28, 2023; Accepted: Oct 31, 2023