Perioperative Risk Factors for Intensive Care Unit Readmissions and Mortality After Cardiac Surgery

Abstract

Objective: The aim of this study was to identify perioperative risk factors associated with intensive care unit readmission and in-hospital death after cardiac surgery.

Design: Retrospective analysis using a multivariate regression model to identify independent risk factors for intensive care unit [ICU] readmission and in-hospital mortality.

Setting: The study was carried out in a single tertiary-care hospital.

Participants: This was an analysis of 2,789 adult patients.

Interventions: All patients underwent cardiac surgery and were admitted to the intensive care unit perioperatively at the General Hospital Vienna.

Measurements and main results: Among the 2,789 patients included in the analysis, 167 (6%) were readmitted to the intensive care unit during the same hospital stay. Preoperative risk factors associated with ICU readmission included end-stage renal failure (odds ratio [OR] 2.80, 95% CI: 1.126-6.964), arrhythmia (OR 1.59, 95% CI: 1.019-2.480), chronic obstructive pulmonary disease (OR 1.51, 95% CI: 1.018-2.237), age >80 (OR 2.55, 95% CI: 1.189-5.466), and European System for Cardiac Operative Risk Evaluation II >8 (OR 1.40, 95% CI: 1.013-1.940). Readmitted patients were more likely to die than nonreadmitted patients (OR 5.3, 95% CI: 3.284-8.558). In-hospital mortality in readmitted patients was 19.2%, whereas that in the nonreadmitted study population was 5.1%.

Conclusion: Preoperative risk assessment is crucial for identifying cardiac surgery patients at risk of ICU readmission and in-hospital death. The potentially modifiable risk factors pinpointed by this study call for the optimization of care before surgery and after ICU discharge.

Keywords: cardiac surgery; intensive care unit; mortality; readmission.