Factors affecting duration of stay in the intensive care unit after coronary artery bypass surgery and its impact on in-hospital mortality: a retrospective study

Abstract

BackgroundDifferent risk factors affect the intensive care unit (ICU) stay after cardiac surgery. This study aimed to evaluate these risk factors.Patients and methodsA retrospective analysis was conducted on clinical, operative, and outcome data from 1070 patients (mean age: 59 ± 9.8 years) who underwent isolated coronary bypass grafting CABG surgery with cardiopulmonary bypass. The outcome variable was prolonged length of stay LOS in the CICU stay (> 3 nights after CABG).ResultsUnivariate predictors of prolonged ICU stays included a left atrial diameter of > 4 cm (P < 0.001),chronic obstructive airway disease COPD (P = 0.005), hypertension (P = 0.006), diabetes mellitus (P = 0.009), having coronary stents (P = 0.006), B-blockers use before surgery (either because the surgery was done on urgent or emergency basis or the patients have contraindication to B-blockers use) (P = 0.005), receiving blood transfusion during surgery (P = 0.001), post-operative acute kidney injury (AKI) (P < 0.001), prolonged inotropic support of > 12 h (P < 0.001), and ventilation support of > 12 h (P < 0.001), post-operative sepsis or pneumonia (P < 0.001), post-operative stroke/TIA (P = 0.001), sternal wound infection (P = 0.002), and postoperative atrial fibrillation POAF (P < 0.001).Multivariate regression revealed that patients with anleft atrial LA diameter of > 4 cm (AOR 2.531, P = 0.003), patients who did not take B-blockers before surgery (AOR 1.1 P = 0.011), patients on ventilation support > 12 h (AOR 3.931, P = < 0.001), patients who developed pneumonia (AOR 20.363, P = < 0.001), and patients who developed post-operative atrial fibrillation (AOR 30.683, P = < 0.001) were more likely to stay in the ICU for > 3 nights after CABG.ConclusionOur results showed that LA diameter > 4 cm, patients who did not take beta-blockers before surgery, on ventilation support > 12 h, developed pneumonia post-operatively, and developed POAF were more likely to have stays lasting > 3 nights. Efforts should be directed toward reducing these postoperative complications to shorten the duration of CICU stay, thereby reducing costs and improving bed availability.