Incidence of and Risk Factors for Prolonged Intensive Care Unit Stay After Open Heart Surgery Among Elderly Patients

Abstract

Objective: Open heart surgery (OHS) is frequently performed on elderly patients. We aimed to investigate the risk factors associated with prolonged intensive care unit (ICU) stay in elderly patients undergoing open heart surgery.

Materials and methods: Medical records of all patients ≥ 75 years who underwent OHS (coronary artery bypass grafting (CABG) and/or heart valve surgery) between June 1, 2013, and December 31, 2020, were retrospectively analyzed. Those staying in the ICU longer than five days were determined as prolonged ICU stay. Patients were divided into two groups, according to ICU stay <5 days and ≥5 days.

Results: Out of the 198 patients included in the study, 130 (65.7%) were male. Seventy patients (35.4%) had prolonged ICU stay. The mean age was higher in patients within the prolonged ICU stay group when compared to the other group (79.9±3.5 years vs.78.1±2.7 years, p<0.001). The patients who used statins and angiotensin-converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARBs) in the preoperative period had a shorter ICU stay compared to those who did not (45% vs 31.4%, p=0.04; 57% vs 42.9%, p=0.03). The history of previous thoracic surgery (2.3% vs 10% p=0.03), emergency surgery (12.5% vs 24.5% p=0.04), and preoperative pacemaker usage (0.8% vs 7%, 1 p=0.01) were higher in the group of patients with prolonged ICU stay compared to the other group. Preoperative ejection fraction (EF)% (47.7±11.3 vs 51.1±8.8, p<0.001) and hemoglobin level (11.8±1.9 mg/dL vs 12.9±1.6, p<0.001) were lower in the group with prolonged ICU stay compared to the other group. Incidence of cardiac arrest (3.9% vs 15.7% p=0.006), presence of arrhythmia (16.4% vs 41.6%,p<0.001), frequency of pacemaker and intra-aortic balloon pump (IABP) usage (0 vs 10% p=0.002; 1.6% vs 8.6% p=0.02), and need for renal replacement therapy (3.1% vs 12.9%,p=0.02) were higher in the group with prolonged ICU stay compared to the other group. According to the logistic regression analysis; higher age (OR: 1.225, 95%CI 1.104-1.360, p<0.001), preoperative pacemaker usage (OR: 0.100, 95%CI 0.01-0.969, p<0.04), preoperative statin non-use (OR: 2.056, 95%CI 1.040-4.066, p<0.03) and preoperative low EF (OR: 0.947, 95%CI 0.915-0.981, p=0.002) were determined as independent risk factors for prolonged ICU stay.

Conclusion: The incidence of prolonged ICU stay after OHS among patients ≥75 years was 35.4% in our cohort. Higher age, preoperative pacemaker usage, preoperative statin non-use, and low preoperative EF were associated with prolonged ICU stay.

Keywords: cardiovascular disease; elderly patient; intensive care unit; open heart surgery; postoperative complications; postoperative mechanical ventilation; prolonged intensive care stay; prolonged stay.