Hyperoxemia in Potentially Critically Ill Elderly Patients Treated in Hospital Wards: A Retrospective Study

Introduction:Hyperoxemia is associated with poor outcomes; however, its incidence and risk factors in elderly patients remain unclear. Materials and Method: This retrospective study aimed to identify the incidence of hyperoxemia in potentially critically ill elderly patients treated in wards at an academic tertiary hospital. Elderly patients managed in wards between April 1, 2024, and January 31, 2025, were included. Patients were categorized into two groups: hyperoxemia (partial pressure of oxygen [PaO2] ≥ 120 mmHg) and normoxemia (60 mmHg ≤ PaO2< 120 mmHg). Statistical analyses were conducted using the Chi-square, Fisher’s exact, and Mann–Whitney U tests. Independent risk factors for hyperoxemia were identified through regression analysis. A two-tailed p-value <0.05 was considered statistically significant. Results:A total of 276 elderly patients were included. The incidence of hyperoxemia was 52.2%. Patients with hyperoxemia required intensive care unit admission more frequently and exhibited higher in-hospital and 28-day mortality rates compared to patients with normoxemia. Lymphocyte count ≤ 0.8 × 103/µL (odds ratio [OR], 2.17; 95% confidence interval [CI], 1.27–3.72; p=0.005), atelectasis (OR, 2.03; 95% CI, 1.13–3.67; p=0.019), fraction of inspired oxygen ≥ 40% (OR, 2.10; 95% CI, 1.11–3.95; p=0.022), and type IV respiratory failure (OR, 2.34; 95% CI, 1.09–5.06; p=0.030) were identified as independent risk factors for hyperoxemia. Conclusions: Elderly patients receiving supplemental oxygen therapy are susceptible to hyperoxemia, even when treated in general wards. Further research is warranted to develop preventive strategies for hyperoxemia in this population.