Oxygen supplementation to patients with acute heart failure: Prevalence and prognostic implications

Introduction AHF is a common cause of admission and is associated with poor outcomes. One-third of patients admitted with the diagnosis are readmitted or dead within one month. In acute heart failure (AHF), supplemental oxygen therapy is recommended as part of initial treatment if peripheral oxygen saturation (SpO 2 ) is below 90%. Objectives Our aim was to assess the prevalence of oxygen supplementation therapy at admission amongst patients with AHF. Furthermore, to assess the association between oxygen supplementation and mortality. Methods We conducted a prospective cohort study at the medical ED at a large university hospital in Denmark over a two-year period. Patient records were screened by trained cardiologists to identify patients admitted with AHF and stratified according to oxygen supplementation at admission. One-year all-cause mortality was assessed using Uni- and Multivariate Cox-regression and illustrated with Kaplan-Meier mortality curves. Results The cohort consisted of 408 patients with AHF, of whom 227 (56%) received oxygen supplementation. Patients who received supplemental oxygen had a significantly higher 1-year all-cause mortality with a hazard ratio (HR) adjusted 1.52 (1.09-2.1, p-value = 0.013). Higher levels of oxygen-supplementation were associated with increased mortality. Conclusion More than half of patients with AHF received oxygen supplementation at admission to the ED. Oxygen supplementation at admission was significantly associated with higher mortality among patients with AHF.