Hypoxemic respiratory failure in patients with acute heart failure
- Journal
- Internal and emergency medicine (Q1)
- Published
- 7 September 2026
- Study design
- Unclassified
- Evidence level
- Level 5, Expert Opinion (CEBM 5)
- Authors
- Josep Masip, Pere Llorens, Víctor Gil, Pedro Lopez-Ayala, Begoña Espinosa, Judith Gorlicki, et al.
- PMID
- 42704606
- DOI
- 10.1007/s11739-026-04508-6
Why clinicians should know about it
- Picked for Internal Medicine (paper of the day, 10 September 2026): Hypoxemia common in acute heart failure, prognosis linked
Abstract
INTRODUCTION: The incidence of hypoxemia and the indications for oxygen therapy in patients with acute heart failure (AHF) are not well known. METHODS: A large nationwide registry of unselected AHF patients attended in the emergency department (ED) was analysed. Oxygen saturation by pulse-oximetry (SpO2) was measured on ED arrival, and the ratio SpO2/FIO2 was calculated to adjust for the impact of pre-hospital oxygen therapy, stratifying patients into three groups: normal ratio (≥ 452; corresponding approximately to a SpO2>94%, on room air), mild decrease of the ratio (429-451; SpO2~90-94%) and hypoxemia (≤ 428; SpO2~<90%). Unadjusted and adjusted 30-day all-cause mortality was analyzed by category and restricted cubic spline (RCS). RESULTS AND DISCUSSION: Of 18,904 AHF patients, 6949 (36.7%) had normal SpO2/FIO2, 5438 (28.8%) showed mild decrease of the ratio, and 6517 (34.5%) were hypoxemic. Hypoxemia was documented in 40% of hospitalized patients and was observed in all phenotypes, ranging from 18.6% in acute decompensated heart failure, to 100% in acute pulmonary oedema. The severity of most physiological parameters, the level of biomarkers, the rate of comorbidities and the 30-day all-cause mortality risk were inversely related to SpO2/FIO2. Mortality risk progressively increased for SpO2/FIO2<452 but became nearly flat when it was<350 suggesting that the prognosis did not depend only on the severity of respiratory failure. CONCLUSIONS: Impaired oxygenation was observed in nearly two thirds of patients with AHF attended in ED. Hypoxemia occurred in 40% of those hospitalized, affecting all phenotypes and was associated with more severity and worse prognosis. This should be considered when addressing treatment recommendations for these patients.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.