Comparison of initial oxygen therapy provided through high-flow nasal cannula versus noninvasive ventilation in patients with acute heart failure

Background: Oxygen therapy with high-flow nasal cannula (HFNC) is being increasingly used in patients with acute heart failure (AHF), but its impact on short-term outcomes has been poorly reported. This study aims to compare short-term outcomes in patients with AHF and respiratory distress who received initial oxygen therapy with HFNC versus noninvasive ventilation (NIV) in the emergency department (ED). Methods: In this prospective observational study, we included all patients diagnosed with AHF in 35 Spanish EDs during January–February 2022 who received either HFNC or NIV as initial oxygen therapy. Patient allocation to initial HFNC or NIV was left to the discretion of the treating emergency physician. The primary outcome was 30-day all-cause mortality. Secondary outcomes included treatment failure (defined as the need for switch of oxygen therapy techniques or escalation to NIV to mechanical ventilation), intensive care unit admission, endotracheal intubation, in-hospital mortality, a composite endpoint of intubation or 7-day mortality, and prolonged hospitalization (>7 days). Associations were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (CIs), using age, sex, and significant patient- and episode-related characteristics as covariates. Results: Of 4301 patients with AHF, 330 (7.7%) were included (median age: 83 years; 57% women): 71 received HFNC and 259 received NIV. Patient characteristics did not significantly differ between groups. A total of 66 (20.1%) patients died during 30-day follow-up with no significant difference between HFNC (21.4%) and NIV (19.8%) groups (aOR: 1.09; 95% CI: 0.55–2.17). There was a significantly higher rate of treatment failure in the HFNC group (23.9% vs. 2.3%, aOR: 17.9; 95% CI: 5.90–54.2), but no significant differences were found for the other secondary endpoints. Conclusion: In patients with AHF and respiratory distress treated in the ED, there was no significant difference in 30-day all-cause mortality between those receiving HFNC or NIV as initial oxygen therapy.