Use of nebulized bronchodilators in acute heart failure: impact on outcomes

To investigate which patient- and episode-related factors are associated with apparently unsupported use of bronchodilators in patients diagnosed with acute heart failure (AHF) in the emergency department (ED) and whether their use impacts short-term outcomes.

This is a secondary analysis of the EAHFE Registry that includes unselected AHF patients attended at 47 Spanish emergency departments (EDs) from 2014 to 2022. Patients with previous diagnosis of chronic pneumopathy and those receiving chronic treatment with or being discharged on bronchodilators were excluded. The remaining patients, for whom use of bronchodilators was considered clinically unsupported, were included and divided according to if nebulized bronchodilator therapy was used during ED care. The type of bronchodilator was recorded (beta-agonist, anticholinergic, or both). We investigated the association of bronchodilator use with 41 patient- and episode-related factors. Short-term outcomes consisted of hospitalization, in-hospital all-cause mortality, prolonged hospitalization (> 7 days), and 30-day all-cause mortality and association with bronchodilators use was estimated in adjusted models.

10,514 patients fulfilled inclusion and exclusion criteria and were finally analyzed in this study (median age: 84; IQR: 76-88; female: 61%); of them, 2,206 (21%) received bronchodilators (beta-agonists 3%, anticholinergics 7%, both 11%). Bronchodilator therapy was directly associated with infection as trigger of decompensation (adjusted OR = 3.881, 99%CI = 3.386-4.450), pulse oximetry < 95% (1.557, 1.374-1.784), exertional dyspnea (1.492, 1.098-1.895), functional impairment (1.331, 1.129-1.569), signs of low cardiac output (1.307, 1.091-1.567), and hyponatremia (1.227, 1.023-1.472). Similar results were found in individual bronchodilators analysis. Regarding outcomes observed in the whole cohort, hospitalization occurred in 73.5% (adjusted OR 1.403 for patients treated with bronchodilators, 95%CI = 1.232-1.597), in-hospital death in 7.9% (1.279, 1.044-1.568), prolonged hospitalization in 47.1% (1.015, 0.900-1.146), and 30-day death in 9.9% (adjusted HR 1.215, 1.054-1.401). We found very similar estimates of risks when bronchodilators were considered individually, except for need of hospitalization and use of anticholinergics (1.096, 0.910-1.319).

In AHF patients with no documented need of bronchodilators, ED nebulized therapy is relatively frequent and may be associated with worse short-term outcomes, irrespective of the type of bronchodilator used (beta-agonists, anticholinergics, or both). Based on the nature of the study, whether these negative effects are related to bronchodilators themselves or whether bronchodilator treatment is just a marker of more severely decompensated patients is not definitively responded by this study. We accordingly suggest that emergency physicians should stop prescribing bronchodilators to patients with AHF in the absence of a clear indication for their use.