Pathophysiology Etiologies
Airway obstruction (↑ resistance to airflow) Asthma, COPD, bronchiectasis, cystic fibrosis, tumor, foreign body, vocal cord dysfunction, anaphylaxis
Alveolar / Parenchymal disease Pulmonary edema: cardiogenic or noncardiogenic
ILD; pneumonia; atelectasis
(V/Q mismatch)
Large vessel: PE, tumor emboli
Small vessel: PHT, vasculitis, ILD, emphysema, PNA
Chest wall
(↑ resistance to expansion; weakness of respir. muscles)
Pleural disease: large effusion, fibrosis, pneumothorax
Chest wall/diaphragm: kyphoscoliosis, ↑ abd girth
Neuromuscular disorders (ALS, GBS, MG)
Hyperinflation (COPD, asthma)
Stimulation of receptors Chemoreceptors: hypoxemia, metabolic acidosis
Mechanoreceptors: ILD