High altitude pulmonary edema is a subtype of pulmonary edema and is caused by prolonged exposure to an environment with a lower partial oxygen atmospheric pressure.
It occurs most frequently in young males and ~24-48 hours after they have made a rapid ascent to heights greater than 2,500-3,000 meters and have remained in that environment.
Reported clinical manifestations include:
- dyspnea at rest
- cough with frothy pink sputum production
- neurological disturbances associated with concomitant brain edema
The pathogenesis is considered to be from the altered permeability of the alveolar-capillary barrier secondary to intense pulmonary vasoconstriction and high capillary pressure 1,4.
This, in turn, induces endothelial leakage, which results in interstitial and alveolar edema without diffuse alveolar damage.
Chest radiographic features can vary with the degree of hypoxemia.
Central interstitial edema with peribronchial cuffing, ill-defined vessels, and a patchy, frequently asymmetric pattern of airspace consolidation is usually seen. A few Kerley lines may also be visible.
In mild high-altitude pulmonary edema, consolidation may be subtle or absent with little or no involvement of the lung periphery. In severe cases, there may be a tendency to form more confluent changes which can eventually involve the entire lung parenchyma.
- 1. Gluecker T, Capasso P, Schnyder P et-al. Clinical and radiologic features of pulmonary edema. Radiographics. 19 (6): 1507-31. Radiographics (full text) - Pubmed citation
- 2. Bärtsch P. High altitude pulmonary edema. Respiration. 1997;64 (6): 435-43. - Pubmed citation
- 3. Vock P, Brutsche MH, Nanzer A et-al. Variable radiomorphologic data of high altitude pulmonary edema. Features from 60 patients. Chest. 1991;100 (5): 1306-11. doi:10.1378/chest.100.5.1306 - Pubmed citation
- 4. Swenson ER, Maggiorini M, Mongovin S et-al. Pathogenesis of high-altitude pulmonary edema: inflammation is not an etiologic factor. JAMA. 2002;287 (17): 2228-35. JAMA (link) - Pubmed citation