Pulmonary alveolar oedema is a particular pattern of pulmonary oedema where most of fluid build up is into the alveolar spaces. The onset of alveolar edema may also be associated with direct pressure-induced damage to the alveolar epithelium. It can sometimes have a central peri-hilar pattern. Alveolar pulmonary oedema often preceded by interstitial pulmonary oedema and usually develops once the pulmonary venous pressure exceeds 30 mmHg 2.
On chest radiographs, there are often bilateral opacities that demonstate extend in a fan shape outward from the hilum in a ‘batwing’ pattern. With worsening alveolar oedema, the lung opacification can become increasingly homogenous. Air bronchograms can be seen with alveolar oedema 2.
- 1. Gluecker T, Capasso P, Schnyder P et-al. Clinical and radiologic features of pulmonary edema. Radiographics. 1999;19 (6): 1507-31. doi:10.1148/radiographics.19.6.g99no211507 - Pubmed citation
- 2. Khan AN, Al-Jahdali H, Al-Ghanem S et-al. Reading chest radiographs in the critically ill (Part II): Radiography of lung pathologies common in the ICU patient. Ann Thorac Med. 2009;4 (3): 149-57. doi:10.4103/1817-1737.53349 - Free text at pubmed - Pubmed citation