Diffuse pulmonary opacification in infants undergoing extracorporeal membrane oxygenation: clinical and pathologic correlation.

Diffuse pulmonary opacification is commonly seen on chest radiographs from infants with severe respiratory failure treated with extracorporeal membrane oxygenation (ECMO). The chest radiographs and clinical records of 18 such infants were reviewed to determine the correlation among degree of abnormality on chest radiograph (as determined by a radiographic score), clinical severity of disease (as measured by ECMO requirements [ECMO flow rate]), and dynamic lung compliance determinations. Increasing lung compliance and decreasing ECMO flow rates correlated well with decreasing (improving) radiographic score. Pathologic changes were mainly those associated with intensive respiratory support and the underlying pulmonary condition. One patient had diffuse pulmonary hemorrhage. Other than bleeding, no distinctive pathologic features could be attributed to therapy with ECMO. We conclude that the degree of pulmonary opacification seen in infants undergoing ECMO therapy is an accurate reflection of markedly decreased lung compliance and lung volumes caused by hyaline membrane formation, pulmonary edema, and atelectasis associated with the various causes of severe respiratory failure.