Assessment of the Pulmonary Diffusion Capacity in Healthy Infants and Infants With Chronic Lung Disease

We hypothesize that infants who were born prematurely but are clinically without chronic respiratory disease have a lower lung diffusion capacity than healthy infants born at full term, when evaluated at comparable post-conception ages. In addition, prematurely born infants that develop chronic lung disease have an even lower diffusion capacity than healthy premature infants and full term infants. A lower diffusion capacity, when normalized to lung volume, would be consistent with decreased alveolarization and alveolar surface area in the infants born prematurely. We will study the age range of 1 to 24 month as this represents the period of rapid lung growth.