pediatrics
Respiratory Distress Syndrome in Neonates
Pathophysiology of Respiratory Distress Syndrome in Neonates
Pulmonary surfactant is a mixture of phospholipids and lipoproteins secreted by type II pneumocytes (see Neonatal Pulmonary Function ). It diminishes the surface tension of the water film that lines alveoli, thereby decreasing the tendency of alveoli to collapse and the work required to inflate them. With surfactant deficiency, a greater pressure is needed to open the alveoli. Without adequate airway pressure, the lungs become diffusely atelectatic, triggering inflammation and Pulmonary Edema . Because blood passing through the atelectatic portions of lung is not oxygenated (forming a right-to-left intrapulmonary shunt), the infant becomes hypoxemic. Lung compliance is decreased, thereby increasing the work of breathing. In severe cases, the diaphragm and intercostal muscles fatigue, and CO2 retention and Complications of RDS include Intraventricular hemorrhage and/or intraparenchymal hemorrhage , periventricular white matter injury, 