Lung surfactant: The indispensable component of respiratory mechanics

Lung surfactant, a lipo-protein complex, is a highly surface-active material found in the fluid lining the air-liquid interface of the alveolar surface. Surfactant plays a dual function of preventing alveolar collapse during breathing cycle and protection of the lungs from injuries and infections caused by foreign bodies and pathogens. Varying degrees of structure-function abnormalities of surfactant have been associated with obstructive lung diseases, respiratory infections, respiratory distress syndromes, interstitial lung diseases, pulmonary alveolar proteinosis, cardiopulmonary bypass surgery and smoking. For some pulmonary conditions, especially respiratory distress syndrome, surfactant therapy is on the horizon.