Surfactant spreading on thin liquid layers
Pulmonary surfactant is a vital component of the liquid layer that lines lung airways and alveoli because, by reducing the surface tension at the air-liquid interface, it helps to maintain high lung compliance and to retard the surface-tension-driven instabilities that lead to airway closure. Since the lungs of prematurely born infants may not produce sufficient quantities of natural surfactant, a substitute may be delivered to them, either by inhalation of an aerosol or by direct intratracheal instillation. The delivered surfactant spreads throughout the lung under the action of gravity, surface-tension gradients and surface diffusion.
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