1. Structural interdependence of alveolar units
Structural interdependence of alveolar units. The pressure difference across the outermost alveoli is transmitted mechanically through the lung via the alveolar septa. The insets show the author’s idea of what might happen in negative-pressure breathing and positive-pressure ventilation. In negative-pressure breathing (Inset A) the mechanical stress would likely be transmitted from the more exterior alveoli (those closest to the chest wall) to more interior alveoli, so the exterior alveoli might be more distended. In positive-pressure ventilation (Inset B) the lungs must push against the diaphragm and rib cage to move them. The outermost alveoli might be more compressed than those located more interiorly.
Source: Chapter 2. Mechanics of Breathing, Pulmonary Physiology, 8e
Citation: Levitzky MG. Pulmonary Physiology, 8e; 2013 Available at: Accessed: November 02, 2017
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