1. Dynamic airway compression
Dynamic airway compression. At the end of deep inspiration (A), A positive transmural pressure maintains open airways. In the example of forced expiration, shown in (B), 35 cm H2O is added to both alveolar pressure and intrapleural pressure (Pip = − = +25; Pa = = + 35). Airways are compressed by high intrapleural pressure. The transmural pressure compressing the airways increases with distance from the alveolus because pressure inside the airway decreases from the alveolus to the mouth. Small airways only have radial traction forces to prevent airway collapse.
Source: Pulmonary Physiology, Medical Physiology: The Big Picture
Citation: Kibble JD, Halsey CR. Medical Physiology: The Big Picture; 2015 Available at: Accessed: October 27, 2017
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