What effect does increased lung compliance in emphysema have on the tendency of the lungs to collapse?

In emphysema, the lung tissue loses its elasticity and the alveolar walls become damaged, leading to increased lung compliance. Increased lung compliance means that the lungs can expand more easily during inhalation, but this also indicates a reduced ability to recoil during exhalation.

The change in compliance affects the tendency of the lungs to collapse because, with increased compliance, the pressure required to keep the lungs inflated is less than it would be in a healthy state. In healthy lungs, there is a balance between the elastic recoil of lung tissue and the surface tension present in the alveoli. However, in emphysema, the destroyed elastic fibers reduce the lung's ability to return to its resting state after expansion, thereby decreasing the tendency to collapse.

Overall, while the lungs can expand easily due to increased compliance, the loss of elastic recoil leads to a decreased tendency for them to collapse, as there is less elastic force working against lung expansion and more pressure keeping the airways open even if the structural support has diminished.