Step I emphysema in pathoma

[strawberry10]

In Pathoma, Dr. Sattar says elastic recoil pulls open the walls of the bronchioles in order to keep it open during expiration. He continues to say that in emphysema, you lose elastic recoil because alveoli are destroyed, so bronchioles collapse and causes obstruction. However, I thought the elastic recoil has a natural tendency to collapse toward the airways, not pull out. So, in emphysema, because you don't have elastic recoil, it can't collapse as well and push the air out to expire. Can someone clarify for me? Thanks!

 

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its not that normally the elasticity helps force the airways closed to push the air out, i thonk youre understanding this wrong. basically the alveoli are all connected. pulling and putting tension on each other to keep the airway OPEN during exhalation. Think about letting the air out of a balloon while being allowed to grab the end and pull and hold it open, versus not being allowed to do this. When is more air allowed to escape more efficiently? In emphysema, if many alveoli are destroyed and there isn't tension holding the airway open, as stuff collapses upstream (proximal) during exhalation there is air- trapping in the distal airways. this leads to increased reserve volume (but decreased functional reserve) and hyperinflation of the lungs. does this help at all?