Question about Obstructive/Restrictive Lung Disorders

[Ctorch8]

My book explains that COPD mainly affects exhalation due to air trapping and restrictive disorders affect inhalation due to issues with lung compliance.

So I understand how emphysema would trap air due to a loss of elasticity in alveoli. They would not be able to efficiently go back to their normal volume after exhalation essentially leaving air trapped inside them. I'm confused about chronic bronchitis because I don't understand how it wouldn't affect inhalation as well when the bronchioles are inflamed and clogged with mucus?

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[pms_testosterone]

It's because of the positive pressure during exhalation. The pressure acts to compress/pinch the airways. This makes the muscle contraction and thick mucus of chronic bronchitis more of a problem during exhalation than inhalation. (During inhalation, there is negative pressure and the airways expand.)

https://courses.washington.edu/conj/resp/copd.htm

https://www.hindawi.com/journals/pm/2012/542769/ (section 3.1)

Edit: wait why are you studying for USMLE if you're not a med student yet?