Emphysema/Lungs related Question

[Futbol99]

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Q: In emphysema, lung elasticity is greatly reduced. Each of the following occurs EXCEPT:

A. Residual Volume increases.
B. Total lung capacity increases.
C. Resting expiration becomes active instead of passive
D. Pleural pressure becomes more negative.

Answer: D

- My problem is I agreed with all the following statements. I'm having trouble understanding the pleural pressure negativity. The way I think about it, which needs to be corrected is: since the lung reduced its elasticity, it would lose its ability to recoil when stretched, so there is less force drawing them inward, therefore the volume is increased, and thus pressure is decreased in the lungs more than normal, and therefore the relativity between lung and atmosphere would mean the pleural pressure is MORE negative (more reduced)...
Why is this wrong? How can I correct my reasoning?

Thanks!

 

[Futbol99]

Or are we looking at it like from the point after inhalation that its stretched out by gas therefore there is more pressure in the inside therefore becomes less negative?

 

[LabratABQ]

Or are we looking at it like from the point after inhalation that its stretched out by gas therefore there is more pressure in the inside therefore becomes less negative?

Inside the intrapleural space or inside the lungs? Those are two very different things... they dont connect, when the intrapleural space and the space inside the lungs are connected, air enters the intrapleural space, which increases the pressure inside the intrapleural space which leads to collapsing of the lungs = pneumothorax.

I think because in emphysema, the walls of the alveolar are destroyed, and results in reduced elastic recoil of the lungs, therefore the process of exhalation is extremely difficult. Thus the person has to force the air out by using the internal intercostal muscles (as oppose to the just relaxing the diaphragm and external costal muscles in healthy individuals for exhalation) to pull the rib cage down and actively decreasing the volume (size) of the thoracic cavity, which then decreases the volume (size) of the intrapleural space = increase in its pressure.

In a way, the lungs cant recoil = cant push air out by itself , but then the muscles come in and save the day .

 

[Futbol99]

Inside the intrapleural space or inside the lungs? Those are two very different things... they dont connect, when the intrapleural space and the space inside the lungs are connected, air enters the intrapleural space, which increases the pressure inside the intrapleural space which leads to collapsing of the lungs = pneumothorax.

I think because in emphysema, the walls of the alveolar are destroyed, and results in reduced elastic recoil of the lungs, therefore the process of exhalation is extremely difficult. Thus the person has to force the air out by using the internal intercostal muscles (as oppose to the just relaxing the diaphragm and external costal muscles in healthy individuals for exhalation) to pull the rib cage down and actively decreasing the volume (size) of the thoracic cavity, which then decreases the volume (size) of the intrapleural space = increase in its pressure.

In a way, the lungs cant recoil = cant push air out by itself , but then the muscles come in and save the day .

Wow, alright, thats perfect!
That makes a lot more sense now! Seems like I was missing the inrapleural space concept.
Thank you!

 

[LabratABQ]

Wow, alright, thats perfect!
That makes a lot more sense now! Seems like I was missing the inrapleural space concept.
Thank you!

The pleasure is all mine! I think it's right, for Pete's sake someone could come along and tell me youre wrong lol

 

[HopefulMDclass2020]

Bump. I understand why D is correct. But I am having a problem seeing why TLC would increase. I would assume it wouldn't change. I get that the RV will increase, but won't our VC decrease by the exact same number, resulting in no net change?

The only logical solution I can think of is, since elasticity is reduced (the force resisting inhalation), we can inhale more air.

Thoughts?

Thanks!

 

[bee17]

The reduction of elastic recoil in the lungs makes it more difficult to get enough air out of the lungs during exhalation. This can lead to hyperinflation of the lungs, which would increase TLC.