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  #1  
Old 07-03-2011
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Lungs Which of the following can best explain the flow-volume curve?

A 28 y/o medical student generates the flow-volume loops in the diagram below. Curve W is a normal maximum expiratory flow-volume curve generated when the student is healthy.
Which of the following can best explain curve X?


Which of the following can best explain the flow-volume curve?-screen-shot-2011-07-03-9.10.28-pm.png
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A) Asthma attach
B) Aspiration of meat into the trachea
C) Heavy exercise
D) Light exercise
E) Normal breathing at rest
F) Pneumonia
G) Tuberculosis
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  #2  
Old 07-03-2011
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I think its C..HEAVY exercise..
Expiratory flow is the same but lung volume is decreased..i guess its due to increased RR during exercise ,that is leading to decreased lung volume..
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i think its heavy exercise
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Old 07-03-2011
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Idea!

i think it is E
normal breathing
like he is not using his reserved expiratory and respiratory volumes
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Old 07-03-2011
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Default E?

Can't match any with decrease of lung volume, except normal breath. I go with E.
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  #6  
Old 07-03-2011
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Default Ans.

C.Heavy exercise
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hum...i will go for E)
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Here goes, and im not sure. But doesnt it seem from the loop X that he is not ejecting as much air as he was, ie there is some retention of volume, the end expiratory reading is above the end expiratory of w which is the normal forced expiration loop. so im thinking that its either a normal at rest pattern (without the forceful expiration) or its an obstructive pattern. I don't see any obstructive pattern on the list besides asthma perhaps, and it doesnt look bad enough to completely justify an obstructive loop.So I think its NOrmal breathing at rest, asthma would be a little worse off i...
so when do we get the answer bebix?
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Old 07-04-2011
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Default d

Quote:
Originally Posted by bebix View Post
A 28 y/o medical student generates the flow-volume loops in the diagram below. Curve W is a normal maximum expiratory flow-volume curve generated when the student is healthy.
Which of the following can best explain curve X?


Attachment 1694
click image to enlarge

A) Asthma attach
B) Aspiration of meat into the trachea
C) Heavy exercise
D) Light exercise
E) Normal breathing at rest
F) Pneumonia
G) Tuberculosis
it z from kaplan physio q bank, i think answer z E
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Correct Answer Correct answer

The correct answer is C)

Curve X represents heavy exercise with a tidal volume of about 3 liters. Note that the expiratory flow rate has reached a maximum value of nearly 4.5L/sec during the heavy exercise. This occurred because maximum expiratory air flow is required to move the air through the airways with the high ventilatory frequency associated with heavy exercise.

An asthma attack or aspiration of meat would increase the resistance to air flow from the lungs, making it unlikely that the expiratory air flow rate could approach its maximum value at a given lung volume. The tidal volume should not increase greatly with pneumonia or TB, and it should not be possible to achieve a maximum expiratory air flow at a given lung volume with these diseases.

Curve Z = normal breathing at rest
Curve Y = mild exercise.
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  #11  
Old 07-04-2011
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Quote:
Originally Posted by leo lakhani View Post
it z from kaplan physio q bank, i think answer z E
This qs is not from kaplan though (guyton )
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