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  #1  
Old 06-13-2011
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Default Lung Compliance Curves!

The following lung inflation curves represent different functional states..
which of the points(VECTORS) on these curves represents the most compliant operating range?

Lung Compliance Curves!-photo2424.jpg
click image to enlarge

A
B
C
D
E

pardon i dont say vector before delibrately

Last edited by INCOGNITO; 06-13-2011 at 05:46 PM.
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  #2  
Old 06-13-2011
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I think its A :sorry:

Last edited by Matt78; 06-13-2011 at 05:17 PM.
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Old 06-13-2011
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Since C = V/P

I think is A
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just pray buddy...
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Old 06-13-2011
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OMG bebix u too?
plz read question stem..
i made same mistake..
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Quote:
Originally Posted by IKR123 View Post
OMG bebix u too?
plz read question stem..
i made same mistake..
but the X axis is pressure and the Y is volume...is that right?
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sorry with my handwriting ..ya bout axis u are correct..
but what about answer?
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Quote:
Originally Posted by IKR123 View Post
sorry with ma handwriting ..ya bout axis u are correct..
but what bout ans?
So, if C = change in volume for a given change in pressure...this is the slope?
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actually answer is B
most compliant VECTOR not curve is POINT B on 2nd curve...
conrad explained it that way
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Quote:
Originally Posted by IKR123 View Post
actually answer is B
most compliant VECTOR not curve is POINT B on 2nd curve...
conrad explained it that way
Actually, delta V y greater than delta P in point A
Point B, delta V is less than delta P, so, for the same pressure, the volumen is less...

this in not TRUE!!!!....see post #12

Last edited by bebix; 06-13-2011 at 05:39 PM. Reason: fail!!!
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Old 06-13-2011
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Quote:
Originally Posted by IKR123 View Post
actually answer is B
most compliant VECTOR not curve is POINT B on 2nd curve...
conrad explained it that way
Dude ... you misunderstood Conrad, go see the lecture again
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  #12  
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Quote:
Originally Posted by IKR123 View Post
actually answer is B
most compliant VECTOR not curve is POINT B on 2nd curve...
conrad explained it that way
You are right (conrad)...answer is BBBBB
we have to use the LINE equation...the slope of the line...SORRY!!!

Lung Compliance Curves!-answer.jpg
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  #13  
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curve A shows most compliant lung
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it was not video lecture.. its was live lecture and BTW
most compliant point (VECTOR) is (B)
if a person is at point b he is able to be more complaint when his intrathoracic pressure will be -ve as compared to point A
because after point A (i mean if person starts with point A ) lung compliance is no more available ....
curve tries to be straighten ..
plz correct me if i am wrong and IT means kaplan whole group discussion with conrad fischer and question-expalnation book is also wrong..
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  #15  
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who knows the right answer? how can I be sure whether its A or B?
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finally...
where is ur thanks push..LOL
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  #17  
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Quote:
Originally Posted by IKR123 View Post
it was not video lecture.. its was live lecture and BTW
most compliant point (VECTOR) is (B)
if a person is at point b he is able to be more complaint when his intrathoracic pressure will be -ve as compared to point A
because after point A (i mean if person starts with point A ) lung compliance is no more available ....
curve tries to be straighten ..
plz correct me if i am wrong and IT means kaplan whole group discussion with conrad fischer and question-expalnation book is also wrong..
it is just the slope....of the line...is B (I did the math in post #12, haha)...
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Quote:
Originally Posted by IKR123 View Post
finally...
where is ur thanks push..LOL
Ok...hahaha
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  #19  
Old 06-14-2011
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Default Its b because i think may b its basal portion of lung

At apex of lung there is already expansion of alveoli at the beginning of inspiration but during inspiration alveoli cant expand more howerver intrapleural pressure becomes more negative but at bas of lung alveoli are collapsed and intapleural pressure increases from -3 to -5 so alveolar expansion occurs and so more compliant is basal alveoli during inspiration ..i think i am correct regarding to this i think this graph corresponds to portion of lung most probably its base of the lung ..
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Smile

Theoretical pressure-volume curves illustrating changing compliance with increasing tidal volume:

Lung Compliance Curves!-nice.jpg
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  #21  
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Quote:
Originally Posted by IKR123 View Post
just pray buddy...
answer.. A.
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Old 06-14-2011
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Quote:
Originally Posted by Chemole View Post
answer.. A.
@Chemole, the answer is B....see above
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Old 06-14-2011
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B most compliant lung
compliance = change in vol/ change in pr
greatest change is at point B acc to the vectors used.
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Old 06-14-2011
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Default lung inflation curves

Quote:
Originally Posted by IKR123 View Post
The following lung inflation curves represent different functional states..
which of the points(VECTORS) on these curves represents the most compliant operating range?

Attachment 1503
click image to enlarge

A
B
C
D
E

pardon i dont say vector before delibrately
A z answer
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  #25  
Old 06-14-2011
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Correct Answer

@leo lakhani...the correct answer is B...please see above.
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