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10 Posts

crista
Forum Guru

Topics: 121
Posts: 408

04/05/04 - 05:26 PM

Which one of the following will decrease in a person with ventilation-perfusion (V/Q) abnormalities?

A. Anion gap
B. Arterial pH
C. Arterial carbon dioxide tension
D. Alveolar-arterial (A-a) gradient for oxygen
E. Alveolar ventilation

asmi
Forum Hero

Topics: 1043
Posts: 4,609

04/05/04 - 05:36 PM

Iam sorry its A :oops:

A-a usually increases and Pao2 decreases(hypoxemia)...may be acidosis

crista
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Topics: 121
Posts: 408

04/05/04 - 05:38 PM

why d?

Idiopathic
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Topics: 19
Posts: 641

04/05/04 - 06:48 PM

The A-a gradient should increase. Shouldnt the answer be B? Less oxygen, is essentially what the question is saying, and that will cause a mild acidosis, at any rate.

Anion gap would potentially increase
Arterial CO2 tension would increase
Alveolar ventilation would increase, to compensate

oddissy4u
Forum Guru

Topics: 107
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04/05/04 - 10:02 PM

if i recall correctly arterial alveolar gradient can remain same as in perfusion limited abnormalities!! :roll:

Idiopathic
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04/05/04 - 10:28 PM

It will certainly not decrease. A-a gradient increases in:

ventilation abnormalities
perfusion abnormalities
diffusion abnormalities
mixed abnormalities

Idiopathic
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Posts: 641

04/05/04 - 10:29 PM

"asmi" wrote:
Iam sorry its A :oops:

A-a usually increases and Pao2 decreases(hypoxemia)...may be acidosis

decreased anion gap? you dont mean that. lactic acidosis would increase the anion gap.

usmleasr
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Topics: 105
Posts: 970

04/06/04 - 05:36 AM

good discussion guys...i think it is arterial ph.that is decreased..what is the ans crista

asmi
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Topics: 1043
Posts: 4,609

04/06/04 - 09:37 AM

"Idiopathic" wrote:

"asmi" wrote:
Iam sorry its A :oops:

A-a usually increases and Pao2 decreases(hypoxemia)...may be acidosis

decreased anion gap? you dont mean that. lactic acidosis would increase the anion gap.

I didn't mean that idiopathic ...

could you explain the answer crista ?

crista
Forum Guru

Topics: 121
Posts: 408

04/06/04 - 11:54 AM

#10

I don;t have the answer and because of that I put it here,hoping to find one...

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