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  #1  
Old 06-06-2011
INCOGNITO's Avatar
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Question Anion gap question

A 30 year AIDS male pt is admitted in hospital with severe diarrhea. He has protracted diarrhea for past 3 days.
he appears to be breathing rapidly. pulse is thready and fast.
arterial blood sampling is shown below

arterial CO2 = 28 mmHg
arterial pH = 7.32
plasma cl- = 116 mEq/L
plasma HCO3- = 14 mEq/L
plasma Na+ = 140 mEq/L
plasma K+ = 3.4 mEq/l

What is anion gap in this patient..

a) 5
b) 10
c) 15
d) 20
e) 25

I think due to diarrhea there is no anion gap and answer is (B)

but if we calculate according to equation

Na+ = cl- + HCO3-

It turns out to be 13

What u guys think of it?
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Old 06-06-2011
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I think the answer is B) 10

The calculation was

Na - (Cl + HCO3):

140 - 130

= 10

You can add potassium to this, but Fish says not to.
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  #3  
Old 06-07-2011
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Default it,s B

may be you make something wrong
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  #4  
Old 06-07-2011
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The formula is super clear. Just apply numbers and thats all. Normal anion gap from 8 to 12....so patient has normal anion gap.
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  #5  
Old 06-07-2011
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it's better not to make it 13 anyways, because the patient had diarrhea and hyperventilation, non of which is associated with increased anion gap!
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Old 06-07-2011
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Default this is your formula

Hey anion gap is the anionic gap and then the equation is anion gap= Na+ (Cl - CO3) the right choice is 10

Last edited by ari2003; 06-07-2011 at 05:53 PM.
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