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#1




Calculation of Plasma Volume?
The rapid ingestion of 1200 mL of water will cause the plasma volume to increase by how many mL?
A. 720 mL B. 480 mL c. 400 mL D. 100 mL E. 50 mL Please help! 
#2




Ans C ........ 1/3 will remain in plasma , as it appears to be pure water , which is not isotonic and will diffuse intracellularly by 2/3 ...

#3




the answer is actually D I dont know how to derive to it

#4




dont know how to get 100 ml either .......

#5




out of 1200ml 1/3rd will be in extracellular and 2/3rd will move into intracellular
1/3rd extracellular =400ml extracellular is comprised of 1/4th plasma volume and 3/4 interstitial volume so plasma vol=1/4 multiplied by 400 =100ml Thanks for the question 
#6




Quote:
thank u very much!!!! 
#7




Quote:
Sorry to disappoint , but rule is 2/3 and 2/3 ,intracellular and interstitial respectively (source Kaplan physiology chapter 1) exact answer 133 taking rough round off goes to 100. Correct me if I am wrong.
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#8




Quote:
the ans is exactly 100 ......... 
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usmle_taker (02052012) 
#9




Quote:
Doesn't make difference here but another set of values and I am doomed to be wrong . Thx for thumbs up
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