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  #1  
Old 10-22-2011
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Heart Calculate Myocardial Oxygen Consumption!

A 65-year-old man is hospitalized with severe chest pain. Various studies are done, including measurements of coronary blood flow and coronary sinus O2 content.

The values obtained are:
Coronary blood flow 50 mL/min per 100 g of heart
Arterial O2 content 19 mL O2/dL blood
Coronary venous O2 content 2 mL O2/dL blood

What is the myocardial O2 consumption per 100 g of cardiac muscle is (in mL O2/min)

(A) .12
(B) 8.5
(C) 9.5
(D) 200
(E) not calculable from these data
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Old 10-22-2011
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E) ...
At least that's what my calculatings skills and lazyness tell me =))
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Old 10-23-2011
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Bbbbbbbbbbbbbbb
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Old 10-24-2011
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Can you explain your answer please?
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Old 10-24-2011
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What is the source of this question?
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Old 10-24-2011
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i think the ans is B

because if we use the formula of the ficks principle where
flow=O2 consumption/A-V
we have the flow.and we have arterial(A) and venous(v) oxygen concentration so we can calculate the Oxygen(O2) uptake.
Atleast thats what i can think how we need to calculate
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Old 10-24-2011
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B - is just calculation
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Old 10-24-2011
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The answer is b
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Old 10-24-2011
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i still dont understand how did u calculate the answer
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Old 10-24-2011
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Quote:
Originally Posted by docnok View Post
A 65-year-old man is hospitalized with severe chest pain. Various studies are done, including measurements of coronary blood flow and coronary sinus O2 content.

The values obtained are:
Coronary blood flow 50 mL/min per 100 g of heart
Arterial O2 content 19 mL O2/dL blood
Coronary venous O2 content 2 mL O2/dL blood

What is the myocardial O2 consumption per 100 g of cardiac muscle is (in mL O2/min)

(A) .12
(B) 8.5
(C) 9.5
(D) 200
(E) not calculable from these data

The calculation formula is MVO2=(CaO2 -CvO2)XCBF
but first you should convert 19 and 2 per DL to Grams they will be 19/100=0.19 and 2/100=0.02 so then you will calculate easily , as1dl is 100 gram
(0.19 -0.02)x50=8.5
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