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#1




Calculate Myocardial Oxygen Consumption!
A 65yearold 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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hiratamkeen (10242011) 
#2




E) ...
At least that's what my calculatings skills and lazyness tell me =))
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#3




Bbbbbbbbbbbbbbb



#4




Can you explain your answer please?

#5




What is the source of this question?

#6




i think the ans is B
because if we use the formula of the ficks principle where flow=O2 consumption/AV 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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drhnis (10252011) 
#7




B  is just calculation

#8




The answer is b

#9




i still dont understand how did u calculate the answer

#10




Quote:
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 
The above post was thanked by:  
docnok (10252011), DocSikorski (10242011), Dr.Lacune (08212012), dr.muhamad (10252011), Learner (10252011) 
Tags 
Cardiovascular, Physiology, Step1Questions 
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