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  #1  
Old 12-21-2012
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Heart Oxygen Content in PDA

What do you think would happen to the Oxygen content in a patient with PDA?
a. Increase
B. decrease
C. Remain the same
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  #2  
Old 12-22-2012
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oxygen saturation is normal but PO2 decreases. So, I guess Oxygen content would decrease...?
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Old 12-26-2012
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i think as pda is left to right shunt so hoping for oxygen content to increase...........plz tell me also wat is rite ans?
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Old 12-26-2012
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Default A? Not sure

a. Increase

I think it also depends whether the Eisenmonger syndrome has already begun or not
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Old 12-26-2012
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Default ?? remains the same

oxygen content mainly depends on the hb concentration in the RBCs as oxygen content is the total amt of oxygen carried in the blood.

other factors are Sao2 and Pao2 tat determines the O2 content.

Sao2 is increased in the pulmonary artery in PDA
so will this increase the O2 content ??

or will remain the same??
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Old 12-26-2012
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probably increase think so.................not sure......
As there occurs left to right shunt.......
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Old 01-16-2013
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Default remain same

the O2 content in pda remain the same
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Old 01-17-2013
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The answer is increase.
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Old 01-17-2013
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Sarahm
would you pleas explain why it increases.
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Old 01-17-2013
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Quote:
Originally Posted by sami trailer View Post
Sarahm
would you pleas explain why it increases.
Sure. A patient with PDA has a L-R shunt, which means that some of their oxygenated blood in the aorta goes back to the pulmonary arteries. This is because blood flows from high concentration (aorta) to low concentration (pulmonary vessels). As the blood passes to the lung from the pulmonary artery, it gets re-oxygenated, which increases the oxygen saturation. Oxygen content in the blood depends on two factors, PaO2, Hb concentration and Hb saturation. In this case, saturation goes up. As a result, O2 content increases as well.

If this changes into a R-L shunt, the opposite would happen (Saturation decreases).
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Old 01-18-2013
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Thank you
suppose there is 100 ml of unsaturated blood in the pulmonary artery and it needs 20 ml of oxygen to be fully saturated, if 50 ml of arterial aortic blood ( which is already saturated) added to this 100 ml I think we still need the same amount of oxygen to saturate the pulmonary 100 ml blood, in this way no extra oxygen added!!!
confused
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Old 01-18-2013
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Quote:
Originally Posted by sami trailer View Post
Thank you
suppose there is 100 ml of unsaturated blood in the pulmonary artery and it needs 20 ml of oxygen to be fully saturated, if 50 ml of arterial aortic blood ( which is already saturated) added to this 100 ml I think we still need the same amount of oxygen to saturate the pulmonary 100 ml blood, in this way no extra oxygen added!!!
confused
Yes but the saturation happens when both pulmonary and aortic blood go to the lungs where more oxygen is added to blood, it doesn't just simply happen because you're mixing aortic and pulmonary blood together
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