fetal circulation

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fetal circulation

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dreamer
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08/27/06 - 04:36 AM

during fetal life, in which of the following structures is the percent hemoglobin/oxygen saturation level of fetal blood the lowest?

a : ductus arterious

B:left ventricle

C:inferior vena cava

D: umbilical vein

E:right atrium

F:descending aorta

i pick F, anyone agrees?if not,why??

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ManuNastai

08/29/06 - 03:31 AM

I'm not sure, for I cannot recall..

I think is A

Normaly you should think is C, and that would be the answer if you would know that it's talking about the cava under the joining with the ombilical vein (which carries the highest O2 saturation); but lacking that info you can eliminate that answer.

I remember this explination is given somewhere in kaplan or goljan.. The blood caried by the inferior vena cava then reaches the right atrium passes through Botallo's orifice (most of it) in the left atrium and from there in the aorta. The blood coming from the superior vena cava passes through the tricuspid valve into the LV and from there in the PA. Because the resistance is high in the pulm. system and because the lungs are not fuctional, the blood through the ductus arteriosus will flow from the PA to the aorta. Thus, the blood carried by the PA (which originates in the superior vena cava) has a lower saturation.

dreamer
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08/31/06 - 10:32 AM

ManuNastai: thanks a lot ....so is the blood in left ventricle mainly from ivc ??

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ManuNastai

09/01/06 - 01:53 AM

yup

aisha2
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09/06/06 - 05:23 PM

ill go with F

Attached Files:
fetal cir.bmp (167 KB, 40 downloads)

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Cedrick
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09/06/06 - 05:26 PM

interesting

vallia
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09/08/06 - 12:41 AM

I go with A

oxigenated blood from umbilical vein----->IVC---->Right atrium---->foramen ovale--->LA, LV---->Ao ---> to head of fetus

deoxigenated blood from SVC--->RA, RV--->Pulm artery--->ductus arteriosus--->Ao (here mixed with O2 blood)---->to lower part of the fetus

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docarchana
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09/08/06 - 09:51 AM

thanx manunastai and vallia. if in the above q, highest percent is asked, then it will be IVC. right???

fox
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09/08/06 - 05:16 PM

docarchanaa as manunaastai mentioned, the part of IVC ABOVE the joining of umbilical vein will have the highest conc.....

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ManuNastai

09/10/06 - 09:54 AM

#10

actually it would be the umbilical vein because that is wht drives the oxigenated blood from the placenta to the fetus

dreamer
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09/19/06 - 08:28 AM

#11

A is right smiling face

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young_doc
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09/21/06 - 05:07 PM

#12

Lowest (Hb% / O2 Saturation) will occur where O2 saturation is highest.

I say D. Umbilical vein. Has the highest O2 saturation.

Just my guess!

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Leopard
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09/21/06 - 07:29 PM

#13

young_doc wrote:
Lowest (Hb% / O2 Saturation) will occur where O2 saturation is highest.

I say D. Umbilical vein. Has the highest O2 saturation.

Just my guess!

Oh dear young doc

This is unique theory which you are putting forward.Would you please explain it?? I could not understand.Please

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Leopard
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09/21/06 - 07:38 PM

#14

People selecting " A" are absolutely right.

Best of luck

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docswapna
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09/21/06 - 07:39 PM

#15

lowest O2 saturation - ductus arteriosus
highest - umbilical vein

young_doc
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09/21/06 - 08:24 PM

#16

hahaha..i think i got confused with the wording of the question...i thought

" % hemoglobin/oxygen saturation "

was referring to a fraction!

My mistake. Sorry guys.

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