cardiac output

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cardiac output

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6 Posts

dreamer
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Topics: 52
Posts: 152

09/23/06 - 08:09 AM

a 23 year old woman decides to donate her left kidney to her brother ,who has bilateral renal failure.blood flow was 600ml/min and vascular resistance was 0.16mmhg/ml/min in her kidney before it was removed.

q: will the cardiac output increase or decrease??

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Leopard
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Topics: 30
Posts: 401

09/23/06 - 11:20 AM

Cardiac output should decrease.

Reason goes as follows

Every organ is placed a parallel resister.The rule is

Additiion of parallel resistance decreases TPR
Removal of parlallel resistance increases TPR

It means by removal of kidney from the lady one parallel resister is removed which leads to increase in TPR

Venous return = MAP - RAP/TPR

MAP = mean arterial pressure

RAP = right atrial pressure

So venous return dercreases -----------> decrease in Cardiac output

Another thought most welcome

Best of luck

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young_doc
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Topics: 55
Posts: 732

09/23/06 - 05:49 PM

Yes, CO decreases.

http://advan.physiology.org/cgi/reprint/277/6/S17...

Pay special attention to page 3. Directly answers this questions!

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dreamer
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Topics: 52
Posts: 152

09/24/06 - 03:16 AM

thanks leopard&young_doc.

young_doc , i feel nervous by seeing your number is changing everyday:P just kd.gl with your exam smiling face

you will get 99, god will help you smiling face

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Leopard
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09/24/06 - 03:33 AM

Thanks

Best of luck

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young_doc
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09/24/06 - 07:29 AM

dreamer wrote:
thanks leopard&young_doc.

young_doc , i feel nervous by seeing your number is changing everyday:P just kd.gl with your exam you will get 99, god will help you

haha..

if you're nervous then you can imagine how I feel!!!

Thank you. Goodluck to you too.

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