Quick Question On TPR and Venous return

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Proverbs31

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I dont know why this isnt clicking. Can someone explain this to me easily please:

"Vasodilators-Such as Nitric Oxide, etc...Vasodilate= thus decreasing Total Peripheral Resistance= thereby decreasing Diastolic Blood Pressure= and INCREASing Venous Return to the heart.

Vasoconstriction--> increases TPR and thus Increases Diastolic Pressure."

TPR--refers to the arterioles (RR Path Goljan-p 164) so In my mind I see how vasodilation decreases TPR but HOW DOES IT INCREASE venous return?

Sorry....Im sure I sound ignorant for this one, but maybe its just late and I need sleep but this is not clicking...Doesnt make sense to me. I would think it would Decrease venous return and thus decrease preload...
 
But isn't the exception to this venodilators such as nitrates? There's more pooling of blood in the venous side of the circulation (the capacitance vessels) with the arteriolar side not being affected, decreasing venous return.

Overfiend: I think you were thinking the same thing (i.e. venodilators) as me when you wrote this post http://forums.studentdoctor.net/showpost.php?p=6472393&postcount=6. Correct reasoning, but mixed up side of the circulation 🙂.
 
But isn't the exception to this venodilators such as nitrates? There's more pooling of blood in the venous side of the circulation (the capacitance vessels) with the arteriolar side not being affected, decreasing venous return.

Overfiend: I think you were thinking the same thing (i.e. venodilators) as me when you wrote this post http://forums.studentdoctor.net/showpost.php?p=6472393&postcount=6. Correct reasoning, but mixed up side of the circulation 🙂.

I believe you're correct.

I knew I wasn't crazy. Just mixed to two sides huh. Thanks for the clarification!!!🙂
 
I believe you're correct.

I knew I wasn't crazy. Just mixed to two sides huh. Thanks for the clarification!!!🙂

Thats exactly what I keep doing...forgetting what applies to venous vs Arterial and then I get confused...Ugh.....Wish Golijan gave an easy trick for that... 🙂
Thanks Agranulocy...
 
But isn't the exception to this venodilators such as nitrates? There's more pooling of blood in the venous side of the circulation (the capacitance vessels) with the arteriolar side not being affected, decreasing venous return.

Overfiend: I think you were thinking the same thing (i.e. venodilators) as me when you wrote this post http://forums.studentdoctor.net/showpost.php?p=6472393&postcount=6. Correct reasoning, but mixed up side of the circulation 🙂.



You know what....I think in RR he uses Nitric Oxide for the example and that would be incorrect bc as you say venodilaters...allow the blood to pool in the veins and thus decrease return to the heart....Ahahhh
 
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