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Old 06-01-2012
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Thumbs Up TPR, venous return and CO summary...

This is a summary of what (As far as I understand) happen with CO, TPR, and venous return in different situations... Please, feel free to correct me or comment

  • Increase TPR ---> reduce venous return = decrease CO
  • Increase TPR + venoconstriction ----> increase CO
  • Valsalva ---> increased intrathoracic pressure ---> decreased venous return = decrease CO (No change in TPR)
  • Standing up ---> decrease venous return = decrease CO (No change in TPR)
  • Squatting/hand-griping ---> increased TPR + increased venous return = increase CO (decrease R-L shunt in ToF)
  • Leg rising ---> increased venous return = increase CO (no change in TPR)
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Old 06-01-2012
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Originally Posted by Dr. Mexito View Post
This is a summary of what (As far as I understand) happen with CO, TPR, and venous return in different situations... Please, feel free to correct me or comment


  • Squatting/hand-griping ---> increased TPR + increased venous return = increase CO (decrease R-L shunt in ToF)
I dont think squatting or hand-grip increases venous return. It increases TPR, therefore afterload is increased resulting in less blood being pumped out, the reason why we get increased murmurs of most conditions but decreased murmur sound of HOCM.
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Old 06-01-2012
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I dont think squatting or hand-grip increases venous return. It increases TPR, therefore afterload is increased resulting in less blood being pumped out, the reason why we get increased murmurs of most conditions but decreased murmur sound of HOCM.
Squatting does increases venous return... I was looking for that answer since long time ago... here you can read why

Effect of Squatting on Preload???

Effect of squatting on TOF murmurs?


Is not a long read (like 5 minutes), but for sure can help you to clarify this topic...
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Old 06-01-2012
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Squatting increases venous return. But doesn't hand griping just increase TPR with no effect on venous return, the result being a slight decrease in CO.
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