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Discussion Starter · #1 ·
Orthostasis is defined as a rise in pulse rate of more than 10 beats per minute or a decline in systolic blood pressure of more than 20 mmHg when the patient changes position from supine to sitting or standing position.

If orthostasis is positive it means there's 20% blood volume loss.

Blood volume loss larger than this will be demonstrated by the usual tachycardia and hypotension at all position and with no need to demonstrate orthostasis.
 

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i dont think so orthostasis is the normal physiological condition but i think you mean orthostatic changes which is pathological condition indicating significant hemodynamic instability which = at least 20% loss in total blood volume -- > mandates immediate IV volume expansion and prepartion for blood transfusion
 

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I did not ..

i dont think so orthostasis is the normal physiological condition but i think you mean orthostatic changes which is pathological condition indicating significant hemodynamic instability which = at least 20% loss in total blood volume -- > mandates immediate IV volume expansion and prepartion for blood transfusion
I did not say it's a normal physiologic phenomenon!
 
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