Effective circulating volume
The effective circulating volume is the volume of arterial blood effectively perfusing tissue. ECV is a dynamic quantity and not a measurable, distinct compartment. This concept is useful for discussion of cardiovascular and renal physiology.
Though ECV normally varies with extracellular fluid, they become uncoupled in diseases, such as congestive heart failure or hepatic cirrhosis. In such cases, decreased ECV may lead to volume depletion responses and edema.
Decreased ECV can stimulate renin secretion or stimulate a sympathetic nervous system response or prostaglandin release.
