Blood volume

Blood volume is the volume of blood (both red blood cells and plasma) in a person's circulatory system. A typical adult male human has a blood volume of some five litres. Blood volume is regulated by the kidneys.

Blood volume (BV) can be calculated given the hematocrit (HC; the fraction of blood that is red blood cells) and plasma volume (PV):


 * $$BV = \frac{PV}{1-HC}$$