Capillary Hematokrit - What Does It Mean?

The hematocrit of capillary blood bears little relation to the hematocrit of arterial blood. Capillary hematocrits are lower than arterial values, and, most importantly, the capillary hematocrit fluctuates in parallel with tissue metabolic activity and the contractile state of the arterioles. This suggests that the capillary hematocrit could be a controlled variable with a central role in the regulation of tissue oxygenation.