Glossary
Haematocrit
Haematocrit is the proportion of blood volume occupied by red cells, typically around fortythree percent. It varies by patient and it changes how blood separates, which is one reason an identical protocol yields different results in different people.
Figure
The red cell fraction
Figure. Haematocrit is the share of blood volume occupied by red cells, typically around forty three percent. A patient with a high haematocrit yields less plasma from the same draw, and therefore fewer platelets to concentrate.
In practice
A high haematocrit means a larger red cell fraction and a smaller plasma fraction, so the same draw volume produces less plasma and therefore fewer platelets to concentrate.
See also