What is the term for the percentage of total blood volume that consists of erythrocytes?

The term that refers to the percentage of total blood volume that consists of erythrocytes (red blood cells) is hematocrit. Hematocrit is typically measured as part of a complete blood count (CBC) and is expressed as a percentage. For instance, a hematocrit of 40% means that 40% of the volume of blood is made up of red blood cells. This measurement is crucial for assessing various health conditions, including anemia and polycythemia, which relate to the levels of red blood cells in the bloodstream.

Hemoglobin, while related to erythrocytes, is a protein within the red blood cells that carries oxygen; it measures the amount of this protein but does not reflect the percentage of red blood cells in the total blood volume. Hematoma refers to a localized collection of blood outside of blood vessels, usually in tissue, and gout is a type of arthritis characterized by sudden, severe attacks of pain, redness, and tenderness in joints due to elevated uric acid levels. These terms do not pertain to the measurement of erythrocytes in blood volume.