Which test measures the proportion of red blood cells in blood?

Which test measures the proportion of red blood cells in blood?

• A. Hematocrit
• B. Mean corpuscular volume
• C. Total protein
• D. Packed cell volume (PCV)

Answer: (D)

The proportion of red blood cells in blood is captured by measuring how much of the blood’s volume is made up of erythrocytes. This is done by centrifuging a blood sample and expressing the height (or volume) of the packed red cell layer as a percentage of the total sample — the packed cell volume. PCV, sometimes called hematocrit, is the label for this same measurement in many veterinary labs, giving the direct percentage of blood that is red blood cells. Mean corpuscular volume, on the other hand, reflects the average size of the red blood cells, not how much of the blood is occupied by them. Total protein measures plasma proteins, not cells.

The proportion of red blood cells in blood is captured by measuring how much of the blood’s volume is made up of erythrocytes. This is done by centrifuging a blood sample and expressing the height (or volume) of the packed red cell layer as a percentage of the total sample — the packed cell volume. PCV, sometimes called hematocrit, is the label for this same measurement in many veterinary labs, giving the direct percentage of blood that is red blood cells.

Mean corpuscular volume, on the other hand, reflects the average size of the red blood cells, not how much of the blood is occupied by them. Total protein measures plasma proteins, not cells.