LAB - PACKED CELL VOLUME TEST (PCV)

Introduction:

Haematocrit is also known as Packed Cell Volume (PCV). The packed cell volume (PCV) is the measure of the ratio of the volume occupied by the red cells to the volume of whole blood in a sample of capillary, venous, or arterial blood. The word hematocrit means “to separate blood”, which underscores the mechanism of the test because the plasmas and blood cells are separated by centrifugation.

Objective:

To measure the ratio of the volume occupied by red blood cells to the volume of whole blood in a sample of venous blood.

Equipments:

1. Microhaematocrit tube
2. Micorhaematocrit centrifuge
3. EDTA venous blood
4. Plastercene
5. Microhaematocrit reader

Procedure:

1. The blood is mixed well.
2. The blood is filled into the haematocrit tube until it is 4/5 of the blood.
3. The other end of the capillary tube is sealed with plastercene.
4. The capillary tube is placed into the microhaematocrit centrifuge.
5. The capillary tube is centrifuged for 5 minutes for 12000 rpm.
6. Read and record the results by using microhaematocrit reader.

Questions:

1. Define haematocrit.
2. What is the other term for haematocrit?
3. Name three layers of centrifuged blood.
4. Why it is important to read the microhaematocrit soon after the centrifuge stops?