To count the erythrocyte cells, or RBC, diluting fluid was used. Diluting fluid
for RBC is an isotonic solution. This solution keeps the RBC cells unhemolyzed.
The RBC were counted using an improved neubauer chamber, which has an
area of 1 square millimeter and depth of 0.1 mm. It is made up of 400 boxes.
The cells in the 4 corner boxes and 1 box in the middle were counted.
- EDTA: Ethylene diamine tetra acetic acid is used as an anticoagulant.
- RBC diluting solution: This is prepared by dissolving 0.425 gms of NaCl
in 50 mL of distilled water.
- RBC pipette
- Neubauer counting chamber
- Cover glass
Using a syringe, venous blood was drawn and poured into vials containing
anticoagulant (EDTA) and mixed well. With the help of RBC, pipette blood was
drawn up to the 0.5 mark. The tip of the pipette was cleaned with cotton and
RBC diluting fluid was drawn up to the 101 mark. The pipette with blood and
fluid was shaken well, avoiding bubbling, and kept aside for 5 minutes. The
counting chamber was charged using the posture pipette. After charging the
chamber, the cells were allowed to settle down to the bottom of the chamber.
The chamber was placed on the stage of the microscope and using a 45X
objective, the RBC cells in the smallest square were counted.
The normal range of RBC in an adult male is 5–6 million and in a female it
is 4−5.05 million/mm3
. In the case of polycythemia, the number of RBC increases.
This disease is associated with heart disease. A low count of RBC results in
anemia. Polycythemia may be pathologic due to the tumor in bone marrow, and
the number of red cells may reach 11 million per cubic mm of blood.
The present determination of total RBC count shows about ____/mm3
blood, which is nearly equal to normal range.
Number of cells in 1 mm3
Number of cells counted × dilution factor × depth factor /
Area of chamber counted
Number of cells counted × 200 × 10
1/5 = Number of cells counted × 10,000