WBC Count (F)

Question 1

What is WBC ct?

Answer 1

It is the # of WBC in 1mm^3 of blood

Question 2

What are the purposes of diluting fluid in WBC ct?

Answer 2

1) It accurately dilutes the blood

2) It produces complete hemolysis of RBCs w/out injury to the WBCs

Question 3

What are the manners of reading in WBC ct?

Answer 3

1) Left to right, then right to left (starting from the top; recommended)
2) Right to left, then left to right (starting from the top)

Question 4

What are the characteristics of a good WBC diluting fluid?

Answer 4

1) Must be a hypotonic solution
2) Must be easily prepared
3) Must be readily available
4) Must be a good preservative
5) Must be cheap

Question 5

What are the WBC diluting fluids?

Answer 5

1) 1-3% Acetic acid w/ Gentian violet
2) 1% HCl
3) Turk’s solution

Question 6

What are the components of 1-3% Acetic acid w/ Gentian violet?

Answer 6

1) Glacial acetic acid: 2 g
2) Gentian violet: 1 mL
3) Distilled H2O: 100 mL

Question 7

What are the components of 1% HCl?

Answer 7

1) HCl: 1 mL

2) Distilled H2O: 100 mL

Question 8

What are the components of Turk’s solution?

Answer 8

1) Glacial acetic acid: 2 mL
2) Methyl violet: 1 mL
3) Distilled H2O: 100 mL

Question 9

What are the mats needed for WBC ct?

Answer 9

1) Anticoagulated blood
2) WBC pipette
3) 1% HCl
4) Aspirator
5) Microscope
6) INCC
7) Thick coverslip
8) Tissue paper

Question 10

What is the general procedure (or steps) of WBC ct?

Answer 10

1) Preparation of diluted blood
2) Filling the counting chamber (charging)
3) Making the ct

Question 11

What is the detailed procedure (or steps) of WBC ct?

Answer 11

1) Preparation of diluted blood
- > aspirate blood up to 0.5 mark of the WBC pipette
- > wipe off the excess blood at the tip of the pipette w/ a clean pc of tissue paper. Make sure that the tissue paper does not touch the opening of the bore
- > place the diluting fluid in a clean transparent container, then immerse the pipette. Use syringe aspiration to draw the diluting fluid up to the 11 mark w/ constant rotation of the pipette. This will ensure proper mixing of the blood and the diluting fluid. This makes 1:20 dilution
- > gradually bring the pipette to a horizontal position and immediately mix the contents. Make sure that the pipette is held securely w/ thumb and the middle finger
2) Filling the counting chamber (charging)
- > place the thick coverslip on top of the INCC. Both the coverslip and counting chamber must be free from dirt, thumbmarks, tissue strands, and the like
- > re-shake the pipette. Discard the first 2-3 drops of the diluted blood from the pipette and carefully and exactly fill or charge the counting chamber by capillary action. This can be achieved by placing the tip of the pipette on the space bet the coverslip and the central platform of the counting chamber. The angle of of the pipette while charging is 30-35 deg
- > let the chamber stand for 5-10 mins to allow the WBCs to settle
- > locate the ruled area for WBC counting by focusing the microscope using LPO
3) Making the ct
- > ct the WBCs seen on the secondary squares designated at W squares w/ an area of 4mm^3
- > a std pattern of counting should be adopted. Count the WBC on the 1st row of the tertiary squares (left to right), then to the 2nd row (right to left), then to the 3rd row counting from left to right, and on the 4th row counting from right to left
- > record the ct on each of the 4 secondary squares making sure that the cell diff bet the squares is 12 or less

Question 12

How to compute WBC ct (what is the formula)?

Answer 12

No. of cells/mm^3 = total no. of cell counted X 50

Question 13

What is the normal value for WBC ct?

Answer 13

5,000 - 10,000/mm^3