RED BLOOD CELL COUNT
Introduction and principle:An RBC count is a blood test that tells how many red blood cells
per cubic millimeter of blood.
Normal RBC values at various ages are :
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Newborns:4.8-7.2 millions
Adult:( male) :4.6-6.0 millions
(Females): 4.2-5.0 millions
Pregnancy : slightly lower than normal
Children: 3.8-5.5 millions
Objectives :To do red cell count of a provided sample of blood using
Neubauer’s counting chamber.
Methods:1. Manual methods
2. Electronic method
Manual RBC cont
Materials and Instruments
Whole blood,using EDTA or heparin as an anticoagulant.
Using capillary blood.
Hayem’s solution:Hgcl2 0.05g, NaSO4 2.5g, NaCl 0.5g and
distilled water 100ml.
RBCpipette
Hemocytometer (Neubauer’s counting chamber) with
coverslip.
Microscope.
Lancet.
Alcohol 70%.
Pipette rotator
Aspirator connected to a faucet with running water.
Proceedure
 Wipe finger with cotton soaked with alcohol, with a
sterile lancet do small prick on the finger tip.Use pipette.
Aspirate blood to 0.5.
 Aspirate diluting Hayem’s solution to the 101 mark.
 Hold the pipette horizontally and role it with both hands
between finger and thumb.
 Touch the tip of the pipette on the surface of the
counting chamber 45 degree.
 Place the chamber on the stage of the microscope and
allow 2 minutes for the cell to settle.
 Scan the counting area with 10x objective lens.
 Use 45x objective, include all cells lying on the upper and
left lines of any sequare, omit the cells on the lower and
right- hand lines.
 Count the cells in five groups of 16 small sequares i.e 80
small sequares.
Calculation:The total number of red cells/c.mm=NX 10 000.
N is the number of red cells found in 80 squares.
The result :5000 000 RBC/C.mm
Calculation:The total number of red cells/c.mm=NX 10 000.
N is the number of red cells found in 80 squares.
Discussion:The primary function of the RBC, or erythrocytes, is to carry
oxygen from the lung to body tissues and to transfer carbon
dioxide from the tissues to the lungs. Oxygen transfer is
accomplished by the hemoglobin contained in red blood cells.
Why the test is performed
This test can help in diagnosis anemia and other conditions
affecting RBC.
The RBC count is almost always part of the CBP (complete blood
picture).
Increased in numbers of RBC called polycythemia it is due to:
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Congenital heart disease
Cor pulmonale
Dehydration
Pulmonary fibrosis
Polycythemia vera.
Decreased in numbers of RBC is due to : Anemia
 Bone marrow failure
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Erythropoietin deficiency(2ndry to kidney disease)
Hemolysis(RBC destruction)from transfusion reaction
Hemorrhage
Leukemia
Multiple myloma
Nutritional deficiencies of
(Iron,Copper,Folate,Vit.B12,B6)