Objectives 1. Methods used to measure the different hematological values, and compare it with the normal values. 2. The calculation of RBC indices, their normal values and their importance in diagnosis of different types of anemia. 3. Method used for determination of PCV (Hct) value.

1. Obtain CBC (RBCs, WBC, & platelets). 2. Determination of hemoglobin concentration. 3. Determination of packed cell volume (PCV) hematocrit. 4. Calculation of red blood cell indices. Micro- hematocrit analyzer Coulter Counter

General Principle  It counts and measures the sizes of particles (cells) by detecting and measuring the changes in electrical resistance when a particle in a conductive liquid pass through a small aperture.

An electrical current is passing through the aperture This current is disturbed when a cell passes through the aperture The number of disturbances = number of particles The amount of disturbance = volume of particles

Steps 1. Collect blood sample in anticoagulated glass tube. 2. Diluted by device and it will count RBCs. 3. A lytic reagent will be added to blood sample. 4. Lysis of RBCs for WBC count and Hb measurement.

Normal Values MaleFemaleAverage RBC x10 6 /  l x10 6 /  l 4.7–6.5 x10 6 /  l WBC 4 – 11 x10 3 /  l HB g/dl g/dl 13 –18 g/dl Platelet x10 3 /  l

Clinical application 1.  RBC = aneamia 2.  RBC = polycythemia 3.  WBC = leucopenia 4.  WBC = leucocytosis 5.  Platelets = thrombocytopenia 6.  Platelets = thrombocytosis

Measurement of Heamatocrit Collect blood sample in heparinized capillary tube Centrifuge Read by heamatocrit reading scale

Normal value MaleFemaleAverage PCV %

Clinical Application   Hct (PCV):   RBC (polycythemia) ;   plasma volume (hemo-concentration)   Hct (PCV):   RBC (anemia),   plasma volume (hem-dilution)

Calculation of RBC Indices  Mean corpuscular volume (MCV)=  Average RBC volume.  MCV= Hct X 10/RBC  Normal= fl (fimtolitre ?)  Mean corpuscular heamoglobin (MCH)=  Average weight of Hb in RBC.  MCH= Hb X 10/RBC  Normal= pg (picogram?)

Calculation of RBC indices  Mean corpuscular heamoglobin concentration (MCHC)=  Concentration of Hb in 100ml of RBCs.  MCHC= Hb X 100/Hct  Normal= g/dl

Clinical Application  Helps in the diagnosis of aneamia.