blood practical-1

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-Micro-hematochematoc

rit rit analyzeranalyzer

Coult

Coulter er Count

Counterer

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 The number of disturbances = number disturbances = number of particlesof particles

The amount of The amount of disturbance = volume disturbance = volume of particlesof 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 ValuesMaleMale FemaleFemale AverageAverage

RBCRBC 4.5-6.5 4.5-6.5 x10x1066//l l

3.8-5.8 3.8-5.8 x10x1066//ll

4.7–6.5 4.7–6.5 x10x1066//ll

WBCWBC 4 – 11 4 – 11 x10x1033 / /ll

4 – 11 4 – 11 x10x1033 / /ll

4 – 11 4 – 11 x10x1033 / /ll

HBHB 13-18 13-18 g/dlg/dl

11.5-11.5-16.5 g/dl16.5 g/dl

13 –18 13 –18 g/dlg/dl

PlateletPlatelet 150-150-400x10400x1033 / /ll

150-150-400x10400x1033 / /ll

150-150-400x10400x1033 / /ll

Clinical application

1. RBC = aneamia2. RBC = polycythemia3. WBC = leucopenia4. WBC = leucocytosis5. Platelets =

thrombocytopenia6. Platelets =

thrombocytosis

Measurement of Heamatocrit

Collect blood sample in heparinized capillary tube

Centrifuge

Read by heamatocrit reading scale

Normal value

Male Female Average

PCV % 40-54 35-47 35-54

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= 80-100 fl (fimtolitre ?)

Mean corpuscular heamoglobin (MCH)= Average weight of Hb in RBC. MCH= Hb X 10/RBC Normal= 27-31 pg

(picogram?)

Calculation of RBC indices

Mean corpuscular heamoglobin concentration (MCHC)= Concentration of Hb in 100ml of

RBCs. MCHC= Hb X 100/Hct Normal= 32-36 g/dl

Clinical Application

Helps in the diagnosis of aneamia.