(Using Cyanmethamo Globin Method) (Cheesbrough; 2000).
Principle of Test:
Whole blood is diluted 1 in 201 in a modified drabkins solution which contains potassium ferricyanide and potassium cyanide. The red cells are haemolysed and the haemoglobin is oxidized by the ferricyanide to methaemoglobin. This is converted by the cyanide to stable cyanmethaemoglobin (Cheesbrough, 2000).
Test Procedure for hemoglobin estimation
Haemoglobin estimation (using cyanmethaemoglobin method).
- I measured carefully 0.02ml of well mixed venous blood and dispensed into 4ml of drabkins solution and mixed very well.
- The wave length of the colorimeter was set at 540nm
- I set the colorimeter to zero level with the drabkin’s solution.
- The absorbance of the sample was read.
- Using the table prepared from the calibration graph I read off the hemoglobin value.
The Blood Film Examination in Hemoglobin Estimation
(for Blood Cell Differential Count)
A small drop of well mixed anticoagulated blood placed on a clean grease free non- scrupulous glass slide allowed to air dried and stained in which all the cells are stained
differently which made it easier for them to be recognized and thus counted
Test Procedure for differential count
- I Placed a drop of blood on the end of a clean dry slide
- Using a clean smooth edged spreader I drew the spreader back to touch the drop of blood and allowed the blood to extend along the edge of the spreader, the drop of blood was spread quickly to make a film about 40 – 50mm in length
- I cleaned the end of the spreader
- Immediately I air – dried the film by waving the slide back and forth
- When completely dried,I stained with leishman stain
- Then examined under the microscope and reported.