Blood smear preparation
Evaluation of a blood smear is important to assess blood cell morphology and abnormalities and to perform a white blood cell differential count if needed. Any haematology sample being sent to an external lab should be accompanied by a blood smear.
A micro-haematrocrit tube should be used to place a drop of well mixed blood towards the end of a microscope slide, in the centre. Another slide being used as a ‘spreader slide’ should be placed in front of the blood spot at an angle of about 30 degrees and drawn backwards until it comes into contact with the blood. This allows the blood to spread out rapidly along the edge of the spreader slide. As soon as the blood has spread out the spreader slide should be advanced smoothly and quickly. As the smear is made a feathered edge should form and at this point the spreader slide can be lifted off. The slide should be allowed to air dry before either being stained or packaged for submission.