STEP 6: Draw the top (second) slide back until it touches the blood. The blood will
quickly spread across the surface of contact.
STEP 7: Holding the top slide at a 30 degree angle, push it smoothly and evenly away
from the drop toward the opposite end of the bottom slide until the blood film
"feathers" out. This should be accomplished rapidly, with one motion, before
the blood spreads to the border of the slide.
Figures 2-3a. Preparation of thin blood smears.
STEP 8: The thick film is prepared by constantly stirring the larger drop of blood in a
circular motion with a corner of the clean slide, spreading it to about the size
of a dime. This aids in breaking up the fibrin strands (defibrination); allows
the cells to readily release hemoglobin (dehemoglobination), and prevents
the drop from floating away during the staining procedure. The thick film
should be of such thickness that ordinary printing (newsprint) can barely be
read through it.
Figure 2-3b. Preparation of thick blood smears.
MD0841
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