Blood Smears
Blood film
Also known as blood smear, this is used to perform: - Differential White Blood Cell (WBC) count - Estimated Platelet Count - Evaluate the morphologic features of WBCs, red blood cells (RBCs), and platelets ***should be created, even when using an automated hematology analyzer***
Preparing a Blood Film
Below are the steps for what? - Use newer slide - Wipe slide with Kimwipe to remove any oily finish - Place drop pf blood near frosted end slide - Use plasma (from a purple top tube) - Write patient information on frosted end (if available) or one end if unfrosted: wax pencil or regular pencil is preferred, Sharpie will dissolve in alcohol-based stain - Place the clean end of a second slide against the surface of the first slide at ~ a 30-degree angle and drawn back into the drop - Once the blood is spread along the width of the spreader slide, push forward in a steady, even and rapid motion - air-dried by gently waving or let it sit propped up at an angle
Why blood smears are important
Several abnormalities can be missed and not reported by automated systems - Nucleated RBCs - RBC abnormalities - Toxic granulation/changes in cells - Platelet clumps - Target cells - Hemoparasites
Angles for abnormal samples
Some samples will have different consistencies, depending on the patient's condition, which will change how you approach the smear. Figure A - A large angle is used for anemic blood (thinner) Figure B - A small angle is used for hemoconcentrated blood (thicker)
A large angle
What angle would be used to create a blood film for anemic (thinner) blood?
A small angle
What angle would be used to create a blood film for hemoconcentrated (thicker) blood?
RBC abnormalities, nucleated RBCs, toxic cells, target cells, platelet clumps, hemoparasites
What can be seen on a blood smear and not on an automated machine?