haematology Flashcards
what are the steps in making a blood film?
- Apply a small drop of blood from capillary tube to the end of the slide
- Place a smooth, clean edge of the spreader on the slide, just in front of the drop of blood
- Draw the spreader back into the blood at an angle of 30 degrees to the slide. Ensure the blood is evenly spread across the edge of the spreader.
- Push the spreader with an even motion across the length of the slide. The blood film should have a thin feathery edge and take up 1/2 to 3/4 of the slide
- Label with a pencil and allow to air dry
How do you stain a blood film with Modified Giemsa Stain?
- Place dry, labelled blood film slides on a staining rack over the sink
- Flood sides with stain for 2 mins
- Place slides in a couplin jar of distilled water for 4 mins (not rinsing off stain)
- Rinse with clean distilled water to remove surplus stain then air dry
- spread a thin layer of oil over your slide
- examine the blood film under the microscope on low and high power, including 100x using oil
what do neutrophils look like?
branching nuclei, multinucleated
what do lymphocytes look like?
large nucleus, not much cytoplasm
what do monocytes look like?
no defined nuclear membrane
no defined cell membrane
what do eosinophils look like?
lots of granules inside
what do platelets look like?
little dots
how do you do a reticulocyte count?
Make a blood film, no giemsa stain
- examine under 100x objective
- Find a well spread area (approx 200 RBC per field)
- Count the total number of reticulocytes in the field)
- repeat steps for five feilds in total
- calculate percentage of reticulocytes to RBC (average the 5 feilds)
- Assuming a red cell count of 4.0 x 10^12/L calculate the absolute reticulocyte count ( in cells per L)
what is a reticulocyte?
An immature red blood cell
- still has some nucleus
