Peripheral Blood Smear Preparation (F) Flashcards
What are the purposes of peripheral blood smear?
1) Examination of the circulating blood cells under the microscope
2) Correlation the released blood cell counts from automated machines and obtained blood cell counts from manual methods
3) Confirmation of the presence of abnormal blood cells
What are the accepted sxs for PBS for capillary blood and venous or arterial blood in terms of usage of anticoagulant for the blood sx?
Capillary blood: no anticoagulant is needed; if problem persists, EDTA microcollection tubes can be used
Venous or arterial blood: EDTA is the preferred anticoagulant; if PLT satellitosis occurs, Na citrate can be used
What are the accepted sxs for PBS for capillary blood and venous or arterial blood in terms of timing of smear preparation?
Capillary blood: smears should be done immediately after collection
Venous or arterial blood: smears can be made within 4 hrs of blood draw
What are the accepted sxs for PBS for capillary blood and venous or arterial blood in terms of location of smear preparation?
Capillary blood: smears made bedside
Venous or arterial blood: multiple # of slides
What are the accepted sxs for PBS for capillary blood and venous or arterial blood in terms of PLT clumping?
Capillary blood: present if smears are directly made from puncture site or if heparinized microHct tubes are used
Venous or arterial blood: absent
What are the diff methodologies of PBS?
1) Two-cover slip method or Ehrlich’s
2) Two-slide method or wedge
3) Automated methods
What is the procedure (or steps) of two-cover slip method or Ehrlich’s?
1) Get 2 clean cover slips / glasses. Place 1 small drop of blood on the center of the 1st cover slip
2) Position the 2nd cover slip crosswise on top of the 1st cover slip to allow the blood to spread out evenly on the cover slip
3) Pull the 2nd cover slip rapidly and firmly through a horizontal and lateral manner
4) Air-dry the 1st cover slip
What is the procedure (or steps) of two-slide method or wedge?
1) Get 2 clean glass slides. Place 1 small drop of blood on the far end of the 1st glass slide
2) Position the 2nd glass slide at 30 degrees - 45 degrees before the drop of blood on the 1st glass slide to allow the blood to spread out evenly on the vertex
3) Move the 2nd glass slide rapidly and smoothly over the length of the 1st glass slide at a constant angle
4) Air-dry the 1st glass slide
What are the 2 automated methods of PBS?
1) sysmex
2) Beckman Coulter
What are the criteria of a good smear?
1) The film is 2/3 to 3/4 the length of the slide
2) There should be an gradual transition from the thick area to the thin area
3) The film must have a feathery edge that is very slightly rounded and has a rainbow appearance when the slide is held up to the light
4) The film is finger-shaped or tongue-shaped and not bullet-shaped
5) The film has a smooth and even surface free from ridges, waves, holes, streaks, or irregularities
6) The lateral edges of the film are visible
What are the parts of a PBS?
1) Head (application point)
2) Body (thick area)
3) Monolayer (morphology)
4) Tail (feathery edge)
What is the appearance of blood cells in the body of PBS?
Clumped
What is the appearance of the blood cells in the monolayer of PBS?
Good
What is the appearance of the blood cells in the tail of the PBS?
Sparse
Where should reading be done in an PBS?
In the monolayer
What is the resolution for the ff error in PBS:
Error: chipped or rough edge on spreader slide
Choose a spreader slide w/ smooth edges
What is the resolution for the ff error in PBS:
Error: hesitation in forward motion of spreader slide
Maintain contact w/ the 1st slide as you move the 2nd slide in 1 motion
What is the resolution for the ff error in PBS:
Error: spreader slide pushed too quickly
Move the spreader slide rapidly but not too quickly
What is the resolution for the ff error in PBS:
Error: drop of blood too small
Drop of blood should be limited within 2 - 3 mm in diameter; use a disposable dropper or yellow tip
What is the resolution for the ff error in PBS:
Error: drop of blood not allowed to spread across the width of the slide
Wait for the blood to fully spread on the vertex bet 1st slide and 2nd slide before moving the spreader
What is the resolution for the ff error in PBS:
Error: dirt or grease on the slide
Choose a clean 1st slide and a smooth 2nd slide; check if physiological reason is present (elevated lipids)
What is the resolution for the ff error in PBS:
Error: uneven pressure on the spreader slide
Exert constant pressure to spreader slide as you maintain the contact of 1st slide w/ the 2nd slide
What is the resolution for the ff error in PBS:
Error: time delay
Do not wait for the drop of blood to dry before moving the spreader slide
What is the resolution for the ff error in PBS:
Error: very thick smear
Lower the angle of spreader slide; check if physiological reason is present (increased Hct)
