PHLEBOTOMY ALL MODULES
QUESTIONS AND ANSWERS
The Order of Draw - correct answer- the order in which blood
must be collected via additive/color. The order of draw may
change depending on your lab, facility, manufacturer or
workplace procedure. Below is the order of draw with additional
information. Some of these tubes are rarely used in everyday
outpatient labs but it is good for you to know.
additive - correct answer- Nutrient AgarAerobic BEFORE
Anaerobic
mode of action - correct answer- Preserves viability of
microorganisms, grows bacteria
uses - correct answer- Microbiology - aerobes, anaerobes,
fungi, bacteria cultures Requires BUTTERFLY needle and hub.
Yellow- Black Top Tube - correct answer- Additive: Broth
mixtureMode of Action: Preserves viability of
microorganismsUses: Microbiology - aerobes, anaerobes, fungi
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Yellow Top Tube - correct answer- Additive: ACD (acid-citrate-
dextrose) (Solution A or B)
Mode of Action: Complement inactivation *May also go last in
the order of draw
Uses: HLA tissue typing, paternity testing, DNA studies, Blood
Cultures
Light-Blue Top Tube - correct answer- Additive: Sodium citrate
Mode of Action: Forms calcium salts to remove calcium
Uses: Coagulation tests (protime and prothrombin time), full
draw required
Red Top Tube - correct answer- Additive: None
Mode of Action: Blood clots, and the serum is separated by
centrifugation
Uses: Chemistries, Immunology and Serology, Blood Bank
(Crossmatch)
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Gold Top (SST) Tube - correct answer- Additive: Clot Activator
and Thixotropic Gel
Mode of Action: Serum separator tube (SST) contains a gel at
the bottom to separate blood from serum on centrifugation
Uses: Chemistries, Immunology and Serology
Red/Gray Marble Top (SST) Tube - correct answer- Additive:
Clot Activator and Thixotropic Gel
Mode of Action: Serum separator tube (SST) contains a gel at
the bottom to separate blood from serum on centrifugation
Uses: Chemistries, Immunology and Serology
Orange Top Tube - correct answer- Additive: Thrombin
Mode of Action: Quickly clots blood
Uses: STAT serum chemistries
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Light Green Top Tube - correct answer- Additive: Plasma
Separating Tube (PST) with Lithium Heparin
Mode of Action: Anti-coagulates with lithium heparin; Plasma is
separated with PST gel at the bottom of the tube
Uses: Chemistries
Dark Green Top Tube - correct answer- Additive: Sodium
heparin
Mode of Action: Inactivates thrombin and thromboplastin
Uses: For lithium level, use sodium heparinFor ammonia level,
use sodium or lithium heparin
Lavender Top Tube - correct answer- Additive: Dipotassium
EDTA
Mode of Action: Forms calcium salts to remove calcium
Uses: Hematology (CBC) and Blood Bank (Crossmatch);
requires full draw - invert 8 times to prevent clotting and platelet
clumping