This test requires three samples:
1. 1.0 mL 3.2% citrated plasma - blue top tube, (BTT) used for PT, APTT, and FIB.
2. 1 mL 3.2% citrated platelet poor plasma - blue top tube, (BTT) used for D-dimer.
3. 2 mL EDTA whole blood - lavender top tube, (LTT) used for platelet determination.
Minimum volume:
1. 1.0 mL 3.2% citrated plasma - blue top tube, (BTT)
2. 0.5 mL 3.2% citrated platelet poor plasma - blue top tube, (BTT)
3. 1 mL EDTA whole blood - lavender top tube, (LTT) and 2 unfixed smears
Processing Instructions:
Blue top tubes:
- Must be drawn to the fill line.
- Invert tubes completely 3-4 times to mix.
- Do not shake.
First blue top tube:
- Centrifuge at 3000 rpm for 10 minutes with the brake OFF as soon as possible after collection.
- Perform testing within one hour of sample collection or separate citrated plasma for storage.
- Use plastic pipette to transfer top half of plasma to polypropylene tube.
- Avoid platelet contamination.
- Cap tightly.
EDTA lavender top tube:
-Test should be performed within 24 hours of collection.
- If not performed within 4 hours of collection, two smears should be prepared immediately for use in confirming abnormal counts.