Specimen Requirements

Citrated blood or plasma and EDTA blood are required for this test.

Citrated Blood or Plasma for APTT, D-Dimer, Fibrinogen, and PT

Submit only 1 of the following specimens:

Riverside Inpatients and Riverside Campus draw sites:

Testing must be performed within 4 hours of draw if submitting unprocessed whole blood.

Draw 3 full, light blue-top (citrate) tubes; and send citrated whole blood. Invert several times to mix blood. Forward unprocessed whole blood promptly at ambient temperature only. Do not refrigerate.

Note:

1. Gross hemolysis, lipemia, and icteric specimens may affect results.

2. Indicate whole blood on request form.

3. Label specimens appropriately (citrated whole blood for APTT, D-dimer, fibrinogen, and PT).

Outpatients/Outreach Clients:

Plasma-Frozen

Draw 3 full, light blue-top (citrate) tubes. Spin down, remove plasma, spin plasma again, and place citrated platelet-poor plasma into 3 plastic vials each containing 1 mL. (Glass vial is not acceptable.) Pour-off vials should be no more than 2/3 full. Send specimen frozen.

Note: 1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.

2. Gross hemolysis, lipemia, and icteric specimens may affect results.

3. Indicate plasma on request form.

4. Label specimens appropriately (citrated plasma for APTT, D-dimer, fibrinogen, and PT)

EDTA Blood for Platelet and Schistocyte Smear

Draw a full, lavender-top (EDTA) tube; and send EDTA whole blood. Invert several times to mix blood. Forward unprocessed whole blood promptly at ambient temperature only. Do not refrigerate.

Note:  Label specimen appropriately (EDTA whole blood for platelet and schistocyte smear).