Test Code PFA PFA-100 (Platelet Function Analyzer)
Specimen and Container/Tube
Specimen Type: Whole Blood
Preferred Specimen: Light Blue Top Tube, 3.2% Sodium Citrate
Other Acceptable specimens: N/A
Specimen Handling and Transport Instructions
UCMC Onsite Instructions:
Collect specimen per standard collection procedure and send to laboratory immediately.
NOTE: Once each blue top tube is completely filled, gently invert the sample tube at least five times to ensure complete mixing of the contents.
UCMC Offsite and UC MedLab Outreach Instructions:
- Whole blood sample must arrive in the laboratory within three hours of specimen collection.
- Draw two blue top tubes.
- Once each blue top tube is completely filled, gently invert the sample tube at least five times to ensure complete mixing of the contents.
- Do not centrifuge samples. Centrifuged samples will be rejected.
- Send samples Room Temperature. Refrigerated or frozen samples will be rejected.
Rejection Criteria
- Common specimen rejected situations include: incorrect specimen type, insufficient volume, missing or incomplete specimen identifiers, incorrect specimen transport, or specimens outside stability limits.
- Specimens that have wrong ratio of blood to anticoagulant (fill volume), clotted or grossly hemolyzed.
Reference Values
Test |
Age |
Sex |
Reference Range |
Collagen/Epinephrine |
ALL |
ALL |
80 - 190 seconds |
Collagen/ADP |
ALL |
ALL |
60 - 122 seconds |
Critical Values
Analyte |
Unit |
Low |
High |
Age |
N/A |
N/A |
N/A |
N/A |
N/A |
CPT Codes
85576 X2
LOINC Codes
24471-5, 24472-3
Volume
Preferred Volume: Two Blue Top Tubes, 3.2% Sodium Citrate
Minimum Volume: Two Blue Top Tubes, 3.2% Sodium Citrate
Specimen Stability
Storage Temperature |
Stability |
Room temperature |
4 hours |
Refrigerated |
not acceptable |
Frozen |
not acceptable |
Collection Instructions
Collect specimen per standard laboratory collection procedures.
NOTE: Once each blue top tube is completely filled, gently invert the sample tube at least five times to ensure complete mixing of the contents.
Test Components
Collagen/Epinephrine
Collagen/ADP
Clinical Indications
Screening for disorders of primary hemostasis (von Willebrand disease, platelet dysfunction), either congenital or acquired
Methodology
Platelet aggregation
Additional Information
The test should not be ordered if hematocrit is below 30% and/or platelet count is below 100,000/uL.
3.2% sodium citrate light blue top tubes must have 9 to 1 ratio of blood to anticoagulant
Turnaround Time
Turnaround times are relative to the time the specimen is received in the test laboratory.
STAT Turnaround Time: N/A
Routine Turnaround Time: 4 hours
Testing Schedule: 24/7
Synonyms/Keyword Search
PFA-100, Epi, ADP, Epinephrine, Primary hemostasis screen
Last Review Date
05/28/2024