Test Code LAB318 Platelet Function Assay (PFA)
Test Name Alias
Platelet Function Assay | Plt Function Assay | PFA | 4323
Collection Instructions
Specimen Collection: Blood
Container(s): 4.5 mL Blue top (3.2% Na. Citrate) and Lavender top (EDTA)
Preferred Volume to Collect: Tubes must be full
Capillary collect ok: No
Microtainer acceptable: No
Collection Instructions:
-
Please indicate anticoagulant therapy.
-
Detailed instructions: Blue Citrate Tube
-
Non-tramatic venipuncture should be performed using a 21 guage needle.
- Avoid leaving the tourniquet on the patient’s arm for an extended period prior to collection.
- If specimen is collected using a line, then 5.0 mL waste is required, this waste can be given back.
- Tubes must be full. Do not over fill or under fill; look for the fill indicator lines.
- Gently invert 8 - 10 times to mix anticoagulant with blood.
- Testing must be performed within 4 hours of collection.
Processing Instructions (Laboratory, Outpatient or Off-site collection)
Processed Specimen: Whole Blood
Centrifuge/Spin: No
Aliquot: No
Processing Instructions:
- Testing must be performed within 4 hours of collection
- Do not refrigerate/freeze or centrifuge specimen
- Please call for STAT courier pick-up and direct specimen to the Spectrum Health Regional Laboratory (35 Michigan, Grand Rapids)
Transport Temperature:
- Specimen must be kept at ambient/room temperature.
Specimen Stability
Ambient: 4 hours (whole blood state)
Refrigerate: not acceptable
Frozen: not acceptable
Laboratory Retention: 24 hours
Test Frequency
Available 24 hours, usual TAT 4 hours.
Reference Range
PFA Collagen/ADP
60 – 110 second(s)
PFA Collagen/Epi
80 – 180 second(s)
Closure time above the laboratory reference range could reflect reduced platelet function caused by hematocrit levels <35% or platelet counts <150,000/mL
Clinical Information
Mandatory Reflex Information
- Platelet Function Assay (PFA 100) with Collagen/Epinephrine results greater than 180 seconds, Collagen/ADP test will be performed.
Performing Department
Coagulation
Performing Department Laboratory Location
Spectrum Health Regional Laboratory (SHRL), Grand Rapids, MI
Methodology
The PFA-100® is an instrument and test cartridge system in which the process of platelet adhesion and aggregation is simulated in vitro mimicking injured endothelium. The time necessary to block a membrane coated with collagen and epinephrine or collagen and ADP is measured and called closure time.
CPT
85576 x2
CDM Code
4098454
Interface Order Alias
10766
Mayo Access Code
SHO4323
LOINC
PFA Collagen/Epi: 24471-5
PFA Collagen/ADP: 24472-3
PFA Hematocrit: 4544-3
PFA Platelet Cnt: 777-3
Reviewed Date
7/13/2016