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HelpTest Code IMML56 Anti Xa Heparin (Unfractionated)
Clinical Information
Used to monitor treatment with unfractionated (standard) heparin.
Synonym
- AXHEP
- UFH
- Heparin assay
- Unfractionated heparin
Specimen Required
Preferred Container/Tube: 3.2% Citrate Blue Top - 2.7 mL
Specimen Volume: 2.7 mL
Acceptable Container/Tube: 3.2% Citrate Blue Top - 1.8 mL
Specimen Volume: 1.8 mL
Platelet poor plasma (PPP):
Specimen Volume: 2 - 1 mL aliquots platelet poor plasma (PPP)
Specimen Minimum Volume: 1 - 1 mL aliquot platelet poor plasma (PPP)
Specimen Collection Information
Samples from outreach locations must be received as frozen plasma.
For sending frozen specimens, process specimens immediately upon collection. Centrifuge capped specimen tube at a speed and time required to consistently produce platelet-poor plasma (platelet count <10 K/uL). Check cells for clot. Do not send for testing if the sample is clotted. Transfer plasma into 2 plastic aliquot tubes and freeze. DO NOT transport until specimens are completely frozen.
Note: All specimens transported as frozen plasma must remain frozen in transit.
Specimen Stability Information
Ambient:
Whole blood: 1 hours
Platelet poor plasma: 2 hours
Frozen:
Platelet poor plasma: PPP removed from the cells and frozen at -20°C or ideally -70°C.
Rejected Due To
- Ambient WB specimens >1 hour old
- Ambient PPP specimens >2 hours old
- Clotted specimens
- Underfilled or overfilled tube
- Hemolysis
- Icterus
- Lipemia
Reference Values
0.30-0.70 IU/mL
Cautions
Test is not indicated if the patient is receiving low molecular weight heparin or any other Anti-Xa drug.
Method Description
Chromogenic measurement at 405nm
Performing Lab
Clinical Lab UH
Day(s) Performed
Monday through Sunday
Report Available
Same day/1 day
Reporting Name
Anti Xa Heparin (Unfractionated)
CPT Code Information
85520
LOINC Code Information
31159-7