Test Code HEPTP Heparin Anti-Xa, Plasma
Ordering Guidance
To test for the presence of inhibitors directed against factor X (FX), order 10INE / Factor X Inhibitor Evaluation, Plasma.
Specimen Required
Specimen Type: Platelet-poor plasma
Collection Container/Tube: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. For complete instructions see Coagulation Guidelines for Specimen Handling and Processing.
2. Centrifuge, aliquot plasma, and centrifuge plasma again.
4. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
Additional Information: Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
Useful For
Measuring heparin concentration:
-In patients treated with low-molecular-weight heparin preparations
-In the presence of prolonged baseline activated partial thromboplastin time (APTT) (eg, lupus anticoagulant, "contact factor" deficiency, etc)
-When unfractionated heparin dose needed to achieve desired APTT prolongation is unexpectedly higher (>50%) than expected
This test is not useful for monitoring therapy with the heparinoid "danaparoid."
Method Name
Chromogenic Method
Reporting Name
Heparin Anti-Xa, PSpecimen Type
Plasma Na CitSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Na Cit | Frozen (preferred) | 14 days | |
Ambient | 2 hours |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Gross icterus | OK |
Reference Values
Adult Therapeutic Range
UFH therapeutic range: 0.30-0.70 IU/mL
(6 hours following initiation or dose adjustment)
LMWH therapeutic range: 0.50-1.00 IU/mL for twice daily dosing*
LMWH therapeutic range: 1.00-2.00 IU/mL for once daily dosing*
LMWH prophylactic range: 0.10-0.30 IU/mL
*Sample obtained 4 to 6 hours following subcutaneous injection
Performing Laboratory
MCHS- MankatoTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
85520
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
HEPTP | Heparin Anti-Xa, P | 3274-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
HEPTP | Heparin Anti-Xa, P | 3274-8 |
Day(s) Performed
Monday through Sunday