Enoxaparin Assay (Anti Xa)
Label Mnemonic: | ENOX |
Epic code: | LAB316 |
Downtime form: | Doctor/Provider Orders - Pathology Core and Specialty Care Nursery |
Hemostasis/Thrombosis
6240 RCP
356-3573
6240 RCP
356-3573
Specimen(s):
Citrated Plasma More information
Collection Medium:
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Light Blue top tube 1.8 mL (Na Citrate) |
Minimum:
Full draw; 1.8 mL in light blue-top (3.2% sodium citrate) tube. Mix well.
Delivery Instructions:

Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around
Time:
2 hours (upon receipt in laboratory)
Reference Range:
The therapeutic range for low molecular weight heparins (LMWH) varies with the type and manufacturer, but for adults is typically 0.4 – 1.1 U/mL. For adults, the target range for VTE prophylaxis is 0.2 – 0.4 U/mL.
Methodology:
Anti Xa activity by chromogenic substrate without antithrombin supplementation.
Assay updated to Siemens Innovance reagent on 03/05/19.
CPT Code:
85520
See Additional Information:
Hemolysis Chart
Phlebotomy Tubes and Order of Draw
Impact of Common Anticoagulants on Coagulation Tests
Hemolysis Chart
Phlebotomy Tubes and Order of Draw
Impact of Common Anticoagulants on Coagulation Tests
High doses of low molecular weight heparin with low anti-Xa results could be due to low antithrombin activity.