Low Molecular Weight Heparin Anti Xa Level

Abbrev Code:ALMWH   
Order Code:LAB8133Order Name:Low Molecular Weight Heparin Anti Xa Level
Synonyms:Lovenox Anti Xa Level; Enoxoparin Anti Xa Level; Anti Xa Level; Anti 10A Level; Heparin 10A Level; Heparin Xa Level; Anti Xa Level LMWH; Anti 10A Level LMWH; 10 Level Low Molecular Weight Heparin Anti Xa Level
Methodology:Chromogenic (synthetic substrate) activity assay
CPT Codes: 85520 x1
Turnaround Time:Performed and reported 24 hours/day.
Associated Links:

Specimen Collection and Processing for Coagulation Specimens

Collection Instructions

Optimal Volume:2.7 mL (in 3 mL tube) - filled to fill line on the tube
Minimum\Peds Volume:1.8 mL (in 2 mL tube) - filled to fill line on the tube
Container:Blue Na Citrate, 3.2% - fill to fill line on tube
Collection Instructions:If the patient's hematocrit is >55%, contact laboratory to obtain a special tube. If using a butterfly needle, a waste tube must be collected before the blue top tube.
After Care:If the patient has a coagulation abnormality, apply direct pressure to the puncture site for 10 minutes; apply a pressure dressing. Instruct the patient to leave the bandage on for 12 hours.
Causes for Rejection:Underfilled tubes, overfilled tubes, clotted specimens, specimen collected in 3.8% buffered citrate. Whole blood specimen greater than 2 hours old, or not processed appropriately within 1 hour of collection.

Processing and Shipping

Specimen Processing:Must be processed within 1 hour of collection. See Associated Links for additional processing instructions.
Shipping Instructions:Ship processed plasma on dry ice. Must arrive within 48 hours.
Test Performed at or Referral Lab Coagulation  (Grand Itasca, Lakes, Northland, Range, Ridges, Southdale, UMMC East Bank, UMMC/UMMCH-West Bank, Woodwinds)


Critical Range:>2.00 IU/mL
Therapeutic Range:If collected 4-6 hours after administration:
If administered only once daily with a dose of 1.5 mg/kg: 1.0-2.0 IU/mL.
If administered twice daily with a dose of 1 mg/kg: 0.50-1.0 IU/mL.

If administered twice daily: 0.50-1.0 IU/mL.
Use:Quantitative determination of the plasma levels of low molecular weight (LMWH) heparin by measuring the anti-Xa activity on antithrombin in a competitive assay using a synthetic chromogenic substrate.

Click HERE to Report test errors or omissions.
*If no email program is associated with this computer, please contact:
[email protected] for TestID: 6860"