LOW MOLECULAR WEIGHT HEPARIN ASSAY

Mnemonic

LMWH

Synonym

Anti-Factor Xa

Specimen Collection Requirements

Collect

Two light blue (3.2% Buffered Sodium Citrate) top tubes

Handling

Freeze plasma within 2 hours of collection.

Preferred Volume

Two 1.0 mL aliquots

Minimum Volume

One 1.0 mL aliquot

Transport

Frozen at -20 degrees Celsius.

Rejection Criteria

Samples not processed and/or transported as required, clotted samples, samples collected in containers other than 3.2% Buffered Sodium Citrate, tubes filled less than 90%, samples from patients with a Hematocrit greater than 55%, hemolyzed samples due to ex-vivo causes (i.e., difficult draw, poor sample draw), whole blood samples that were frozen before processing

Stability

Whole blood stable at room temperature for one hour un-centrifuged and 2 hours centrifuged: Plasma stable one month frozen at -20 degrees C.

Testing Information

Note

The type of heparin, unfractionated or specified brand of low molecular weight heparin (i.e., Enoxaparin, Lovenox), the patient is receiving must be noted. The specific type must be provided to perform the testing. If low molecular weight heparin is being used, the brand name, last dose and mode of infusion must be on all orders.

Performed

7 days per week.

Method

Chromogenic

Referral Lab

Legacy Laboratory Services

Reference Values

Reference Values

Preliminary Therapeutic Guidelines for LMW Heparin Levels: Twice-a-Day Subcutaneous: 0.5-1.1 Units/mL Once-a-Day Subcutaneous: 1.0-2.0 Units/mL Optimum sampling time is 4hrs post-injection. Methodology: Anti-Xa Chromogenic assay on the Stago Compact

CPT Codes

85520

Last Updated: Wednesday, April 4, 2018 09:40:32 AM