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Low Molecular Weight Heparin Assay (LMWH or Factor Xa)

Mnemonic:    [Anti Xa]
Name:    Low Molecular Weight Heparin Assay (LMWH or Factor Xa)
Specimen:    2 mL plasma from a FULL sodium citrate Blue top tube. Allow tube to fill to proper capacity. Mix immediately by gentle inversion 4 times.
Room temperature sample must be delivered to the CMMC hematology lab within one hour of collection. If the unspun sample cannot be delivered to the lab in that time period, the patient should be sent to the CMMC Outpatient Phlebotomy area for specimen collection.

Draw 4-6 hours post injection of Lovenox or other low-molecular weight heparin.

Please phone lab before drawing.
Reference Range:    0.50 - 1.10 IU/ml
Processing Info:    The sample must be kept at room temperature prior to centrifugation. Any samples received separated must have been processed in a CAP approved calibrated and documented centrifuge to provide platelet poor plasma.