Coagulation Factor Xa Inhibition
Factor Xa Inhibition
Heparin (LMWH) Anti-Xa Assay
Heparin, Low Molecular Weight
Low Molecular Weight Heparin
Anti-Xa LMW Heparin
Factor 10a Inhibition
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Chromogenic Substrate Assay
Used to monitor treatment with low-molecular weight heparins: danaproid, enoxaparin, dalteparin, fragmin, lovenox
Normal individuals have no low molecular weight heparin activity.
Target Therapeutic Range:
Enoxaparin 1.0 mg/kg SC twice daily, 5 hours after dose 0.5 - 1.0 IU/mL;
Enoxaparin 1.5 mg/kg SC once per day, 5 hours after dose 1.0 - 2.0 IU/mL;
Enoxaparin 1.0 mg/kg SC once per day
Trough <0.4 IU/mL drawn just prior to next dose.
[bold]Critical value[/bold] is >2.0 IU/mL.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Collect specimen in a blue top 3.2% sodium citrate Vacutainer® tube. Mix by inversion. Specimen should arrive at lab within 23 hours of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a plastic tube, and freeze the specimen within 24 hours of collection. Transport frozen specimen on dry ice. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.