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Chromogenic Substrate Assay
The Rivaroxaban assay is a chromogenic assay for the determination of the activity of Rivaroxaban (Xarelto) in plasma and for the monitoring of Rivaroxaban therapy.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 1 hour of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a plastic vial, and freeze the specimen within 1 hour 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.