Rivaroxaban Assay (Anti Xa)
| Label Mnemonic: | RVRXB |
| Epic code: | LAB8858 |
| Order form: | Laboratory Requisition |
| Supply order: | Supply Order Form |
| Billing: | Billing Policies |
| CPT code: | 85130 |
Specimen(s):
Plasma More information
Collection Medium:
 | or |  |
| Light Blue top tube 2.7 mL (Na Citrate) | Light Blue top tube 1.8 mL (Na Citrate) |
Minimum:
Full draw; 2.7 mL light blue top or 1.8 mL light blue top (mix well)
Testing
Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around
Time:
1-2 hours (upon receipt in laboratory)
Comments:
This assay is not specific for rivaroxaban. Any drug with anti-Xa activity, such as heparin, enoxaparin, apixaban, edoxaban, or betrixaban will cross-react to give a measurable concentration for rivaroxaban.
A therapeutic range has not been established for rivaroxaban. Therapeutic ranges derived from published literature are variable and are not well correlated with safety, efficacy, or clinical outcomes. Plasma concentrations of rivaroxaban are as follows (mean +/- 2 SD) from study referenced below:
10 mg (once daily dose):
Peak 124.6 ng/mL (91.4 - 195.5)
Trough 9.1 ng/mL (1.3 - 37.6)
20mg (once daily dose)
Peak 222.6 ng/mL (159.6 - 359.8)
Trough 9.1 ng/mL (4.3 - 95.7)
Peak concentrations were obtained 3 hr after dose.
Plasma levels should not be used to determine if a patient is adequately or overly anticoagulated. The use of this test should be limited to the following:
This testing was developed, and its performance characteristics determined by the University of Iowa Emory Warner Pathology Laboratories. It has not been cleared or approved by the FDA. The laboratory is regulated under CLIA as qualified to perform high-complexity testing. This test is used for clinical purposes. It should not be regarded as investigational or for research.
References:
Mueck W, et al Thromb Haemost 2008;100(3):453-461
Douxfil J, et al J Thromb Haemostat 2018;16:209-219
Wright C, et al Int J Lab Hematol 2017;39:31-36
Samuelson BT, et al Blood Rev 2017;31:77-84
Instrumentation changed from BCS-XP to CS-5100 on 12/16/2019.
A therapeutic range has not been established for rivaroxaban. Therapeutic ranges derived from published literature are variable and are not well correlated with safety, efficacy, or clinical outcomes. Plasma concentrations of rivaroxaban are as follows (mean +/- 2 SD) from study referenced below:
10 mg (once daily dose):
Peak 124.6 ng/mL (91.4 - 195.5)
Trough 9.1 ng/mL (1.3 - 37.6)
20mg (once daily dose)
Peak 222.6 ng/mL (159.6 - 359.8)
Trough 9.1 ng/mL (4.3 - 95.7)
Peak concentrations were obtained 3 hr after dose.
Plasma levels should not be used to determine if a patient is adequately or overly anticoagulated. The use of this test should be limited to the following:
1. Measurement of anti-Xa activity in patients undergoing emergent/urgent surgical procedures or with life threatening bleeding associated with rivaroxaban use 2. Assessment of level in a patient who is expected to have been non- adherent/non-compliant
This testing was developed, and its performance characteristics determined by the University of Iowa Emory Warner Pathology Laboratories. It has not been cleared or approved by the FDA. The laboratory is regulated under CLIA as qualified to perform high-complexity testing. This test is used for clinical purposes. It should not be regarded as investigational or for research.
References:
Mueck W, et al Thromb Haemost 2008;100(3):453-461
Douxfil J, et al J Thromb Haemostat 2018;16:209-219
Wright C, et al Int J Lab Hematol 2017;39:31-36
Samuelson BT, et al Blood Rev 2017;31:77-84
Instrumentation changed from BCS-XP to CS-5100 on 12/16/2019.
Methodology:
Anti Xa activity by chromogenic substrate
Sample
Processing:
Centrifuge at a speed and time necessary to get barrier separation of plasma/serum and cells within 1 hour of collection.
Separate plasma into plastic container and cap (glass is not acceptable).
Centrifuge a second time to ensure platelet poor plasma and separate plasma into a new, labeled plastic tube, cap.
Label transport tube with two patient identifiers, date and time of collection.
Separate plasma into plastic container and cap (glass is not acceptable).
Centrifuge a second time to ensure platelet poor plasma and separate plasma into a new, labeled plastic tube, cap.
Label transport tube with two patient identifiers, date and time of collection.
Sample
Storage:
Freeze specimen immediately.
Transport
Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place requisition into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container to maintain frozen temperature.
Place requisition into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container to maintain frozen temperature.
CPT Code:
85130