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Rivaroxaban

Item Value
Available Stat? No
Test code RVX
Performed by Parnassus Hematology
In House Availability Monday - Friday 0800-1600
Method Chromogenic anti-Factor Xa
Collection Instructions 1. Check the expiration date on the label of the blue top vacutainer before drawing the patient.

2. For blood collection in a sodium citrate blue top, the tube must be filled to above the Minimum Fill Indicator on the tube. It is crucial to wait and allow the tube to stop filling before removing it from the needle.

3. With use of a butterfly needle, draw about 1 cc using a separate blue top to remove air from tubing, discard the first tube and then draw a second blue top tube filled to the full extent of the vacuum.

4. Tubes should not be filled past the Maximum Fill dashed line by either using a syringe or removing the tube cap.
Container type Blue (2.7 mL) or Lt. Blue (1.8 mL) top filled to full extent of vacuum
Amount to Collect 2.7 or 1.8 mL blood
Sample type Citrated plasma
Preferred volume 1 mL plasma
Min. Volume 0.5 mL plasma
UCSF Rejection Criteria Samples collected in outdated blue top vacutainer.

Over-filled or under-filled tubes may be rejected
Processing notes Deliver immediately to Hematology for processing.
Units ng/mL
Normal range See additional information
Critical value > 500 ng/mL
Synonyms Xarelto; Monitoring Anticoagulation; Anti Factor 10a; Anti Factor Xa
Stability Room temperature 4 hours
Turn around times 1-3 days
Additional information Although the manufacturer of rivaroxaban (Xarelto, Bayer Healthcare AG) does not recommend routine monitoring, the Einstein-DVT-Dose-Ranging Study (Blood 2008;112:2242-2247 has found the following typical drug levels in patients taking rivaroxaban:

20mg QD 30 mg QD 40 mg QD
Trough ng/mL 19-60* 24-83* 31-96
Peak ng/mL 175-360 184-399 205-564

*At UCSF, the limit of detection for rivaroxaban is 25 ng/mL.

In this study, trough samples were taken just prior to drug administration and peak levels were drawn 2-6 hours after last intake.

In addition, Laboratory assessment of rivaroxaban: a review (Samama et al. Thrombosis Journal 2013, 11:11) found the following results typical in patients taking rivaroxaban following major orthopedic surgery:

2.5 mg bid 5 mg bid 10 mg bid 20 mg bid 30 mg bid
Peak (ng/mL) 53 86 180 299 400
Trough (ng/mL) 8* 11* 38 68 160

*At UCSF, the limit of detection for rivaroxaban is 25 ng/mL.

The appropriate therapeutic range will vary with the disease and the treatment intensity desired. An overview of recommendations is available in the laboratory manual for reference purposes only. Recommendations for rivaroxaban therapy and monitoring are available through the Hematology consultation services: for adults pager 443-4276, for pediatrics pager 443-6966.

For additional information please see:

Click here for Blood article

Click here for Thrombosis article
CPT coding 80299
LDT or Mod FDA? Yes
Last Updated 8/22/2017 5:29:39 PM
Entry Number 1657
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