Test Code APIXA Apixaban, Anti-Xa Assay, Plasma
Specimen Requirements
Specimen Type: |
Whole Blood |
Container Type: |
Blue top: 2.7 mL or 1.8 mL |
Optimal Collection Volume: |
|
Collection Instructions: |
|
Specimen Transport Temperature: |
|
Processing Instructions: |
Outpatient collections
|
Specimen Stability
Specimen Type |
Temperature |
Time |
---|---|---|
Whole blood |
Room Temperature |
1 hour |
Platelet Poor Plasma |
Room Temperature |
24 hours |
Platelet Poor Plasma | Refrigerated 2-8 C | 7 days |
Platelet Poor Plasma |
Frozen at - 20 C |
24 hours |
Specimen Rejection Criteria
- Tube underfilled
- Refrigerated specimen
- Clotted specimen
- Specimen not processed within four hours of collection
Useful For
The measurement of apixaban levels can be useful information in cases where patients may be at risk for major bleeding, for patients experiencing a bleeding episode, perioperative management, or suspicion of apixaban overdose. This apixaban assay should not be used as a stand-alone test and the results should be used in conjunction with other clinical and laboratory findings.
Peak and Trough Apixaban Levels by Dose and Indication
Indication |
Dosage |
|
Apixaban C-max (ng/mL) |
Prevention of VTE: |
2.5 mg Twice Daily |
51 (23-109) |
77 (41-146) |
Prevention Of Stroke and Systemic Embolism: NVAF |
2.5 mg Twice Daily |
79 (34-162) |
123 (69-221) |
5.0 mg Twice Daily |
103 (41-230) |
171 (91-321) |
|
Treatment of DVT, Treatment of PE and Prevention of Recurrent DVT and PE (VTE) |
2.5 mg Twice Daily |
32 (11-90) |
67 (30-153) |
5 mg Twice Daily |
63 (22-177) |
132 (59-302) |
|
10 mg Twice Daily |
120 (41-335) |
251 (111-572) |
Methodology
The Apixaban, Anti-Xa assay is performed on the Instrumentation Laboratory ACL TOP Family using the HemosIL Liquid Anti-Xa kit. The liquid Anti-Xa kit is a 1-stage chromogenic assay based on a synthetic chromogenic substrate and on factor Xa inactivation. Factor Xa is neutralized directly by apixaban. Residual factor Xa is quantified with a synthetic chromogenic substrate. The paranitroaniline released is monitored kinetically at 405 nm and is inversely proportional to the apixaban in the sample.(Package insert: HemosiL Liquid Anti-Xa kit. Instrumentation Laboratory Company; Rev. 06/2017)
Day(s) Performed
24/7
Expected TAT
Same day
Performing Laboratory
Bronson Laboratory, Coagulation - Kalamazoo and Battle Creek
Sample Retention Time
24 hours
CPT Code
80299