Test Code VerifyNow PRUTest Clopidogrel Response Test with VerifyNow
Aliases
Clopidogrel Response Test, P2Y12
Useful For
The VerifyNow PRUTest is designed to measure platelet P2Y12 receptor blockade. Substances known to specifically block the p2Y12 receptor include clopidogrel, prasugrel and ticagrelor
Patient Preparation
Typically ordered for patients of Neurosurgery.
Special Collection Instructions
A Greiner NaCitrate tube must be used.
Collection Method
Whole blood samples must be collected in a Greiner 2.0 mL blue top, NaCitrate tube containing 3.2% Sodium Citrate. Please note that citrate BD Vacutainers are not acceptable. The tube must be filled to its intended whole blood capacity (indicated by small black line). Please call the Coagulation Lab for the correct collection tube.
Minimum Volume
Tubes properly filled to the indicator line on the tube.
Container
Greiner 2.0 mL blue top
Preferred Specimen
Only Greiner NaCitrate tubes are acceptable.
Acceptable Specimens
Only Greiner NaCitrate tubes are acceptable.
Reference or Target Ranges
182 – 335 PRU
Applies to patients prior to the treatment with platelet
inhibitors
Reportable Units
PRU (P2Y12 Reaction Units)
Critical Value
Not defined for this assay
Reasons for Rejection
Hemolysis Threshold | N/A |
Icterus Threshold | N/A |
Lipemia Threshold | N/A |
Interfering Subtances/Other | Hemolysis, mishandled, mislabeled, clotted, short draws,
overdraws, wrong tube type (Griener NaCitrate is the only
acceptable tube) Note: Samples that are short draws, over draws, or clotted will yield incorrect results. Tubes transported through pneumatic tube system, refrigerated, centrifuged, or clotted specimens are not acceptable and must be redrawn. |
Specimen Stability
Ambient | Up to 4 hours |
Refrigerated (4°C to 8°C) | N/A |
Frozen(-70°C to -20°C) | N/A |
Performance Information
Days and Time Performed | 24/7 |
Expected Turn Around Time | Stat: 1 hour on arrival to lab Routine: 4 hours on arrival to lab |
Stat Availability | Yes |
Performing Bench | UH Coagulation |
Methodology/Method Description | VerifyNow – The VerifyNow PRUTest reports results in P2Y12 reaction units (PRU), which report the amount of P2Y12 receptor mediated aggregation specific to the platelet, and are calculated as a function of the rate and extent of platelet aggregation in the ADP channel. |
Special Handling
Walk to Laboratory - do not send through tube
system.
Deliver Immediately - test must be performed
within 4 hours of collection.
Special Delivery Instructions - Samples must be
hand delivered to 2nd floor Lab Blood Bank/Coagulation
department, room L2000.
Additional Information/Important Notes
Other anti-platelet agents such as cilostazol or GPIIb/IIIa
inhibitors will be associated with decreased results as well.
Patients who have been administered tirofiban
(Aggrastat®) or eptifibatide
(Integrilin®) within two days, or abciximab
(ReoPro®) within two weeks should not be tested.
Invalid results may be obtained in patients with abnormal platelet
counts.
The VerifyNow instrument also allows the user to calculate a
percent inhibition for a given patient, provided that the baseline
PRU value was obtained prior to administration of the drug using
the following formula:
CPT Codes
85576