Specimen Requirements

Involves special collection requirements.  Kits for drawing this test have been supplied to units that will be ordering the test.  The kits include 2.0 mL Greiner Bio-One partial fill vacuete tubes with 3.2% sodium citrate (blue-top), a discard tube, a 21 gauge needle and instructions for collection.

Draw 2 Greiner blue-top tubes using a 21 gauge needle to the black line on the tube (1/2 tube).  Do not under fill.

Invert gently 5 times to mix blood.

Specimens cannot be sent throught the pneumatic tube system.  They must be hand delivered to the lab. 

Testing must be completed within 4 hours of collection.

Notes:  Limitations of the test include interference by other antiplatelet drugs such as Glycoprotein IIb/IIIa inhibitors.   Patients who have been treated with Glycoprotein IIb/IIIa drugs should not be tested until platelet function has recovered.  this time period is approximately 14 days after discontinuation of drug administration for abciximab (ReoPro) and up to 48 hours for eptifibatide (Integrilin) and tirofiban (Aggrastate).  The platelet function recovery time varies among individuals and is longer for patients with renal dysfunction.  Dilostazol may affect test results; the average duratio of the platelet inhibitory effec is 12 hours.   Patients with inherited platelet disorders such as von Willebrand Factor Deficiency, Glanzmann Thrombasthenia and Bernard-Soulier syndrome have not been studied with the VerifyNow PRUTest.  The VerifyNow PRUTest is not intended for use with these types of platelet disorders.  Aspirin and NSAIDs show no significant inhibition of the PRU value.  The effect to platelet counts less than 100,000 X 10⁹ /L, platelet counts greater than 502,000 X 10⁹ /L, fibrinogen less than 171 mg/dL, fibrinogen greater than 599 mg/dL, hematocrits less tha 33%, and hematocrits greater than 52% have not been studied.