Veripath Test Directory

Synonyms Platelet Aggregation
Description Platelet Aggregation, whole blood, is the test used to assess platelet fucntion in a patient with bleeding diathesis. This assay is mimicking platelet aggregation at the site of injury to the blood vessel wall, contributing to the initial step of thrombous formation. Platelet aggregation as well as ATP secretion are studied in vitro for detection and diagnosis of acquired or congenital qualitative platelet defects. The platelets' ablility (or inability) to respond to particular aggregation agonists is the basis for differentiating platelet dysfunction. The study assesses ability of platelets to aggregate in whole blood using various concentrations of agonists such as ADP, Arachidonic Acid, Collagen, Ristocetin, as well as ability to secrete ATP in response to stimulation by thrombin, arachidonic acid and collagen.
Specimen Requirements 
Container 4 light blue (3.2% sodium citrate) and 1 purple (EDTA) collection tubes
Specimen Type Blood
Preferred Collection Volume 3mL x6 sodium citrate and 4mL EDTA
Minimum Collection Volume 3 mL x5 sodium citrate and 2mL EDTA
Collection Instructions When drawing specimens for coagulation testing, always draw a "pilot" tube (7-10ml plain red top tube), completely filled. This removes tissue fluid contamination. Samples should be obtained from peripheral vein whenever possible. If drawn from indwelling catheter, the line should be flushed with 15mL of saline. After irrigation, a "pilot" tube should be drawn and discarded.
Specimen Handling In-house patients, transport speciemen by hand at room temperature. Specimen must not be transported by automatic tube station.
Outside clients, follow collection instructions and the steps below:
1. Specimen must remain at room temperature.
2. Specimen must arrive within 1 hour after collection.
Rejection Criteria Hemolysis, contamination with heparin, clotted, short sample, >4 hrs old, frozen or centrifuged specimen
Methodology Whole Blood Aggregometry.
Reference Range See interpretive report.
CPT Code(s) 85576 X 12, 85396
Department Hemostasis/Coagulation
Contact Information Hemostasis Lab; 214-633-4959 Customer Service: 214-633-0400, Toll Free 1-877-887-8136.
Turn Around Time1-3 days
Performed Monday and Wednesday; must be scheduled with laboratory.
Performed by Hemostasis
Notes 1. Platelet count must be greater than 100,000.
2. Specimen must be accompanied by a "Platelet Aggregation Study History Form". The aggregation report will be delayed until form has been submitted.
Updated/Reviewed 07/25/2016