LTA Assessement Using Aggregometer TA-8V (Stago®)

Study Overview
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Brief Summary
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Exploring platelet functions requires aggregation tests platelet. The Haematology Laboratory of Hospices Civils de Lyon currently has two new TA-8V plate aggregation automatons® (Stago). The supplier of these devices does not offer reference values for these tests. There are also no references in the data literature. Therefore reference values must be established from healthy volunteer subjects. The use of these automatons is subject to the NF (French Standard) EN (European Standard) ISO (International Organization for Standardization) 15189 standard of the COFRAC ( French Accreditation Comity) that requires checking their proper functioning. This audit must be traced in a method validation folder.

Official Title
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Normal Values and Quality Assessment of Light Transmission Aggregometry (LTA) Using Aggregometer TA-8V (Stago®)

Conditions
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Healthy Volunteer

Intervention / Treatment
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* Device: Take blood (TA-8V (Stago®)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female adults aged between 18 and 70 years Weighting more than 50 kg Subjects having signed informed consent Subjects registered in the French health-care system database Exclusion Criteria: Personal history of anemia, thrombopenia, hemorrhagic disease Caffeine intake 2 hours prior to blood sampling Tobacco intake in the half hour prior to blood sampling Use of any drug impacting platelet function for antiplatelet agents: at least 10 days prior to blood sampling for anti-depressants: at least 10 days prior to blood sampling for non-steroid anti-inflammatories: at least 3 days prior to blood sampling Refusal to undergo the 3 visits and 3 blood samples of the study Refusal to sign the informed consent form No registration in the French Health-care system database Pregnant women and women who are breastfeeding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: 30 healthy adult volunteers<br>Healthy adult volunteers without hemorrhagic diathesis. | Device: Take blood (TA-8V (Stago®)<br>* Healthy volunteers will have 3 blood samples at M0, M3 and M6.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Platelets aggregation results for LTA on TA-8V (Stago®) | Normal values for platelets aggregation will be established using various agonists to activate platelets. : • Ristocetin (STAGO®) | Month 0 | 
| Platelets aggregation results for LTA on TA-8V (Stago®) | Normal values for platelets aggregation will be established using various agonists to activate platelets. : Collagen (STAGO®) ADP (adenosine diphosphate) (STAGO®) Arachidonate (STAGO®) TRAP (Thrombin Receptor Activating Platelet) (STAGO®) | Month 3 | 
| Platelets aggregation results for LTA on TA-8V (Stago®) | Normal values for platelets aggregation will be established using various agonists to activate platelets. : Epinephrine (STAGO®) PMA (phorbol 12-myristate 13 acetate) (SIGMA®) PAF (Platelet Activator Factor) (BACHEM®) Ionophore calcium (SIGMA®) 11-Epoxy (SIGMA®) Prostaglandin E1 (SIGMA®) | Month 6 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| LTA intra assay variability | Intra assay variability of maximal platelet aggregation will be assessed by calculating a coefficient of variation of the studied parameters. | Month 0 | 
| LTA intra assay variability | Intra assay variability of maximal platelet aggregation will be assessed by calculating a coefficient of variation of the studied parameters. | Month 3 | 
| LTA intra assay variability | Intra assay variability of maximal platelet aggregation will be assessed by calculating a coefficient of variation of the studied parameters. | Month 6 | 
| LTA inter operator variability | Inter operator variability of maximal platelet aggregation will be assessed by percentage of agreement (%). | Month 0 | 
| LTA inter operator variability | Inter operator variability of maximal platelet aggregation will be assessed by percentage of agreement (%). | Month 3 | 
| LTA inter operator variability | Inter operator variability of maximal platelet aggregation will be assessed by percentage of agreement (%). | Month 6 | 
| Agonist reagents stability duration | Reagents will be reconstituted and stored at -20°C. They will be used for aggregation assay extemporaneously, 1 week, 2 weeks , 1 month and 2 months post reconstitution. | up to 2 months post reagents reconstitution and 2 months post reconstitution with the same technician, the same automaton and the same healthy volunteer sample. | 
| Agonist reagents stability duration | Reagents will be reconstituted and stored at -20°C. They will be used for aggregation assay extemporaneously, 1 week, 2 weeks , 1 month and 2 months post reconstitution. | up to 2 months post reagents reconstitution | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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light transmission aggregometry, platelets, platelet functions, von Willebrand disease, quality assessment