Procedure

Technical Report

Overview

The number and function of thrombocytes play a crucial part in haemostasis, that is the closure of damaged blood vessels. In addition, thrombocytes are important components in the pathogenesis of arterial thrombosis. Because of the epidemiological significance of vascular occlusion, thrombocyte function inhibitors are among the most commonly used drugs. Thrombocyte function diagnostics aims to measure reduced, normal or increased thrombocyte function. Key objectives include: - demonstration or exclusion of thrombocyte dysfunction in the form of bleeding diathesis or increased aggregation; - demonstration or exclusion of disease-induces or drug-induced thrombocyte dysfunction, specifically in the case of liver, kidney and bone marrow diseases. Examples of substances or drugs showing thrombocyte inhibition as a side effect include non-steroidal anti-inflammatory drugs, certain psychotropic medications, antihypertensives, antibiotics and a variety of dietary supplements; - monitoring the correct activity of thrombocyte function inhibitors; - functional assessment of VWF as an essential component of primary haemostasis. The following methods of assessing thrombocyte function are described in this document: - light transmission aggregometry in accordance with Born (LTA); - impedance aggregometry in accordance with Cardinal; - multiple electrode aggregometry (MEA); - PFA systems (PFA-100, PFA-200). There is a lack of standardization among the different methods used to assess thrombocyte function. Applied results, references ranges or therapeutic ranges should have been determined using essentially the same pre-analytical and analytical methods. In particular, findings (study data, clinical experience, recommendations from working groups, guidelines) that were obtained using a common measurement principle shall not be transferred between different types of instrument without prior testing. Established reagent-instrument combinations should be used for the analysis. This Technical Report has been prepared by NA 063-03-05 AA "Hämostaseologie" ("Haemostaseology") of the Medical Standards Committee (NAMed) at DIN, the German Institute for Standardization e. V.

Responsible national committee

NA 176-08-04 AA - Haemostaseology