Picker Susanne M
Transfusion Medicine, University Hospital of Cologne, Germany.
Transfus Apher Sci. 2011 Jun;44(3):305-19. doi: 10.1016/j.transci.2011.03.006. Epub 2011 May 23.
Platelets (PLTs), play a key role in hemostasis, clot stability and retraction as well as in vascular repair and anti-microbial host defense. Upon vessel wall damage, PLTs undergo a highly regulated set including adhesion, spreading, aggregation, release reactions as well as exposure of procoagulant surfaces to rapidly form a hemostatic plug that occludes the site of damage. When PLT function is impaired, the bleeding risk increases, but (hyperreactive) PLTs are also involved in many pathophysiological events like thrombosis, vessel constriction, atherogenesis, tumor growth and metastasis, inflammation including atherosclerosis and the subsequent formation of arterial thrombi resulting in stroke and myocardial infarction. While hereditary PLT function disorders are very rare, acquired PLT function abnormalities occur in the course of many diseases and can be associated with many drugs, i.e., non-steroidal anti-inflammatorics, antibiotics or heparin. Therefore, apart from disease diagnosis, severity, and prognosis, assessment of PLT function also serves for identifying the efficacy of anti-PLT therapy and PLT hyperfunction as a possible predictor for thromboembolic events. Since PLTs undergo a lot of measurable changes during storage ex-vivo, one effort of transfusion medicine is the quality monitoring of PLT concentrates (PCs), but also the detection of donors with PLT dysfunction and the determination of patients in which PLT transfusions are effective. The majority of PLT tests focus only on PLT functions involved directly in hemostasis including adhesion/aggregation, coagulation, and clot retraction. Traditional tests, almost complex, time-consuming, and poorly specified, are meanwhile enriched by more user friendly and easy-to-use point-of-care tests on fully automated instruments within whole blood without the requirement of sample processing. These tests help identifying surgical patients at increased risk of post-operative bleeding or with resistance to anti-PLT therapy, therefore at increased risk of thromboembolism. However, up to now, no study shows real outcome benefits by including these tests into the disease management. To date, no function test is suitable to address all distinct steps of PLT activation or reliably predict PLT behavior in vivo following transfusion.
血小板（PLTs）在止血、凝块稳定性和收缩以及血管修复和抗微生物宿主防御中发挥关键作用。血管壁受损时，血小板会经历一系列高度调控的过程，包括黏附、铺展、聚集、释放反应以及促凝表面的暴露，从而迅速形成一个止血栓，堵塞受损部位。当血小板功能受损时，出血风险增加，但（反应过度的）血小板也参与许多病理生理事件，如血栓形成、血管收缩、动脉粥样硬化、肿瘤生长和转移、炎症（包括动脉粥样硬化）以及随后导致中风和心肌梗死的动脉血栓形成。虽然遗传性血小板功能障碍非常罕见，但获得性血小板功能异常在许多疾病过程中都会出现，并且可能与许多药物有关，如非甾体抗炎药、抗生素或肝素。因此，除了疾病诊断、严重程度和预后评估外，血小板功能评估还用于确定抗血小板治疗的疗效以及血小板功能亢进作为血栓栓塞事件的可能预测指标。由于血小板在体外储存期间会发生许多可测量的变化，输血医学的一项工作是对血小板浓缩物（PCs）进行质量监测，同时检测血小板功能障碍的献血者并确定血小板输注有效的患者。大多数血小板检测仅关注直接参与止血的血小板功能，包括黏附/聚集、凝血和凝块收缩。传统检测方法几乎都很复杂、耗时且特异性差，与此同时，更用户友好且易于使用的即时检验（POCT）在全血的全自动仪器上得到了丰富，无需样品处理。这些检测有助于识别术后出血风险增加或对抗血小板治疗有抵抗性的手术患者，因此这些患者血栓栓塞风险增加。然而，到目前为止，没有研究表明将这些检测纳入疾病管理能带来实际的预后益处。迄今为止，没有一种功能测试适合解决血小板激活的所有不同步骤，也无法可靠地预测输血后血小板在体内的行为。
