The Traditional Role of Platelets in Hemostasis

Abstract

Hemostatic balance is central to health maintenance. Hemostasis must be initiated rapidly to prevent excessive blood loss. However, it must be tightly controlled to prevent over exuberant thrombus formation with resultant pathologic occlusion of arterial or venous vascular beds. Platelets are central to this hemostatic balance via primary hemostasis, support of coagulation, and even anti-fibrinolytic effects. Quantitative and qualitative platelet disorders have classi‐ cally focused on hemorrhagic and thrombotic diseases, the severity of which can range from mild to life-threatening. Recent advances have demonstrated that platelets have functions beyond their traditional hemostatic role such as supporting vascular integrity, angiogenesis, immune function, tumor metastases, etc. These “non-traditional” functions of platelet will be discussed in other chapters. In this chapter we present a brief review of the traditional roles of platelets in hemostasis and thrombosis.