Platelet Function

Primary HemostasisTHE term primary or "spontaneous" hemostasis refers to a complex series of biologic events occurring in immediate response to blood-vessel severance or injury. Although damaged or cut blood vessels are known to contract, this contraction alone is insufficient to arrest hemorrhage.1 , 2 Within seconds, however, platelets are observed to adhere to the area of trauma. More platelets soon begin to arrive from the general circulation and stick to those initially deposited. The lumen of the vessel becomes progressively occluded by a platelet mass known as a hemostatic platelet plug. At first the plug is slightly permeable, and small amounts . . .