Hemostasis Flashcards
What is hemostasis?
the process of the clotting of blood and the breakdown of the clot after repair
How does the body respond to vascular injury?
vasospasm, platelets help form platelet plug, the body responds to the plug by forming fibrin mesh, followed by fibrinolysis, fibrin is then replaced by collagen
What clotting factor is most important for hemostasis?
clotting factor VIII
von Willebrand clotting factor
What are the three categories of hemostasis?
primary hemostasis, secondary hemostasis, tertiary hemostasis
What is primary hemostasis?
formation of the platelet plug
What is step one of primary hemostasis?
platelet adhesion - platelets stick to vessel walls
What is step two of primary hemostasis?
platelet activation - platelet adhesion to vessel walls causes platelets to change shape
What is step three of primary hemostasis?
platelet aggregation-formation of the primary platelet plug
If an abnormality occurs during primary hemostasis, what happens?
results in hemorrhage and prolonged bleeding
What is secondary hemostasis?
the coagulation cascade
What does secondary hemostasis result in?
formation of fibrin
What are the three pathways of secondary hemostasis?
extrinsic, intrinsic, common
What is extrinsic?
used when damage occurs outside a vessel
What is intrinsic?
used when damage occurs inside a vessel
What is the common pathway?
production of fibrin to fibrinogen
