Introduction to Hemostasis Flashcards
What is hemostasis?
Hemostasis is a critical physiological process that involves a series of rapid, defensive reactions aimed at stopping excessive bleeding and promoting healing after a vascular injury.
What are the main phases of hemostasis?
The main phases are the vascular phase and the platelet phase.
What triggers the vascular phase of hemostasis?
Injury or trauma triggers the vascular phase, leading to rapid constriction of blood vessels.
Describe the role of platelets in hemostasis.
Platelets adhere to the site of injury, aggregate to form a plug, and release clotting factors that facilitate coagulation.
What is platelet aggregation and why is it important?
Platelet aggregation is the process where activated platelets stick together to form a loose plug at the injury site, crucial for stopping bleeding.
How do platelets contribute to the coagulation phase?
Platelets release clotting factors that are essential for the final coagulation process, leading to the formation of a stable blood clot.
Example of hemostasis in action?
When a blood vessel is cut, the immediate response is vasoconstriction to minimize blood loss. Platelets quickly adhere to the exposed collagen and become activated, releasing substances that recruit additional platelets. This forms a platelet plug, which is then reinforced by the coagulation cascade initiated by the clotting factors released by the platelets.
