Coagulation Flashcards
What does thrombin do
-Activate platelets
-Convert fibrinogen to fibrin
-Sustainment of coagulation by activating V, VIII, XI
-Activation of XIII leading to clot stability
What is the initiation of coagulation cascade
Extrinsic through VII, III, Ca, and platelets surface
Intrinsic pathway
Amplifies the coagulation pathway until it reaches the common pathway
Why do we need Ca in the coagulation cascade
Needed to bind the factor to platelet surface because they are negatively charged
Tissue Factor complex
TF, VIIa, X/IX(gets activated)
Tenase complex
VIIIa, IXa, X(gets activated)
Prothrombinase complex
V, X, II(gets activated)
Will you see coagulation disorders from hypocalcemia
No, if levels got that low it would be dead from other issues
What factor has the shortest half life
VII 4-6hrs
What is key to fibrinolysis
Plasmin
How is plasmin made
Endothelial cells synthesize tPA and urokinase which converts plasminogen to plasmin that can then break down fibrin
What happens if there is free plasmin in the blood
It is bound by antiplasmin to prevent fibrinolysis of other clots
Anticoagulant effects
Thrombomodulin
Antithrombin
Protein C and S
Heparin like molecules
Tissue factor pathway inhibitor
What are the Vitamin K dependent Factors and proteins
II, VII, IX, and X
Why is vitamin K important
Reduced vitamin K activates coagulation proteins and allows them to receive an overall negative charge to interact with Ca
