Coagulation Disorder Drugs (M2) Flashcards
How do endothelial cells of intact blood vessels prevent blood clotting?
- Nitric oxide and protscyclin prevent platelet aggregation
- Thrombomodulin
- Heparin-like molecule
What are the three steps in hemostasis?
- vasoconstrication
- platelet plug formation
- blood coagulation (fibrin clot)
What is secreted by platelets (and what do they do)?
- thromboxane A2, TXA2 (vasoconstrictor and platelet activator)
- ADP (platelet aggregation)
- serotonin, 5-HT (aggregation and vasoconstriction
What are the roles of thrombin in the blood coagulation cascade?
- cleaves peptides from fibrinogen to form fibrin
- activates clotting factors
- activates factor XIII to stabilize clot
- activates protein C pathway, attenuates clotting
What does tissue factor (TF) bind to? 1. What does this complex activate? 2
- factor VIIa
2. factors X and IX
What factors form prothrombinase (thromboplastin)?
Xa and Va
What factors doe thrombin activate upstream?
V, VII, XI
What does Antithrombin (AT) inactivate?
IIa, IXa, XIa, XIIa
For a Factor V Leiden patient what do they have a resistance to?
Protein C an Protein S
What is fibrin digested by? 1. What activates this? 2
- plasmin
2. tPA
What is the disease in which coagulation and fibrinolytic systems are pathologically activated?
Disseminated Intravascular Coagulation (DIC)
What is administered if there is a too much Heparin in the system?
Protamine sulfate (antagonist)
Which type of Warfarin is more potent: S-warfarin or R-warfarin?
S-warfarin 4x more
What is a prothrombin time ratio? 1. What is a recommended value? 2
- International Normalized Ratio (INR)
2. 2-3
What is given to reverse Warfarin action when needed?
- oral or parenteral vit K1
- Prothrombin complex concentrates
- Recombinant factor VIIa
