Blood 11 Flashcards
What are the 3 clinical anticoagulants?
- Calcium Chelators
- Heparin
- Antagonists of vitamin K
Where do Calcium Chelators work?
In vitro
Where does Heparin work?
In vivo and in vitro
Where do antagonists of Vitamin K work?
In vivo
How do Calcium Chelators work?
They remove Ca2+ from the blood
How does Heparin work?
It increases the effect of Antithrombin 3
How do Antagonists of Vitamin K work?
They inhibit synthesis of factor II, VII, IX, and X in the liver
What is an an example of a Calcium Chelator?
Sodium citrate
Why aren’t calcium chelators used in vivo?
Because they would disrupt multiple systems
What is Fibrinolysis?
Breaking down a blood clot after we no longer need it
What is the solubility of Fibrin?
Insoluble
What it the inactive form of Plasmin known as?
Plasminogen
What converts Plasminogen to Plasmin?
Plasminogen activators
What are the two types of plasminogen activators?
Natural and Clinical plasminogen activators
What is the natural Plasminogen activator?
tPA
What is tPA?
The natural plasminogen activator
Where is tPA usually found?
In normal endothelium where a clot is not needed
What does tPA produce and what does it do?
Tissue Plasminogen Activator (tPA) which converts inactive plasminogen to the active plasma which breaks down fibrin
How can the release of tPA be increased?
Through exercise
What are Thrombolytic drugs?
Clinical clot busters
What is an example of a Clinical Clot Buster?
Tenectaplase
What does tenecteplase do?
It converts the inactive plasminogen to plasmin which breaks down a clot
What causes excessive bleeding or hemorrhaging?
The failure of hemostatic mechanisms to work when they are required
What does Thrombosis cause?
Formation of blood clots when they are not required; may lead to a heart attack, stroke, etc
What is the lack of enough platelets known as?
Thrombocytopenia
What can abnormal platelet function be due to?
Deficient vWF
What can cause problems with clotting factors?
Hereditary deficiencies (hemophilias) or acquired deficiencies (ie vitamin K deficiency)
