Coagulation Flashcards
1
Q
How does coumadin work?
What factors are affected?
What lab is increased?
A
- causes synthesis of non functional factor VII and inhibits the extrinsic pathway
- Factors II (prothrombin), IX, and X are also affected
- increases PT
- does nothing to CURRENT clotting factors, but affects FUTURE clotting factors
2
Q
How does heparin work?
What factors are affected?
What lab is increased?
A
- increases inactivation of thrombin (IIa), which inhibits activation of factor VIII and inhibits the intrinsic pathway
- works to stop a CURRENT clot
- increaes PTT
- activated antithrombin III, which breaks down factors Xa and IIa
- naturally occurring, produced by basophils and mast cells
3
Q
How is the intrinsic pathway activated?
A
- by contact with the basement membrane
4
Q
How is the extrinsic pathway activated?
A
- by tissue factor which is presented on subendothelial cells
5
Q
What happens in common pathway?
A
- results in activation of prothrombin to thrombin which converts fibrinogen to fibrin
- cross linked fibrin holds platelets & RBCs together to form a clot
6
Q
What are the 4 nonimmune platelet destruction disorders?
A
- thrombotic thrombocytopenia purpura
- hemolytic uremic syndrome (HUS)
- HELLP syndrome
- disseminated intravascular coagulation (DIC)
7
Q
What are 3 immune platelet destruction disorders?
A
- post transfusion purpura
- heparin induced thrombocytopenia
- idiopathic thrombocytopenia purpura
8
Q
venous hypercoagulability
A
- slow moving blood with excess thrombin formation
9
Q
arterial hypercoagulability
A
- fast moving blood with excess plt function
