Flashcards in Thrombosis Parsa Deck (22):
What are the components that contribute to thrombosis?
What causes subendothelial collagen to be exposed?
Endothelial Injury (intact cells protect against thrombosis/ coagulation etc)
Endothelial injury due to hypercholesterolemia or inflammation results in
1. Subendothelial collagen exposure
2. Adhesion and Aggregation of platelets to form platelet plug
What are the clinical and labratory assessment for assessment for endthelial injury?
1. Inflammation- C proteins
2. Infection- sepsis
3. Massive tissue destruction- obstetrical complications, CA, trauma, burns
What is the von Willebrand factor?
located on collagen for receptors of platelets for adhesion
Name of the platelet receptor?
How is aggregation accomplished?
Through the fibrinogen GpIIb-IIIa receptors on different platelets
Clinical assessment of platelets
spontaneous mucosal bleeding
petechaie and eccymoses
Laboratory assessment of platelets
platelet function studies
Types of hypercoagulation
Initial test for coagulation?
Pt and Ptt
Other main test for hypercoagulation if PT/PTT are abnormal
Secondary Causes of hypercoagulaion?
Tissue injury (e.g. trauma, surgery, burn)
Antiphospholipid antibody syndrome
Others: SCA,smoking, contraceptives, etc.
Primary causes of hypercoagulation
Point mutation in Factor V (Factor V Leiden)
In ~60% of patients with repeated DVTs
G20210A mutation → ↑prothrombin levels
Other less common and rare conditions:
↑VIII, IX, IX, or fibrinogen (unknown genetics)
↓antithrombin III, C, S, or fibrinolysis
Homozygous homocysteinuria (enzyme def)
Due to linkage with fibrinogen
Anti-phospholipid antibody syndrome (autoimmune)
How does aspirin reduce thrombosis?
by blocking TxA2 synthesis (lives the life of platelets/ 7 days)
How does warfarin stop thrombosis
antagonizes vitamin K
Too much warfarin= too much bleeding (give pt. vitamn K or clotting factors)
What is heparin's role in preventing thrombosis?
It works with antithrombonin III and prevents thrombosis 1000 times
Downside of heparin?
It can cause antbodies to come and signal IgG to produce an auto immune response leading to aggragation of platelets and cause coagulation of endothelium which can lead to thrombosis
What is a complication of heparin therapy?
Which substances promtote formation of plasmin that breaks down the fibrin and dissolves the blood clot or thrombus.
streptokinase and urokinase
Fragmented blood cells trying to get by called?
schistocytes (helmet cells)