Thrombus/Embolism Flashcards
What are the three branches of Virchow’s Triad?
Endothelial injury, hypercoaguability, abnormal blood flow
What could cause hypercoaguability of blood?
Post-partum, smoking, sickle cell anaemia, genetic disorders (eg protein C and S deficiency, anti-thrombin III deficiency), MI, AF
What abnormalities in blood flow could lead to a thrombus?
Stasis, turbulent flow, decreased dilution of clotting factors
How could endothelial injury lead to thrombus formation?
Could form an atheroma, inflammation, loss of endothelium therefore exposed matrix, platelet adhesion, tissue factor release
What are the possible effects of an arterial thrombus?
Ischaemia and infarction (severity depends on site and collateral supply)
What are the possible effects of a venous thrombus?
Pulmonary embolism, oedema, venous congestion, ischaemia, infarction
How do venous and arterial thrombi differ in appearance?
Venous are darker, more red, with higher cell content, softer and gelatinous. Whereas arterial are paler, lines of Zahn, their first layer is always platelets then alternate layers of fibrin.
What is respiratory compromise?
Where there is a mismatch in perfusion:ventilation resulting in hypoxaemia
What is haemodynamic compromise as a result of a pulmonary embolism?
The pulmonary embolism increases resistance to pulmonary blood flow, this then increases pressure in right heart leading to acute right sided heart failure.
How does warfarin work? What is it used for?
Prevention of thrombosis. Works by inhibiting vitamin K (vit K antagonist)
How does heparin work? And what is it used for?
Prevent DVT, blood thinner, unstable angina. Binds to and activates anti-thrombin III. Anti-thrombin III lyses thrombin (factor II) and factor X, TF prevents thrombus formation.
