Topic 3: Thrombosis, Embolism, Infarction Flashcards
What is the definition of a thrombus?
What is the difference between a thrombus and a blood clot?
What is the normal response to haemorrhage? (3 steps)
Compare haemostasis and thrombosis?
What 4 factors inhibit thrombosis?
- intact endothelial cells
- anticoagulant molecules and platelet inhibition
- fibrinolysis
- lamina flow
What is Virchow’s triad?
- factors that predispose you to thrombosis
What causes changes in the vessel wall?
- injury to or activation of endothelium or exposure of subendothelial layers (collagen)
- atherosclerosis *
- inflammation
- trauma (tumour)
Describe normal blood flow
- laminar
- keeps platelets away from endothelium
What causes stasis and turbulent flow (change in blood flow)?
- disruption of laminar flow
- endothelial activation
- stasis is a major contributor to venous thrombi ( AKA clots)
- veins
- aneurysm, when you get an out pouch of a vessel, lose elasticity
What are changes in the constituents of blood?
- hereditary (factor 5 mutations, deficiency of anticoagulant molecules)
- acquired - more common (increase in coagulation factors, hyperviscosity- reduces flow)
what are 2 types of thrombi?
- venous
- arterial
What are the risk factors for developing DVT (deep vein thrombosis)?
- immobilisation
- post-surgical
- cancer
- pregnancy
- heart failure
- dehydration
What is trousseau syndrome?
when cancer causes venous thrombosis
What are the macroscopic signs of DVT?
- attachment to valves
- -
What are the microscopic signs of DVT?
- full of red cells, darker area
- lighter area, fibrin
- irregular laminations
- granulation tissue
- attempted recanalisation (round empty spaces)
What are some outcomes of DVT?
- resolution
- granulation repair (origination)
- recanalisation
- goes into lungs, embolisation
What are some DVT clinical manifestations?
- swollen
- tender
- identify predisposing factors
- associated warms and redness