Thrombosis And embolism Flashcards
What is thrombosis?
Formation of a solid mass of blood within the circulatory system.
Why is a clot considered different to a thrombosis ?
A clot is a mass of blood outside the vessel wall whereas thrombosis is a mass of blood within the blood vessel.
What does Virchow’s triad mean ?
It is an explanation of how a thrombus forms. A thrombus forms when there is an abnormality in :
- Vessel wall
- Blood flow
- Blood components
How can damage to a vessel wall lead to a thrombus?
- Direct injury could damage vessel wall.
- Inflammation of the vessel wall
- Atheroma of the vessel wall
How can problems with blood flow lead to a thrombus?
Slowing of blood ( stasis). Old lead to problems with blood flow. This can happen through sitting down for long periods of time eg on a plane.
How can problems with blood components lead to thrombus ?
Hypercoagulable states of blood lead to problems with blood. This is where the blood is sticky.
This often is the case in : trauma / burn patients because they are dehydrated.
Pregnant women
Smokers
Post Mortimer patients
Cancer patients
What patients are at a higher risk of developing hypercoagulable states of blood ?
Pregnant women
Burn patients
Smokers
Cancer patients
Post mortem patients
What are differences between arterial thrombus and venous thrombus ?
Arterial thrombus are pale , granular , lines of Zahn , lower cell content whereas in venous thrombus they are soft , gelatinous , deep red and higher cell content
What are 5 different possible outcomes of a thrombus formation ?
- Lysis
- Propagate
- Organise
- Recanalise
- Embolise
‘ lads pop oranges right everywhere’
What is lysis of a thrombus ?
This is when the thrombus disappear naturally .
This is the most likely outcome when the thrombi are small.
There is complete dissolution of the thrombus - the fibrinolytic system is active. And after blood flow is the re established.
What is propagation of a thrombus ?
Progressive spread of a thrombosis.
This occurs distally in arteries - thrombus spreads away from the heart.
Whereas in veins the thrombus propagates proximally.
What is organisation of a thrombus ?
- the thrombus doesn’t dissolve natural.y. Instead a reparative process occurs where there is an in growth of fibroblasts and capillaries which forms something similar to granulation tissue.
- so the lumen remains obstructed
What is rencalisation of a thrombus ?
- this is where holes form in the thrombus - so blood flow is reestablished but usually incompletely due to one or more channels formed through the thrombus
What occurs when a thrombus embolise ?
This is where part of the thrombus breaks off. And these parts travel through the blood stream and lodge at different sites.
What are the effects of thrombosis in tissue in a venous vessel ?
- Congestion
- Oedema
- Ishcameia
- Infaraction
