DVT & Pulmonary Embolism Flashcards
What is a thrombus?
- blood Clotting in the wrong place
- haemostasis
What are the components of a thrombus?
3
- fibrin (end product of clotting cascade)
- platelets
- RBCs
What factors make up Virchow’s Triad?
3
- stasis
- endothelial damage
- hypercoagubility
What is meant by the stasis of blood?
- pooling of blood
- when blood flow is reduces (haemostasis) - it becomes stagnant and thrombosis sets in
What is meant by endothelial damage?
- it can mean several things
- complex atheroma plaques can rupture which leads to platelet aggregation (hypercoagubility) where thrombosis sets in.
- a complication to this could be a thromboembolism which could lead to PE (in venous thrombosis)
What is the difference between arterial and venous thrombosis, in terms of mechanism of action?
Arterial: atheroma/plaque rupture (platelet aggregation)
Venous: haemostasis/hypercoagubility
What is the difference between arterial and venous thrombosis, in terms of location of origin?
Arterial: arteries (esp. at bifurcations), coronary arteries, left heart chambers, carotid arteries
Venous: veins, venous valves, sinusoids
What is the difference between arterial and venous thrombosis, in terms of what they result in (not specifically the disease)?
Arterial: ischaemia/infarction
Venous: back pressure
What is the difference between arterial and venous thrombosis, in terms of diseases caused?
Arterial: ACS, MI, stroke, HF
Venous: DVT, PE
What is the difference between arterial and venous thrombosis, in terms of their composition?
Arterial: cream (platelets and fibrin)
Venous: red (RBCs and fibrin)
Give examples of causes of endothelial dysfunction (not damage).
(3)
- hypertension
- smoking (increased platelet aggregation)
- hyperlipidaemia (atheroma)
Give examples of causes of endothelial damage.
3
- catheters (thrombosis around catheter)
- trauma
- surgery
Give examples of causes of hypercoagubility.
3
- pregnancy (increased oestrogen, sticky platelets)
- cancer (e.g. adenocarcinoma)
- sepsis
What is an embolism?
Give examples.
Intravascular material that migrates from its original location to a distal vessel
E.g: blood clot, fat, air, tumour
Who is at higher risk of venous thromboembolism at a young age?
Why?
females - female sex hormones make their platelets more sticky.
What are some risk factors to VTE?
5
- surgery (e.g. C-section)
- varicose veins
- hypertension
- oral contraceptive
- obesity