Pathophysiology of thrombosis and embolism (part 2) Flashcards
What is an embolism?
movement of abnormal material in the bloodstream and its impaction in a vessel, blocking its lumen
What is an embolus?
detached intravascular solid, liquid or gaseous mass
What are most emboli?
are dislodged thrombi (thromboembolism)
What are types of embolus?
- thrombus:
- Fat
- Gas
- Air embolus
- tumour
- trophoblast
- septic material
- amniotic fluid
- bone marrow
- foreign bodies
What are sources of thrombus and system/arterial thromboembolus?
mural thrombus (associated with MI or left atrial dilation + AF)
aortic aneurysms
atheromatous plaques
valvular vegetations
What can venous thrombi form?
paradoxical emboli
What are the most common systemic thromboembolus sites?
lower limbs most common
also brain and other organs
What do the consequences of systemic thromboembolus depend on?
depend on vulnerability of affected tissue to ischemia
calibre of occluded vessel
collateral circulation but usually infarction occurs
Where does venous thromboembolus originate?
originate from deep venous thromboses (lower limbs)
Where can the thromboembolus travel to?
pulmonary arterial circulation
What are consequences of pulmonary thromboembolus?
depend on size of embolus:
silent pulmonary haemorrhage/infraction, right heart failure, sudden death
What are the risk factors for DVT and pulmonary thromboembolism?
cardiac failure, severe trauma/burns, post-op/post-partum, nephrotic syndrome, disseminated malignancy, oral contraceptive, increase age, bed rest/immobilisation, obesity, PMH, DVT
What prophylaxis would you give for patients at risk?
TEDS, s/c heparin
What can fat rmbolus affect?
brain (lead to confusion)
kidneys (reduction in renal function)
skin affected (rash)
What ae types of thrombombolus?
systemic/arterial thromboembolus
venous thromboembolus
