Embolism Flashcards
What is it?
Blockage of the pulmonary artery by means of a thrombus which interrupts blood flow and supply of nutrients and 02
Causes?
Virchow’s triad
Investigations
CT pulmonary angiogram
V/Q scan
D-dimer test: measures fibrin breakdown products- will increase when clots are present
Symptoms
symptomatic -Chest pain -SOB -fatigue If in pulmonary saddle -Can lead to immediate death
If many develop over time:
- hypertension
- RV failure
Treatment
small clots break down by themselves
- Thrombolytic enzymes
- Thromnbolectomy
Preventative:
- anticoagulants e.g. heparin and warfarin
- IVC filter to prevent DVT
- compression stockings
- calf exercises
how do clots form and move into circulation?
How do clots form: Platelet cascade: -damage to endothelium -vasoconstriction -limits blood flow -platelets adhere to wall- platelet plug -clotting factors spilt- coagulation cascade:prothrombin into thrombin and fibrinogen to fibrin -fibrin forms mesh around clot- hardens it -clot can break move to RA -sometimes clot can move from RA to LA- ARTIAL SEPTUM DEFECT -from RA to pulmonary circulation -from LA to systemic circulation
Systemic/arterial emboli
causes: mural thrombus, aortic aneurysm, atheromatous plaque
Where does it travel: lower limbs, the brain
Venous/ pulmonary emboli
Causes: DVT
Where does it travel: pulmonary artery circulation- if it reaches the aortic saddle it can lead to immediate death
Risk factors: cardiac failure, severe trauma, bed rest, oral contraceptive, prophylaxis for surgical patients e.g heparin
Fat emboli
After trauma
Tends to affect the brain, kidneys and skin
air emboli
risk factors:
Head and Neck wounds
Surgery
CV lines
Other types of emboli
- trophoblast
- decompression sickens: N2 bubbles
- tumour
- bone marrow
- sepsis
- foreign materials
