12. thrombosis and embolism Flashcards
thrombosis etiology
virchows triad
hypercoagulability
stasis
endothelial injury
endothelial injury
hypertension,
turbulent blood flow,
bacterial endotoxins,
radiation injury,
hypercholesterolemia,
homocysteineamia
Abnormal blood flow
turbulence
Turbulence
Commonly associated with hypertension, Ulcerated atherosclerotic plaques
Arterial and cardiac thrombosis
stasis
Stasis
Typically seen in hyperviscosity syndromes (PV), Aneurysms, sickle cell anemia, mitral valve stenosis (left atrial dilation) and myocardial infarctions
Venous thrombi
hypercoagubality type
genetic primary
acquired secondary
genetic primary hypercoa factors
common
factor 5 leiden - arg to gln - resistant to protein c
prothrombin mutation
increased factors
rare
deficient protein c and s
thrombi show lines of
zahn
red cells fibrin red cell fibrin
Fate of a thrombus
Propagation
Embolization
Dissolution
Organization and recanalization
Inflammation and fibrosis (central liquefaction, bacterial seeding and influx of inflammatory cells)
types of thrombi
Mural thrombi; Attached to one wall of an underlying structure (heart chambers and aorta)
Arterial thrombi; Usually occlusive in smaller vessels or mural in large vessels
Venous thrombi (= phlebothrombosis, red or stasis thrombi)
90% veins of lower extremity
always occlusive and always have a point of attachment to the underlying structure
Lines of Zahn are not well developed
Vegetative thrombi (NBTE); on heart valves
Embolus
Embolus: intravascular solid, liquid, or gaseous mass that is traveled through the circulation until becoming lodged in a small vessel
Classification based on physical state
Solid: Atheromatous, thromboemboli, tumor emboli, Fat and bone marrow
Liquid: Amniotic fluid emboli
Gaseous: Air emboli
based on site of origin
Cardiac emboli (left side of heart), Arterial emboli (atheromas and aneurysms), Venous emboli (deep vein thrombosis) and Lymphatic emboli (tumor emboli)
based on presenece of infection
Sterile/bland emboli and Septic emboli
based on flow
Paradoxical emboli/crossed emboli- artery to vein
Retrograde emboli; Increased pressure in the body cavities during coughing or straining carries emboli from large thoracic ducts and abdominal veins.
Pulmonary embolism(PE) origin common
bed ridden patients
DVT
symptoms of pulm emboli
cough,
severe pleuritic pain,
shortness of breath,
occasionally haemoptysis and haemorrhagic pleural effusion
types of pulm emboli
central
intermediate
peripheral
cental emboli
Sudden death due to right-sided heart failure or cvs collapse
Saddle embolus; Straddle the pulmonary artery bifurcation
Intermediate emboli
Occurs at branches of the pulmonary artery in the lungs
has a collateral circulation from the bronchial artery
so the area would not be necrotic
peripheral emboli
Obstruction of end-arteriolar pulmonary branches where the bronchial artery don’t reach - red (hemorrhagic) infraction
Chronic Thromboembolic Pulmonary Hypertension (CTEPH)
Multiple emboli clogging pulmonary capillary circulation
Systemic thromboembolism origin
2/3 from left ventricular wall infarcts
1/4 from left atrial dilatation and fibrillation
The remaining from aortic aneurysms, atheromas, valvular vegetations and paradoxical emboli
Fat embolism cause
Trauma to long bones or soft tissue (fracture with embolization of fatty marrow)
Extensive burns
Pancreatitis
Vigorous cardiopulmonary resuscitation
