Week 5 - Deep Vein Thrombosis and Pulmonary Thromboembolism Flashcards
What is the main reason for venous thrombosis?
stasis and high risk of coagulability
What is a red vs white thrombus?
red is found in the venous system, and mostly RBC’s and fibrin.
white is found mostly in arterial system, and made of platalets and fibrin.
What is an arterial thrombus most commonly caused by?
rupture of atherosclerotic plaque causing thrombus
What is the main fates of arterial and venous thrombus?
arterial - ACS, ischaemic stroke and claudification of limbs
venous - DVT and pulmonary embolism
How does DVT occur?
in deep venous system. valves become incompetent so stasis in vessels, leading to thrombus formation.
May be caused by infection by IV use, causing thrombus
What are our main concerns regarding DVT?
pain, embolise to lungs, prevent outflow from heart
What are signs and symptoms of an embolism?
unilateral oedema, prominent superficial veins (not varicose), calf tender, knawing pain, warm, red
How do you diagnose embolism?
assess patient and history. then use pre-test probability scores.
What pre-test probability scores are available for embolism?
- DVT wells score. If low risk, do d-dimer test.
- if high risk on wells score OR positive d-dimer test, do compression ultrasound
How does a DVT wells score work?
9 factors contribute. if1 or less, low risk. if 2 or above, high risk of DVT. do compression ultrasound.
What is the “gold standard” test for DVT?
compression ultrasound test
What are positives and negatives of D dimer test?
shows breakdown of fibrin following fibrinolysis. its very sensitive for venous thromboembolism, but not specific.
positive result may be caused by trauma, malignancy, sepsis, bleeding, cancer etc
What are symptoms of pulmonary thromboembolism?
pleuritic chest pain, breathless, tachycardia, blood in sputum,
What are signs of pulmonary thromboembolism?
dyspnoea, tachycardia, shock, collapse, low BP, sudden death
What do we use to diagnose pulmonary thromboembolism?
same as pulmonary DVT.
wells score, d dimer if negative.
if indicated, imaging with isotope v/q scan and CT pulmonary angiogram