Week 5 - Deep Vein Thrombosis and Pulmonary Thromboembolism

Question 1

What is the main reason for venous thrombosis?

Answer 1

stasis and high risk of coagulability

Question 2

What is a red vs white thrombus?

Answer 2

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.

Question 3

What is an arterial thrombus most commonly caused by?

Answer 3

rupture of atherosclerotic plaque causing thrombus

Question 4

What is the main fates of arterial and venous thrombus?

Answer 4

arterial - ACS, ischaemic stroke and claudification of limbs
venous - DVT and pulmonary embolism

Question 5

How does DVT occur?

Answer 5

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

Question 6

What are our main concerns regarding DVT?

Answer 6

pain, embolise to lungs, prevent outflow from heart

Question 7

What are signs and symptoms of an embolism?

Answer 7

unilateral oedema, prominent superficial veins (not varicose), calf tender, knawing pain, warm, red

Question 8

How do you diagnose embolism?

Answer 8

assess patient and history. then use pre-test probability scores.

Question 9

What pre-test probability scores are available for embolism?

Answer 9

• DVT wells score. If low risk, do d-dimer test.
• if high risk on wells score OR positive d-dimer test, do compression ultrasound

Question 10

How does a DVT wells score work?

Answer 10

9 factors contribute. if1 or less, low risk. if 2 or above, high risk of DVT. do compression ultrasound.

Question 11

What is the “gold standard” test for DVT?

Answer 11

compression ultrasound test

Question 12

What are positives and negatives of D dimer test?

Answer 12

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

Question 13

What are symptoms of pulmonary thromboembolism?

Answer 13

pleuritic chest pain, breathless, tachycardia, blood in sputum,

Question 14

What are signs of pulmonary thromboembolism?

Answer 14

dyspnoea, tachycardia, shock, collapse, low BP, sudden death

Question 15

What do we use to diagnose pulmonary thromboembolism?

Answer 15

same as pulmonary DVT.
wells score, d dimer if negative.
if indicated, imaging with isotope v/q scan and CT pulmonary angiogram

Question 16

What is the wells score result for high risk and low risk of PE?

Answer 16

low risk if 4 or less. high risk is 4.5 or above.

Question 17

How do you treat pulmonary thromboemblism?

Answer 17

anticoagulation for months or even life long.

Question 18

What different anticoagulant options are there for PE treatment?

Answer 18

parenteral - IV dalteparin (low molecular weight heparin) or IV unfractionated heparin in renal failure patients
enteral - direct oral anticoagulants - rivaroxaban or dabigataran. warfarin.

Question 19

What is the first line of treatment in PE?

Answer 19

first parenteral anticoagulant, then warfarin or direct oral anticoagulant

Question 20

What are potential long term consequences of DVT?

Answer 20

post thrombotic syndrome - damage to venous valves. swelling, discomfort, ulceration. 20-60% incidence in 2 years

Question 21

What are potential long term consequences of PE?

Answer 21

most recover fully. may lead to hypertension. treated by removing blood clot