Venous thromboembolism (VTE)

Question 1

What is a DVT?

Answer 1

When a thrombus (blood clot) forms in the venous circulation

Question 2

Where are the most common sites of DVTs?

Answer 2

Lower leg / calves
Thigh
Pelvis

Question 3

What is a pulmonary embolism (PE)?

Answer 3

When a thrombus has embolised (traveled from its original site) to the lungs where it lodges in the pulmonary veins

Question 4

Describe the route that a DVT embolises to the lungs

Answer 4

From the deep veins –> right side of the heart –> lungs

Question 5

What are some risk factors for VTE?

Answer 5

Obesity
High cholesterol 
Immobility
Recent surgery
Long haul travel
Pregnancy
Hormone therapy with oestrogen - COCP or HRT
Malignancy
Certain blood disorders - e.g. polycythaemia, thrombophilia

Question 6

What is polycythaemia?

Answer 6

Increased number of red blood cells in the body

Question 7

What is anti-phospholipid syndrome?

Answer 7

A type of thrombophilia - When your immune system creates antibodies that bind to phospholipids -making blood more likely to clot

Question 8

What is involved in VTE prophylaxis?

Answer 8

LMWH - e.g. enoxaparin

Anti embolic compression stockings / intermitter pneumatic compression stockings

Question 9

When is giving low molecular weight heparin contraindicated for VTE prophylaxis?

Answer 9

Active bleeding
In patients already on anticoagulants - e.g. warfarin or DOACs
Straight before surgery

Question 10

What is the presentation of a DVT?

Answer 10

Unilateral calf or leg swelling
Tenderness to calf
Dilated superficial veins
Oedema
Colour changes / erythema
hot to touch

Question 11

How is the amount of leg swelling examined?

Answer 11

Measure the circumference of the calf 10cm below the tibial tuberosity and compared to the other leg. More than 3cm difference is significant.

Question 12

Name the scoring system used to predict risk of DVT / PE

Answer 12

Wells score

Question 13

How are DVTs diagnosed?

Answer 13

D dimer (sensitive but not specific - so more useful in excluding VTE)
Doppler ultrasound of the leg

Question 14

How are PEs diagnosed?

Answer 14

Clinical presentation - e.g. signs of a DVT
CT pulmonary angiogram (CTPA)
Ventilation perfusion scan (if allergic to contrast or significant renal impairment)

Question 15

What is the initial management for a DVT?

Answer 15

Anticoagulation - most commonly apixaban or rivaroxaban

Question 16

Give examples of some conditions that may raise D dimer

Answer 16

Venous thromboembolism / DVT / PE
Malignancy
Heart failure
Surgery
Pregnancy
Pneumonia
Infections

Question 17

What different types of medications can be given for long term anticoagulation in VTE?

Answer 17

DOACs - e.g. apixaban, rivaroxban

Warfarin

LMWH - low molecular weight heparin

Question 18

What is the first line anticoagulant in pregnancy?

Answer 18

Low molecular weight heparin

Question 19

What is the mechanism of action of Warfarin?

Answer 19

A vitamin K antagonist. Hence stops the production of clotting factors.