Venous Thromboembolism (Deep Vein Thrombosis)

Question 1

Define deep vein thrombosis

Answer 1

The formation of a thrombus in a deep vein, usually in the legs

Question 2

Describe the pathophysiology of DVT

Answer 2

A Deep Vein Thrombosis (DVT) is a clot formation in a deep leg vein

Question 3

What is Virchow’s triad?

Answer 3

The factors needed for thrombus formation

Question 4

What are the 3 components of Virchow’s triad?

Answer 4

• Hypercoagulability
• Venous stasis
• Endothelial damage

Question 5

What is hypercoagulability?

Answer 5

• Increased platelet adhesion and clotting
• It can be hereditary or acquired

Question 6

What is venous stasis?

Answer 6

Normally, blood flow is laminar and platelets and clotting factors aren’t activated, but in stasis, there is an aggregation of clotting factors which leads to a thrombus, caused by immobility

Question 7

What is endothelial damage?

Answer 7

Endothelial cells normally secrete anticoagulants but if they are damaged, they don’t. Trauma and surgery can lead to this

Question 8

Which veins are more commonly affected?

Answer 8

Minor veins are more commonly affected, and they are found below the calf and they’re less concerning

Question 9

What happens when major veins are affected?

Answer 9

• Major veins being affected are rarer but are life-threatening
• These are found above the calf.

Question 10

What can DVT be mistaken for?

Answer 10

It might be mistaken for cellulitis as it presents similarly, but cellulitis will show leukocytosis on FBC whilst DVT is normal

Question 11

What are symptoms of DVT?

Answer 11

• Unilateral calf pain, redness and swelling
• Phlegmasia Cerulea Dolens can occur in a massive DVT which can result in ischaemia and a blue painful leg.

Question 12

What are signs of DVT?

Answer 12

• Unilateral swelling
• Oedema
• Tender
• Erythematous
• Distension of superficial veins

Question 13

What criteria is used to diagnose DVT?

Answer 13

• A Wells score is used to determine if there is a risk of DVT and determines following investigations or management
• If it is 2 or over, a DVT is likely

Question 14

What is used to diagnose DVT?

Answer 14

Duplex Ultrasound of the leg is gold standard but if it is unavailable a D Dimer test can be carried out

Question 15

What treatments can be used for DVT?

Answer 15

• Direct Oral Anti-Coagulants: Apixaban or Rivaroxaban
• If there is a contraindication, you can give LMWH or Unfractioned Heparin
• You can use mobilisation and compression stockings too

Question 16

How long does medicated treatment last for DVT?

Answer 16

Treatment lasts for at least 3 months but can extend to 6 months if the patient has cancer

Question 17

What are complications of DVT?

Answer 17

Pulmonary Embolism
Post Thrombotic Syndrome
Increased Risk of Bleeding