Venous Thrombombolism

Question 1

Definition

Answer 1

• Thrombosis developing in circulation which usually occurs secondary to stagnation of blood and hyper-coagulable states
• When it develops in the venous circulation it is called a DVT - this can then embolise to the pulmonary arteries causing a PE

Question 2

Risk factors

Answer 2

• Immobility
• Recent surgery
• Long haul flights
• Pregnancy
• Hormone therapy with oestrogen (combined oral contraceptive pill and hormone replacement therapy)
• Malignancy
• Polycythaemia
• Systemic lupus erythematosus
• Thrombophilia
  
  • Antiphospholipid syndrome
  • Antithrombin deficiency
  • Protein C or S deficiency
  • Factor V Leiden
  • Hyperhomocysteinaemia
  • Prothombin gene variant
  • Activated protein C resistance

Question 3

VTE prophylaxis

Answer 3

• LMWH (i.e. enoxaparin) unless contraindicated by existing anticoagulation
• Anti-embolic compression stockings unless contraindicated by PAD

Question 4

Presentation of DVT

Answer 4

• Unilateral
• Calf or leg swelling (>3cm difference betwen calves)
• Dilated superficial veing
• Tenderness of the calf (particularly over deep venous system)
• Oedema
• Colour changes to leg

Question 5

Diagnosis of DVT

Answer 5

• Wells score predicts risk
• D-dimer is sensitive but not specific
• US doppler of leg required to diagnose
• CTPA or VQ scan for PE

Question 6

Management of DVT

Answer 6

• LMWH
• Switch to long term anticoagulation with warfarin (target INR 2-3) or NOACs
• IVC filter - in unusual cases of recurrent PEs

NB - If pregnancy LMWH for 3 months if reversible cause or 6 months if not. In cancer LMWH for 6 months then review.