DVT

• What is the development of DVT related to?

  Virchow's triad

  • hypercoagulability
  • endothelial dysfunction/damage
  • venous stasis
• What can cause hypercoagulability?


  Hereditary causes

  • Factor V Leiden
  • Anti-thrombin 3 deficiency
  • Protein C/S deficiency

  Acquired causes

  • Malignancy
  • COC
  • HRT
  • Pregnancy
• What may cause endothelial dysfunction/damage?

  Dysfunction → due to HTN or effects of smoking

  Damage → trauma or central venous access lines
• What causes venous stasis?


  Usually immobilisation
• What should be carried out if DVT is suspected?


  DVT Well's score

  • Active cancer = +1
  • Paralysis, paresis or recent plaster immobilisation of lower extremities = +1
  • Recently bedridden or major surgery within 12 weeks = +1
  • Localised tenderness along deep venous system = +1
  • Entire leg swollen = +1
  • Calf swelling at least 3cm larger than asymptomatic side = +1
  • Pitting oedema confined to symptomatic leg = +1
  • Collateral superficial veins = +1
  • Previously documented DVT = +1
  • Alternative diagnosis is at least as likely as DVT = -2

  >/= 2 = DVT likely

  < 1 = DVT unlikely
• What are the DDx of DVT?


  Cellulitis

  Superficial thrombophlebitis

  Dependent oedema

  Liver cirrhosis

  Nephrotic syndrome

  Ruptured Baker's cyst

  Trauma
• What are the RFs of DVT?


  Male

  Over 60

  Immobilisation

  Inflammatory state (vasculitis, sepsis)

  Malignancy

  Medication (chemotherapy, HRT/COC)

  Obesity

  Pregnancy

  Previous VTE

  Recent surgery or trauma

  Smoking

  Varicose veins
• What are the signs & symptoms of DVT?


  Unilateral leg pain

  Unilateral leg swelling

  Skin changes of affected leg (from pallor to cyanosis to diffuse erythema)

  Increased temp of affected leg

  Tender calf

  Difference size in the calves (> 3cm, measured 10cm below tibial tuberosity)
• What are the possible complications of DVT?


  PE

  Post-thrombotic syndrome (PTS)
• What is the treatment of DVT?


  Anticoagulation

  • apixaban or rivaroxaban (1st line)
  • If neither are suited → either LMWH followed by dabigatran or edoxaban OR LMWH followed by vitamin K antagonist (VKA)
  • If pt has severe renal impairment → LMWH, unfractionated heparin or LMWH followed by VKA
  • If pt has antiphospholipid syndrome → LMWH followed by VKA
• What is the length of anticoagulation for DVT?


  If obvious RF -> 3 months (3-6 months for pts with active cancer)

  If no obvious RF -> 6 months