VTE

• Patients with an artificial valve should be offered a Vitamin K antagonist (warfarin) for anticoagulation
• A DVT is a venous thrombus that has formed in the deep veins of the lower extremities
• Virchow‘s triad = hyper-coagulability, stasis and endothelial injury
• Clinical features of DVT are almost always unilateral:

  • calf or leg swelling
  • dilated superficial veins
  • calf tenderness
  • warmth
  • oedema - more than 3cm difference in calves
• Strong risk factors for DVT:

  • major surgery
  • trauma
  • absolute bed rest
• The wells score is used to calculate the probably of DVT:

  • 2 or more points = DVT likely
  • 1 or less points = unlikely
• Investigations:

  • D- dimer - fibrin degradation product
  • doppler USS of leg
• • DVT unlikely - d-dimer can exclude DVT - if d-dimer positive proceed to USS
  • DVT likely - d-dimer and USS - if d-dimer raised and USS negative repeat in a week
  • offer interim anticoagulation if USS cannot be performed within 4 hours
• Treatment for DVT or PE:

  • anticoagulation for at least 3 months
  • first line - DOAC e.g. apixaban
  • severe renal impairment - LMWH
• ORBIT score is used to monitor the risk of bleeding on long term anticoagulation
• PE is a embolus is the pulmonary arteries, usually from a DVT
• Symptoms of a PE:

  • SOB
  • pleuritic chest pain
  • cough
  • haemoptysis
  • dizziness/syncope
• Clinical signs of a PE:

  • hypoxia
  • tachycardia
  • tachypnoea
  • low grade fever
  • hypotension
  • signs of DVT
  • can cause acute cor pulmonale - raised JVP
• The 2 level PE wells test is used to score the probability of a PE:

  • more than 4 points = PE likely
  • 4 or less points = PE unlikely
• Investigations for PE:

  • ABG - hypoxia
  • ECG - most commonly sinus tachycardia
  • CXR - normal in most cases
  • CTPA
• • If a PE is likely - proceed to CTPA
  • if a PE is unlikely - do d-dimer and proceed to CTPA if d-dimer positive
  • offer interim anticoagulation if d-dimer or CTPA is delayed
• A V/Q scan can be performed instead if the patient is pregnant, has a renal impairment or contrast allergy
• If a patient has a massive PE and is haemodynamically unstable:

  • continuous infusion of unfractionated heparin
  • consider thrombolysis - streptokinase and alteplase
• Treatment length:

  • Provoked DVT or PE = at least 3 months
  • Unprovoked DVT or PE = 6 months
  • Active malignancy = 6 months
  • Recurrent DVT or PE = life long