Venous thromboembolism

• Virchow's triad is a set of three factors that increase the risk of blood clots in veins, also known as venous thrombosis or thromboembolism.

  A) stasis

  B) vessel wall injury

  C) hypercoagulability

  
• Risk factors for VTE:

  • Recent major surgery. 
  • Recent hospitilisation. 
  • Recent trauma. 
  • Chemotherapy.
  • Significant immobility (bedbound, unable to walk unaided or likely to spend a substantial portion of the day in bed or in a chair). 
  • Prolonged travel (for more than 4 hours). 
  • Significant trauma or direct trauma to a vein (for example intravenous catheter).
  • Hormone treatment (for example oestrogen-containing contraception or hormone replacement therapy). 
  • Pregnancy and the postpartum period. 
  • Dehydration.
• Multiple VTEs can occur because of:

  ·       Cancer

  ·       Inherited thrombophilia

  ·       Family history of thrombophilia

  ·       Antiphospholipid syndrome

  ·       Pregnancy with previous VTE