Updated COVID-19 Statement, Oct 20


About deep vein thrombosis

A deep vein thrombosis (DVT) is a blood clot which forms in the veins in the calf. A DVT is not dangerous in itself, but complications arising from it can be.

Complications occur when the clot breaks away from the vein wall and is carried along with the flow of blood. If the clot reaches a blood vessel which is too narrow for it to pass through, it forms a blockage. If this happens in the lungs it can be life threatening.

What are the symptoms?

Clots can be present without signs or symptoms, but often cause swelling and pain.

What can increase the chance of a DVT?

  • Length of travel eg. long haul flights
  • Not being able to move around
  • Cramped seating
  • Restrictive clothing
  • Reduced oxygen pressure and low humidity makes blood more sticky and likely to clot.

What can help prevent a DVT forming?

The wearing of compression hosiery has been shown to reduce the risk of a DVT developing. It is important to begin wearing hosiery at the start of a journey and for as long as it is practical at the end.

If you are on a plane try and walk about, drink lots of fluids avoiding alcohol and do simple leg exercises like rotating your ankles and flexing your feet. This helps blood flow up your legs to help prevent clotting.

Am I at risk of a DVT?

At Risk Group

  • Aged over 40
  • Very tall or very short
  • Previous or current leg swelling from any cause
  • Recent minor leg injury or minor body surgery
  • Extensive varicose veins

Higher Risk Group (and any of the previous factors)

  • Recent heart disease
  • Pregnant or on any hormone medication (contraceptive pill and HRT)
  • Recent major leg injury or leg surgery
  • Family history of DVT

Highest Risk Group (and any of the previous factors)

  • Previous or current DVT
  • Known clotting tendency
  • Recent major surgery or stroke
  • Current malignant disease or undergoing chemotherapy
  • Paralysed lower limb(s)

If you are at low risk of a DVT, as you are not in any of the groups above, an Activa® British Standard Class 1 sock would be appropriate.

Life after a DVT

If you have had a DVT, the damage to your veins can make you more likely to suffer with non-healing wounds (leg ulcers) or swelling.

It is important that you talk to your nurse or GP who may recommend you wear compression hosiery as a preventative measure.

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