Your interactive family guide to Spain as recommended by local mums | Last updated 7 months ago


Deep Vein Thrombosis (DVT)

DVT happens when a blood clot forms in a deep vein. DVT is most common in the deep veins of your lower leg (calf), and can spread up to the veins in your thigh. DVT can also first develop in the deep veins in your thigh and, more rarely, in other deep veins, such as the ones in your arm. Deep veins pass through the centre of your leg and are surrounded by a layer of muscle (see diagram). When blood clots form in the superficial veins, which lie just under your skin, the condition is known as superficial thrombophlebitis. These superficial blood clots are different to DVT and are much less serious.

  • Deep Vein Thrombosis
    Deep vein thrombosis (DVT)
    Published by Bupas health information team, June 2009

    Causes of DVT
    You are more likely to get a DVT if you:
    are over 40
    are immobile, for example, if you have had an operation (especially on a hip or knee) or are travelling for long distances - and so are not able to move your legs
    have had a blood clot in a vein before
    have a family history of blood clots in veins
    have a condition causing your blood to clot more easily (this is called thrombophilia)
    are very overweight (obese)
    have cancer or have had cancer treatment
    have heart disease or circulation problems
    are a woman taking a contraception pill that contains oestrogen, or hormone replacement therapy (HRT)
    are pregnant or have recently had a baby

    Symptoms and diagnosis
    Symptoms of DVT
    Many blood clots that cause DVT are small and dont produce any symptoms. Your body will usually be able to gradually break them down with no long-term effects.
    Larger clots can partly or completely block the blood flow in your vein and cause symptoms such as:
    swelling of the affected leg
    pain and tenderness in the affected leg - you may also find it difficult to stand properly with your full weight on the affected leg
    a change in the colour of your skin, for example, redness
    skin that feels warm or hot to the touch
    Although not necessarily a result of DVT, if you have these symptoms you should see a doctor.

    Diagnosis of DVT
    The doctor will ask about your symptoms and examine you. If he or she thinks that you might have a DVT, you may be referred to a specialist. You may have the following tests in hospital.
    A blood test called a D-Dimer. This measures a substance which develops when a blood clot breaks down. If this is negative its unlikely that you have a DVT.
    A Doppler ultrasound. This is a test that uses sound waves to look at your blood as it flows through your blood vessels. Its the best test to detect blood clots above your knee.
    A venogram. In this test, a special dye is injected into your vein, which shows up the vein on X-ray. This is the best way of showing clots below your knee.
    Please note that availability and use of specific tests may vary from country to country.

    Complications of DVT
    DVT may not cause you any further problems, but possible complications can include the following.
    Pulmonary embolism
    This is the most serious complication of DVT. A pulmonary embolism happens when a piece of the blood clot from a DVT breaks off and travels through your bloodstream to your lungs, where it blocks one of the blood vessels in your lungs. This is serious and in severe cases, can be fatal.
    Post thrombotic syndrome
    This is something that happens if DVT damages the valves in your deep veins, so that instead of flowing upwards, the blood pools in your lower leg. This can eventually lead to long-term pain, swelling and, in severe cases, ulcers on your leg.
    Limb ischaemia
    This is a rare complication that only happens in a very extensive DVT. Because of the blood clot, the pressure in your vein can become very high. This can block the flow of blood through your arteries, so less oxygen is carried to the affected leg. This can be painful and lead to skin ulcers, infection and even gangrene.

    Travel risks
    There is evidence that long-haul flights (lasting over four hours) can increase your risk of developing DVT. The risk is mainly the result of sitting down for long periods of time, which can happen during any form of long-distance travel, whether by car, bus, train or air.
    Its difficult to say whether the travelling itself directly causes DVT, or whether people who get DVT after travelling are at risk for other reasons. Generally, your risk of developing DVT when travelling is very small unless you have at least one of the other risk factors mentioned above (such as a history of DVT or cancer). If this is the case, you should talk to a doctor before you travel on a flight of more than four hours.

    Treatment of DVT
    Anticoagulant medicines are the standard treatment for DVT. They change chemicals in your blood to stop clots forming so easily. Anticoagulants include heparin and warfarin. Anticoagulants can stop new blood clots from forming and old ones from getting any bigger. They cant dissolve clots that you already have - your body will do that itself over time.
    Thrombolytic medicines are medicines that work by dissolving blood clots; but they can cause bleeding and so are rarely used to treat DVT.

    Compression stockings
    These are also called graduated compression stockings. Your doctor may ask you to wear these to ease your pain and reduce swelling, and to prevent post-thrombotic syndrome. You may need to wear them for two years or more after having a DVT.

    Availability and use of different treatments may vary from country to country. Ask your doctor for advice on your treatment options.

    Prevention of DVT
    Ask a doctor for advice if you think youre at risk of developing a DVT.
    There are a number of things you may be able to do to reduce your risk, such as stopping smoking if you smoke, or losing weight if youre overweight. Regular walking can help to improve the blood circulation in your legs and help to prevent another DVT from developing.
    There is no good evidence that taking aspirin reduces your risk of developing DVT.

    If youre having surgery
    Surgery and some medical treatments can increase your risk of developing DVT. So, if youre going to hospital for an operation, you may have an assessment to check your risk of developing DVT before you have your operation. There are many things that can be done to keep your risk of developing DVT during surgery as low as possible. You may be given anticoagulant medicines before and after surgery, or be asked to wear compression stockings. You may also be given a mechanical pump to use on
    your feet and legs in the first few days after the operation. This is called an intermittent compression device. The pump automatically squeezes your feet and lower legs to help your blood circulate.

    If youre travelling
    Although its unlikely that you will develop DVT when youre travelling, there are some steps you can take to reduce your chances of developing a blood clot. These include:
    take short walks - if youre a passenger, walk up and down the aisle of the coach, train or plane
    exercise the muscles of your lower legs, which act as a pump for the blood in your veins - regularly bend and straighten your toes, ankles and legs
    wear loose-fitting clothes
    keep hydrated by making sure you drink enough water
    dont drink too much alcohol or too many drinks that contain caffeine, such as coffee
    dont take sleeping tablets, as these will stop you keeping your legs active
    wear compression stockings if you have other risk factors for DVT

    If a doctor has told you that youre at high risk for DVT (for example, if you have a previous history of DVT or a blood clotting disorder), you may need heparin injections as well for flights longer than four hours. Talk to a doctor for more information.

    If you develop swelling or pain in your calf or thigh, or if you have breathing problems or chest pain after travelling, you should seek urgent medical attention.

    Thromboembolism. BMJ Clinical Evidence., accessed 23 January 2009
    Deep vein thrombosis. Clinical Knowledge Summaries., accessed 23 January 2009
    Advice on travel-related DVT. Department of Health., accessed 23 January 2009
    Wilson E. Preventing deaths from VTE in hospital 1: Risk factors. Nurs Times 103;(37): 26
    Longmore M, Wilkinson I, Turmezei T, et al. Oxford handbook of clinical medicine. 7th ed. Oxford: Oxford University Press, 2007: 596
    DVT and all that. Bandolier., accessed 23 January 2009
    Venous thromboembolism - reducing the risk of thromboembolism (DVT and pulmonary embolism) in in-patients undergoing surgery. National Institute for Health and Clinical Excellence (NICE). April 2007.
    WHO Research into global hazards of travel (WRIGHT) project. World Health Organisation., accessed 23 January 2009
    Simon C, Everitt H, Kendrick T. Oxford handbook of general practice. 2nd ed. Oxford: Oxford University Press, 2007: 364
    British Committee for Standards in Haematology Task Force. The diagnosis of deep vein thrombosis in symptomatic outpatients and the potential for clinical assessment and D-dimer assays to reduce the need for diagnostic imaging. Br J of Haematol, 2004; 124:15-25
    DVT and travel - brief update. Bandolier., accessed 24 January 2009
    Prophylaxis of venous thromboembolism. Scottish Intercollegiate Guidelines Network (SIGN) October 2002.
    Scurr JH, Machin SJ, Bailey-King S, et al. Frequency and prevention of symptomless deep-vein thrombosis in long-haul flights: a randomised trial. Lancet 2001;357: 1485-89

    This information was published by Bupas health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
    Publication date: June 2009