Home > Disease risk and advice > General advice > Deep Vein Thrombosis

Deep Vein Thrombosis

A deep vein thrombosis (DVT) is a blood clot in one of your body’s deep veins, usually in the lower leg, that can be caused by long periods of inactivity. A DVT can be potentially fatal if part of the clot breaks off and travels to the lungs, where it can cause a pulmonary embolism.

Who is at risk?
A DVT can follow any period of inactivity, for example after an operation, but can also happen spontaneously in healthy people or those with a more sedentary lifestyle, including office workers. The risk of DVT after long flights is now well documented, but the risk is similar after bus, car, and train journeys where there are long periods of immobilisation and inactivity. The risk is higher with longer journeys, particularly those over four hours and if you have certain health problems. Risk of DVT is increased in presence of other factors such as: previous DVT or family history of DVT, hormone replacement therapy use, pregnancy, recent surgery or trauma, cancer, obesity and some inherited blood-clotting abnormalities.

Signs and symptoms
The most common symptoms are pain, swelling and a heavy feeling in one of the legs. The area can be red and painful to touch and often occurs at the back of your calf, below the knee. If the vein gets completely blocked, the leg will become dark and swollen. The most common symptom of a pulmonary embolism is shortness of breath but can also include chest pain, coughing up blood and sudden collapse

If you experience any symptoms of either a DVT or a pulmonary embolism, you must seek immediate emergency medical treatment.

Anyone with a suspected DVT should be admitted to hospital where the main aim of treatment is to stop a DVT from developing into a pulmonary embolism. Treatment to reduce blood clotting is usually with an injection of an anticoagulant (anti-clotting) drug called heparin followed by a course of anticoagulant tablets. Treatment often takes several months. This allows for the use of newer oral anticoagulants which are becoming more commonly prescribed. You also need to wear properly fitted elastic compression stockings. 

Get advice from your doctor or specialist as soon as possible if you have a medical condition that increases your risk. You may need to be prescribed heparin injections to thin your blood and help prevent clots or be advised to wear properly fitted compression socks for long trips – fitted by a trained health professional, as badly fitting stockings can increase your risk of DVT.

During the journey
During the journey, it is important to avoid dehydration and not to wear restrictive clothes, especially around your waist or lower legs. Take frequent deep breaths, regularly flex and extend your ankles to encourage blood flow and try to stand and walk around as much as possible.

To see references and sources click here