Overview of thrombosis
A thrombosis occurs when a blood clot (thrombus) forms within a blood vessel and obstructs the normal flow of blood through the circulatory system. Whenever a blood vessel is damaged, your body uses a combination of platelets (thrombocytes) and fibrin to create a blood clot, which serves to prevent blood loss. Certain circumstances can trigger this process, even when there is no damage. Any blood clot that forms and then starts to circulate around the body in the bloodstream is described as an embolus.
Deep vein thrombosis (DVT) may result in leg pain or swelling, but can also occur without any obvious symptoms. DVT may also become an issue with any condition that affects blood clotting. Likewise, DVT may become a risk if you are immobilised for a long period, such as when you are confined to bed in hospital.
Symptoms of thrombosis
In some instances, there may be no symptoms, but deep vein thrombosis signs and symptoms may often include:
- swelling of the affected leg (less often, there could be swelling in both)
- a leg pain, which usually starts in the calf and may seem like a cramp or soreness
- warm skin around the location of the clot
- a heavy ache in the affected region
Contact your doctor for advice if you develop any signs or symptoms of deep vein thrombosis. If left untreated, there is a chance that around one in 10 people with DVT may then develop a pulmonary embolism. This is a serious condition with symptoms that include:
- the unexplained onset of breathlessness (sudden or gradual)
- chest pain or discomfort, which gets worse as you breathe in or cough
- a light-headed, dizzy or fainting sensation
- a rapid pulse
- the coughing of blood
Should you develop any signs or symptoms of a pulmonary embolism — a life-threatening complication of DVT — seek medical attention at once.
Causes of thrombosis
When a blood clot forms in one of your body’s deep veins, often in your leg, the result is deep vein thrombosis (DVT). Blood clots may be caused by anything that prevents normal blood circulation or normal blood clotting.
There are a number of risk factors associated with DVT and blood clotting. These include:
- prolonged hospital bed rest
- injuries or surgical procedures
- HRT therapy or oral contraceptives (birth-control pills)
- obesity and being overweight
- certain forms of cancer
- heart failure
- inflammatory bowel disease
- a family history of DVT or pulmonary embolism
- age – those over 60 are at greater risk
- inactivity and sitting for long periods of time
Diagnosis of thrombosis
Your doctor will want to know about your symptoms and medical history.
In many cases, an accurate diagnosis may require one or more of the following test procedures:
- D-dimer blood test – this can reveal any fragments of blood clots floating loose in your bloodstream. A considerable number increases the likelihood your vein contains a blood clot.
- Ultrasound scan – often used to support a D-dimer test, an ultrasound scan will detect the rate at which your blood flows through a blood vessel. This helps identify any unusually slow flow rates, which could indicate a problem involving a blood clot.
- Venogram – this procedure may be called upon if the D-dimer and ultrasound investigations are inconclusive. A venogram involves introducing a dye into a vein in your foot. As the dye spreads, an X-ray can locate the point at which a clot is preventing normal blood flow.
Treatment of thrombosis
DVT treatments aim to stabilise existing clots, prevent further clots developing, and reduce your chance of experiencing another DVT episode.
The available DVT options include:
- blood thinners and anticoagulants – these include drugs such as heparin and warfarin. Medication instructions should be carefully followed and you will need blood tests to monitor your recovery.
- clotbusters – these powerful drugs are sometimes used to disperse blood clots in life-threatening situations.
- IVC filters – these filters can be inserted inside a large vein in order to trap blood clot fragments.
- compression stockings – wearing these can play a part in preventing the swelling that is associated with DVT, and will reduce the likelihood of further clotting.
Chances of recovery from thrombosis
Over the long term, most people make a complete recovery from DVT. There is some risk of a further episode but this can be controlled with preventive measures.
Prevention of thrombosis
Typical preventive measures for DVT can include:
- wearing compression stockings.
- taking all medication as advised. This, of course, includes additional medication prescribed to protect you during hospital procedures.
- Anticipating, minimising or avoiding long periods of inactivity.
- Exercising regularly, giving up smoking and monitoring your weight.