Deep veins occur deep within the body and include the internal jugular vein and veins within the arms and the legs. Veins in the calf or the thigh are most commonly affected by deep vein thrombosis, such as the femoral or popliteal veins.
What is a deep vein thrombosis?
A deep vein thrombosis (DVT) is a blood clot that occurs in a deep vein, such as the femoral vein in your leg. Deep veins lie deep within the body and carry most of the blood back to the heart, in contrast to superficial veins that are sited close to the skin's surface and carry minimal blood.
A clot in a deep vein can partially or totally obstruct blood flow. This causes the blood to pool and stagnate, stretching tissues and causing symptoms such as pain, cramping, and swelling.
What causes a deep vein thrombosis?
A blood clot is a gel-like mass that is composed of platelets and fibrin. Blood clots are our body’s way of stopping bleeding when an injury occurs to an artery or a vein; however, they can form inappropriately in unwanted areas for a variety of reasons, such as in people who:
- Are immobile for long periods (eg, on long-haul flights or long road trips) or bedridden due to illness or disease
- Are obese
- Are post-surgery and are unable to mobilize
- Take certain medications or hormones, such as birth control pills
- Have inherited blood clotting disorders or heart rhythm disturbances, such as atrial fibrillation
- Have high blood pressure
- Have high cholesterol
- Have other medical conditions, such as diabetes, cancer, or kidney disease
- Have broken bones or other types of trauma
People who have a personal or family history of DVT are more at risk.
What are the symptoms of a deep vein thrombosis?
Symptoms of DVTs vary depending on where the DVT has formed and may include:
- Pain, redness, and swelling in the affected area
- Skin discoloration. The skin overlying the DVT takes on a bluish, purplish or reddish tinge
- Skin that feels warm or dry to the touch
- A slight fever. This has been associated with an increased risk of complications, such as a pulmonary embolism (PE) (when a bit of the DVT breaks off and lodges itself in the lungs) or an infection
Symptoms of a pulmonary embolism (PE) vary depending on the extent of the area affected, and range from mild, barely noticeable chest discomfort and mild breathlessness, to sharp, severe chest pain, sudden breathlessness, a rapid heartbeat, and coughing up blood.
How is a deep vein thrombosis treated?
Treatment usually consists of an anticoagulant, which is a medicine that reduces the ability of your blood to clot, in effect "thinning" the blood. This helps prevent the DVT from getting bigger, reduces the risk of additional clots developing, and gives your body time to dissolve the clot. Treatment is usually required for at least three months. Examples of anticoagulants include apixaban, dabigatran, dalteparin, enoxaparin, heparin, rivaroxaban, and warfarin.
Clot busters (such as Tissue Plasminogen Activator, or TPA) may also be used in intensive care situations to break up severe clots.
Even though a DVT occurs in a deep vein, and heart attacks and strokes occur in arteries, a Danish study found a 60% increased risk of heart attack and a more than doubling of the risk of stroke within one year of a DVT episode.
The news was worse for people who had suffered a PE. Those with a history of PE were twice as likely to have a heart attack and three times more likely to have a stroke in the first year after a PE than people who had never had a PE.
How can a deep vein thrombosis be prevented?
Every hospital should focus on preventing DVTs in the first place. This means identifying at-risk patients before surgery or during their hospital stay and implementing measures such as mobilization, compression stockings, or use of medications to reduce the risk of a DVT forming.
Other ways to reduce the risk of developing a DVT include:
- Losing weight if you are overweight
- Not smoking
- Taking your medicines as prescribed, especially if you have certain conditions such as heart failure or atrial fibrillation
- Partaking in regular exercise