Sometimes known as economy class syndrome, deep vein thrombosis (DVT) is caused by the formation of a blood clot (thrombus) in the deep veins of the leg. The precise number of people affected by DVT and PE (pulmonary embolism) is unknown, although as many as 900,000 people could be affected (1 to 2 per 1,000) each year in the United States.
DVT occurs when a blood clot (thrombus) forms in one or more of the deep veins in your body, usually in your legs, groin or arm. It can cause swelling and pain in the leg, although it often occurs without any symptoms, and may have long-term consequences.
Blood clots are dangerous because they can break off and move with the flow of blood into the heart or lungs, where they can block major blood vessels and cause a potentially fatal pulmonary embolism.
The typical signs of deep vein thrombosis are:
Post-thrombotic syndrome (PTS) is also characterised by swelling, pain, discoloration, scaling in the affected limb and can result in leg ulcers development.
DVT leg symptoms can occur during long-haul flights. Aggravating factors are the low cabin pressure that increases the tendency of the blood to stagnate in the veins and low humidity that causes large amounts of body fluid to evaporate. As a result, the blood thickens even more, thereby increasing the likelihood of blood clots.
Several risk factors that increase the risk of developing a blood clot (thrombosis) have been identified, such as:
- Immobility (including prolonged inactivity, long trips by plane or car)
- Oral contraceptives
- Certain cancers
- Certain surgeries
- A family history of venous thrombosis (blood clots)
- Chronic inflammatory diseases
- High blood pressure
- High cholesterol
The most serious consequence of deep vein thrombosis is the development of fatal pulmonary embolism (PE). If a blood clot disconnects and travels in the circulation into an artery in the lung it can block the blood flow to part of the lung, leading to fatal PE.
Signs of PE can include:
- Shortness of breath
- Pain or discomfort in the chest
- Feeling dizzy or lightheaded
- Fast pulse
- Coughing up blood
Post-thrombotic syndrome (PTS), also called postphlebitic syndrome, is also a potential long-term complication of DVT. PTS reduces quality of life and has important socioeconomic consequences. Patients with severe PTS may even develop venous ulcerations.
Blood clots are among the most preventable types of blood conditions, and there are several ways to decrease the chances of developing DVT, such as controlling your risk factors wherever possible. If you think you are at risk because of family history or behavioral factors, consult your doctor. Also, make sure your doctor is aware of your complete medical history and any family history of blood clotting disorders. Check with your doctor for prevention measures such as JOBST medical compression stockings.
DVT Prophylaxis: What are the prevention measures?
Thrombosis prevention is also known as thrombosis prophylaxis. It comprises treatments that are designed to counteract the formation of blood clots inside blood vessels. These prevention measures often begin just after someone has had surgery, as this puts them at higher risk of having deep vein thrombosis, largely due to lack of movement afterward. Additionally, DVT (deep vein thrombosis) is often linked to air travel as sitting in confined spaces without moving for a long periods of time negatively influences the blood flow in the vessels.
Being aware of these common risk factors, and taking steps to avoid them, is an important part of helping to prevent thrombosis:
- Lack of exercise
- Taking oral contraceptives
- Being overweight/obese
- Long periods of inactivity, lying or sitting down, such as on long journeys (especially long-haul flights) or while in hospital
A risk assessment is a helpful way to begin DVT prophylaxis begin with a risk assessment. The risk assessment considers risk factors related to exposure (type of surgical procedure/trauma/acute disease, extent of immobilization) and disposition (individual inherited and acquired factors). In addition, the health status (diseases such as cancer, the age, dehydration, obesity, the VTE risk and the bleeding risk) influences the personal risk for DVT development.
There are several ways to help prevent thrombosis. For example, wearing compression stockings can help reduce swelling in tissues and promote better blood flow. In high-risk patients – such as hospitalized patients at increased risk of thrombosis who are bleeding, or are at high risk of major bleeding – medical compression stocking (MCS) (from 15 to 30 mmHg) and anticoagulant thromboprophylaxis are recommended. Medical compression stockings are especially recommended for thromboprophylaxis, if anticoagulants are contraindicated.
Their use is also suggested during long-distance travelling, to prevent DVT incidence in patients at risk. This is especially effective when combined with regular exercise during the journey, such as walking down the aisle and doing leg exercises.
Drug therapy is also a very common form of thrombosis prophylaxis. The use of compression stockings and medication can be supplemented with the simple technique of resting with your legs above the level of your heart. This can be done after surgery, for example, which assists in taking pressure off the legs and promotes the flow of blood out of the leg veins and to move throughout the body.