What is Deep Vein Thrombosis and Thrombophlebitis?

Deep vein thrombosis (DVT) and thrombophlebitis are conditions that involve formation of blood clot (thrombus) in the veins. In 90% of cases, these conditions occur in the leg; however, they also occasionally occur in the arms or, even more rarely, in other parts of the body.

Thrombophlebitis refers to blood clot in the superficial veins (those closer to the skin surface). It can be caused by irritation of the inner wall of the vein after phlebotomy or insertion of an intravenous line. Thrombophlebitis can also occur as a complication of varicose veins. While there is a risk of the blood clot traveling into the deep veins, serious complications due to superficial thrombophlebitis are uncommon. If the blood clot becomes infected, it is called a septic thrombophlebitis. Patients with this condition develop fevers and redness of the skin over the blood clot.

A DVT is a blood clot in a deep vein within the muscle of the leg. Each year, 800,000 people in the United States are diagnosed with DVT. DVT may result from prolonged bed rest or activity restriction. DVT is associated with long plane rides or car rides. Frequent business travelers are estimated to have a 5% per year risk of DVT. Other potential contributing causes for DVT are pregnancy, obesity, advanced age, dehydration, smoking, recent major illness or major surgery, and use of birth control pills or hormone replacement. Some people with DVT have an underlying hypercoagulable state (an increased tendency to clot the blood), and an estimated 20 percent have an occult malignancy.

The most significant danger of DVT is that the blood clot dislodges and travels through the veins to the heart and lungs, causing a pulmonary embolism (PE). Although not a common complication of DVT, PE is fatal in 30-50% of cases. DVT can also result in deep venous incompetence (damage to the valves in the veins), which increases risk of chronic venous stasis disease (CVSD), cellulitis, and skin ulcers. A third of people with DVT will develop CVSD, chronic skin changes which produce leg edema, discoloration, and leg discomfort.

How are DVT and Thrombophlebitis Diagnosed?

Thrombophlebitis often causes tenderness and discoloration of the skin over the area of the affected vein. The vein may also feel hard and thick, like a piece of rope. Some people experience localized swelling, warmth and redness over the vein. These symptoms may be accompanied by fever if the vein is infected.

Swelling of the leg is the most common symptom of DVT. Some people may also experience a feeling of fullness in the leg. Doctors diagnose DVT with the use of an ultrasound which reveals the location and extent of a DVT. Sudden swelling of a leg or arm is an urgent medical condition and should be evaluated promptly by a physician.

How are Thrombophlebitis and DVT Treated?

Treatment for thrombophlebitis generally involves self-care techniques, such as the application of heat, rest and elevation of the leg. Non-steroidal anti-inflammatory medications such as ibuprofen may be helpful, and antibiotics may be prescribed if signs of infection are present. Varicose vein surgery may be recommended if the thrombophlebitis results from varicose veins.

“Blood thinners” are used to treat DVT. These medications help to prevent the blood clot from enlarging and prevent new clots from forming. They also help to stabilize the blood clot, decreasing risk of PE. The medication may initially be given by injection (lovenox, or low molecular weight heparin) will transitioning to oral medication (warfarin). Warfarin may be continued for 3 to 12 months, or may be continued indefinitely in patients who are at high risk for recurrent DVT or PE. Patients are encouraged to walk and to avoid prolonged standing or sitting. Elevating the legs helps to reduce swelling. Compression stockings are prescribed to decrease risk of progressive venous stasis disease and complications such as cellulites (skin infection) or ulceration.

Placement of a inferior vena caval (IVC) filter may be considered in patients with large DVTs in order to decrease risk of PE. The filter is a small metal screen which is positioned in the main vein in the abdomen (the IVC) to “trap” clot traveling from the legs to the heart and lungs. It is placed through a needle stick in the neck or groin. In most cases, the procedure takes less than 30 minutes. Some filters are designed to be removed later; others are left in permanently.

In some patients, DVT can be treated with a minimally-invasive procedure to dissolve and remove clot. Medication to dissolve clot (thrombolytic) is administered through an occillating catheter inserted into the vein through a needle stick behind the knee or in the groin. The clot fragments are removed by applying suction. This technique may help preserve the function of the valves within the veins and help decrease the risk of post-thrombotic syndrome. The DVT must be diagnosed early (ideally within 6 weeks of onset) for this type of treatment to be effective.