Deep venous thrombosis (DVT) and Thrombophlebitis
A clot in the veins is called a deep venous thrombosis (DVT) when it is in the deep veins within the muscle and superficial thrombophlebitis when it is in the veins outside the muscle just under the skin surface. Both types of clots generally occur in the veins of the leg, but about 10-15% occur in veins of the arms or elsewhere (neck, pelvis, chest wall).
Superficial thrombophlebitis can occur after a blood draw or IV. It is also not unusual to get clots in a cluster of large varicose veins. In general, superficial thrombophlebitis is not dangerous, just painful until it resolves. Sometimes, a thrombophlebitis can leave behind a darkened area on the skin (hyperpigmentation). Rarely, more serious complications can occur, like infection in the clot (septic thrombophlebitis) or extension of clot into the deep veins.
A superficial thrombophlebitis will feel like a hard, tender lump in the vein, or like a rope underneath the skin surface. Often the skin over the top of the vein is red and inflamed. Fever or shaking skills indicates infection.
Typically the treatment is anti-inflammatory medication like ibuprofen, moderate activity, and warm compresses. Referral to a vascular specialist is often advised to discuss treatment of the varicose veins to prevent future similar episodes. For more on treatment of varicose veins, click here.
DVT is a more worrisome problem because clots in the deep vein system can dislodge and travel through the veins to the heart and lungs, causing a pulmonary embolism (PE). Although only a small number of DVT result in PE, PE is fatal in 30-40% of cases. DVT can also cause permanent damage to the valves in the leg veins, resulting in deep venous insufficiency (DVI), or pooling of blood in the legs. DVI leads to edema (swelling), discoloration of the skin in the lower leg, and leg discomfort (aching, throbbing, tightness or a feeling of engorgement). A third of people with DVT will develop chronic venous stasis disease (CVSD), skin damage which can lead to skin infection and ulcers.
DVT usually are manifest as deep, persistent pain in the calf muscle or thigh muscle. People often describe it as like a Charley horse. Sudden onset of chest pain or shortness of breath may be a sign of a pulmonary embolus.
Most DVT result from periods of inactivity, when the calf muscle is not moving and the blood in the veins of the legs is stagnant. Examples of this are long plane rides or car rides, surgical procedures or periods of time when the leg is in a cast or is immobilized. Other predisposing factors for DVT include: active smoking, use of birth control or other hormonal replacement, extreme dehydration, obesity, and pregnancy. Some people with DVT have an inherited or acquired tendency to clot the blood, something we call a hypercoagulable state. In some cases when there is a strong family history of clotting problems or when the DVT is unprovoked (no other risk factors), we may recommend a hypercoagulable state evaluation (a series of specialized blood tests) and referral to a hematologist. DVTs are also associated with cancer and cancer treatment. A certain percentage of people with DVT have an occult (not yet detected) malignancy. For this reason, we remind all people with DVT to consider routine cancer screening exams (mammography, colonoscopy, prostate exam).
Blood thinners are a mainstay in treatment for DVT. Warfarin(coumadin) is the most widely used oral medication for this purpose, but the medication may take several days to reach an appropriate level in the bloodstream. Usually, patients are started on a medication given by injection (Lovenox or Enoxaparin) which acts immediately, until the warfarin reaches full effect. Blood tests called protime (PT) and INR must be checked periodically in order to ensure that the warfarin level is appropriate. The level may vary dependent on diet, exercise, and other medications. Other oral anticoagulants are being studied currently to be used as alternatives to warfarin.
Some people with DVT may be good candidates for clot thrombolysis, a procedure to remove clot surgically. For more on procedures for DVT, click here.