The condition can be life threatening if the clot dislodges from the vein and travels to the lungs, where it can completely block blood flow.
Causes of Venous Blood Clots
Blood clots in the veins are usually caused by slowed blood flow to the legs and feet, which can cause the blood to clot, or by damage to a vein caused by injury or infection. Blood flow may be slowed because of physical inactivity – being confined to a bed or leading a sedentary lifestyle. Some persons experience slowed blood flow after sitting for long periods of time. Other contributors to slowed blood flow to the legs and feet include smoking, heart disease, diabetes, high blood pressure, and certain tumors. The use of certain hormones, particularly estrogen, and pregnancy have been shown to increase the risk for blood clots in the legs. Genetic disorders may also predispose a person to develop venous blood clots.
Symptoms of Venous Blood Clots
Blood clots that occur in veins located close to the surface of the skin may cause mild inflammation, tenderness and redness. Symptoms of deep venous clots may include:
- Swelling of the ankles or calves.
- Tenderness, as well as swelling, redness, and warmth around the affected area.
- Discomfort when the foot is raised upwards.
Physicians can usually identify the condition by pressing on a part of the leg. If necessary, the veins can be viewed by ultrasound, a technique that uses sound waves to create an image of the vein on a screen. Clots above the knee may be identified by using a blood pressure cuff around the leg to measure blood flow (plethysmography). Deep venous blood clots in areas other than the leg may be impossible to detect by these methods, and a diagnosis may require special techniques such as X–rays of the veins or blood–clotting tests.
Treatment of Venous Blood Clots
Treatment depends on the cause of the blood clot. In most cases, a blood–thinning agent or anti–coagulant medication will be prescribed. Persons will need to stay in bed and keep their legs elevated for 3 to 5 days. Moist heat and medications can reduce swelling and pain.
For those who have had a clot in their lungs or those who cannot take anticoagulants, a catheterization procedure may be performed to prevent further clots. A tiny filter is guided by a catheter to the vein that carries blood from the legs to the lungs. Once the filter is permanently in place, it can prevent clots from reaching the lungs.
Pulmonary Embolism
Pulmonary embolism is caused by a blood clot (pulmonary embolus) that dislodges from where it forms– in a vein and travels to the lungs.
Symptoms of Pulmonary Embolism
Pulmonary embolism may have no symptoms, so it can cause sudden, unexpected death. When symptoms do occur, they may include:
- Chest pain, especially upon inhaling.
- Shortness of breath.
- Coughing up blood.
- Dizziness.
- Fainting.
Physicians will begin by checking the oxygen levels in the blood in the arteries – a low level may indicate an embolus in the lungs. The diagnosis is usually confirmed by radioisotope scanning. Follow–up evaluation may include pulmonary angiography, a catheter procedure in which dye is injected to reveal blood flow through the lungs.
Treatment of Pulmonary Embolism
Most cases of pulmonary embolism are treated with blood–thinning agents, anticoagulants, and clot–dissolving drugs (thrombolytic therapy). Surgery may be needed in rare cases to remove the clot, but most patients respond positively to drug therapy.
Phlebitis
There are two forms of phlebitis. The most common form is an inflammation of a vein near the skin’s surface, usually in the leg (superficial phlebitis). Inflammation of the interior veins of the leg (deep phlebitis) is less common but more serious. For superficial phlebitis, the area looks reddish and feels painful. The pain associated with this condition can usually be treated with moist heat, aspirin, or anti–inflammatory medication.
The more dangerous form of phlebitis, deep phlebitis, usually causes greater pain, and persons tend to have a fever. Nuclear scans, venous Doppler flow studies, or the use of a blood pressure cuff around the leg to measure blood flow (plethysmography) will usually confirm if the deep veins are involved. This type of phlebitis is more likely to lead to clot formation in the veins and a possible pulmonary embolus. If you are diagnosed with deep phlebitis, doctors will usually prescribe a one–week treatment with an anti–coagulant. The medication is given intravenously, so you will be hospitalized. During this time, doctors will also check for signs of pulmonary emboli. After you leave the hospital, your doctor will probably prescribe an oral anticoagulant to be taken longer–term.
Varicose Veins
Varicose veins are swollen, purple veins in the legs that are visible under the skin. They are caused by damage to superficial blood vessels, slowed blood flow, or damage or absence of normal valves in the veins. Normally, blood circulation in the veins is aided by valves, which keep the blood moving upward, against the force of gravity. If these valves are weak or blood flows slowly in the veins, the blood may pool and cause the veins to bulge.
Varicose veins are more common in women than men. The condition also occurs in some families more than others, suggesting a hereditary factor. Pregnant women may develop varicose veins because of hormonal changes and the extra pressure that the fetus puts on the abdomen. They may also be caused by being severely overweight or by standing for long periods.
Symptoms of Varicose Veins
The most obvious symptom is the appearance of blue or purple snakelike veins. They occur near the skin and may stand out from the legs. Clusters of flooded capillaries called “Spider veins” sometimes surround varicose veins. Varicose veins may cause the legs to ache or have a tingling discomfort, and the ankles may swell at the end of the day. In most cases, however, those who seek treatment for varicose veins do so because they find them unattractive.
Treatment of Varicose Veins
In the early stages, a supportive, elastic stocking may relieve the aching and swelling, but it does not cure the condition.
Repair may involve injecting a salt solution that causes the veins to shrink. Another option for repairing varicose veins is injecting a fluid (known as a sclerosing agent) that inflames the vein wall. The leg is then bandaged tightly to keep the walls of the veins close together. The resultant scarring causes the walls of the vein to stick together. Surgical repair, called “Stripping”, involves tying the varicose veins at certain intervals and removing the affected portion of vein. The body responds by creating new circulatory pathways.