CIRCULATORY DISORDERS

Deep Vein Thrombosis (DVT)

Deep Vein Thrombosis is a condition in which a blood clot (thrombus) forms in one or more of the deep veins in the body, usually in the legs.

Deep Vein Thrombosis is a serious condition because a blood clot that has formed in the vein can break loose and travel to the lungs. This is called Pulmonary (lung) Embolism.

CAUSES

Several factors contribute to clot formation, including:

* Slow blood flow, often due to lying or sitting still for an extended period of time

* Pooling of blood in a vein, often due to:

a)Immobility

b)Medical conditions

c)Damage to valves in a vein or pressure on the valves, such as during pregnancy

* Injury to a blood vessel

* Clotting problems (can occur due to aging or disease)

* Catheters placed in a vein

RISK FACTORS

* Not moving the body.Sitting for long periods of time, such as when driving or flying.

* Hospitalization

* Surgery, especially involving bones or joints

* Medical conditions such as:

a)Varicose veins

b)Cancer

c)Heart failure

d)Heart attack

e)Inflammatory bowel disease

f)Blood disorders

* Obesity

* History of deep vein thrombosis

* Taking birth control pills or estrogen therapy

* Pregnancy

SYMPTOMS

Symptoms occur when:

* The clot interferes with blood flow in the vein

* Local inflammation occurs

* A clot breaks free and travels to the lungs

Some patients may not experience any symptoms until the clot moves to the lungs, a condition called Pulmonary Embolism.

Symptoms of Deep Vein Thrombosis may include:

* Pain

* Swelling of a limb

* Tenderness along the vein

* Warmth

* Redness, paleness, or blueness of the skin of the affected limb.

DIAGNOSIS

Tests may include:

DUPLEX VENOUS ULTRASOUND – a test that uses sound waves to detect changes in blood flow.

VENOGRAPHY – X-rays taken after dye is injected into a small vein to show areas of normal and abnormal blood flow.

IMPEDANCE PLETHYSMOGRAPHY – measures changes in blood volume in the veins as a blood pressure cuff wrapped around the thigh is inflated and deflated.

TREATMENT OF DEEP VEIN THROMBOSIS

Treatment aims to:

* Prevent Pulmonary Embolism

* Stop the clot from growing

* Dissolve the clot (sometimes)

Treatments include:

SUPPORTIVE CARE

This may include:

* Resting in bed

* Elevating the affected limb above the heart

* Wearing compression stockings as recommended by the doctor.

MEDICATIONS

Anticoagulant drugs to prevent additional clot formation include:

* Heparin injection – fast-acting drug that prevents more clot formation (given for several days)

* Warfarin (taken by mouth) – slowly prevents more clot formation (usually given for several months)

* Fibrinolytic enzymes – helps to dissolve a major clot. These include:

a)Streptokinase

b)Urokinase

c)TPA

SURGERY

In certain situations, doctors may place a filter in the inferior vena cava, a major vein returning blood from the lower body to the heart. The filter may trap any clots that break loose and travel toward the lungs.

PREVENTION

General prevention measures include:

* Not sitting for long periods, such as in a car or airplane or at a computer (Get up frequently and move around.)

* Not smoking

If you are admitted to the hospital, talk to your doctor about how to prevent blood clots, such as:

* Getting out of bed and walking as soon as possible during your recovery

* If you are restricted to bed:

- Doing range of motion exercises in bed

- Changing your position at least every two hours

* Wearing compression stockings, which promotes venous blood flow.

* Taking anticoagulant medication if advised by your doctor.

* Using a pneumatic compression device (a device that uses air to compress your legs and help improve venous blood flow).