DEEP VEIN THROMBOSIS - DVT

What Is Deep Vein Thrombosis?

Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Blood clots occur when blood thickens and clumps together.
Most deep vein blood clots occur in the lower leg or thigh. They also can occur in other parts of the body.
A blood clot in a deep vein can break off and travel through the bloodstream. The loose clot is called an embolus. When the clot travels to the lungs and blocks blood flow, the condition is called pulmonary embolism, or PE.
PE is a very serious condition. It can damage the lungs and other organs in the body and cause death.
Blood clots in the thigh are more likely to break off and cause PE than blood clots in the lower leg or other parts of the body.
Blood clots also can form in veins closer to the skin's surface. However, these clots won't break off and cause PE.

What are the Causes?

Deep venous thrombosis (DVT) mainly affects the large veins in the lower leg and thigh. The clot can block blood flow and cause swelling and pain. When a clot breaks off and moves through the bloodstream, this is called an embolism. An embolism can get stuck in the brain, lungs, heart, or other area, leading to severe damage.
Blood clots may form when something slows or changes the flow of blood in the veins.

Risk factors include:

• After a pacemaker catheter has been passed through the vein in the groin
• Bedrest
• Cigarette smoking
• Fractures in the pelvis or legs
• Giving birth within the last 6 months
• Heart failure
• Medications such as estrogen and birth control pills
• Obesity
• Recent surgery (especially hip, knee, or female reproductive organ surgery)
• Too many blood cells being made by the bone marrow (polycythemia vera), causing the blood to be thicker and slower than normal

You're also more likely to develop DVT if you have any of the following conditions:

• Blood that is more likely to clot (hypercoagulability)
• Cancer
• Taking estrogens or birth control pills. This risk is even higher if you smoke.

DVTs are most common in adults over age 60, but can occur at any age.
Sitting for long periods when traveling can increase the risk of DVTs. This is most likely when one or more of the risk factors listed above are also present.

What are the Symptoms?

• Changes in skin color (redness) in one leg
• Increased warmth in one leg
• Leg pain in one leg (it may hurt to place all of your weight on this leg when standing)
• Leg tenderness in one leg
• Skin that feels warm to the touch
• Swelling (edema) of one leg

Exams and Tests

Your doctor will perform a physical exam. The exam may show a red, swollen, or tender leg.
The following tests may be done:

• Doppler ultrasound exam of a limb
• D-dimer blood test
• Plethysmography of the legs
• X-rays to show veins in the affected area(venography)

Blood tests may be done to check if there is increased chance of blood clotting (hypercoagulability). Such tests include:

• Activated protein C resistance (checks for the Factor V Leiden mutation)
• Antithrombin III levels
• Genetic testing to look for mutations that make you more likely to develop blood clots, including the prothrombin G20210A mutation
• Lupus anticoagulant or antiphospholipid antibodies
• Protein C and protein S levels
• Screening for disseminated intravascular coagulation (DIC)

This list is not all-inclusive.

Treatment

Deep vein thrombosis (DVT) is treated with medicines and other devices and therapies. The main goals of treating DVT include:

• Stopping the blood clot from getting bigger
• Preventing the blood clot from breaking off and moving to your lungs
• Reducing your chance of having another blood clot

Medicines

Medicines are used to prevent and treat DVT.

Anticoagulants

Anticoagulants are the most common medicines for treating DVT. They're also known as blood thinners.
These medicines decrease your blood's ability to clot. They also stop existing blood clots from getting bigger. However, blood thinners can't break up blood clots that have already formed. (The body dissolves most blood clots with time.)

Blood thinners can be taken as either a pill, an injection under the skin, or through a needle or tube inserted into a vein (called intravenous, or IV, injection).

Warfarin and heparin are two blood thinners used to treat DVT. Warfarin is given in pill form. (Coumadin  is a common brand name for warfarin.) Heparin is given as an injection or through an IV tube. There are different types of heparin. Your doctor will discuss the options with you.

Your doctor may treat you with both heparin and warfarin at the same time. Heparin acts quickly. Warfarin takes 2 to 3 days before it starts to work. Once the warfarin starts to work, the heparin is stopped.
Pregnant women usually are treated with just heparin because warfarin is dangerous during pregnancy.

Treatment for DVT using blood thinners usually lasts from 3 to 6 months. The following situations may change the length of treatment.

• If your blood clot occurred after a short-term risk (for example, surgery), your treatment time may be shorter.
• If you've had blood clots before, your treatment time may be longer.
• If you have certain other illnesses, such as cancer, you may need to take blood thinners for as long as you have the illness.

The most common side effect of blood thinners is bleeding. This happens if the medicine thins your blood too much. This side effect can be life threatening.

Sometimes, the bleeding is internal (inside your body). People treated with blood thinners usually have regular blood tests to measure their blood's ability to clot. These blood tests are called PT and PTT tests.
These tests also help your doctor make sure you're taking the right amount of medicine. Call your doctor right away if you have easy bruising or bleeding. These may be signs that your medicines have thinned your blood too much.

Thrombin Inhibitors

These medicines interfere with the blood clotting process. They're used to treat blood clots in patients who can't take heparin.

Thrombolytics

These medicines are given to quickly dissolve a blood clot. They're used to treat large blood clots that cause severe symptoms.
Because thrombolytics can cause sudden bleeding, they're used only in life-threatening situations.

Other Types of Treatment

Vena Cava Filter

A vena cava filter is used if you can't take blood thinners or if you're taking blood thinners and still developing blood clots.
The filter is inserted inside a large vein called the vena cava. The filter catches blood clots that break off in a vein before they move to the lungs. This prevents pulmonary embolism. However, it doesn't stop new blood clots from forming.

Graduated Compression Stockings

These stockings can reduce the swelling that may occur after a blood clot has developed in your leg. Graduated compression stockings are worn on the legs from the arch of the foot to just above or below the knee.
These stockings are tight at the ankle and become looser as they go up the leg. This creates gentle pressure up the leg. The pressure keeps blood from pooling and clotting.
There are three types of compression stockings. One type is support pantyhose. These offer the least amount of pressure.
The second type is over-the-counter compression hose. These stockings give a little more pressure than support pantyhose. Over-the-counter compression hose are sold in medical supply stores and pharmacies.
Prescription-strength compression hose are the third type of compression stockings. These stockings offer the greatest amount of pressure. They also are sold in medical supply stores and pharmacies. However, you need to be fitted for them in the store by a specially trained person.
Talk with your doctor about how long you should wear compression stockings

Outlook (Prognosis)

Many DVTs disappear without a problem, but they can return. Some people may have long-term pain and swelling in the leg known as post-phlebitic syndrome. Wearing tight (compression) stockings during and after the DVT may help prevent this problem.
Blood clots in the thigh are more likely to break off and cause pulmonary embolism (PE) than blood clots in the lower leg or other parts of the body.

Possible Complications

A blood clot can break free in the leg and travel to the lungs (pulmonary embolus) or anywhere else in the body, and can be life threatening. Rapid treatment of DVT helps prevent this problem.
Post-phlebitic syndrome refers to long-term swelling (edema) in the leg that had the deep vein thrombosis. Changes in skin color and pain can also be present. These symptoms may be noticed right away, or may not develop for one or more years afterward. This problem is called post-thrombotic syndrome.

Prevention

Wear the pressure stockings your doctor prescribed. They will improve blood flow in your legs and reduce your risk for blood clots.
Doctors may prescribe blood thinners to help prevent DVT in people at high risk, or those who are undergoing high-risk surgery.
Moving your legs often during long plane trips, car trips, and other situations in which you are sitting or lying down for long periods of time can also help prevent DVT. People at very high risk for blood clots may need heparin shots when they are on a flight that lasts longer than 4 hours.
Do not smoke. If you smoke, quit. Women who are taking estrogen must stop smoking.


PLEASE NOTE-



Call your doctor if you have symptoms of DVT.
Go to the emergency room  if you have DVT and you develop chest pain, difficulty breathing, coughing blood, fainting, loss of consciousness, or other severe symptoms

Travel Tips

Your risk of developing DVT while traveling is small. The risk increases if the travel time is longer than 4 hours or you have other DVT risk factors.
During long trips, it may help to:

• Walk up and down the aisles of the bus, train, or airplane. If traveling by car, stop about every hour and walk around.
• Move your legs and flex and stretch your feet to encourage blood flow in your calves.
• Wear loose and comfortable clothing.
• Drink plenty of fluids and avoid alcohol.

If you're at increased risk for DVT, your doctor may recommend wearing compression stockings while traveling or taking a blood-thinning medicine before traveling