Preventing Blood Clots

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There are things we can all do to reduce our likelihood of experiencing a dangerous blood clot. For people who are at especially high risk, additional and more specific preventive treatment may be advisable.

Lifestyle Measures

The best way to prevent thrombosis and embolization is to live a healthy lifestyle—the same kind of lifestyle that also reduces your risk of cardiovascular disease and cancer. That's because many lifestyle factors, such as lack of exercise and smoking, are risk factors for blood clots.

With specific regard to preventing blood clots, it is important to:

  • get plenty of exercise.
  • avoid sitting for prolonged periods of time.
  • keep your weight at a healthy level.
  • not smoke.

A Special Word About Smoking

Smoking is terrible for you in many ways, of course. Everyone knows it causes chronic lung disease and cancer. But smoking also causes acute and chronic inflammation in the blood vessels that accelerates atherosclerosis (leading to heart attacks, strokes, and peripheral artery disease)—and that promotes thrombosis.

Smoking particularly elevates the risk of dangerous blood clots in women who are pregnant or taking birth control pills or hormone replacement therapy.

Additional Preventive Measures

Some people, because of their medical conditions or their circumstances, ought to take special measures to reduce their risk of forming blood clots. These people include those who are undergoing prolonged travel, those who are immobilized for a long period of time, those who have a chronically elevated risk of DVT or pulmonary embolus, and those who have a high risk of acute coronary syndrome or stroke.

Prolonged Travel

If you are taking a long trip by airplane or car, your immediate risk of developing DVT increases substantially. To lower that risk, you should make every effort to get up and move around every hour or so. If that turns out to be impossible you can exercise in your seat: stretch your legs, flex your feet, and curl your toes every 15 or 20 minutes. You should also avoid dehydration and avoid wearing tight socks.

Immobilization Due to Hospitalization, Trauma, or Surgery

If you are temporarily immobilized because of trauma, surgery, or hospitalization, you will have an increased risk of DVT.

Since you are under medical care, your doctor should institute preventive measures and give you advice on preventing a blood clot. These measures may include elevating the foot of your bed, doing specific exercises to keep blood moving through your veins, and taking enough pain medication to keep you moving as much as possible. In some cases, a course of anticoagulant medication may be prescribed.

High Risk of DVT or Pulmonary Embolus

Typically, after an episode of DVT or pulmonary embolus, people are treated for several months—or perhaps up to a year—with an anticoagulant drug. Some people, however, are thought to have a greatly elevated chronic risk of recurrent thrombosis and may require permanent anticoagulation therapy. People in this category include those with:

  • DVT or pulmonary embolus that is already recurrent.
  • DVT or pulmonary embolus that was not produced by an identifiable cause (and is therefore likely to come back for “no reason”).
  • active cancer.
  • genetic propensity to excess blood clotting.

Atrial Fibrillation

People with chronic or recurrent atrial fibrillation have a high risk of developing blood clots in the left atrium of the heart. These clots can break off and produce stroke. People with atrial fibrillation that is not merely transient should be treated with chronic anticoagulation therapy.

High Risk of Acute Coronary Syndrome or Stroke

People who are at high risk of having an episode of acute coronary syndrome (a condition that causes heart attacks and unstable angina) should be placed on anti-platelet drugs (such as aspirin or Plavix) to reduce the risk of clot formation in case of a rupture of an atherosclerotic plaque. Anti-platelet drugs are also used to prevent thrombosis after a stent is placed in a coronary artery.

Anti-platelet drugs are also commonly used to reduce the risk of subsequent strokes in people who have had a thrombotic stroke.

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