Pulmonary embolism

A pulmonary embolism is a blockage of an artery in the lungs. It usually occurs when part of a blood clot breaks off and lodges in the lungs. A pulmonary embolism can be life-threatening.

Risk factors

The most common cause of a pulmonary embolism is deep vein thrombosis (DVT). Several factors contribute to the development of DVT. Other conditions that increase the tendency of blood to clot include recent surgery, nonsurgical trauma, previous DVT, a long period of bed rest, cancer, leg paralysis, obesity and use of estrogen or birth control pills.

DVT is more common in people over age 60. Some people have a genetic tendency toward blood clotting.

Symptoms

Symptoms may come on suddenly and may include:

• cough
• shortness of breath
• chest pain 
• rapid breathing
• rapid heart rate

Prevention

If you are at risk for a pulmonary embolism, you can take steps to prevent it by preventing deep vein thrombosis.

• Wear elastic stockings if recommended by your doctor.
• Take medications that prevent blood clots.
• Do leg exercises.