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Pulmonary Embolism

Pulmonary embolism happens when one or more of your arteries in your lungs gets blocked by a blood clot, fat or tumour. The most common type of pulmonary embolism is caused by a blood clot that moves through your blood stream, goes through your heart and blocks off an artery in your lung.

Most pulmonary embolisms are caused from clots originating in the lower extremities (deep vein thrombosis), and many resolve on their own. However in some cases, pulmonary embolism can cause sudden death.

Pulmonary embolism can be caused by:

  • Clots from the venous circulation from the right side of the heart or tumours that have invaded the circulatory system
  • Other sources such as amniotic fluid, air, fat, bone marrow and foreign substances

Early detection and treatment of deep vein thrombosis (clots of the legs) can reduce the risk of pulmonary embolism.

To reduce your risk after surgery, your healthcare provider may encourage you to walk and start some activity.  Other ways to prevent clotting may include leg exercises and compression stockings. As well, low doses of heparin injected under the skin (subcutaneous heparin therapy) may be used for people who have to stay in bed for a long time.

Prevention while traveling

The risk of getting a blood clot while you travel is low. However, anyone traveling more than four hours, whether by air, car, bus, or train, may be at risk for blood clots. While you travel move your legs frequently and exercise your calf muscles. When possible take a break from sitting to stretch your legs. Some airlines will have exercises you can do in the magazine in your seat pocket.

Anyone can get a pulmonary embolism. The risk factors are:

  • prolonged bed rest or inactivity, including a long trip in a car or in a plane
  • using oral contraceptives (birth control pills)
  • surgery
  • pregnancy – before, during and after delivery
  • cancer
  • stroke
  • heart attack
  • heart surgery
  • fractures of the hips or femur
  • previous deep vein thrombosis

People with pulmonary embolus may have:

  • a cough that begins suddenly, and may produce bloody sputum (mucus), significant amounts of visible blood or lightly blood streaked sputum (phlegm)
  • sudden onset of shortness of breath at rest or with exertion
  • lightheadedness
  • fainting
  • dizziness
  • sweating
  • anxiety
  • rapid breathing
  • rapid heart rate
  • chest pain:
    • under the breastbone or on one side
    • sharp, stabbing, burning, aching or dull, heavy sensation
    • may be worse at night
    • may radiate to the shoulder, arm, neck, jaw, or other area
    • may be worsened by breathing deeply, coughing, eating, bending or stooping

If you have any of these symptoms, or if you think you have a pulmonary embolism, see your healthcare provider right away. Your healthcare provider can determine if your symptoms are caused by a pulmonary embolism or by another disease.

If you think you have a pulmonary embolism it is important to get medical treatment right away.

If your healthcare provider diagnosed a blood clot in your lung (or leg) you will be treated with an anticoagulation therapy (blood clot prevention medication) called warfarin and heparin.  It is important to talk to your healthcare provider and pharmacist about all of the possible side effects with anticoagulation therapy.

Your healthcare provider may also prescribe clot dissolvers (thrombolytics). Most clots usually dissolve on their own but sometimes you may get medicines to help the clots dissolve quickly. There are a number of risks with these drugs and are often only giving in emergency situations.