Pulmonary Embolism

5 min read

What is a pulmonary embolism?

A pulmonary embolism is a blockage in the blood vessel that carries blood to your lungs (pulmonary artery). It is usually caused by a blood clot that has broken free from somewhere in your body (typically the legs) and travelled to your lungs. It can be life-threatening if it is not treated immediately.

What does it feel like when you have a pulmonary embolism?

A pulmonary embolism may not cause any symptoms, especially if it is a small embolism. However, when symptoms occur, they include:

  • shortness of breath - this may be mild or severe
  • sharp pain in your chest or upper back when you breathe in
  • coughing up blood
  • feeling faint or unwell
  • fever

Because the blood clot that causes a pulmonary embolism often comes from the leg (a

), you may also have symptoms of a DVT, such as calf pain, redness, tenderness, warmth and swelling. Your foot may also be swollen.

What causes pulmonary embolism?

A pulmonary embolism happens when an artery in your lungs gets blocked by a blood clot. In most cases, a blood clot forms in the deep veins in your legs (a condition known as

deep vein thrombosis or DVT
), breaks free, and travels up to your lungs.

Certain factors can increase the likelihood of a pulmonary embolism. These include:

  • previous damage to the walls of blood vessels - this includes previous DVT and surgery
  • poor blood flow in the body - this can be caused by anything that stops you from being mobile e.g. stroke and spinal cord injury
  • blood that clots more easily than normal - this can also be caused by many things, including pregnancy, obesity and genetic conditions

How do you stop a blood clot from forming?

To lower your risk of developing a blood clot, it can help to:

  • get regular exercise, including gentle exercise like walking
  • drink lots of fluids to prevent dehydration
  • try to lose weight if you are overweight

If you are going to be sitting for a long period of time - like on a long-haul flight - it can help to wear flight socks or stockings. These can help improve your blood flow. You should also try to stand up and move around every 30 minutes.

Speak to your local pharmacist for advice on using flight socks when flying.

Is it safe to exercise with a blood clot?

Once you’re receiving anticoagulant medication for a pulmonary embolism, you can return to the same level of physical activity as you used to do before you developed a pulmonary embolism, but exercise should be gradually reached within six weeks.

You may have some breathlessness or occasional sharp chest pain while exercising, but this is normal and will improve with time.

What should I eat after a pulmonary embolism?

If you have had a pulmonary embolism, you will likely be prescribed an anticoagulant (blood thinning) medicine called warfarin for at least three months. Some foods and drinks can affect how well warfarin works, so you may need to:

  • keep your diet consistent
  • avoid drinking more than one or two alcoholic drinks a day and never binge drink
  • avoid taking herbal medicines
  • avoid drinking cranberry juice

Speak to your doctor for more specific advice on what you should eat after a pulmonary embolism.

How do you treat a pulmonary embolism?

A pulmonary embolism is usually treated with anticoagulant injections and/or medicines (sometimes called blood thinners) and oxygen. In some cases, more invasive treatment might be necessary to remove the clot, such as treating the clot through a fine tube (catheter) or surgery.

Oxygen is usually given in the early stages of treatment to help improve breathlessness and low blood oxygen levels. Anticoagulants help to stop any blood clots you may have from getting bigger and prevent new ones from forming.

You may need to have anticoagulant injections (heparin or low-molecular weight heparin) for at least five days. Once blood tests show that the injections are breaking down the clots in your body, you will likely be given anticoagulant tablets (warfarin is the most common, but others exist) instead of injections.

Your doctor will advise you on how long you need to take anticoagulants for. If you are pregnant, you may be given regular heparin injections instead of warfarin because warfarin can harm an unborn child. If you have cancer, you may also be given heparin injections instead or warfarin, as warfarin isn’t always effective in people with cancer.

How do you diagnose a pulmonary embolism?

Your doctor may suspect a pulmonary embolism based on your symptoms and medical history. Additional tests may be used to help confirm the diagnosis. These include:

  • blood tests - for a substance (d-dimer) that indicates a blood clot, to check blood oxygen levels, to check how well your blood clots, and to look for signs of a heart attack, infection, or inflammation
  • an ECG scan
  • an ultrasound scan of the leg (doppler) to find the source
  • a CT scan of the lung arteries (CTPA)
  • a ventilation-perfusion scan to examine the flow of air and blood in your lungs
  • a chest X-ray

Can a person survive a pulmonary embolism?

Yes. If a pulmonary embolism is spotted and treated early, most people can make a full recovery.

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.