Pulmonary Embolism
Condition
Definition
A pulmonary embolism (PE) is a blockage in a blood vessel of the lungs. This lowers oxygen levels in the lungs and raises blood pressure in the vessels. It can be deadly in some people.
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Causes
A PE is often caused by a blood clot in the leg or pelvis that travels to the lungs. Less common causes include floating pieces of fat, tumor tissue, or air.
Risk Factors
Having a blood clot in a deep vein of a leg or the pelvis raises the risk of PE. Other things that may raise the risk are:
- Lack of activity due to things like bed rest or a long trip
- Blood clotting disorders
- Recent surgery
- Bone fractures
- Cancer and cancer treatment
- Being overweight or obese
- Smoking
- Recent pregnancy or childbirth
- Some medicines, such as birth control pills and hormone replacement therapy
- Health problems such as stroke, heart disease, and high blood pressure
Symptoms
The symptoms of PE will depend on the size and location of the blockage. The amount of lung tissue that has reduced blood flow will also affect the symptoms. PE may cause:
- Problems breathing, such as shortness of breath and fast breathing
- Chest pain
- Cough, sometimes with bloody phlegm
- Fever
- Feeling faint or lightheaded
- Seizures
Diagnosis
The doctor will ask about symptoms and past health. A physical exam will be done.
Blood tests will be done to look for signs of a clot and to check oxygen levels.
Images may be taken. This may be done with:
- Chest x-ray
- CT scan
- Lung ventilation and perfusion scan
- Pulmonary angiogram
- Ultrasound
- MR angiogram
- Echocardiogram
An electrocardiogram (EKG) may be done to check the electrical activity of the heart.
Treatment
Treatment depends on the size of the clot and the symptoms it is causing. Emergency treatment may be needed.
Prevention
To lower the risk of blood clots that cause PE:
- Break up long periods of sitting. Get up and walk every few hours.
- People who have had a recent illness or surgery should begin to walk as soon as it is safe to do so.
Medicine
Medicine may be given to break up the clot. Blood thinners may be used to make it harder for new clots to form.
American Lung Association
American Society of Hematology
CANADIAN RESOURCES:
Health Canada
The Lung Association
American Lung Association
American Society of Hematology
CANADIAN RESOURCES:
Health Canada
The Lung Association
References
- Machanahalli Balakrishna A, Reddi V, et al. Intermediate-risk pulmonary embolism: a review of contemporary diagnosis, risk stratification and management. Medicina (Kaunas). 2022:1186.
- Pulmonary embolism (PE). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/pulmonary-embolism-pe.
- Pulmonary embolism. Society for Vascular Surgery website. Available at: https://vascular.org/patients-and-referring-physicians/conditions/pulmonary-embolism
- Raja AS, Greenberg JO, et al. Evaluation of Patients with Suspected Acute Pulmonary Embolism: Best Practice Advice from the Clinical Guidelines Committee of the American College of Physicians. Ann Intern Med. 2015 Nov 3;163(9):701-711.
Contributors
- Daniel A. Ostrovsky, MD
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