What to Know About Pulmonary Embolism

Pulmonary embolism (PE) is when blood flow to the lungs is blocked. This can result in damage to the parts of the lungs that do not get enough blood flow. PE can make it harder for the lungs to take in enough oxygen. This lack of oxygen can also damage other organs. PE is a serious condition that requires emergency treatment.^1-3

What causes pulmonary embolism?

In most cases, deep vein thrombosis (DVT) leads to PE. DVT is a clot that forms in a vein deep within the body. Most commonly, the clot forms in the legs. DVT can lead to PE if the clot breaks off and blocks the blood flow to the lungs.^1-3

Normally, blood clots form to stop bleeding after an injury. But these clots can sometimes form inside a blood vessel. When a blood clot forms inside a vein or artery, it can block blood flow. Often, the clot forms in one part of the body and then travels with the blood until it gets stuck within the artery or vein. In PE, the blood clot stops blood flow in one of the main arteries that provides blood to the lungs.^1,4

Things other than a blood clot – like an air bubble, tumor, or fat – can also block blood flow and lead to PE.^1-3

Who is at a higher risk for pulmonary embolism?

Anyone can develop blood clots or DVT. But certain factors can increase a person’s chances of forming a blood clot, including:^2-4

• Older age
• Obesity
• Smoking
• Pregnancy and childbirth
• Hormone medications such as birth control pills and hormone replacement therapy (HRT)
• Genetics, or a family history of blood clots

Having certain diseases also can make it more likely for blood clots to form. For example, people with peripheral artery disease (PAD) are more likely to develop blood clots. PAD causes a buildup of plaque in the arteries, which narrows the arteries and makes it easier for blood clots to form.⁵

Other diseases and conditions that increase the chance of developing a blood clot include:^3,4

• Cancer
• Heart disease
• Lung disease
• Stroke
• Clotting disorders
• Spinal cord injury
• Joint replacement surgery

Temporary factors that can increase risk include prolonged lack of movement, such as a long car ride or recovery from surgery. Dehydration also can raise the risk of blood clots.^2,3

What are the symptoms of pulmonary embolism?

The symptoms of PE can be different for different people. The most common symptoms include:⁴

• Shortness of breath
• Chest pain
• Coughing up blood

People may also experience symptoms related to DVT, usually in the legs. These include:⁶

• Swelling
• Pain
• Tenderness

In more serious cases, PE can lead to:^3-6

• Fainting
• Dizziness
• Irregular heartbeat
• Shock, from not enough blood flow in the body
• Pulmonary hypertension – The blood clot increases the blood pressure in the lungs. This causes the heart to work harder, which can weaken the heart.

How to prevent pulmonary embolism

There are certain things you can do to lower your chances of developing PE. These preventative measures include:⁴

• Quit smoking
• Avoid staying still for long periods
• Stay hydrated
• Raise your legs by placing them on a pillow when sleeping
• Maintain a healthy body weight
• Exercise regularly

Your doctor may prescribe drugs to prevent or treat PE. These may be:^4,6

• Statins – These drugs can reduce the buildup of plaque in the arteries.
• Blood thinners – These drugs reduce the chances of developing blood clots by thinning out the blood.

PE is a serious medical condition. If you experience any symptoms of PE, seek medical help immediately. Treatments are available that can restore blood flow to the lungs and reduce further complications.^2,3