A pulmonary embolism (PE) is a blood clot that develops in a blood vessel in the body (often in the leg). It then travels to a lung artery where it suddenly blocks blood flow.
A blood clot that forms in a blood vessel in one area of the body, breaks off, and travels to another area of the body in the blood is called an embolus. An embolus can lodge itself in a blood vessel. This can block the blood supply to a particular organ. This blockage of a blood vessel by an embolus is called an embolism.
The heart, arteries, capillaries, and veins make up the body's circulatory system. Blood is pumped with great force from the heart into the arteries. From there blood flows into the capillaries (tiny blood vessels in the tissues). Blood returns to the heart through the veins. As it moves through the veins back to the heart, blood flow slows. Sometimes this slower blood flow may lead to clot formation.
Blood clotting is a normal process to prevent bleeding. The body makes blood clots and then breaks them down. Under certain circumstances, the body may be unable to break down a clot. This may result in a serious health problem.
When blood clots in a vein, it may be due to the slowed blood flow, an abnormality in clot forming, or from an injury to the blood vessel wall.
Blood clots can form in arteries and veins. Clots formed in veins are called venous clots. Veins of the legs can be superficial veins (close to the surface of the skin) or deep veins (located near the bone and surrounded by muscle).
Venous clots most often happen in the deep veins of the legs. This is called deep vein thrombosis (DVT). Once a clot has formed in the deep veins of the leg, there is a potential for part of the clot to break off and travel through the blood to another area of the body, often the lung. DVT is the most common cause of a pulmonary embolism.
Other less frequent sources of pulmonary embolism are a fat embolus (often linked to the breaking of a large bone), amniotic fluid embolus, air bubbles, and a deep vein thrombosis in the upper body. Clots may also form on the end of an indwelling intravenous (IV) catheter, break off, and travel to the lungs.
Risk factors for pulmonary embolism include:
The following are the most common symptoms for pulmonary embolism (PE). However, each person may experience symptoms differently:
You may also have symptoms of deep vein thrombosis (DVT), such as:
If your healthcare provider thinks you have a PE, he or she will check your legs for signs of deep vein thrombosis.
The type and extent of symptoms of a PE will depend on the size of the embolism and whether you have heart and/or lung problems.
The symptoms of a PE may look like other medical conditions or problems. Always talk with a healthcare provider for a diagnosis.
Pulmonary embolism (PE) is often difficult to diagnose because the symptoms of PE are a lot like those of many other conditions and diseases.
Along with a complete medical history and physical exam, tests used to look for a PE may include:
Treatment choices for pulmonary embolism (PE) include:
An important aspect of treating a PE is preventive treatment to prevent formation of additional embolisms.
A pulmonary embolism (PE) can cause a lack of blood flow that leads to lung tissue damage. It can cause low blood oxygen levels that can damage other organs in the body, too.
A PE, particularly a large PE or many clots, can quickly cause serious life-threatening problems and, even death.
Treatment of a PE often involves anti-coagulation medicines or blood thinners. These medicines can put you at a risk for excessive bleeding if they thin your blood too much. Excessive bleeding is bleeding that won't stop after you apply pressure for 10 minutes. Other symptoms of bleeding to watch for include:
Signs of bleeding in the digestive system:
Signs of bleeding in the brain:
If you have any of these, you need to get treatment right away.
Treatment to prevent DVTs includes:
Ways to prevent DVT without medicine include:
Anticoagulants and aspirin are often given to help prevent DVT.
Many people remain at risk for developing DVTs for a period after they are either discharged from the hospital. It is important that treatment to prevent DVTs continue until the risk has been resolved, usually about 3 to 6 months.