A pulmonary embolism (PE) is a blockage in a blood vessel of the lungs. The blood vessel is an artery that brings fresh blood to the lung tissue. The PE blocks the flow of blood to an area of the lungs. Lung tissue will begin to die without blood flow. The dead tissue will make it difficult for the lungs to work properly. In severe cases, a PE can lead to death.
An embolus is a lump that is floating in the blood. It is usually made of a blood clot. Some can also be made of an air bubble, a piece of fat, bone marrow, or tumor tissue. The embolus travels through the blood until it gets stuck in a smaller blood vessel. This is when it become an embolism. In this case, it is trapped in an artery of the lungs.
A blood clot embolus that lands in the lung often comes from the legs or pelvis.
Factors that may increase your chance of PE include:
Blood clot in a deep vein of a leg or the pelvis
Increased levels of clotting factors in the blood
Prolonged bed rest or sitting, such as during a long trip
Major surgery, especially after pelvic surgery, knee or hip replacement, or heart surgery
Treatment will depend on the size of the clot and how severe your symptoms are. Emergency treatment may be needed.
Emergency treatment may include:
Medicine to dissolve and prevent clots
IV catheter mechanical clot disruption—tube is passed through blood vessels to the clot to break it up or remove it
Medicine may be all that is needed for less severe PEs. The medicine will help to break up the clot and keep new ones from forming.
Thrombolytics are a type of medicine that can dissolve a clot. It is only used in people with a very large PE that is causing severe illness. This type of medicine can cause sudden severe bleeding. It cannot be used in people with a high risk of bleeding.
Anticoagulants (blood thinners) will make it hard for blood to form clots. They will keep the clot from getting bigger and prevent new clots from forming. The body will be able to break up the clot after some time. This option may be used for smaller PEs that are not causing major symptoms. Medicine may need to be taken long term to prevent future blood clots and PEs.
Surgery to remove the clot may be needed if one or more of the following is present:
The blockage is very large
The clot is not responding to initial treatment
The person is in shock
The surgery is called an embolectomy.
A filter will be placed inside a large vein in the abdomen. This filter can catch blood clots that leave the lower body. It will trap the clots before they reach the lungs.
The filter is used for people that have frequent blood clots. It may be needed for people who have not had a good response to other treatment. It may also be an option for those who cannot take blood thinners.
Lowering the risk of blood clots in the legs can decrease the risk of PE.
Break up long periods of sitting. Get up and walk or at least move your legs.
If you are traveling, get up and walk every few hours.
Get out of bed as soon as possible after an illness or surgery.
In addition, people at high risk of developing blood clots should:
Take medicine if your doctor recommends it.
Wear elastic stockings if suggested by your doctor. They can help improve blood flow in your legs.
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