Pulmonary embolism is a medical condition in which the arteries (the large blood vessels) in the lungs are blocked by a blood clot, an air bubble or by fat. The most common cause is a blood clot traveling from the legs to the lungs, and there are multiple possible causes for this. The most common symptoms are shortness of breath and a chest pain which is gets worse when taking deep breaths. Treatment includes removing the blockage, which is often done with blood-thinning medications which dissolve the blood clot. If the person is diagnosed and treated quickly, the outcome after pulmonary embolism is good.
A embolus is an object which is not dissolved in the blood and which travels through the blood vessels. These tend to travel until the blood vessels become too small for it to travel further. This blocks the blood vessel, which may cause the tissues at the end of the blood vessels to become starved of oxygen and nutrients. A pulmonary embolus the medical term for when this occurs in the lungs. It most commonly occurs as a result of a blood clot which starts in the legs and travels to the lungs, but there are several less common causes, such as a big air bubble in the blood, or fat entering the bloodstream. This condition is common, and tends to affect older adults more commonly than younger people. Things which encourage blood clots to form in the legs increase the risk of this condition. This includes smoking, prolonged periods of sitting or lying and certain medical conditions, especially cancer, vasculitis, and conditions which cause the blood to clot easily (antiphospholipid syndrome). People who have recently had a major surgery are also at increased risk of this condition. Pregnant women and women who take the birth control pill have a higher risk of developing a pulmonary embolism.
The typical symptoms of a pulmonary embolus are shortness of breath and a chest pain which gets worse when taking deep breaths. Other symptoms may include a cough, dizziness, a blue tinge to the skin and a loss of consciousness. People who have a blood clot in the leg may also have redness and swelling of the leg with the clot.
A pulmonary embolus may be suspected based on the symptoms and physical examination, but further tests are usually needed to confirm the diagnosis. This may include blood tests and scans of the chest and lungs.
A pulmonary embolism is often medical emergency. Treatment involves making sure that the affected person is stable, removing the cause, and taking steps to prevent future clots. If the cause is a blood clot, this requires medications to thin the blood and dissolve the clot. Other causes may require emergency surgery, but this is rare. People who are at risk of future blood clots and pulmonary embolus may need to take long-term blood thinning medications. If this is not an option, placing a filter in the big blood vessel that goes from the legs to the heart and lungs helps to prevent future clots. This is called an inferior vena cave (the big blood vessel) filter.
Taking steps to prevent blood clots in the legs, especially in people who are known to be at risk, can help to avoid pulmonary embolism. This may involve wearing stockings that help blood flow, or avoiding long periods of lying or sitting.