What is a Lung Blood Clot?

Our lungs keep us alive by ridding our bodies of carbon dioxide, a waste product we produce, and exchanging it with oxygen found in the air around us; oxygen is an essential component of many of our bodily functions. The lungs themselves are a pair of organs, each shaped like a pyramid and connected to our windpipes by our right and left bronchi, which themselves branch into smaller bronchioles.

The blood found in our lungs is the substance responsible for facilitating the carbon dioxide and oxygen gas exchange. The pulmonary artery carries shuttles deoxygenated blood to miniscule air sacs called alveoli, which permit rapid gas exchange.

As the pulmonary artery follows our bronchi, it repeatedly branches and becomes smaller. And as the pulmonary arteries branch closer to the alveoli, they turn into the pulmonary capillary network, which is comprised of tiny vessels with thin walls that mirror the alveoli structure and bronchioles.

There are various issues that can arise within our lungs, many of which can be life-threatening conditions. One such condition is called a pulmonary embolism. It’s characterized by being a blockage in one of the pulmonary arteries, and is sometimes called a “lung blood clot.” Pulmonary embolisms are most often caused by blood clots that have traveled from the legs (or other body parts in rare cases) to the lungs. Blockages could, however, on occasion be caused by other substances, such as:

• Air bubbles
• Part of a tumor
• Fat from the marrow of a broken, long bone
• Collagen or another type of tissue

The condition can be life threatening because the clots block the flow of blood to the lungs, but rapid intervention dramatically decreases one’s risk of mortality. According to the Mayo Clinic, you can protect yourself against pulmonary embolisms by preventing clotting in your legs.

There are a variety of risk factors that may increase your risk of developing a pulmonary embolism, such as:

• Prolonged immobility. If you have been on bed rest for a long time, or are taking a long trip in a car or plane, there’s a higher chance you’ll develop blood clots.
• Cancer. Specific cancers (ovarian, lung, pancreatic, or metastasized ones) may increase the levels of substances that aid in blood clotting, as does chemotherapy.
• Heart disease. Heart disease–especially heart failure–increases your likelihood of experiencing the formation of clots.
• Pregnancy. The weight of the baby pressing on pelvic veins during pregnancy may slow the return of blood from the legs, thereby increasing your chance of developing blood clots.
• Smoking. Tobacco use may predispose some individuals to blood clots for reasons that experts don’t yet fully understand; this risk factor is compounded when combined with other ones.
• Being overweight. Excess weight increases your risk of blood clots, especially if you’re a female smoker or have high blood pressure.
• Supplemental estrogen. Individuals who are on hormone replacement therapy or taking birth control pills with estrogen in them may increase the presence of clotting factors in your blood; this is compounded if you are overweight or a smoker.
• Surgery. Medication to prevent blood clots might be given before or after major surgery–like joint replacement–because surgery is one of the major causes of blood clots.

The symptoms associated with a pulmonary embolism can be very different depending on the size of the clot(s), how much of the lung is affected, and whether or not you have an underlying heart or lung issue. Common symptoms include:

• A cough that could also produce bloody sputum.
• Shortness of breath, that often appears suddenly and always worsens with exertion.
• Chest pain that could feel like you’re experiencing a heart attack. The pain worsens with exertion but doesn’t go away if you’re resting.

Other signs could include:

• Fever
• Excessive sweating
• Dizziness or lightheadedness
• A rapid or irregular heartbeat
• Clammy or discolored skin
• Leg pain or swelling (or both), generally in the calf

The Mayo clinic says that you should immediately seek medical attention if you experience inexplicable chest pain, shortness of breath, or a cough that produces bloody sputum.