Pulmonary Embolism

What is Pulmonary Embolism?

The lungs are responsible for the process of exchanging carbon dioxide in our blood for oxygen. This oxygen is derived from the air we breathe. The exchange of air between the blood in the body and the lungs takes place in our arteries and veins. Arteries are responsible for carrying (oxygenated) blood from the heart to the rest of the body whereas veins carry (deoxygenated) blood from the body to the heart. This deoxygenated blood rich in carbon dioxide is then pumped from the heart to the lungs where it receives fresh oxygen and is returned to the heart to be sent to various parts of the body once again. This entire process is referred to as the process of circulation.

Sometimes, a blood clot or thrombus may form in one of the veins. This clot can travel through the circulatory system towards the heart and ultimately become lodged in one of the branches of the pulmonary artery within the lungs. This clot is known as a pulmonary embolus (In case it travels and gets lodged in another part of the body it is referred to as plural embolus).

A pulmonary embolus clogs the artery and prevents the exchange of carbon dioxide for oxygen. Additionally, it damages lung tissue as it decreases the overall blood supply to the lungs.

Alternative Names: Venous thromboembolism (VTE), PE.

Types: There are two different types of pulmonary embolism which have been identified:

  • Acute pulmonary embolism occurs if the embolus occurs within the vascular lumen
  • Chronic pulmonary embolism occurs when an embolus is contiguous within the walls of the blood vessel