Final answer:
A pulmonary embolism (PE) is a life-threatening condition caused by a blood clot that blocks blood flow in the pulmonary arteries, leading to impaired gas exchange and potentially fatal consequences.
Step-by-step explanation:
A pulmonary embolism (PE) occurs when a blood clot breaks loose and travels through the bloodstream to the pulmonary arteries. These arteries carry deoxygenated blood from the heart to the lungs. In lungs, this blood should normally pick up oxygen and release carbon dioxide. However, if a clot lodges in these vessels, it can severely obstruct the blood flow, leading to potentially life-threatening consequences such as lung damage or even sudden death.
When this clot, or embolus, becomes trapped, it is called an embolism, and it can block a vessel critical to a major organ like the heart, brain, or lungs. As an embolism in the lungs could result in a pulmonary embolism, this is considered a medical emergency and requires immediate attention. Some symptoms of PE may include shortness of breath, chest pain (as seen in conditions like pulmonary edema), coughing, and in severe cases, hypo-tension leading to shock.
PEs are serious medical conditions that affect the gas exchange process in the alveoli by compromising pulmonary circulation, and in chronic cases, can resemble symptoms similar to chronic obstructive pulmonary disease (COPD), with persistent airflow limitation and phlegm production.