July 6, 2009

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Pulmonary Embolism

Pulmonary Embolism Overview

A pulmonary embolism (PE) is a blood clot in the lung. It usually comes from smaller vessels in the leg, pelvis, arms, or heart. When a clot forms in the legs or arms, it is referred to as a deep venous thrombosis (DVT).

The clot travels through the vessels of the lung continuing to reach smaller vessels until it becomes wedged in a vessel that is too small to allow it to continue farther. The clot gets wedged and prevents any further blood from traveling to that section of the lung.

When no blood reaches a section of the lung, that portion of the lung suffers an infarct, meaning it dies because no blood or oxygen is reaching it. This is referred to as a pulmonary (or lung) infarct.

Pulmonary Embolism Causes

Several factors can make someone more likely to develop a blood clot that can eventually break loose and travel to the lung.

  • Immobilization: A stroke, broken bone, or spinal cord injury can result in confinement to bed so that clot formation can occur in either the arms or legs.

  • Travel: Prolonged travel, such as sitting in an airplane or a long car trip, allows the blood to sit in the legs and increases the risk of clot formation.

  • Recent surgery

  • Trauma or injury (especially to the legs)

  • Obesity

  • Heart disease (such as an irregular heartbeat)

  • Burns

  • Previous history of blood clot in the legs (DVT) or PE

  • Conditions that increase clotting of the blood



Next: Pulmonary Embolism Symptoms »

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Pulmonary Embolism »

Pulmonary embolism (PE) is a common and potentially lethal disease; unfortunately, the diagnosis is often missed because patients with PE present with nonspecific signs and symptoms.

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