What describes an air embolism?

An air embolism is characterized by the presence of air bubbles that enter the circulatory system, which can occur through various means, most notably through intravenous (IV) lines or as a result of chest trauma. This condition can lead to serious complications, such as obstruction of blood vessels, which may result in ischemia or damage to vital organs.

The correct choice highlights that room air can inadvertently enter the circulation, particularly in medical settings where IV therapy is employed. This can happen if there is a break in the integrity of the IV line or during procedures where air might be introduced into blood vessels.

In contrast, the other options refer to different medical conditions: clots formed in deep veins relate to deep vein thrombosis, fluid accumulation in the lungs pertains to pulmonary edema, and the presence of fat globules in the bloodstream is indicative of fat embolism, which has distinct causes and clinical implications. Thus, the choice that correctly defines an air embolism focuses specifically on the entry of air into the circulatory system, which aligns with established medical definitions and understanding.