Pulmonary edema is best described as which of the following?

Pulmonary edema is best described as which of the following?

• A. Abnormal accumulation of fluid in the interstitial spaces, alveoli, or cells of the lungs that inhibits gas exchange
• B. Excess fluid in the pleural space outside the lungs
• C. Inflammation of the pleura surrounding the lungs
• D. Collapse of alveoli due to lack of air

Answer: (A)

Pulmonary edema means fluid has abnormally accumulated in the lungs, specifically in the interstitial tissues and the alveolar spaces, which directly impairs gas exchange. When fluid fills the interstitium and alveoli, the diffusion distance for oxygen increases and the ventilation–perfusion balance is disrupted, leading to hypoxemia and breathlessness. The presence of fluid in the airspaces also reduces lung compliance, making breathing harder and often producing crackles on auscultation and, in severe cases, pink-tinged frothy sputum. This description fits pulmonary edema, whereas fluid in the pleural space (pleural effusion), inflammation of the pleura (pleuritis), or collapse of alveoli from lack of air (atelectasis) involve different parts of the chest or different mechanisms.

Pulmonary edema means fluid has abnormally accumulated in the lungs, specifically in the interstitial tissues and the alveolar spaces, which directly impairs gas exchange. When fluid fills the interstitium and alveoli, the diffusion distance for oxygen increases and the ventilation–perfusion balance is disrupted, leading to hypoxemia and breathlessness. The presence of fluid in the airspaces also reduces lung compliance, making breathing harder and often producing crackles on auscultation and, in severe cases, pink-tinged frothy sputum. This description fits pulmonary edema, whereas fluid in the pleural space (pleural effusion), inflammation of the pleura (pleuritis), or collapse of alveoli from lack of air (atelectasis) involve different parts of the chest or different mechanisms.