Definition of Pulmonary edema:

Pulmonary edema is an abnormal build up of fluid in the lungs, which leads to swelling.

Causes, incidence, and risk factors:

Pulmonary edema is usually caused by heart failure. As the heart fails, pressure in the veins going through the lungs starts to rise. As the pressure in these blood vessels increases, fluid is pushed into the air spaces (alveoli) in the lungs. This fluid interrupts normal oxygen movement through the lungs, resulting in shortness of breath.

Pulmonary edema may be caused by damage directly to the lung, such as that caused by poisonous gas or severe infection. Lung damage with a buildup of body fluid is also seen in kidney failure.

Pulmonary edema may also be a complication of a heart attack, leaking or narrowed heart valves (mitral or aortic valves), or any disease of the heart that results in weakening or stiffening of the heart muscle (cardiomyopathy).