Final answer:
Pulmonary edema is excess fluid in the air sacs of the lungs, often caused by heart or kidney failure. It can be life threatening due to compromised gas exchange. Seek immediate medical care if symptoms occur.
Step-by-step explanation:
Pulmonary edema is excess fluid in the air sacs of the lungs, a common symptom of heart and/or kidney failure. It occurs when fluids get "backed up" in the pulmonary capillaries, leading to leakage of water into the interstitial spaces of the lungs. The increased fluid in the interstitial spaces compromises gas exchange and can be life threatening. Immediate medical care should be sought if symptoms like difficulty breathing and chest pain are experienced.