Pulmonary Edema

Fluid can build up in the lungs for many reasons, making it difficult for the lungs to give oxygen to the blood. Symptoms result both from the fluid and from the resulting low oxygen level in the blood.

Pulmonary edema may cause:

• shortness of breath, which usually gets worse with activity or when laying flat
• coughing up frothy phlegm, which may contain some blood
• a fast heartbeat, known as tachycardia
• anxiety
• excessive sweating

A person may also have symptoms from the underlying cause of the pulmonary edema.

Pulmonary edema has many causes, including:

• heart disease, such as congestive heart failure, a weakened heart due to cardiomyopathy or heart attacks. An abnormal condition of a heart valve, such as chronic mitral regurgitation, may also cause pulmonary edema.
• infection in the lung, such as pneumonia
• infection in the blood, known as sepsis
• low protein levels in the body, such as from malnutrition or a kidney condition called nephrotic syndrome, in which protein is lost into the urine. Cirrhosis, or permanent hardening and scarring of the liver, can also cause low protein in the body.
• exposure to certain toxins or medications, such as carbon monoxide poisoning or a severe aspirin overdose
• a severe allergic reaction, called anaphylaxis, which may occur in response to antibiotics such as penicillin and other medications
• acute mountain sickness, which occurs when a person goes from a low altitude to a high altitude quickly
• narcotic overdose
• radiation therapy or radiation sickness

Many cases of pulmonary edema are unavoidable. Persons with heart problems should take medications as prescribed. A person should not abuse narcotics. Those who are mountain climbing should avoid be alert to symptoms of mountain sickness and not climb beyond the limits of their training.

A healthcare professional will usually suspect pulmonary edema from the history and physical findings. The fluid in the lungs shows up as whited-out lung fields on the chest x-ray, confirming the diagnosis. In some cases, further tests may be needed to figure out the cause of the lung edema. These may include blood tests or pulmonary ventilation and perfusion scans.

Severe pulmonary edema can lead to death from lack of oxygen. Most of the long-term effects, however, are related to the underlying cause of the pulmonary edema. For example, those with severe heart disease may be unable to perform daily activities without getting tired or having shortness of breath. On the other hand, edema from an infection that is successfully treated often causes no long-term effects.

Lung edema is not contagious and does not pose any risk to others.

A person with lung edema usually needs to breathe supplemental oxygen through nasal tubes or a mask. If the edema is severe, the person may need to be put on a ventilator, or artificial breathing machine.

Other treatments depend on the underlying cause. For example, diuretic medications, or "fluid pills," may be given to draw fluid out of the lungs. Antibiotics are given if a bacterial infection is the cause.

Persons who require a ventilator may rarely develop an infection or damage to the lungs from the machine. All medications can have side effects. Diuretics may cause allergic reactions and salt imbalances. Antibiotics also may cause allergic reactions or stomach upset..

If the underlying cause of the pulmonary edema is corrected, the person gets better and can return to normal activities. Lifelong treatment may be needed to prevent future episodes of pulmonary edema, such as in a person with a weakened heart.

Symptoms are monitored and follow-up physical exams are needed. Blood tests, the amount of urine produced, and chest x-rays may also be used for monitoring.