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

• Lung damage caused by poisonous gas or severe infection

• Certain medications

• Major injury

• Kidney failure

• Exercising at very high altitudes

Pulmonary edema may also be due to

• Heart attack

• Leaking or narrowed heart valves (mitral or aortic valves)

• Any disease of the heart that results in weakening or stiffening of the heart muscle (cardiomyopathy)

Symptoms

Symptoms of pulmonary edema may include:

• Coughing up blood or bloody froth

• Difficulty breathing when lying down (orthopnea) -- you may need to sleep with your head propped up or use extra pillows

• Feeling of "air hunger" or "drowning" (if this occurs suddenly, awakening you from sleep and causing you to sit up and catch your breath, it's called "paroxysmal nocturnal dyspnea")

• Grunting, gurgling or wheezing sounds with breathing

• Inability to speak in full sentences because of shortness of breath

Other symptoms may include:

• Anxiety or restlessness

• Leg swelling

• Excess sweating

• Pale skin

• Decrease in level of alertness (consciousness)

Signs and tests

The health care provider will perform a physical exam and use a stethoscope to listen to the lungs and heart. The following may be detected:

• Crackles in the lungs, called rales

• Abnormal heart sounds

• Increased heart rate (tachycardia)

• Pale or blue skin color (pallor or cyanosis)

• Rapid breathing (tachypnea)

Possible tests include:

• Complete blood count (CBC)

• Blood chemistries

• Kidney function blood tests

• Blood oxygen levels (oximetry or arterial blood gases)

• Chest x-ray

• Electrocardiogram (ECG) to look for signs of a heart attack or problems with the heart beat

• Ultrasound of the heart (echocardiogram) to see if there is a weak heart muscle, leaky or narrow heart valves, or fluid surrounding the heart

Treatment

Pulmonary edema is most always treated in the emergency room or hospital intensive care unit (ICU).

• Oxygen is given through a face mask or tiny plastic tubes placed in the nose.

• A breathing tube may be placed into the windpipe (trachea).

• A breathing machine (ventilator) may be needed.

The cause of the edema should be rapidly identified and treated. For example, if a heart attack has caused the condition, it must be treated.

Medications that may be prescribed include:

• Diuretics, which remove excess fluids from the body

• Medicines to strengthen the heart muscle, control the heart beat, or relieve pressure on the heart

Expectations (prognosis)

Outlook depends on the cause. The condition may resolve quickly or slowly. Some patients may need to use a breathing machine for a long time. If not treated, this condition can be deadly.

Calling your health care provider

Go to the emergency room or call 911 if you have breathing problems.

Prevention

If you have a disease that can lead to pulmonary edema or a weakened heart muscle, take all prescription medications as instructed. Following a healthy diet, one low in salt and fat, can significantly reduce the risk of developing this condition.