Pulmonary Edema

Pulmonary edema is a condition caused by excessive fluid accumulation in the lungs. This fluid collects in many of the alveoli in the lungs and causes difficulty breathing.

In most cases, pulmonary edema is due to a heart problem. However, other causes can also cause fluid to collect in the lungs. These include pneumonia, exposure to certain toxins, medications, chest wall trauma, and travel or exercise at high altitudes.

Sudden onset of pulmonary edema (acute pulmonary edema) is a medical emergency that requires immediate treatment. Pulmonary edema can sometimes lead to death. Prompt treatment may be helpful. Treatment of pulmonary edema depends on the cause and usually includes supplemental oxygen and medication.

Symptoms
Pulmonary edema symptoms may come on suddenly or progress over time. Specific symptoms depend on the type of pulmonary edema.

Sudden (acute) pulmonary edema symptoms
Dyspnea or extreme shortness of breath that worsens with activity or lying down
Choking or drowning sensation is more pronounced when lying down
Foamy sputum, possibly with blood, when coughing
Rapid, irregular heartbeat (palpitations)
Anxiety, restlessness or feeling that something bad is about to happen
Wet and cold skin
Croup or shortness of breath when breathing
Signs and symptoms of long-term (chronic) pulmonary edema
Waking up at night with a cough or feeling short of breath; getting up and sitting may relieve these symptoms
Feeling breathless when moving or lying down
Fatigue
Shortness of breath more than usual during physical activity
New or worsening cough
Rapid weight gain
Swelling of the legs and feet
Croup
Signs and Symptoms of High Altitude Pulmonary Edema (HAPE)
HAPE may occur in adults and children who travel to or exercise at high altitudes. Symptoms are similar to those of acute pulmonary edema and may include

Headache, which may be the initial symptom
Shortness of breath during activity, which may evolve into shortness of breath at rest
Inability to exercise at the same level as before
Dry cough, which is the initial symptom
Later in life, cough with pink or bloody foamy sputum
Extremely rapid heartbeat (tachycardia)
Weakness
Pain in the chest
Low fever
Symptoms of high altitude pulmonary edema (HAPE) tend to get worse at night.

When to seek medical attention
Sudden onset pulmonary edema (acute pulmonary edema) can be life-threatening. Seek emergency medical attention if you experience any of the following acute symptoms:

Shortness of breath, especially sudden shortness of breath
Difficulty breathing or feeling suffocated (dyspnea)
Bubbling, growling or wheezing sounds when you breathe
Coughing up pink or bloody sputum
Difficulty breathing and profuse sweating
Bluish or grayish skin
Delirium of consciousness
Significant drop in blood pressure, resulting in light-headedness, dizziness, weakness, or sweating
Sudden worsening of any pulmonary edema symptoms

Causes
The causes of pulmonary edema vary. Depending on the cause, pulmonary edema can be divided into two categories.

If the pulmonary edema is caused by a heart problem, it is called cardiogenic pulmonary edema. In most cases, fluid accumulation in the lungs is due to a heart condition.
If the pulmonary edema is not related to the heart, it is called non-cardiogenic pulmonary edema.
Sometimes, pulmonary edema is caused by a combination of cardiac and non-cardiac problems.
Understanding the relationship between the lungs and the heart helps to understand why pulmonary edema occurs.

How the lungs work
The lungs have many small, flexible air sacs called "alveoli. Each time you breathe, these air sacs breathe in oxygen and release carbon dioxide. Normally, there is nothing wrong with this gas exchange phenomenon.

Sometimes, however, fluid enters the alveoli instead of air. This prevents the bloodstream from drawing in oxygen.

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