Pulmonary edema, or acute lung edema, is a build-up of water in the lungs. There are two forms, the most common being cardiogenic pulmonary edema. It is a cardiovascular complication that particularly affects the elderly. Pulmonary edema can lead to respiratory failure and be life threatening. Appropriate and rapid support is essential.

Definition of pulmonary edema

Pulmonary edema is a pathology that affects the respiratory system. It is characterized by an accumulation of fluid in the pulmonary extravascular tissues and spaces. The liquid can seep into the alveoli, which can lead to a state of respiratory distress.

Types of pulmonary edema

It is possible to distinguish two types of pulmonary edema:

• cardiogenic pulmonary edema, the most frequent, which is the consequence of an increase in hydrostatic pressure in the pulmonary capillaries;
• non-cardiogenic pulmonary edema which is the consequence of an alteration in the permeability of the pulmonary capillaries and which essentially constitutes lesional pulmonary edema, that is to say due to an injury / attack on the organism.

Causes of pulmonary edema

Several possible causes have been identified. With regard to cardiogenic pulmonary edema, it is often linked to left ventricular failure. This can be the consequence of several cardiovascular disorders including:

• a myocardial infarction;
• dilated cardiomyopathy;
• mitral or aortic valve disease;
• arrhythmia.

In non-cardiogenic pulmonary edema, it is caused by the activation of inflammatory mediators in response to:

• direct injury such as lung infection, smoke inhalation, chest trauma, extensive pneumonitis or drowning;
• indirect aggression such as sepsis or pancreatitis.

Diagnosis of pulmonary edema

Pulmonary edema is a medical emergency. Its diagnosis is mainly based on the evaluation of perceived symptoms and the clinical examination.

In some cases, additional examinations may be performed. This is usually a chest x-ray and a blood test. 

People affected by pulmonary edema

Cardiogenic pulmonary edema mainly affects adults, and particularly the elderly. Non-cardiogenic pulmonary edema can affect anyone.

Factors promoting pulmonary edema

Certain factors have been shown to promote pulmonary edema. Among them are in particular:

• malnutrition ;
• cirrhosis;
• nephrotic syndrome, kidney disease.

The first symptoms are usually:

• dyspnea, a feeling of respiratory discomfort;
• restlessness;
• anxiety;
• a feeling of suffocation;
• a cough ;
• pallor;
• a cyanose;
• sweating.

Pulmonary edema can also be manifested by:

• a pale pink sputum;
• the presence of foam at the mouth;
• cardiac asthma.

In the most severe cases, pulmonary edema can lead to a state of respiratory distress. It requires management by emergency medical services because it can be life-threatening.

Pulmonary edema requires rapid and appropriate medical treatment. This can be based on:

• the establishment of ventilatory assistance;
• diuretic treatment by infusion and then by mouth to eliminate water in the lungs;
• treatment targeting the cause of pulmonary edema;
• surgery in the most serious cases.

The prevention of pulmonary edema consists in limiting the risk factors as much as possible. In particular, it may be recommended to:

• maintain good eating habits;
• engage in regular physical activity;
• no smoking ;
• limit your alcohol consumption.