Atelectasis is the collapse of part or all of a lung. It is caused by a blockage of the air passages (bronchus or bronchioles) or by pressure on the lung.

See also: Pneumothorax

Risk factors for atelectasis include anesthesia, prolonged bed rest with few changes in position, shallow breathing, and underlying lung diseases. Mucus that plugs the airway, foreign objects (common in children) in the airway, and tumors that obstruct the airway may lead to atelectasis.

In an adult, small regions of atelectasis are usually not life-threatening. Unaffected parts of the lung can compensate for the loss of function in the affected area. Large-scale atelectasis may be life-threatening, especially in someone who has another lung disease or illness. In a baby or small child, lung collapse due to a mucus obstruction or other causes can be life-threatening.

Massive atelectasis may result in the collapse of a lung.

• Breathing difficulty
• Chest pain
• Cough

• Chest x-ray
• Bronchoscopy

The goal of treatment is to remove pulmonary (lung) secretions and re-expand the affected lung tissue.

The following are treatments for atelectasis:

• Use aerosolized respiratory treatments to open the airway.
• Position the body on the unaffected side to allow the lung to re-expand.
• Remove any obstruction by bronchoscopy or another procedure.
• Perform deep breathing exercises (incentive spirometry).
• Clap (percussion) on the chest to loosen mucus.
• Tilt the body (postural drainage) so that the head is lower than the chest to drain mucus.
• Treat a tumor or underlying condition, if present.

The collapsed lung usually re-inflates gradually once the obstruction has been removed. However, some residual scarring or damage may occur.

Pneumonia may develop rapidly after atelectasis.

Call your health care provider if you develop symptoms of atelectasis.

• Keep small objects out of the reach of young children.
• Maintain deep breathing after anesthesia.
• Encourage movement and deep breathing in anyone who is bedridden for long periods.

Mason RJ, Broaddus VC, Murray JF, Nadel JA. Mason, Murray & Nadel's Textbook of Respiratory Medicine. 4th ed. Philadelphia, Pa:Saunders; 2005.

Westerdahl E, Lindmark B, Eriksson T, Friberg O, Hedenstierna G, Tenling A. Deep-breathing exercises reduce atelectasis and improve pulmonary function after coronary artery bypass surgery. Chest. November 2005;128:3482-3488.