Definition of Atelectasis:

Atelectasis is the collapse of part or (much less commonly) all of a lung.

See also: Pneumothorax

Causes, incidence, and risk factors:

Atelectasis is caused by a blockage of the air passages (bronchus or bronchioles) or by pressure on the outside of the lung.

It is common after surgery, or in patients who were in the hospital.

Risk factors for developing atelectasis include:

• Anesthesia
• Foreign object in the airway (most common in children)
• Lung diseases
• Mucus that plugs the airway
• Pressure on the lung caused by a buildup of fluid between the ribs and the lungs (called a pleural effusion)
• Prolonged bed rest with few changes in position
• Shallow breathing (may be caused by painful breathing)
• Tumors that block an airway