A collapsed lung, also known as atelectasis, can be caused by many factors. It can be due to compression of the lung tissue or obstruction of the air passages. The whole lung, or a partial area of the lung may be affected. Pneumothorax and pleural effusion can cause the lung to partially collapse without closing off the airway. At this point, the lung tissue may expand with no further treatment.
- Pnueumothorax is a collection of free air outside the lung, causing it to collapse.
- Spontaneous pneumothorax is caused by a rupture of a cyst or a small sac (bleb) on the surface of the lung.
- Pneumothorax may also occur following an injury to the chest wall. This can include: a fractured rib, any penetrating injury, surgical invasion of the chest, or may be deliberately induced, in order to collapse the lung.
- Underlying lung diseases, including cystic fibrosis, chronic obstructive pulmonary disease (COPD), lung cancer, asthma, and infections of the lungs, can also be causes of a collapsed lung.
- Pneumothorax leading to possible collapsed lungs can occur spontaneously in slim young males, and males with Marfan syndrome.
- Collapsed lung due to a ruptured air pocket can be caused by diving, flying, asthma, or even stretching.