What Is a Collapsed Lung (Pneumothorax)?
When the muscles of the chest and diaphragm contract they expand the chest, causing the lungs to inflate. Like a balloon, the lungs stretch as they inflate. When you exhale, the muscles relax, and like a balloon that’s been released the lungs spring back. But if the air escapes from the lung and into the chest around the lung, the lung can collapse inside the chest. This can occur from the bursting of a weak spot of the lung, either from another medical condition, infection, or cancer. Or it could be caused by a puncture of the lung such as from a fractured rib. Another condition called atelectasis is like a collapse of the lung, but the air doesn’t escape into the chest. Rather the air sacs in the lung don’t adequately expand when taking a breath. This can be caused by mucus plugging or a tumor blocking the airway. Or more commonly it can occur after an operation or by lying immobile for long periods. To help prevent atelectasis, stop smoking six to eight weeks before surgery. Breathe
