Tall, thin young men are the classic victims of a lung that suddenly collapses
Air leaking into the gap between lung and chest wall can deflate a lung without warning, often in a healthy young adult. Some sufferers wait days before seeing a doctor. Changes in air pressure seem to trigger clusters of cases, and a scuba diver can cause one by rising just a metre while holding a full breath.
Doctors divide the condition into three kinds. A primary spontaneous pneumothorax strikes people with no obvious lung disease; its cause is unknown, but being male, smoking tobacco or cannabis, a family history and a tall, lean build all raise the risk. A secondary one occurs in someone with existing lung disease, most often COPD, which accounts for roughly 70 percent of these cases, and it tends to be more dangerous because the other lung cannot compensate. The third kind follows injury, from broken ribs, penetrating wounds, blasts or medical procedures such as inserting a catheter into a chest vein.
Typical symptoms are sudden, sharp pain on one side of the chest and breathlessness. Oddly, the size of the air pocket does not track closely with how bad a person feels, and small ones can be hard to detect by examination alone. A chest x-ray, CT or ultrasound usually settles it. Newborns are affected more than any other age group, around 1 to 3 per 1000 live births, mostly within the first 72 hours.
The most feared form is the tension pneumothorax, in which damaged tissue acts as a one-way valve. Air enters but cannot escape, pressure builds and blood flow is obstructed, producing a form of shock that can be fatal unless relieved. It arises mainly during ventilation, resuscitation or trauma, and whether it genuinely occurs in spontaneous cases is debated. Divers face a particular hazard, since treatment for decompression sickness in a pressure chamber can rapidly enlarge a small leak.
Small spontaneous cases often heal by themselves with monitoring, and evidence suggests a watchful approach to primary cases works as well as intervention, with fewer serious complications. Larger ones may be drained with a needle or chest tube, and repeated episodes can lead to surgery that makes the lung's membranes stick together. Around 17 to 23 cases occur per 100,000 people each year. Italian physician Carlo Forlanini once collapsed lungs deliberately to starve tuberculosis bacteria of oxygen.
Source: Pneumothorax
