Spontaneous pneumomediastinum as a result of SCUBA diving

摘要

Spontaneous pneumomediastinum is an uncommon disease defined as the nontraumatic presence of free air in the mediastinum without any apparent precipitating or underlying disease. It is a rare self-limited disorder that usually affects otherwise healthy young men. This is, however, a well known complication of Self Contained Underwater Breathing Apparatus (SCUBA) diving owing to barotrauma. The open circuit SCUBA enables the diver to breathe gas coming from a high-pressure cylinder as it comes through a regulator. This regulator reduces the pressure of the inhaled gas to an ambient pressure and thus the SCUBA allows exhalation into the water. The rapidly changing ambient pressure under water causes a variety of physiological alterations and it can result in dangerous diving accidents.