Traumatic pneumomediastinum

A previously-healthy thirty-year old man presented to the Emergency Department at Hawke’s Bay Hospital with central chest pain, following blunt chest trauma whilst SCUBA diving. He was at a depth of approximately five metres, during his ascent, when he was dumped onto a rock by a wave, hitting the left side of his chest. Several hours later, he developed central chest tightness and mild dyspnoea. He had no dysphagia or abdominal pain. Examination findings showed normal vital signs, reduced air entry over left chest wall, and a “crunchy” systolic murmur. He had subcutaneous emphysema around his neck. His trachea was