Pneumomediastinum diagnosed by chest radiography after centrifuge training

A retrospective review of the human centrifuge training database in the Republic of Singapore Air Force was carried out for the period 1995-2006. Six cases of pneumomediastinum were reported in aircrew trainees who underwent ab initio human centrifuge training. Only two of the six cases presented with chest discomfort with or without neck pain, with the rest being incidental findings picked up during routine medical examination. The diagnoses were confirmed by chest radiographs and computed tomography scans of the thorax. This is believed to be attributable to over-zealous or incorrect performance of the anti-G straining maneuver in trainees unaccustomed to a high G environment. Trainees subsequently underwent a structured weights training program and centrifuge training profiles were reviewed and revised to allow graduated G training. All affected trainees recovered uneventfully with conservative management, and were able to return to flying training.