Pneumopericardium associated with face-mask continuous positive airway pressure.

This is an uncommon case of a patient who developed pneumopericardium while being treated with face-mask continuous positive airway pressure (CPAP) for hypoxic respiratory failure following a coronary artery bypass graft surgery. A pneumopericardium detected by chest radiograph resolved completely after discontinuation of face-mask CPAP. Possible mechanisms that may have been involved in this unusual complication are reviewed.