Bilateral pneumothorax and pneumomediastinum after treatment with continuous positive airway pressure after orthognathic surgery.

We describe a 25-year-old woman who developed hypoxaemia secondary to pulmonary atelectasis after orthognathic surgery. Treatment with continuous positive airway pressure (CPAP) through a face-mask postoperatively was complicated by subcutaneous emphysema, pneumomediastinum, and bilateral pneumothoraces. CPAP has been advocated for the treatment of postoperative hypoxaemia, but when used in the presence of facial trauma or when the oral mucosa has been disrupted it can cause subcutaneous emphysema. We suggest that it is not used after orthognathic surgery.