Pneumothorax in association with spontaneous ventilation general anaesthesia--an unusual cause of hypoxaemia.

A 43-year-old ASA PS II male patient developed a pneumothorax while breathing pontaneously through a supraglottic airway device during a general anaesthetic. Unexplained hypoxaemia occurred after an episode of coughing. Clinical examination appeared to be normal apart from the persistent oxygen desaturation. A pneumothorax was diagnosed in the post anaesthesia care unit by chest X-ray. The pneumothorax responded to conventional management and the patient made an uneventful recovery. We recommend a high index of suspicion in any patient who coughs and later has unexplained hypoxaemia during general anaesthesia, even if a supraglottic airway device has been inserted.