[Pneumoperitoneum and pneumomediastinum complicating non-invasive ventilation]

Pneumoperitoneum is known to be a rare complication of invasive mechanical ventilation. However it has not previously been described as a consequence of non-invasive ventilation.

The authors report a case of pneumoperitoneum associated with pneumomediastinum occurring in a 64-year-old patient treated for 3 years with bilevel ventilation via a nasal mask (expiratory pressure = 9 cm H2O, inspiratory pressure = 15 cm H2O) for obesity hypoventilation syndrome. Respiratory and gastroenterological investigations did not demonstrate a cause for this complication which resolved spontaneously following the cessation of ventilation. Nine months later, clinical deterioration and a worsening of blood gas parameters led to a recommencement of non-invasive mechanical ventilation at the same levels as previously. Over two years of follow up there have been no clinical or radiological signs of a recurrence of pneumomediastinum or pneumoperitoneum.

In the absence of any other explanation, barotrauma due to nasal ventilation appears to be the most likely explanation for this complication.