Pneumothorax in the neonatal period.

The incidence of pneumothorax in the neonatal period is reviewed. Most infants who developed a pneumothorax were undergoing intermittent positive pressure ventilation. The most common underlying pathology associated with pneumothorax was idiopathic respiratory distress syndrome. This was the only condition in which a pneumothorax occurred in spontaneously breathing patients. The development of a pneumothorax was not significantly related to gestational age, birth weight, high ventilator inflation pressure, maximum fractional inspired oxygen concentration or the method of delivery. Evidence is presented to suggest that the development of a pneumothorax is not primarily a complication of ventilation but is due to the more severe pulmonary pathology of infants who require ventilatory assistance. Whatever the mechanism, prompt diagnosis and treatment mean that this common complication does not necessarily increase mortality.