Pneumothorax is a collection of air between the lung and the chest wall that develops when air leaks out of the lung.
Pneumothorax most often occurs in newborns with stiff lungs, such as newborns with respiratory distress syndrome (see see Respiratory Distress Syndrome) or meconium aspiration syndrome (see see Meconium Aspiration Syndrome). Infrequently, it occurs as a complication from the use of continuous positive airway pressure (CPAP—a technique that allows newborns to breathe on their own while receiving slightly pressurized oxygen or air given through prongs placed in the nostrils) or a ventilator. If the pneumothorax is under pressure from CPAP or a ventilator, it can result in collapse of the lung and difficulty breathing. Also, if under pressure, the pneumothorax can compress the veins that bring blood to the heart. As a result, less blood fills the chambers of the heart, the output of the heart decreases, and the newborn's blood pressure decreases.
Air that leaks from the lungs into the tissues in the center of the chest is called pneumomediastinum. Unlike pneumothorax, this condition usually does not affect breathing.
Diagnosis and Treatment
Pneumothorax is suspected when newborns with underlying lung disorders or newborns receiving CPAP or on a ventilator develop worsening respiratory distress, a drop in blood pressure, or both. When examining these newborns, doctors may notice diminished sounds of air entering and leaving the lung on the side of the pneumothorax. In premature newborns, a fiber-optic light may be used to light up the affected side of the newborn's chest while in a darkened room (positive transillumination). This procedure is used to identify free air in the area surrounding the lungs (pleural cavity). A chest x-ray provides a definitive diagnosis.
No treatment is needed for newborns who do not have symptoms. Term newborns with mild symptoms may be placed in a small tent into which oxygen is pumped (an oxygen hood), so that they breathe air that contains more oxygen than does room air. However, if the newborn's breathing is labored or if the level of oxygen in the blood declines, and particularly if the circulation of blood is impaired, the air must be rapidly removed from the chest cavity. Air is removed from the chest cavity by using a needle and syringe. For newborns in significant distress, receiving CPAP, or on a ventilator, doctors may need to place a plastic tube into the chest cavity to continuously suction and remove air from the chest cavity. The tube can usually be removed after several days.
A pneumomediastinum can be seen on an x-ray and requires no treatment.
Last full review/revision February 2009 by Arthur E. Kopelman, MD