What causes bronchopulmonary dysplasia?
Bronchopulmonary dysplasia occurs in severely ill infants who have received high concentrations of oxygen for long periods of time and prolonged support on respiratory ventilators during treatment for respiratory distress syndrome of the newborn. The lung tissue is injured when the high pressure needed to inflate the lungs and the high concentration of oxygen stretches
the air spaces. Injury can also be caused if a tube is placed in the trachea to deliver oxygen. The injured lung tissue becomes inflamed, which eventually leads to scarring.
The lung injury that produces bronchopulmonary dysplasia may be caused by a combination of factors: increased pressure in the lungs from mechanical ventilators or from the oxygen toxicity that occurs when the lung is exposed to very high concentrations of oxygen for prolonged periods. The delicate tissues of the lungs can become injured when the air sacs are over-stretched by the ventilation or by high oxygen levels. As a result, the lungs become inflamed and additional fluid accumulates within the lungs. Full-term newborns who have lung disease (such as pneumonia) occasionally develop bronchopulmonary dysplasia.
Risk factors for bronchopulmonary dysplasia include prematurity, respiratory infection, congenital heart disease, or other severe illness in the newborn requiring therapy with oxygen and/or ventilators. |
