Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a chronic lung disease primarily affecting preterm infants whose lungs are still developing when exposed to various injurious factors. Premature lungs are vulnerable because they are exposed to inflammation, infection, oxygen, pressure, fluid shifts, and underdeveloped pulmonary vasculature before they are fully prepared. When an infant develops respiratory distress syndrome, infection, inflammation, or apnea of prematurity, respiratory support may be necessary to maintain adequate oxygenation and ventilation. However, this support, along with other factors, can further disrupt lung growth. Inflammation from prenatal infection, postnatal sepsis, aspiration, or prolonged respiratory support exacerbates lung injury and impairs normal development. Postnatal contributors to lung damage include ventilator-associated lung injury, oxygen toxicity, sepsis, aspiration, repeated atelectasis, and ongoing inflammation. The risk of developing BPD increases with very low birth weight, severe respiratory distress syndrome, prolonged oxygen therapy, prolonged mechanical ventilation, infection, inflammation, patent ductus arteriosus, fluid overload, poor growth, and inadequate nutrition. Oxygen exposure is a significant factor, but prematurity itself, inflammation, infection, mechanical ventilation, impaired alveolarization, and abnormal pulmonary vascular development are all central to the disease process. Clinically,...