Which factor is a major etiologic contributor to bronchopulmonary dysplasia?

Which factor is a major etiologic contributor to bronchopulmonary dysplasia?

• A. Short-term oxygen therapy
• B. Prolonged exposure to high concentrations of oxygen with positive-pressure ventilation
• C. Hypoxic episodes without ventilation
• D. Viral infection alone

Answer: (B)

Bronchopulmonary dysplasia arises when the immature lung of a preterm infant suffers injury from respiratory support and oxygen exposure. The strongest driver is prolonged exposure to high concentrations of oxygen combined with positive-pressure ventilation. Oxygen toxicity damages airway and alveolar epithelium and endothelium, while the added lung stretch from positive-pressure ventilation causes volutrauma and barotrauma. This injury triggers inflammation and disrupts normal lung development, leading to fewer and larger airspaces (alveolar simplification) and abnormal pulmonary vasculature, which underlies the chronic changes seen in BPD. Short-term oxygen therapy, isolated hypoxic episodes without ventilation, or viral infection can stress the lungs but do not produce the same sustained, destructive remodeling pattern that prolonged high‑oxygen exposure with mechanical ventilation does.

Bronchopulmonary dysplasia arises when the immature lung of a preterm infant suffers injury from respiratory support and oxygen exposure. The strongest driver is prolonged exposure to high concentrations of oxygen combined with positive-pressure ventilation. Oxygen toxicity damages airway and alveolar epithelium and endothelium, while the added lung stretch from positive-pressure ventilation causes volutrauma and barotrauma. This injury triggers inflammation and disrupts normal lung development, leading to fewer and larger airspaces (alveolar simplification) and abnormal pulmonary vasculature, which underlies the chronic changes seen in BPD.

Short-term oxygen therapy, isolated hypoxic episodes without ventilation, or viral infection can stress the lungs but do not produce the same sustained, destructive remodeling pattern that prolonged high‑oxygen exposure with mechanical ventilation does.