Necrotizing tracheobronchitis in patent ductus arteriosus-dependent cyanotic congenital heart disease

We report 2 patients with necrotizing tracheobronchitis (NTB) associated with patent ductus arteriosus-dependent cyanotic congenital heart disease. The pathologic findings suggest that hypotension and decreased tracheo-bronchial perfusion were the major contributing factors in the development of NTB. Necrotizing tracheobronchitis developed in infants with pulmonary atresia and Ebstein's anomaly with pulmonary stenosis. Both infants required prostaglandin E1 infusion from early infancy, and presented with sudden onset of dyspnea and hypercapnea. In one infant, NTB developed prior to mechanical ventilation. In the other infant, NTB developed after 4 days of mechanical ventilation. Care of both infants involved minimal pressures and FiO₂, adequate humidification, and optimal temperature of inspired gases; these factors probably did not play a role in the development or worsening of NTB. Both infants had hypotension and hypoxemia. These factors could have contributed to the development of NTB because of decreased perfusion pressure and tissue hypoxia. As the area of necrosis and its severity correlated with the area of blood supply served by the specific feeding arteries, we speculate that tissue hypoperfusion was the major cause of NTB.