The rate of<unk>  varies among institutions, which may reflect neonatal risk factors, care practices (e.g., target levels for acceptable oxygen saturation), and differences in the clinical definitions of<unk> .
Bronchopulmonary dysplasia
Bronchomalacia
Tracheobronchomalacia
Tracheomalacia
Respiratory bronchiolitis
Asthma
Malacia
Emphysema