The definition of Classic Bronchopulmonary Dysplasia (BPD), was first made in 1967. Today, this definition is adopted as the old BPD; 30-37 weeks of gestational age, developing in patients with severe respiratory distress, severe damage of the large airways, interstitial and alveolar edema, fibrosis and characterized by areas of excessive aeration in the form of widespread small airways disease. Identifying of more BPD, preterm newborn infants with respiratory distress syndrome (RDS), is due to their being ventilated with high pressure and oxygen, resulting in oxygen toxicity and connected to barotrauma. However, in recent years, antenatal steroid therapy can be made more uniform, with prophylactic surfactant applications and as a result of modern ventilation techniques to be used at very small gestational age, preterms have begun d tosurvive. In parallel with this group of preterms, a new concept BPD has emerged. In “the new BPD,” definition, in smaller babies of (24-28) weeks of gestation, RDS is initially absent or mild, but even though they are not ventilated with high oxygen and high pressure, after a few days or few weeks an increasing deterioration in lung function and increased need for oxygen is known to ocur. This period of deterioration is usually associated with a systemic bacterial infection or patent ductus arteriosus (PDA). In the lung parenchyma of the Classical type BPD; bronchial mucosal hyperplasia and metaplasia, collapse and emphysema in some places, interstitial edema and increase of fibrotic tissue was found. In lung parenchyma of New BPD; fewness of gas exchange areas, decrease in the number of capillary vessels and alveoli, less emphysema and minimal fibrosis was found but the injury was more diffuse. In this review, BPD and new views about the BPDwere discussed.

Keywords: Bronchopulmonary dysplasia, newborn, prematurity, lung