Suggested citation: Bancalari E. Bronchopulmonary dysplasia: old

The more common use of antenatal steroids, surfactant therapy and improved respiratory care has changed the presentation of bronchopulmonary dysplasia (BPD) originally described by Northway et al. in 1967.1 The severe form of BPD has been replaced by a milder clinical form that presents in infants who initially have no or mild respiratory distress syndrome (RDS).2 These infants respond to surfactant therapy and require prolonged mechanical ventilation because of apnea and poor respiratory effort.3-5 Thus, these infants have not been exposed to aggressive ventilation or high inspired oxygen concentrations, the two main factors traditionally invoked in the pathogenesis of the typical form of BPD.6 This milder form of illness is the most commonly observed in extremely low birth weight infants today. Once lung damage has occurred, these infants may require mechanical ventilation and increased oxygen concentration for long periods of time with gradual weaning from ventilator and oxygen therapy after several weeks or months. Infants with more severe BPD may still evolve into progressive respiratory failure, or even death, as a result of more severe lung damage and pulmonary hypertension that can result in cor pulmonale. The reported incidence of BPD varies widely and this variation is related to differences in patient susceptibility and management, but inconsistencies in BPD definition also accounts for the variation. The diagnostic criteria for BPD are based on oxygen dependency and this can vary due to differences in altitude, the use of other methods of respiratory support such as continuous or intermittent positive airway pressure and use of drugs that can influence gas exchange, such as diuretics, respiratory stimulants or corticosteroids. Perhaps the major problem of using oxygen requirement to define BPD is the variation Bronchopulmonary dysplasia: old problem, new presentatio