ABSTRACT
Improvements in strategies for care of preterm infants with respiratory distress over the past decade have changed the major clinical conditions associated with development of chronic pulmonary disease, as reflected by a requirement for oxygen support at 28 days of age or a gestational age of 36 weeks. Two decades ago, the factors most strongly related to development of bronchopulmonary dysplasia (BPD) were prolonged exposure to high inspired oxygen concentrations and barotrauma, as indicated by high peak inspiratory and mean airway pressures, particularly in preterm infants. As antenatal induction of lung maturation by maternal steroid therapy, reduction of supplemental oxygen, and positive-pressure ventilation requirements by surfactant replacement therapy, and refinement of conventional and high-frequency ventilation strategies to minimize barotrauma have reduced the mortality and morbidity of chronic lung disease among premature infants, pulmonary infection appears to have become a more significant contributor to the pathogenesis of chronic oxygen dependency in infancy. The goal of this chapter is to review the epidemiological and pathogenetic observations that may illuminate this relation.
