ABSTRACT
Improved treatments of smaller and sicker infants with mechanical ventilation in the 1960s led to increasing survival. Soon thereafter, pulmonary sequelae were described by Northway and colleagues who introduced the term bronchopulmonary dysplasia (BPD) (1). Both the terms bronchopulmonary dysplasia (BPD) and chronic lung disease (CLD) have been used interchangeably. At a 2001 National Institutes of Health, participants recommended that the term BPD be used to describe the pulmonary sequelae of respiratory distress syndrome (RDS) and prematurity because BPD emphasized the involvement of all of the tissues of the lung, and was a term reserved solely to survivors of preterm birth (2). Since the original description by Northway, the natural history of BPD has evolved and newer definitions have been proposed. Original definitions were dichotomous based on exposure to oxygen supplementation at various time points. However, increasingly it has been recognized that dichotomous outcomes fail to adequately describe the long-term pulmonary outcomes of these fragile infants. These definitions attempt to improve the specificity of the diagnosis of BPD as an outcome measure of clinical care and research trials. This chapter discusses the definitions of BPD and the use of benchmarking techniques to compare BPD outcomes.
