Unwinding old habits: deimplementation of treatment regimens for patent ductus arteriosus in preterm infants

The year 2018 marks the seventieth anniversary of Burnard's observation that patent ductus arteriosus (PDA) in infants could be recognized using phonocardiography. 1 Soon after, this method was used to demonstrate that ductal patency is often prolonged in preterm infants and is associated with greater severity of respiratory distress.Linkage of ductal patency to respiratory compromise and other adverse outcomes led to the thesis that intervention to achieve earlier ductal closure would improve results.Development of techniques for ligation of the ductus in small newborn infants in the early 1970s provided a means for doing so.With the advent of ultrasonography for diagnosing prolonged ductal patency and recognition that prostaglandin synthesis inhibitors promote ductal constriction, the stage was set for adopting strategies for early and widespread treatment to close PDA in preterm infants.The pathophysiological rationale for doing so ---reduction in aortopulmonary shunt-