Continued uncertainty regarding treatment of patent ductus arteriosus in premature infants and the role of clinical trials.

Despite several decades of research into treatments for patent ductus arteriosus (PDA), there is continued uncertainty regarding whether, when, and how best to treat PDA and the long-term consequences. There are almost 5000 babies enrolled into clinical trials, but the questions remain largely unanswered. Many of the trials performed over the period were well designed and addressed important clinical questions, but the results are not necessarily directly applicable to the clinical management dilemmas of today since perinatal care has improved over time per se, the patient population is typically more premature, and there have been technological advances in diagnosis. This article examines some of the approaches taken, how trial designs evolved over time, especially in terms of the patient population and outcomes evaluated, and it offers points to consider when planning future research.