Management of the patent ductus arteriosus in the very pre-term infant

Debate about the importance of the pre-term patent ductus arteriosus (PDA) continues to rage. While consistently associated with a range of adverse outcomes, clinical trials of PDA treatment have failed to show an effect on those outcomes leading some to hypothesize that the PDA is an innocent physiological bystander. Ultrasound studies of PDA have suggested that the early post-natal haemodynamic impact in some babies may be much greater than previously thought but we still don’t know when to treat a PDA. Studies that have tested symptomatic or pre-symptomatic treatment are mainly quite dated and have not tested the effect of no treatment. Prophylactic treatment is the best-studied regimen but improvements in some short-term outcomes do not translate to any difference in longer-term outcomes. Neonatologists have been reluctant to engage in trials which test treatment against not treating at all or very rarely. Targeting treatment on the basis of the early post-natal constrictive response of the duct is currently being tested as a possible strategy.