The treatment of patent ductus arteriosus in preterm infants. A review and overview of randomized trials.

Patent ductus arteriosus (PDA) is a common problem in very preterm infants. It results in a significant left-to-right shunt and an increase in left ventricular output. Pulmonary compliance can be reduced. Systemic effects result from the diastolic steal and retrograde diastolic blood flow. Randomized controlled trials of PDA closure fall into three groups: (i) prophylactic treatment in the first 24 h, (ii) pre-symptomatic treatment on ultrasound evidence of a PDA or the first clinical signs and (iii) treatment when it becomes haemodynamically significant. Prophylactic treatment with indomethacin reduces the incidence of intraventricular haemorrhage. All the trials have a decreased need to treat a subsequent PDA in the treatment group. There are no other improvements in outcome, without any change in mortality, bronchopulmonary dysplasia, necrotizing enterocolitis or retinopathy of prematurity. Clinical decisions on the treatment of the ductus should be individualized and based on the gestation of the baby, the respiratory condition and the size of the ductal shunt.