Indomethacin for symptomatic patent ductus arteriosus in preterm infants

Background Symptomatic patent ductus arteriosus (PDA) is associated with mortality and morbidity in preterm infants. In these infants, prophylactic use of indomethacin, a non-selective cyclooxygenase inhibitor, has demonstrated short-term clinical benefits. The effect of indomethacin in preterm infants with a symptomatic PDA remains unexplored. Objectives To determine the effectiveness and safety of indomethacin (given by any route) compared to placebo or no treatment in reducing mortality and morbidity in preterm infants with a symptomatic PDA. Search methods We used the standard search strategy of Cochrane Neonatal to search Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 7), in the Cochrane Library; Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions(R); and Cumulative Index to Nursing and Allied Health Literature (CINAHL), on 31 July 2020. We also searched clinical trials databases and the reference lists of retrieved articles for randomized controlled trials (RCTs) and quasi-RCTs. Selection criteria We included RCTs and quasi-RCTs that compared indomethacin (any dose, any route) versus placebo or no treatment in preterm infants. Data collection and analysis We used the standard methods of Cochrane Neonatal, with separate evaluation of trial quality and data extraction by at least two review authors. We used the GRADE approach to assess the certainty of evidence for the following outcomes: failure of PDA closure within one week of administration of the first dose of indomethacin; bronchopulmonary dysplasia (BPD) at 28 days' postnatal age and at 36 weeks' postmenstrual age; proportion of infants requiring surgical ligation or transcatheter occlusion; all-cause neonatal mortality; necrotizing enterocolitis (NEC) (a Bell stage 2); and mucocutaneous or gastrointestinal bleeding. Main results We included 14 RCTs (880 preterm infants). Four out of the 14 included studies were judged to have high risk of bias in one or more domains. Indomethacin administration was associated with a large reduction in failure of PDA closure within one week of administration of the first dose (risk ratio (RR) 0.30, 95% confidence interval (CI) 0.23 to 0.38; risk difference (RD) -0.52, 95% CI -0.58 to -0.45; 10 studies, 654 infants; high-certainty evidence). There may be little to no difference in the incidence of BPD (BPD defined as supplemental oxygen need at 28 days' postnatal age: RR 1.45, 95% CI 0.60 to 3.51; 1 study, 55 infants; low-certainty evidence; BPD defined as supplemental oxygen need at 36 weeks' postmenstrual age: RR 0.80, 95% CI 0.41 to 1.55; 1 study, 92 infants; low-certainty evidence) and probably little to no difference in mortality (RR 0.78, 95% CI 0.46 to 1.33; 8 studies, 314 infants; moderate-certainty evidence) with use of indomethacin for symptomatic PDA. No differences were demonstrated in the need for surgical PDA ligation (RR 0.66, 95% CI 0.33 to 1.29; 7 studies, 275 infants; moderate-certainty evidence), in NEC (RR 1.27, 95% CI 0.36 to 4.55; 2 studies, 147 infants; low-certainty evidence), or in mucocutaneous or gastrointestinal bleeding (RR 0.33, 95% CI 0.01 to 7.58; 2 studies, 119 infants; low-certainty evidence) with use of indomethacin compared to placebo or no treatment. Certainty of evidence for BPD, surgical PDA ligation, NEC, and mucocutaneous or gastrointestinal bleeding was downgraded for very serious or serious imprecision. Authors' conclusions High-certainty evidence shows that indomethacin is effective in closing a symptomatic PDA compared to placebo or no treatment in preterm infants. Evidence is insufficient regarding effects of indomethacin on other clinically relevant outcomes and medication-related adverse effects.