Superoxide dismutase for bronchopulmonary dysplasia in preterm infants.

BACKGROUND: Free oxygen radicals have been implicated in the pathogenesis of bronchopulmonary dysplasia (BPD) in preterm infants. Superoxide dismutase (SOD) is a naturally occurring enzyme which provides a defense against such oxidant injury. Providing supplementary SOD has been tested in clinical trials to prevent BPD in preterm infants. OBJECTIVES: To determine the efficacy and safety of SOD in the prevention and treatment of BPD on mortality and other complications of prematurity in infants at risk for, or having BPD. SEARCH METHODS: We searched CENTRAL, PubMed, Embase, and three trials registers on 22 September 2022 together with reference checking, citation searching and contact with study authors to identify additional studies. SELECTION CRITERIA: Randomized, quasi-randomized and cluster-randomized controlled trials (RCTs) where the participants were preterm infants who had developed, or were at risk of developing BPD, and who were randomly allocated to receive either SOD (in any form, by any route, any dose, anytime) or placebo, or no treatment. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were BPD defined as an oxygen requirement at 28 days, BPD defined as oxygen at 36 weeks' postmenstrual age, neonatal mortality, mortality prior to discharge, and BPD or death at 36 weeks' postmenstrual age. We reported risk ratio (RR) and risk difference (RD) with 95% confidence intervals (CIs) for the dichotomous outcomes. We used GRADE to assess certainty of evidence for each outcome. MAIN RESULTS: We included three RCTs (380 infants) on SOD administration in preterm infants at risk for BPD, and no studies in preterm infants with evolving BPD / early respiratory insufficiency. The evidence is very uncertain about the effect of SOD on BPD defined as an oxygen requirement at 28 days (RR 1.09, 95% CI 0.94 to 1.26; RD 0.06, 95% CI -0.05 to 0.16, 1 study, 302 infants; I2 for RR and RD not applicable), BPD defined as oxygen at 36 weeks' postmenstrual age (RR 0.96, 95% CI 0.72 to 1.29; RD -0.01, 95% CI -0.11 to 0.09, 2 studies, 335 infants; I2 for RR and RD = 0%), neonatal mortality (RR 0.98, 95% CI 0.57 to 1.68; RD -0.00, 95% CI -0.08 to 0.07, 2 studies, 335 infants; I2 for RR and RD = 0%), and mortality prior to discharge (RR 1.20, 95% CI 0.53 to 2.71; RD 0.04, 95% CI -0.14 to 0.23, 2 studies, 78 infants; I2 for RR and RD = 0%). No studies reported BPD or death at 36 weeks' postmenstrual age. The evidence is very uncertain about the effect of SOD on retinopathy of prematurity any stage (RR 0.95, 95% CI 0.78 to 1.15; RD -0.03, 95% CI -0.15 to 0.08, 2 studies, 335 infants; I2for RR = 0%, I2 for RD = 8%), and severe retinopathy of prematurity (ROP) (RR 0.97, 95% CI 0.57 to 1.65; RD -0.01, 95% CI -0.10 to 0.09, 1 study, 244 infants; I2 for RR and RD not applicable). No studies reported moderate to severe neurodevelopmental outcome at 18 to 24 months. Certainty of evidence was very low for all outcomes. We identified no ongoing trials. AUTHORS' CONCLUSIONS: The evidence is very uncertain about the effect of SOD on BPD defined as an oxygen requirement at 28 days, BPD defined as oxygen at 36 weeks' postmenstrual age, neonatal mortality and mortality prior to discharge compared to placebo. No studies reported BPD or death at 36 weeks' postmenstrual age and need for supplemental oxygen. The evidence is very uncertain about the effect of SOD on retinopathy of prematurity any stage and severe retinopathy of prematurity. No studies reported moderate to severe neurodevelopmental outcome at 18 to 24 months. The effects of SOD in preterm infants has not been reported in any trial in the last few decades, considering that the most recent trial on SOD in preterm infants was conducted in 1997/1998, and no new studies are ongoing. In the light of the limited available evidence, new data from preclinical and observational studies are needed to justify the conduction of new RCTs. Observational studies might report how SOD is administered, including indication, dose and association with relevant outcomes such as mortality, BPD and long-term neurodevelopment.

Sunlight for the prevention and treatment of hyperbilirubinemia in term and late preterm neonates.

BACKGROUND: Acute bilirubin encephalopathy (ABE) and the other serious complications of severe hyperbilirubinemia in the neonate occur far more frequently in low- and middle-income countries (LMIC). This is due to several factors that place babies in LMIC at greater risk for hyperbilirubinemia, including increased prevalence of hematologic disorders leading to hemolysis, increased sepsis, less prenatal or postnatal care, and a lack of resources to treat jaundiced babies. Hospitals and clinics face frequent shortages of functioning phototherapy machines and inconsistent access to electricity to run the machines. Sunlight has the potential to treat hyperbilirubinemia: it contains the wavelengths of light that are produced by phototherapy machines. However, it contains harmful ultraviolet light and infrared radiation, and prolonged exposure has the potential to lead to sunburn, skin damage, and hyperthermia or hypothermia. OBJECTIVES: To evaluate the efficacy of sunlight administered alone or with filtering or amplifying devices for the prevention and treatment of clinical jaundice or laboratory-diagnosed hyperbilirubinemia in term and late preterm neonates. SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search CENTRAL (2019, Issue 5), MEDLINE, Embase, and CINAHL on 2 May 2019. We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials (RCTs), quasi-RCTs, and cluster RCTs. We updated the searches on 1 June 2020. SELECTION CRITERIA: We included RCTs, quasi-RCTs, and cluster RCTs. We excluded crossover RCTs. Included studies must have evaluated sunlight (with or without filters or amplification) for the prevention and treatment of hyperbilirubinemia or jaundice in term or late preterm neonates. Neonates must have been enrolled in the study by one-week postnatal age. DATA COLLECTION AND ANALYSIS: We used standard methodologic procedures expected by Cochrane. We used the GRADE approach to assess the certainty of evidence. Our primary outcomes were: use of conventional phototherapy, treatment failure requiring exchange transfusion, ABE, chronic bilirubin encephalopathy, and death. MAIN RESULTS: We included three RCTs (1103 infants). All three studies had small sample sizes, were unblinded, and were at high risk of bias. We planned to undertake four comparisons, but only found studies reporting on two. Sunlight with or without filters or amplification compared to no treatment for the prevention and treatment of hyperbilirubinemia in term and late preterm neonates One study of twice-daily sunlight exposure (30 to 60 minutes) compared to no treatment reported the incidence of jaundice may be reduced (risk ratio [RR] 0.61, 95% confidence interval [CI] 0.45 to 0.82; risk difference [RD] -0.14, 95% CI -0.22 to -0.06; number needed to treat for an additional beneficial outcome [NNTB] 7, 95% CI 5 to 17; 1 study, 482 infants; very low-certainty evidence) and the number of days that an infant was jaundiced may be reduced (mean difference [MD] -2.20 days, 95% CI -2.60 to -1.80; 1 study, 482 infants; very low-certainty evidence). There were no data on safety or potential harmful effects of the intervention. The study did not assess use of conventional phototherapy, treatment failure requiring exchange transfusion, ABE, and long-term consequences of hyperbilirubinemia. The study showed that sunlight therapy may reduce rehospitalization rates within seven days of discharge for treatment for hyperbilirubinemia, but the evidence was very uncertain (RR 0.55, 95% CI 0.27 to 1.11; RD -0.04, -0.08 to 0.01; 1 study, 482 infants; very low-certainty evidence). Sunlight with or without filters or amplification compared to other sources of phototherapy for the treatment of hyperbilirubinemia in infants with confirmed hyperbilirubinemia Two studies (621 infants) compared the effect of filtered-sunlight exposure to other sources of phototherapy in infants with confirmed hyperbilirubinemia. Filtered-sunlight phototherapy (FSPT) and conventional or intensive electric phototherapy led to a similar number of days of effective treatment (broadly defined as a minimal increase of total serum bilirubin in infants less than 72 hours old and a decrease in total serum bilirubin in infants more than 72 hours old on any day that at least four to five hours of sunlight therapy was available). There may be little or no difference in treatment failure requiring exchange transfusion (typical RR 1.00, 95% CI 0.06 to 15.73; typical RD 0.00, 95% CI -0.01 to 0.01; 2 studies, 621 infants; low-certainty evidence). One study reported ABE, and no infants developed this outcome (RR not estimable; RD 0.00, 95% CI -0.02 to 0.02; 1 study, 174 infants; low-certainty evidence). One study reported death as a reason for study withdrawal; no infants were withdrawn due to death (RR not estimable; typical RD 0.00, 95% CI -0.01 to 0.01; 1 study, 447 infants; low-certainty evidence). Neither study assessed long-term outcomes. Possible harms: both studies showed a probable increased risk for hyperthermia (body temperature greater than 37.5 °C) with FSPT (typical RR 4.39, 95% CI 2.98 to 6.47; typical RD 0.30, 95% CI 0.23 to 0.36; number needed to treat for an additional harmful outcome [NNTH] 3, 95% CI 2 to 4; 2 studies, 621 infants; moderate-certainty evidence). There was probably no difference in hypothermia (body temperature less than 35.5 °C) (typical RR 1.06, 95% CI 0.55 to 2.03; typical RD 0.00, 95% CI -0.03 to 0.04; 2 studies, 621 infants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: Sunlight may be an effective adjunct to conventional phototherapy in LMIC settings, may allow for rotational use of limited phototherapy machines, and may be preferable to families as it can allow for increased bonding. Filtration of sunlight to block harmful ultraviolet light and frequent temperature checks for babies under sunlight may be warranted for safety. Sunlight may be effective in preventing hyperbilirubinemia in some cases, but these studies have not demonstrated that sunlight alone is effective for the treatment of hyperbilirubinemia given its sporadic availability and the low or very low certainty of the evidence in these studies.