Two-year outcomes of a randomized controlled trial of inhaled nitric oxide in premature infants

Neurodevelopmental outcomes of preterm neonates receiving rescue inhaled nitric oxide in the first week of age: a cohort study

OBJECTIVE

To assess the neurodevelopmental outcomes of preterm neonates who received inhaled nitric oxide (iNO) in the first week of age for hypoxaemic respiratory failure (HRF).

METHODS

In this retrospective cohort study, we included neonates born at <29 weeks gestational age (GA) between January 2010 and December 2018 who had a neurodevelopmental assessment at 18-24 months corrected age (CA) at one of the Canadian Neonatal Follow-Up Network clinics. The primary outcome was neurodevelopmental impairment (NDI). We performed propensity score-matched analysis to compare the outcomes of those who received and did not receive iNO.

RESULTS

Of the 5612 eligible neonates, 460 (8.2%) received iNO in the first week of age. Maternal age, receipt of antenatal corticosteroids, GA and birth weight were lower in the iNO group compared with the no-iNO group. Neonates in the iNO group had higher illness severity scores and higher rates of preterm prolonged rupture of membranes and were small for GA. Severe brain injury, bronchopulmonary dysplasia and mortality were higher in the iNO group. Of the 4889 survivors, 3754 (77%) neonates had follow-up data at 18-24 months CA. After propensity score matching, surviving infants who received rescue iNO were not associated with higher odds of NDI (adjusted OR 1.34; 95% CI 0.85 to 2.12).

CONCLUSIONS

In preterm neonates <29 weeks GA with HRF, rescue iNO use was not associated with worse neurodevelopmental outcomes among survivors who were assessed at 18-24 months CA.

Efficacy of inhaled nitric oxide in preterm infants ≤ 34 weeks: a systematic review and meta-analysis of randomized controlled trials

Background: The effect of inhaled nitric oxide (iNO) in neonates >34 weeks on improving respiration is well documented. However, the efficacy of iNO in preterm infants ≤34 weeks remains controversial. Objectives: The main purpose of this review is to assess the effectiveness and safety of iNO treatment in preterm infants ≤34 weeks. Search methods: We systematically searched PubMed, Embase and Cochrane Libraries from their inception to 1 June 2023. We also reviewed the reference lists of retrieved studies. Selection criteria: Our study involved randomized controlled trials on preterm infants ≤34 weeks, especially those receiving iNO treatment, and mainly assessed outcomes such as bronchopulmonary dysplasia (BPD) and mortality. Two authors independently reviewed these trials, extracted data, and evaluated study biases. Disagreements were resolved by consensus. We used the GRADE method to assess evidence quality. Results: Our research included a total of 17 studies involving 4,080 neonates and 7 follow-up studies. The synthesis of results showed that in neonates, iNO treatment reduced the incidence of BPD (RR: 0.92; 95% CI: 0.86-0.98). It also decreased the composite outcome of death or BPD (RR: 0.94; 95% CI: 0.90-0.98), without increasing the risk of short-term (such as intraventricular hemorrhage, periventricular leukomalacia) and long-term neurological outcomes (including Bayley mental developmental index <70, cerebral palsy and neurodevelopmental impairment). Furthermore, iNO did not significantly affect other neonatal complications like sepsis, pulmonary hemorrhage, necrotizing enterocolitis, and symptomatic patent ductus arteriosus. Subgroup analysis revealed that iNO significantly reduced BPD incidence in neonates at 36 weeks under specific intervention conditions, including age less than 3 days, birth weight over 1,000 g, iNO dose of 10 ppm or higher, or treatment duration exceeding 7 days (p < 0.05). Conclusion: Inhaled NO reduced the incidence of BPD in neonates at 36 weeks of gestation, and the effect of the treatment depended on neonatal age, birth weight, duration and dose of iNO. Therefore, iNO can be considered a promising treatment for the potential prevention of BPD in premature infants. More data, however, would be needed to support nitric oxide registration in this specific patient population, to minimize its off-label use.

Epidemiologic evaluation of inhaled nitric oxide use among neonates with gestational age less than 35 weeks

BACKGROUND AND OBJECTIVES

The use of inhaled nitric oxide (iNO) in +late preterm and term infants with pulmonary hypertension is Food and Drug Administration (FDA) approved and has improved outcomes and survival. iNO use is not FDA approved for preterm infants and previous studies show no mortality benefit. The objectives were 1) to determine the usage of iNO among preterm neonates <35 weeks before and after the 2010 National Institutes of Health consensus statement and 2) to evaluate characteristics and outcomes among preterm neonates who received iNO.

METHODS

This is a population-based cross-sectional study. Billing and procedure codes were used to determine iNO usage. Data were queried from the National Inpatient Sample from 2004 to 2016. Neonates were included if gestational age was <35 weeks. The epochs were spilt into 2004-2010 (Epoch 1) and 2011-2016 (Epoch 2). Prevalence of iNO use, mortality, bronchopulmonary dysplasia (BPD), intraventricular hemorrhage, length of stay, mechanical ventilation, and cost of hospitalization.

RESULTS

There were 4865 preterm neonates <35 weeks who received iNO. There was a significant increase in iNO use during Epoch 2 (p < 0.001). There was significantly higher use in Epoch 2 among neonates small for gestational age (SGA) 2.3% versus 7.2%, congenital heart disease (CHD) 11.1% versus 18.6%, and BPD 35.2% versus 46.8%. Mortality was significantly lower in Epoch 2 19.8% versus 22.7%.

CONCLUSION

Usage of iNO was higher after the release of the consensus statement. The increased use of iNO among preterm neonates may be targeted at specific high-risk populations such as SGA and CHD neonates. There was lower mortality in Epoch 2; however, the cost was doubled.

Inhaled nitric oxide (iNO) for preventing prematurity-related bronchopulmonary dysplasia (BPD): 7-year follow-up of the European Union Nitric Oxide (EUNO) trial

OBJECTIVES

Most studies of inhaled nitric oxide (iNO) for prevention of bronchopulmonary dysplasia (BPD) in premature infants have focused on short-term mortality and morbidity. Our aim was to determine the long-term effects of iNO.

METHODS

A 7-year follow-up was undertaken of infants entered into a multicenter, double-blind, randomized, placebo-controlled trial of iNO for prevention of BPD in premature infants born between 24 and 28 weeks plus six days of gestation. At 7 years, survival and hospital admissions since the 2-year follow-up, home oxygen therapy in the past year, therapies used in the previous month and growth assessments were determined. Questionnaires were used to compare general health, well-being, and quality of life.

RESULTS

A total of 305 children were assessed. No deaths were reported. Rates of hospitalization for respiratory problems (6.6 vs. 10.5%, iNO and placebo group, respectively) and use of respiratory medications (6.6 vs. 9.2%) were similar. Two patients who received iNO and one who received placebo had received home oxygen therapy. There were no significant differences in any questionnaire-documented health outcomes.

CONCLUSIONS

iNO for prevention of BPD in very premature infants with respiratory distress did not result in long-term benefits or adverse long-term sequelae. In the light of current evidence, routine use of iNO cannot be recommended for prevention of BPD in preterm infants.

The immediate efficacy of inhaled nitric oxide treatment in preterm infants with acute respiratory failure during neonatal transport

AIM

The aim of our review was to describe the clinical response to inhaled nitric oxide (iNO) in a series of preterm babies in respiratory failure during uplift transfers to a neonatal intensive care unit.

METHODS

We performed a retrospective review of critical newborns with gestational age <34⁺⁰  weeks transferred from January 2013 to December 2018. Data were extracted from our Clinical Information System for transport. The primary measure of this review was to assess whether a significant improvement in the oxygenation saturation index (OSI) occurred following the use of iNO.

RESULTS

Thirty preterm babies <34⁺⁰  weeks were included in our review. OSI, as a measure of oxygenation, did not statistically improve as an immediate response to iNO from referral to receiving hospital (17.1 vs 16.4; P = .7). We found that pH (7.15 vs 7.29; P = .004) and pCO2 (8.1 vs 6.3; P = .05) significantly improved probably based on ventilation management.

CONCLUSION

Following the recommendations of the American Academy of Paediatrics and other organizations, iNO should not routinely be used during the neonatal transfer of preterm babies <34⁺⁰ in respiratory failure. We need to conduct further studies to establish which selected preterm patients would benefit from being treated with iNO.

Do effects of early life interventions on linear growth correspond to effects on neurobehavioural development? A systematic review and meta-analysis

BACKGROUND

Faltering in linear growth and neurobehavioural development during early childhood are often assumed to have common causes because of their consistent association. This notion has contributed to a global focus on the promotion of nutrition during pregnancy and childhood to improve both conditions. Our aim was to assess whether effects of interventions on linear growth are associated with effects on developmental scores and to quantify these associations.

METHODS

In this systematic review and meta-analysis, we included randomised trials done during pregnancy and in children aged 0-5 years that reported effects of any intervention on length-for-age or height-for-age Z scores (LAZ or HAZ) and on any of the following outcomes: motor, cognitive or mental, language, and social-emotional or behavioural development. We searched MEDLINE (Ovid), CINAHL (EBSCO), and PsycINFO (EBSCO) from database inception to June 25, 2019. Study-level data were extracted and, when required, authors were contacted for missing information. We calculated weighted meta-regression coefficients of the association between standardised effect sizes of interventions on LAZ or HAZ and developmental outcome scores and calculated pooled effect sizes for different types of intervention.

FINDINGS

Of the 7207 studies identified, we included 75 studies with 122 comparisons between intervention and control groups and outcomes reported for 72 275 children. Across all interventions, effect sizes on LAZ or HAZ were significantly associated with effect sizes on social-emotional scores (β 0·23, 95% CI 0·05 to 0·41; p=0·02), but not on cognitive (0·18, -0·36 to 0·72; p=0·51), language (0·12, -0·07 to 0·31; p=0·21), or motor development scores (0·23, -0·05 to 0·50; p=0·11). In studies that provided nutritional supplements, we observed positive significant pooled effect sizes on all five outcomes of LAZ or HAZ (effect size 0·05, 95% CI 0·01-0·09; p=0·01; n=50), cognitive or mental (0·06, 0·03-0·10; p<0·01; n=38), language (0·08, 0·03-0·13; p=0·01; n=21), motor (0·08, 0·04-0·12; p<0·01; n=41), and social-emotional (0·07, 0·02-0·12; p=0·01; n=20) scores. The effect sizes of nutritional supplementation on LAZ or HAZ scores were significantly associated with effect sizes on cognitive (β 0·40, 95% CI 0·04-0·77; p=0·049) and motor (0·43, 0·11-0·75; p=0·01) scores. In the 14 interventions promoting responsive care and learning opportunities, the pooled effect size on LAZ or HAZ score was not significant (-0·01, 95% CI -0·07 to 0·05; p=0·74), but pooled effect sizes on cognitive, language, and motor scores were 4 to 5 times larger (range 0·38-0·48) than the pooled effect sizes of nutritional supplementation (0·05-0·08).

INTERPRETATION

In nutritional supplementation interventions, improvements in linear growth were associated with small improvements in child development, whereas nurturing and stimulation interventions had significant effects on child development but no effects on linear growth. The determinants of linear growth and neurodevelopment are only partly shared. To nurture thriving individuals and communities, interventions should specifically target determinants of neurodevelopment and not simply linear growth.

FUNDING

University of California Davis, US Department of Agriculture National Institute of Food and Agriculture.

Effect of Inhaled Nitric Oxide on Survival Without Bronchopulmonary Dysplasia in Preterm Infants: A Randomized Clinical Trial

IMPORTANCE

Bronchopulmonary dysplasia (BPD) occurs in approximately 40% of infants born at younger than 30 weeks' gestation and is associated with adverse pulmonary and neurodevelopmental outcomes.

OBJECTIVE

To test whether administration of inhaled nitric oxide to preterm infants requiring positive pressure respiratory support on postnatal days 5 to 14 improves the rate of survival without BPD.

DESIGN, SETTING, AND PARTICIPANTS

This intent-to-treat study was a randomized clinical trial performed at 33 US and Canadian neonatal intensive care units. Participants included 451 neonates younger than 30 weeks' gestation with birth weight less than 1250 g receiving mechanical ventilation or positive pressure respiratory support on postnatal days 5 to 14. Enrollment spanned from December 23, 2009, to April 23, 2012, and neurodevelopmental outcome studies were completed by April 4, 2014.

INTERVENTIONS

Placebo (nitrogen) or inhaled nitric oxide initiated at 20 ppm was decreased to 10 ppm between 72 and 96 hours after starting treatment and then to 5 ppm on day 10 or 11. Infants remained on the 5-ppm dose until completion of therapy (24 days).

MAIN OUTCOMES AND MEASURES

The primary outcome was the rate of survival without BPD at 36 weeks' postmenstrual age (PMA). Secondary outcomes included BPD severity, postnatal corticosteroid use, respiratory support, survival, and neurodevelopmental outcomes at 18 to 24 months' PMA.

RESULTS

In total, 222 infants (52.3% male [n = 116]) received placebo, and 229 infants (50.2% male [n = 115]) received inhaled nitric oxide. Their mean (SD) gestation was 25.6 (1.5) vs 25.6 (1.4) weeks, and their mean (SD) birth weight was 750 (164) vs 724 (160) g. Survival without BPD at 36 weeks' PMA was similar between the placebo and inhaled nitric oxide groups (31.5% [n = 70] vs 34.9% [n = 80]) (odds ratio, 1.17; 95% CI, 0.79-1.73). Rates for severe BPD (26.6% [55 of 207] vs 20.5% [43 of 210]) and postnatal corticosteroid use for BPD (41.0% [91 of 222] vs 41.5% [95 of 229]) and the mean (SD) days of positive pressure respiratory support (55 [40] vs 54 [42]), oxygen therapy (88 [41] vs 91 [59]), and hospitalization (105 [37] vs 108 [54]) were equivalent between the 2 groups. No differences in the incidence of common morbidities were observed. Respiratory outcomes on discharge to home, at 1 year, and at age 18 to 24 months' PMA and neurodevelopmental assessments at 18 to 24 months' PMA did not differ between groups.

CONCLUSIONS AND RELEVANCE

Inhaled nitric oxide, initiated at 20 ppm on postnatal days 5 to 14 to high-risk preterm infants and continued for 24 days, appears to be safe but did not improve survival without BPD at 36 weeks' PMA or respiratory and neurodevelopmental outcomes at 18 to 24 months' PMA.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00931632.

Inhaled nitric oxide for respiratory failure in preterm infants

BACKGROUND

Inhaled nitric oxide (iNO) is effective in term infants with hypoxic respiratory failure. The pathophysiology of respiratory failure and the potential risks of iNO differ substantially in preterm infants, necessitating specific study in this population.

OBJECTIVES

To determine effects of treatment with inhaled nitric oxide (iNO) on death, bronchopulmonary dysplasia (BPD), intraventricular haemorrhage (IVH) or other serious brain injury and on adverse long-term neurodevelopmental outcomes in preterm newborn infants with hypoxic respiratory failure.Owing to substantial variation in study eligibility criteria, which decreases the utility of an overall analysis, we divided participants post hoc into three groups: (1) infants treated over the first three days of life because of defects in oxygenation, (2) preterm infants with evidence of pulmonary disease treated routinely with iNO and (3) infants treated later (after three days of age) because of elevated risk of BPD.

SEARCH METHODS

We used standard methods of the Cochrane Neonatal Review Group. We searched MEDLINE, Embase, Healthstar and the Cochrane Central Register of Controlled Trials in the Cochrane Library through January 2016. We also searched the abstracts of the Pediatric Academic Societies.

SELECTION CRITERIA

Eligible for inclusion were randomised and quasi-randomised studies in preterm infants with respiratory disease that compared effects of iNO gas versus control, with or without placebo.

DATA COLLECTION AND ANALYSIS

We used standard methods of the Cochrane Neonatal Review Group and applied the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the quality of evidence.

MAIN RESULTS

We found 17 randomised controlled trials of iNO therapy in preterm infants. We grouped these trials post hoc into three categories on the basis of entry criteria: treatment during the first three days of life for impaired oxygenation, routine use in preterm babies along with respiratory support and later treatment for infants at increased risk for bronchopulmonary dysplasia (BPD). We performed no overall analyses.Eight trials providing early rescue treatment for infants on the basis of oxygenation criteria demonstrated no significant effect of iNO on mortality or BPD (typical risk ratio (RR) 0.94, 95% confidence interval (CI) 0.87 to 1.01; 958 infants). Four studies examining routine use of iNO in infants with pulmonary disease reported no significant reduction in death or BPD (typical RR 0.94, 95% CI 0.87 to 1.02; 1924 infants), although this small effect approached significance. Later treatment with iNO based on risk of BPD (three trials) revealed no significant benefit for this outcome in analyses of summary data (typical RR 0.92, 95% CI 0.85 to 1.01; 1075 infants).Investigators found no clear effect of iNO on the frequency of all grades of IVH nor severe IVH. Early rescue treatment was associated with a non-significant 20% increase in severe IVH.We found no effect on the incidence of neurodevelopmental impairment.

AUTHORS' CONCLUSIONS

iNO does not appear to be effective as rescue therapy for the very ill preterm infant. Early routine use of iNO in preterm infants with respiratory disease does not prevent serious brain injury or improve survival without BPD. Later use of iNO to prevent BPD could be effective, but current 95% confidence intervals include no effect; the effect size is likely small (RR 0.92) and requires further study.

Inhaled nitric oxide therapy for pulmonary disorders of the term and preterm infant

The 21st century began with the FDA approval of inhaled nitric oxide therapy for the treatment of neonatal hypoxic respiratory failure associated with pulmonary hypertension in recognition of the 2 randomized clinical trials demostrating a significant reduction in the need for extracorporeal support in the term and near-term infant. Inhaled nitric oxide is one of only a few therapeutic agents approved for use through clinical investigations primarily in the neonate. This article provides an overview of the pertinent biology and chemistry of nitric oxide, discusses potential toxicities, and reviews the results of pertinent clinical investigations and large randomized clinical trials including neurodevelopmental follow-up in term and preterm neonates. The clinical investigations conducted by the Eunice Kennedy Shriver NICHD Neonatal Research Network will be discussed and placed in context with other pertinent clinical investigations exploring the efficacy of inhaled nitric oxide therapy in neonatal hypoxic respiratory failure.

Major discrepancies between what clinical trial registries record and paediatric randomised controlled trials publish

BACKGROUND

Whether information from clinical trial registries (CTRs) and published randomised controlled trial (RCTs) differs remains unknown. Knowing more about discrepancies should alert those who rely on RCTs for medical decision-making to possible dissemination or reporting bias. To provide help in critically appraising research relevant for clinical practice we sought possible discrepancies between what CTRs record and paediatric RCTs actually publish. For this purpose, after identifying six reporting domains including funding, design, and outcomes, we collected data from 20 consecutive RCTs published in a widely read peer-reviewed paediatric journal and cross-checked reported features with those in the corresponding CTRs.

METHODS

We collected data for 20 unselected, consecutive paediatric RCTs published in a widely read peer-reviewed journal from July to November 2013. To assess discrepancies, two reviewers identified and scored six reporting domains: funding and conflict of interests; sample size, inclusion and exclusion criteria or crossover; primary and secondary outcomes, early study completion, and main outcome reporting. After applying the Critical Appraisal Skills Programme (CASP) checklist, five reviewer pairs cross-checked CTRs and matching RCTs, then mapped and coded the reporting domains and scored combined discrepancy as low, medium and high.

RESULTS

The 20 RCTs were registered in five different CTRs. Even though the 20 RCTs fulfilled the CASP general criteria for assessing internal validity, 19 clinical trials had medium or high combined discrepancy scores for what the 20 RCTs reported and the matched five CTRs stated. All 20 RCTs selectively reported or failed to report main outcomes, 9 had discrepancies in declaring sponsorship, 8 discrepancies in the sample size, 9 failed to respect inclusion or exclusion criteria, 11 downgraded or modified primary outcome or upgraded secondary outcomes, and 13 completed early without justification. The CTRs for seven trials failed to index automatically the URL address or the RCT reference, and for 12 recorded RCT details, but the authors failed to report the results.

CONCLUSIONS

Major discrepancies between what CTRs record and paediatric RCTs publish raise concern about what clinical trials conclude. Our findings should make clinicians, who rely on RCT results for medical decision-making, aware of dissemination or reporting bias. Trialists need to bring CTR data and reported protocols into line with published data.

Preliminary findings of long-term neurodevelopmental outcomes of infants treated with intravenous fat emulsion reduction for the management of parenteral nutrition-associated cholestasis

INTRODUCTION

Parenteral nutrition-associated cholestasis (PNAC) is linked with the administration of soybean-based intravenous fat emulsion (IVFE). IVFE reduction (IFER) may be an effective management strategy for PNAC; however, long-term associated neurodevelopmental outcomes (NDOs) for infants undergoing IFER have not been measured previously. This single-institution, prospective study examined the risk for negative NDOs and key predictors of NDOs associated with IFER.

METHODS

Patients (2-5 years) treated with soybean-based IFER as neonates underwent NDO measurements, including Ages and Stages Questionnaires-3 (ASQ-3), Parents' Evaluations of Developmental Status (PEDS), and Behavior Assessment System for Children, Second Edition Preschool, Parent (BASC-2 PRS-P). The relationship between NDOs and predictive variables was evaluated.

RESULTS

A total of 25 children had a complete PEDS survey, and 17 were found to be "not at risk." The BASC-2 PRS-P evaluation (n = 18 patients) showed that all 4 composite domains fell within the normative developmental range, and 67%-89% of patients were observed to be "typically developing." For the primary outcome measure, ASQ-3, 82.4%-94.4% of patients were "not at risk." Logistical regression analyses were performed to examine risk factors contributing to negative NDOs. Of children completing all NDO studies, IFER-related variables (eg, development of essential fatty acid deficiency, duration of IFER, and mean IVFE dose) were not found to be predictors of adverse NDOs.

CONCLUSIONS

This study represents the first report of NDOs in pediatric patients treated with IFER. IFER-treated patients score within the normative range most of the time. IFER-related variables were not found to be associated with negative NDOs. The results set the stage for a larger, multicenter, prospective study.