Outcomes of preterm infants <29 weeks gestation over 10-year period in Canada: a cause for concern?

Identification of a myofibroblast differentiation program during neonatal lung development

Alveologenesis is the final stage of lung development in which the internal surface area of the lung is increased to facilitate efficient gas exchange in the mature organism. The first phase of alveologenesis involves the formation of septal ridges (secondary septae) and the second phase involves thinning of the alveolar septa. Within secondary septa, mesenchymal cells include a transient population of alveolar myofibroblasts (MyoFBs) and a stable but poorly described population of lipid-rich cells that have been referred to as lipofibroblasts or matrix fibroblasts (MatFBs). Using a unique Fgf18CreER lineage trace mouse line, cell sorting, single-cell RNA sequencing and primary cell culture, we have identified multiple subtypes of mesenchymal cells in the neonatal lung, including an immature progenitor cell that gives rise to mature MyoFB. We also show that the endogenous and targeted ROSA26 locus serves as a sensitive reporter for MyoFB maturation. These studies identify a MyoFB differentiation program that is distinct from other mesenchymal cell types and increases the known repertoire of mesenchymal cell types in the neonatal lung.

Long-Term Outcomes of Multiple versus a Single Course of Antenatal Steroids: A Systematic Review

Multiple courses versus a single course of antenatal corticosteroids (ACS) have been associated with mild respiratory benefits but also adverse outcomes like smaller head circumference and birth weight. Long-term effects warrant study. We systematically reviewed long-term outcomes (≥1 year) in both preterm and term birth after exposure to preterm multiple courses (including a rescue dose or course) versus a single course. We searched seven databases from January 2000 to October 2021. We included follow-up studies of randomized controlled trials (RCTs) and cohort studies with births occurring in/after the year 2000, given advances in perinatal care. Two reviewers assessed titles/abstracts, articles, quality, and outcomes including psychological disorders, neurodevelopment, and anthropometry. Six follow-up studies of three RCTs and two cohort studies (over 2,860 children total) met inclusion criteria. Among children born preterm, randomization to multiple courses versus a single course of ACS was not associated with adjusted beneficial or adverse neurodevelopmental/psychological or other outcomes, but data are scant after a rescue dose (120 and 139 children, respectively, low certainty) and nonexistent after a rescue course. For children born at term (i.e., 27% of the multiple courses of ACS 5-year follow-up study of 1,728 preterm/term born children), preterm randomization to multiple courses (at least one additional course) versus a single course was significantly associated with elevated odds of neurosensory impairment (adjusted odds ratio = 3.70, 95% confidence interval: 1.57-8.75; 212 and 247 children, respectively, moderate certainty). In this systematic review of long-term outcomes after multiple courses versus a single course of ACS, there were no significant benefits or risks regarding neurodevelopment in children born preterm but little data after one rescue dose and none after a rescue course. However, multiple courses (i.e., at least one additional course) should be considered cautiously: after term birth, there are no long-term benefits but neurosensory harms. KEY POINTS: · We systematically reviewed the long-term impact of multiple versus a single course of ACS.. · Long-term follow-up data were scant after a rescue dose and absent after one rescue course of ACS.. · In children born preterm, multiple courses of ACS were not associated with long-term benefits/harms.. · In children born at term, multiple courses of ACS were associated with neurosensory impairment.. · Preterm administration of multiple courses of ACS should be considered cautiously..

Identification of a myofibroblast differentiation program during neonatal lung development

Alveologenesis is the final stage of lung development in which the internal surface area of the lung is increased to facilitate efficient gas exchange in the mature organism. The first phase of alveologenesis involves the formation of septal ridges (secondary septae) and the second phase involves thinning of the alveolar septa. Within secondary septa, mesenchymal cells include a transient population of alveolar myofibroblasts (MyoFB) and a stable but poorly described population of lipid rich cells that have been referred to as lipofibroblasts or matrix fibroblasts (MatFB). Using a unique Fgf18CreER lineage trace mouse line, cell sorting, single cell RNA sequencing, and primary cell culture, we have identified multiple subtypes of mesenchymal cells in the neonatal lung, including an immature progenitor cell that gives rise to mature MyoFB. We also show that the endogenous and targeted ROSA26 locus serves as a sensitive reporter for MyoFB maturation. These studies identify a myofibroblast differentiation program that is distinct form other mesenchymal cells types and increases the known repertoire of mesenchymal cell types in the neonatal lung.

Survival and characteristics of retinopathy of prematurity in micro-premature infants

OBJECTIVE

To describe the risk and nature of retinopathy of prematurity (ROP) in micro-premature infants (≤26 weeks' gestational age [GA]).

METHODS

Retrospective analysis of prospectively collected data from infants born at 22-26 weeks' GA over a 5-year period.

RESULTS

A total of 502 infants were identified, of whom 414 survived to discharge (82.5%). The Vermont Oxford Network database documented clinical follow-up data and ROP outcomes for all 414 patients; complete ROP clinical records were available for 294 of the infants who survived (70.8%). Forty infants were born between 22 and 23 weeks' GA (group A, 13.6%), and 254 were born between 24 and 26 weeks' GA (group B, 86.4%). Survival for group A infants was worse than that of group B infants (66.2% vs 85.4%; p < 0.01). Survival of group A infants improved during the study period (R2 = 0.625). Overall, 59.9% of infants developed any ROP and 8.5% developed type 1 ROP. Group A infants were more likely to develop ROP (90.0% vs 48.6%; p < 0.01) and type 1 ROP (30.0% vs 5.1%; p < 0.01) than group B infants. Group A infants developed ROP at an earlier age (32 + 6 weeks vs 33 + 3 weeks; p = 0.02) and were more likely to have zone I disease on presentation (65.0% vs 20.5%; p < 0.01), but there was no difference in the corrected gestational age of peak severity of ROP (35 + 2 weeks vs 34 + 5 weeks; p = 0.36).

CONCLUSION

The most premature infants, born at 22-23 weeks' GA, develop ROP at an earlier age, are more likely to present with posterior disease, and have a high risk of disease requiring treatment.

Advances in neonatal cell therapies: Proceedings of the First Neonatal Cell Therapies Symposium (2022)

Despite considerable advances, there is a need to improve the outcomes of newborn infants, especially related to prematurity, encephalopathy and other conditions. In principle, cell therapies have the potential to protect, repair, or sometimes regenerate vital tissues; and improve or sustain organ function. In this review, we present highlights from the First Neonatal Cell Therapies Symposium (2022). Cells tested in preclinical and clinical studies include mesenchymal stromal cells from various sources, umbilical cord blood and cord tissue derived cells, and placental tissue and membrane derived cells. Overall, most preclinical studies suggest potential for benefit, but many of the cells tested were not adequately defined, and the optimal cell type, timing, frequency, cell dose or the most effective protocols for the targeted conditions is not known. There is as yet no clinical evidence for benefit, but several early phase clinical trials are now assessing safety in newborn babies. We discuss parental perspectives on their involvement in these trials, and lessons learnt from previous translational work of promising neonatal therapies. Finally, we make a call to the many research groups around the world working in this exciting yet complex field, to work together to make substantial and timely progress to address the knowledge gaps and move the field forward. IMPACT: Survival of preterm and sick newborn infants is improving, but they continue to be at high risk of many systemic and organ-specific complications. Cell therapies show promising results in preclinical models of various neonatal conditions and early phase clinical trials have been completed or underway. Progress on the potential utility of cell therapies for neonatal conditions, parental perspectives and translational aspects are discussed in this paper.

Trends, Characteristic, and Outcomes of Preterm Infants Who Received Postnatal Corticosteroid: A Cohort Study from 7 High-Income Countries

INTRODUCTION

Our objective was to evaluate the temporal trend of systemic postnatal steroid (PNS) receipt in infants of 24-28 weeks' gestational age, identify characteristics associated with PNS receipt, and correlate PNS receipt with the incidence of bronchopulmonary dysplasia (BPD) and BPD/death from an international cohort included in the iNeo network.

METHODS

We conducted a retrospective study using data from 2010 to 2018 from seven international networks participating in iNeo (Canada, Finland, Israel, Japan, Spain, Sweden, and Switzerland). Neonates of 24 and 28 weeks' gestational age who survived 7 days and who received PNS were included. We assessed temporal trend of rates of systemic PNS receipt and BPD/death.

RESULTS

A total of 47,401 neonates were included. The mean (SD) gestational age was 26.4 (1.3) weeks and birth weight was 915 (238) g. The PNS receipt rate was 21% (12-28% across networks) and increased over the years (18% in 2010 to 26% in 2018; p < 0.01). The BPD rate was 39% (28-44% across networks) and remained unchanged over the years (35.2% in 2010 to 35.0% in 2018). Lower gestation, male sex, small for gestational age status, and presence of persistent ductus arteriosus (PDA) were associated with higher rates of PNS receipt, BPD, and BPD/death.

CONCLUSION

The use of PNS in extremely preterm neonates increased, but there was no correlation between increased use and the BPD rate. Research is needed to determine the optimal timing, dose, and indication for PNS use in preterm neonates.

Stem cell therapies for neonatal lung diseases: Are we there yet?

Lung diseases are a main cause of mortality and morbidity in neonates. Despite major breakthroughs, therapies remain supportive and, in some instances, contribute to lung injury. Because the neonatal lung is still developing, the ideal therapy should be capable of preventing/repairing lung injury while at the same time, promoting lung growth. Cell-based therapies hold high hopes based on laboratory experiments in animal models of neonatal lung injury. Mesenchymal stromal cells and amnion epithelial cells are now in early phase clinical trials to test the feasibility, safety and early signs of efficacy in preterm infants at risk of developing bronchopulmonary dysplasia. Other cell-based therapies are being explored in experimental models of congenital diaphragmatic hernia and alveolar capillary dysplasia. This review will summarize current evidence that has lead to the clinical translation of cell-based therapies and highlights controversies and the numerous questions that remain to be addressed to harness the putative repair potential of cell-based therapies.

Iron supplementation and the risk of bronchopulmonary dysplasia in extremely low gestational age newborns

BACKGROUND

The aim of this study was to determine the relationship between iron exposure and the development of bronchopulmonary dysplasia (BPD).

METHODS

A secondary analysis of the PENUT Trial dataset was conducted. The primary outcome was BPD at 36 weeks gestational age and primary exposures of interest were cumulative iron exposures in the first 28 days and through 36 weeks' gestation. Descriptive statistics were calculated for study cohort characteristics with analysis adjusted for the factors used to stratify randomization.

RESULTS

Of the 941 patients, 821 (87.2%) survived to BPD evaluation at 36 weeks, with 332 (40.4%) diagnosed with BPD. The median cohort gestational age was 26 weeks and birth weight 810 g. In the first 28 days, 76% of infants received enteral iron and 55% parenteral iron. The median supplemental cumulative enteral and parenteral iron intakes at 28 days were 58.5 and 3.1 mg/kg, respectively, and through 36 weeks' 235.8 and 3.56 mg/kg, respectively. We found lower volume of red blood cell transfusions in the first 28 days after birth and higher enteral iron exposure in the first 28 days after birth to be associated with lower rates of BPD.

CONCLUSIONS

We find no support for an increased risk of BPD with iron supplementation.

TRIAL REGISTRATION NUMBER

NCT01378273. https://clinicaltrials.gov/ct2/show/NCT01378273 IMPACT: Prior studies and biologic plausibility raise the possibility that iron administration could contribute to the pathophysiology of oxidant-induced lung injury and thus bronchopulmonary dysplasia in preterm infants. For 24-27-week premature infants, this study finds no association between total cumulative enteral iron supplementation at either 28-day or 36-week postmenstrual age and the risk for developing bronchopulmonary dysplasia.

Who's afraid of the X? Incorporating the X and Y chromosomes into the analysis of DNA methylation array data

BACKGROUND

Many human disease phenotypes manifest differently by sex, making the development of methods for incorporating X and Y-chromosome data into analyses vital. Unfortunately, X and Y chromosome data are frequently excluded from large-scale analyses of the human genome and epigenome due to analytical complexity associated with sex chromosome dosage differences between XX and XY individuals, and the impact of X-chromosome inactivation (XCI) on the epigenome. As such, little attention has been given to considering the methods by which sex chromosome data may be included in analyses of DNA methylation (DNAme) array data.

RESULTS

With Illumina Infinium HumanMethylation450 DNAme array data from 634 placental samples, we investigated the effects of probe filtering, normalization, and batch correction on DNAme data from the X and Y chromosomes. Processing steps were evaluated in both mixed-sex and sex-stratified subsets of the analysis cohort to identify whether including both sexes impacted processing results. We found that identification of probes that have a high detection p-value, or that are non-variable, should be performed in sex-stratified data subsets to avoid over- and under-estimation of the quantity of probes eligible for removal, respectively. All normalization techniques investigated returned X and Y DNAme data that were highly correlated with the raw data from the same samples. We found no difference in batch correction results after application to mixed-sex or sex-stratified cohorts. Additionally, we identify two analytical methods suitable for XY chromosome data, the choice between which should be guided by the research question of interest, and we performed a proof-of-concept analysis studying differential DNAme on the X and Y chromosome in the context of placental acute chorioamnionitis. Finally, we provide an annotation of probe types that may be desirable to filter in X and Y chromosome analyses, including probes in repetitive elements, the X-transposed region, and cancer-testis gene promoters.

CONCLUSION

While there may be no single "best" approach for analyzing DNAme array data from the X and Y chromosome, analysts must consider key factors during processing and analysis of sex chromosome data to accommodate the underlying biology of these chromosomes, and the technical limitations of DNA methylation arrays.

Associations between maternal residential rurality and maternal health, access to care, and very low birthweight infant outcomes

OBJECTIVE

Infant mortality is increased in isolated rural areas. This study compares prenatal factors, access to care, and health outcomes for very-low birthweight (VLBW) infants by degree of maternal residential rurality.

METHODS

This descriptive population-based retrospective cohort study used the California Perinatal Quality Care Collaborative registry to study VLBW infants. Rurality was assigned as urban, large rural, and small rural/isolated using the Rural Urban Commuting Area codes. We used hierarchical random effect models to test the association of rurality with survival without major morbidity.

RESULTS

The study included 38 614 dyads. VLBW survival without major morbidity decreased with increasing rurality and the relationship remained significant for small rural/isolated areas (OR 0.79, p = 0.03) after adjustment. Birth weight, gestational age, and infant sex were similar across geographic groups.

CONCLUSION

A rural urban disparity exists for VLBW survival without major morbidity. Our findings generate hypotheses about factors that may be driving these disparities.

Timing of Systemic Steroids and Neurodevelopmental Outcomes in Infants < 29 Weeks Gestation

Objective: To determine the association between postnatal age (PNA) at first administration of systemic postnatal steroids (sPNS) for bronchopulmonary dysplasia (BPD) and mortality or significant neurodevelopmental impairment (sNDI) at 18−24 months corrected age (CA) in infants < 29 weeks’ gestation. Methods: Data from the Canadian Neonatal Network and Canadian Neonatal Follow-up Network databases were used to conduct this retrospective cohort study. Infants exposed to sPNS for BPD after the 1st week of age were included and categorized into 8 groups based on the postnatal week of the exposure. The primary outcome was a composite of mortality or sNDI. A multivariable logistic regression model adjusting for potential confounders was used to determine the association between the sPNS and ND outcomes. Results: Of the 10,448 eligible infants, follow-up data were available for 6200 (59.3%) infants. The proportion of infants at first sPNS administration was: 8%, 17.5%, 23.1%, 18.7%, 12.6%, 8.3%, 5.8%, and 6% in the 2nd, 3rd, 4th, 5th, 6th, 7th, 8−9th, and ≥10th week of PNA respectively. No significant association between the timing of sPNS administration and the composite outcome of mortality or sNDI was observed. The odds of sNDI and Bayley-III motor composite < 70 increased by 1.5% (95% CI 0.4, 2.9%) and 2.6% (95% CI 0.9, 4.4%), respectively, with each one-week delay in the age of initiation of sPNS. Conclusions: No significant association was observed between the composite outcome of mortality or sNDI and PNA of sPNS. Among survivors, each week’s delay in initiation of sPNS may increase the odds of sNDI and motor delay.

Short term outcomes of extremely low birth weight infants from a multicenter cohort study in Guangdong of China

With the increase in extremely low birth weight (ELBW) infants, their outcome attracted worldwide attention. However, in China, the related studies are rare. The hospitalized records of ELBW infants discharged from twenty-six neonatal intensive care units in Guangdong Province of China during 2008-2017 were analyzed. A total of 2575 ELBW infants were enrolled and the overall survival rate was 55.11%. From 2008 to 2017, the number of ELBW infants increased rapidly from 91 to 466, and the survival rate improved steadily from 41.76% to 62.02%. Increased survival is closely related to birth weight (BW), regional economic development, and specialized hospital. The incidence of complications was neonatal respiratory distress syndrome (85.2%), oxygen dependency at 28 days (63.7%), retinopathy of prematurity (39.3%), intraventricular hemorrhage (29.4%), necrotizing enterocolitis (12.0%), and periventricular leukomalacia (8.0%). Among the 1156 nonsurvivors, 90.0% of infants died during the neonatal period (≤ 28 days). A total of 768 ELBW infants died after treatment withdrawal, for reasons of economic and/or poor outcome. The number of ELBW infants is increasing in Guangdong Province of China, and the overall survival rate is improving steadily.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles for Neonatal Lung Disease: Tiny Particles, Major Promise, Rigorous Requirements for Clinical Translation

Extreme preterm birth disrupts late lung development and puts newborns at risk of developing chronic lung disease, known as bronchopulmonary dysplasia (BPD). BPD can be associated with life-long complications, and currently no effective treatment is available. Cell therapies are entering the clinics to curb complications of extreme preterm birth with several clinical trials testing the feasibility, safety and efficacy of mesenchymal stromal cells (MSCs). The therapeutic effect of MSCs is contained in their secretome, and nanosized membranous structures released by the MSCs, known as extracellular vesicles (EVs), have been shown to be the therapeutic vectors. Driven by this discovery, the efficacy of EV-based therapy is currently being explored in models of BPD. EVs derived from MSCs, contain a rich cargo of anti-inflammatory and pro-angiogenic molecules, making them suitable candidates to treat multifactorial diseases such as BPD. Here, we review the state-of-the-art of preclinical studies involving MSC-derived EVs in models of BPD and highlight technical and regulatory challenges that need to be addressed before clinical translation. In addition, we aim at increasing awareness regarding the importance of rigorous reporting of experimental details of EV experiments and to increase the outreach of the current established guidelines amongst researchers in the BPD field.

Physiological aspects of cardiopulmonary dysanapsis on exercise in adults born preterm

Progressive improvements in perinatal care and respiratory management of preterm infants have resulted in increased survival of newborns of extremely low gestational age over the past few decades. However, the incidence of bronchopulmonary dysplasia, the chronic lung disease after preterm birth, has not changed. Studies of the long-term follow-up of adults born preterm have shown persistent abnormalities of respiratory, cardiovascular and cardiopulmonary function, possibly leading to a lower exercise capacity. The underlying causes of these abnormalities are incompletely known, but we hypothesize that dysanapsis, i.e. discordant growth and development, in the respiratory and cardiovascular systems is a central structural feature that leads to a lower exercise capacity in young adults born preterm than those born at term. We discuss how the hypothesized system dysanapsis underscores the observed respiratory, cardiovascular and cardiopulmonary limitations. Specifically, adults born preterm have: (1) normal lung volumes but smaller airways, which causes expiratory airflow limitation and abnormal respiratory mechanics but without impacts on pulmonary gas exchange efficiency; (2) normal total cardiac size but smaller cardiac chambers; and (3) in some cases, evidence of pulmonary hypertension, particularly during exercise, suggesting a reduced pulmonary vascular capacity despite reduced cardiac output. We speculate that these underlying developmental abnormalities may accelerate the normal age-associated decline in exercise capacity, via an accelerated decline in respiratory, cardiovascular and cardiopulmonary function. Finally, we suggest areas of future research, especially the need for longitudinal and interventional studies from infancy into adulthood to better understand how preterm birth alters exercise capacity across the lifespan.

Thrombospondin-1 Plays a Major Pathogenic Role in Experimental and Human Bronchopulmonary Dysplasia

RATIONALE

Extremely preterm infants develop bronchopulmonary dysplasia (BPD), a chronic lung injury that lacks effective treatment. Thrombospondin-1 is an anti-angiogenic protein that activates TGF-β1, a cytokine strongly linked to both experimental and human BPD.

OBJECTIVES

1) To examine effects of inhibiting thrombospondin-1-mediated TGF-β1 activation (LSKL) in neonatal rats with bleomycin-induced lung injury, 2) To examine effects of a thrombospondin-1-mimic (ABT-510) on lung morphology, and 3) To determine whether thrombospondin-1 and related signaling peptides are increased in lungs of human preterm infants at risk for BPD.

METHODS

From postnatal days 1-14, rat pups received daily i.p. bleomycin (1 mg/kg) or vehicle combined with daily s.c. LSKL (20 mg/kg) or vehicle. Separate animals were treated with vehicle or ABT-510 (30 mg/kg/d). Paraffin-embedded lung tissues from 47 autopsies (controls; death <28 days, n=30 and BPD at risk; death ≥28 days, n=17) performed on infants born <29 completed weeks' gestation were semi-quantified for injury markers (collagen, macrophages, 3-nitrotyrosine), thrombospondin-1 and TGF-β1.

MEASUREMENTS AND MAIN RESULTS

Bleomycin or ABT-510 increased lung TGF-β1 activity and macrophage influx, caused pulmonary hypertension and led to alveolar and microvascular hypoplasia. Treatment with LSKL partially prevented abnormal lung morphology secondary to bleomycin. Lungs from human infants at-risk for BPD had increased contents of thrombospondin-1 and TGF-β1 when compared to controls. TGF-β1 content correlated with markers of lung injury.

CONCLUSIONS

Thrombospondin-1 inhibits alveologenesis in neonatal rats, in part via up-regulated activity of TGF-β1. Observations in human lung suggest a similar pathogenic role for thrombospondin-1 in infants at-risk for BPD.

Predictors of long-term neurodevelopmental outcomes of children born extremely preterm

Children born extremely preterm (<28 weeks' gestation) are at high risk of a range of adverse neurodevelopmental outcomes in later childhood compared with their peers born at term, including cognitive, motor, and behavioral difficulties. These difficulties can be associated with poorer academic achievement and health outcomes at school age. In this review, we discuss several predictors in the newborn period of early childhood neurodevelopmental outcomes including perinatal risk factors, neuroimaging findings and neurobehavioral assessments, along with social and environmental influences for children born extremely preterm. Given the complexity of predicting long-term outcomes in children born extremely preterm, we recommend multi-disciplinary teams in clinical practice to assist in determining an individual child's risk for adverse long-term outcomes and need for referral to targeted intervention, based upon their risk.

The Intertemporal Role of Respiratory Support in Improving Neonatal Outcomes: A Narrative Review

Defining improvements in healthcare can be challenging due to the need to assess multiple outcomes and measures. In neonates, although progress in respiratory support has been a key factor in improving survival, the same degree of improvement has not been documented in certain outcomes, such as bronchopulmonary dysplasia. By exploring the evolution of neonatal respiratory care over the last 60 years, this review highlights not only the scientific advances that occurred with the application of invasive mechanical ventilation but also the weakness of the existing knowledge. The contributing role of non-invasive ventilation and less-invasive surfactant administration methods as well as of certain pharmacological therapies is also discussed. Moreover, we analyze the cost-benefit of neonatal care-respiratory support and present future challenges and perspectives.

Impact of very preterm birth and post-discharge growth on cardiometabolic outcomes at school age: a retrospective cohort study

Background

Adverse metabolic outcomes later in life have been reported among children or young adults who were born as preterm infants. This study was conducted to examine the impact of very preterm/very low birth weight (VP/VLBW) birth and subsequent growth after hospital discharge on cardiometabolic outcomes such as insulin resistance, fasting glucose, and systolic and diastolic blood pressure (BP) among children at 6–8 years of age.

Methods

This retrospective cohort study included children aged 6–8 years and compared those who were born at < 32 weeks of gestation or weighing < 1,500 g at birth (n = 60) with those born at term (n = 110). Body size, fat mass, BP, glucose, insulin, leptin, adiponectin, and lipid profiles were measured. Weight-for-age z-score changes between discharge and early school-age period were also calculated, and factors associated with BP, fasting glucose, and insulin resistance were analyzed.

Results

Children who were born VP/VLBW had significantly lower fat masses, higher systolic BP and diastolic BP, and significantly higher values of fasting glucose, insulin, and homeostatic model assessment of insulin resistance (HOMA-IR), compared to children born at term. VP/VLBW was correlated with HOMA-IR and BPs after adjusting for various factors, including fat mass index and weight-for-age z-score changes. Weight-for-age z-score changes were associated with HOMA-IR, but not with BPs.

Conclusions

Although children aged 6–8 years who were born VP/VLBW showed significantly lower weight and fat mass, they had significantly higher BPs, fasting glucose, HOMA-IR, and leptin levels. The associations of VP/VLBW with cardiometabolic factors were independent of fat mass and weight gain velocity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02851-5.

Morbidity and respiratory outcomes in infants requiring tracheostomy for severe bronchopulmonary dysplasia

OBJECTIVE

The decision for tracheostomy for bronchopulmonary dysplasia (BPD) is highly variable and often dictated by local practice. We aimed to characterize morbidity, mortality, and respiratory outcomes in preterm infants undergoing tracheostomy for severe BPD.

STUDY DESIGN

We retrospectively reviewed a single-center 4-year cohort of all infants born <33 weeks gestational age (GA) that required tracheostomy due to severe BPD. Indications for tracheostomy apart from BPD were excluded. Demographic information, comorbidities, respiratory management, age at tracheostomy, post-discharge respiratory outcomes, and survival were examined up to at least 5 years of age.

RESULTS

At a mean corrected GA of 43.3 weeks, 49 preterm infants with severe BPD required tracheostomy. Forty-six infants (94%) had long-term follow-up. Compared to survivors, the 12 (26.1%) infants that died were significantly more likely to be small for gestational age (SGA) or require treatment for pulmonary hypertension. GA, birth weight, sex, antenatal corticosteroid exposure, need for patent ductus arteriosus ligation, and magnitude of respiratory support at tracheostomy placement were not associated with mortality. At the latest follow-up, 97% were liberated from mechanical ventilation and 79% decannulated. Morbidities of the upper airway were common, and 13/27 (47%) decannulated infants had required airway reconstruction.

CONCLUSION

Preterm infants undergoing tracheostomy experienced significant mortality, particularly those who were SGA or had pulmonary hypertension. However, by 5 years of age, most infants liberalized from mechanical ventilation and decannulated. Magnitude of respiratory support at time of tracheostomy was not associated with mortality and should not deter intervention. Nearly half of patients required airway reconstruction before decannulation.

Fluid status in the first 10 days of life and death/bronchopulmonary dysplasia among preterm infants

OBJECTIVE

To investigate the association between fluid and sodium status in the first 10 postnatal days and death/bronchopulmonary dysplasia (BPD) among infants born <29 weeks' gestation.

STUDY DESIGN

Single center retrospective cohort study (2015-2018) of infants born 23-28 weeks'. Three exposure variables were evaluated over the first 10 postnatal days: cumulative fluid balance (CFB), median serum sodium concentration, and maximum percentage weight loss. Primary outcome was death and/or BPD. Multivariable logistic regression adjusting for patient covariates was used to assess the association between exposure variables and outcomes.

RESULTS

Of 191 infants included, 98 (51%) had death/BPD. Only CFB differed significantly between BPD-free survivors and infants with death/BPD: 4.71 dL/kg (IQR 4.10-5.12) vs 5.11 dL/kg (IQR 4.47-6.07; p < 0.001). In adjusted analyses, we found an association between higher CFB and higher odds of death/BPD (AOR 1.56, 95% CI 1.11-2.25). This was mainly due to the association of CFB with BPD (AOR 1.60, 95% CI 1.12-2.35), rather than with death (AOR 1.08, 95% CI 0.54-2.30).

CONCLUSION

Among preterm infants, a higher CFB in the first 10 days after delivery is associated with higher odds of death/BPD.

IMPACT

Previous studies suggest that postnatal fluid status influences survival and respiratory function in neonates. Fluid balance, serum sodium concentration, and daily weight changes are commonly used as fluid status indicators in neonates. We found that higher cumulative fluid balance in the first 10 days of life was associated with higher odds of death/bronchopulmonary dysplasia in neonates born <29 weeks. Monitoring of postnatal fluid balance may be an appropriate non-invasive strategy to favor survival without bronchopulmonary dysplasia. We developed a cumulative fluid balance chart with corresponding thresholds on each day to help design future trials and guide clinicians in fluid management.

Retinopathy prematurity: a systematic review and meta-analysis study based on neonatal and maternal risk factors

BACKGROUND

Retinopathy of prematurity is the abnormal development of retinal arteries in preterm neonates less than 32 weeks and weighing 1500 g, and less, which can lead to visual impairment during life and blindness. This study aims to investigate the relationship between some clinical characteristics of neonates and mothers with Retinopathy of prematurity in the world via a systematic review and meta-analysis.

MATERIALS AND METHODS

The present study is a systematic review and meta-analysis on the relationship between maternal and neonatal clinical variables with Retinopathy of prematurity in the world from the beginning of 2000 to the end of 2020. Accordingly, all English articles published on the topic were searched in scientific databases of Web of Science, PubMed, Google Scholar, Science Direct, and Scopus. The articles were searched independently by two researchers. Statistical analysis of data was performed using fixed and random effects model statistical tests in the meta-analysis, Cochran, meta-regression, I² index, Funnel plot, and Begg's by STATA software program, version 14.

RESULT

A total of 191 studies with a sample size of 140,921 persons were including in the meta-analysis. Accordingly, Preterm delivery ≤28 weeks (OR:6.3, 95% CI:4.9-8.1), Birth Weight ≤1000 g (OR:5.8, 95% CI:4.8-6.8), Birth Weight ≤1500 g (OR:4.8, 95% CI:3.8-6.1), PROM (OR:1.2, 95% CI:1.0-1.4), induced fertility (OR:1.9, 95% CI:1.1-3.0) and Chorioamnionitis (OR:1.5, 95% CI:1.0-2.2) There was a statistically significant association with retinopathy.

CONCLUSION

Based on the results of the present meta-analysis, the risk of retinopathy of prematurity in neonates born at 28 weeks and less, LBW (weight 1500 g and less), neonatal hypotension, chorioamnionitis, and induced fertility increases.

Mortality and Morbidity of Infants Born Extremely Preterm at Tertiary Medical Centers in China From 2010 to 2019

IMPORTANCE

Extreme prematurity is associated with a substantial burden on health care systems worldwide. However, little is known about the prognosis of infants born extremely preterm in developing countries, such as China.

OBJECTIVE

To describe survival and major morbidity among infants born extremely preterm in China over the past decade.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study was conducted from January 1, 2010, through December 31, 2019. Included individuals were infants with gestational age less than 28 weeks discharged from 1 of 68 neonatal intensive care units located in 31 provinces in China. Data were analyzed from August through October 2020.

EXPOSURE

Extremely preterm birth.

MAIN OUTCOMES AND MEASURES

Survival to discharge and major morbidity (ie, bronchopulmonary dysplasia, grades III-IV intraventricular hemorrhage, white matter injury, stage II-III necrotizing enterocolitis, sepsis, or severe retinopathy of prematurity) were measured.

RESULTS

Among 8514 eligible infants, 5295 (62.2%) were male and 116 infants (2.0%) were small for gestational age (SGA). Overall, 5302 infants (62.3%) survived to discharge. The survival rate was 1 of 21 infants (4.8%) at 22 weeks, 13 of 71 infants (18.3%) at 23 weeks, 144 of 408 infants (35.3%) at 24 weeks, 480 of 987 infants (48.6%) at 25 weeks, 1423 of 2331 infants (61.0%) at 26 weeks, and 3241 of 4692 infants (69.1%) at 27 weeks. Survival increased from 136 of 241 infants (56.4%; 95% CI, 50.1%-62.7%) in 2010 to 1110 of 1633 infants (68.0%; 95% CI, 65.7%-70.2%) in 2019 for infants born at 24 to 27 weeks (mean difference, 11.5%; 95% CI, 4.9%-18.2%; P < .001), without a significant change for infants born at less than 24 weeks. Major morbidity was found in 5999 of 8281 infants overall, for a rate of 72.4%, which increased from 116 of 223 infants (52.0%; 95% CI, 45.4%-58.6%) to 1363 of 1656 infants (82.3%; 95% CI, 80.5%-84.1%) from 2010 to 2019 (mean difference, 30.3%; 95% CI, 23.5%-37.1%, P < .001). Regional variations in survival were identified, with an almost 2-fold increase (1.94-fold; 95% CI, 1.66-2.27; P < .001) from 188 of 474 infants (39.7%) in northwest China to 887 of 1153 infants (76.9%) in north China. Gestational age (adjusted risk ratio [aRR], 1.084; 95% CI, 1.063-1.105; P < .001), birth weight (aRR, 1.028; 95% CI, 1.020-1.036; P < .001), premature rupture of membranes (aRR, 1.025; 95% CI, 1.002-1.048; P = .03), and antenatal steroids (aRR, 1.029; 95% CI, 1.004-1.055; P = .02) were associated with improved survival, while being born SGA (aRR, 0.801; 95% CI, 0.679-0.945; P = .01), being male (aRR, 0.975; 95% CI, 0.954-0.997; P = .02), multiple birth (aRR, 0.955; 95% CI, 0.929-0.982; P = .001), having a mother with gestational diabetes (aRR, 0.946; 95% CI, 0.913-0.981; P = .002), and low Apgar score (aRR, 0.951; 95% CI, 0.925-0.977; P < .001) were found to be risk factors associated with decreased chances of survival.

CONCLUSIONS AND RELEVANCE

This study found that infants born extremely preterm were at increased risk of mortality and morbidity in China, with a survival rate that improved over time and a major morbidity rate that increased. These findings suggest that more active and effective treatment strategies are needed, especially for infants born at gestational age 25 to 27 weeks.

Survival and causes of death in extremely preterm infants in the Netherlands

OBJECTIVE

In the Netherlands, the threshold for offering active treatment for spontaneous birth was lowered from 25⁺⁰ to 24⁺⁰ weeks' gestation in 2010. This study aimed to evaluate the impact of guideline implementation on survival and causes and timing of death in the years following implementation.

DESIGN

National cohort study, using data from the Netherlands Perinatal Registry.

PATIENTS

The study population included all 3312 stillborn and live born infants with a gestational age (GA) between 24^0/7 and 26^6/7 weeks born between January 2011 and December 2017. Infants with the same GA born between January 2007 and December 2009 (N=1400) were used as the reference group.

MAIN OUTCOME MEASURES

Survival to discharge, as well as cause and timing of death.

RESULTS

After guideline implementation, there was a significant increase in neonatal intensive care unit (NICU) admission rate for live born infants born at 24 weeks' GA (27%-69%, p<0.001), resulting in increased survival to discharge in 24-week live born infants (13%-34%, p<0.001). Top three causes of in-hospital mortality were necrotising enterocolitis (28%), respiratory distress syndrome (19%) and intraventricular haemorrhage (17%). A significant decrease in cause of death either complicated or caused by respiratory insufficiency was seen over time (34% in 2011-2014 to 23% in 2015-2017, p=0.006).

CONCLUSIONS

Implementation of the 2010 guideline resulted as expected in increased NICU admissions rate and postnatal survival of infants born at 24 weeks' GA. In the years after implementation, a shift in cause of death was seen from respiratory insufficiency towards necrotising enterocolitis and sepsis.

A systematic review of reports of quality improvement for bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the most common morbidity of preterm infants, and its incidence has not responded to research and intervention efforts to the same degree as other major morbidities associated with prematurity. The complexity of neonatal respiratory care as well as persistent inter-institutional variability in BPD rates suggest that BPD may be amenable to quality improvement (QI) efforts. We present a systematic review of QI for BPD in preterm infants. We identified 22 reports from single centers and seven from collaborative efforts published over the past two decades. In almost all of the reports, respiratory QI interventions successfully reduced BPD or other key respiratory measures, particularly for infants with birth weight over 1000 g. Several themes and lessons from existing reports may help inform future efforts in both research and QI to impact the burden of BPD.

Micro-premature infants in New Jersey show improved mortality and morbidity from 2000-2018

BACKGROUND

Micro-premature newborns, gestational age (GA) ≤ 25 weeks, have high rates of mortality and morbidity. Literature has shown improving outcomes for extremely low gestational age newborns (ELGANs) GA ≤ 29 weeks, but few studies have addressed outcomes of ELGANs ≤ 25 weeks.

OBJECTIVE

To evaluate the trends in outcomes for ELGANs born in New Jersey, from 2000 to 2018 and to compare two subgroups: GA 23 to 25 weeks (E1) and GA 26 to 29 weeks (E2).

METHODS

Thirteen NICUs in NJ submitted de-identified data. Outcomes for mortality and morbidity were calculated.

RESULTS

Data from 12,707 infants represents the majority of ELGANs born in NJ from 2000 to 2018. There were 3,957 in the E1 group and 8,750 in the E2 group. Mortality decreased significantly in both groups; E1, 43.2% to 30.2% and E2, 7.6% to 4.5% over the 19 years. The decline in E1 was significantly greater than in E2. Most morbidities also showed significant improvement over time in both groups. Survival without morbidity increased from 14.5% to 30.7% in E1s and 47.2% to 69.9% in E2s. Similar findings held for 501-750 and 751-1000g birth weight strata.

CONCLUSIONS

Significant declines in both mortality and morbidity have occurred in ELGANs over the last two decades. These rates of improvements for the more immature ELGANs of GA 230 to 256 weeks were greater than for the more mature group in several outcomes. While the rates of morbidity and mortality remain high, these results validate current efforts to support the micro-premature newborn.

Long-Term Outcomes of Bronchopulmonary Dysplasia Under Two Different Diagnostic Criteria: A Retrospective Cohort Study at a Chinese Tertiary Center

Unlike other complications among very low birth weight infants (VLBW), the incidence of bronchopulmonary dysplasia (BPD) has not decreased substantially, partly because of the different definitions of BPD applied by different researchers. In this retrospective cohort study, we aimed to compare the 2018 revised definition and the 2001 consensus definition of BPD proposed by the National Institute of Child Health and Human Development (NICHD), as well as to identify which definition better predicts severe respiratory morbidities or death. We included 417 infants born at a gestational age <32 weeks and classified them as having BPD or without BPD based on the two definitions, with a final follow-up at 18-24 months. We performed between-group comparisons of death and respiratory outcomes. Statistical analyses were performed using descriptive statistics, comparative tests, and receiver operating characteristic curves. The mean ± standard deviation gestational age and birth weight of the 417 eligible infants were 29.1 ± 1.4 weeks and 1186.6 ± 197.8 g, respectively. Among the included infants, five and three infants died before and after 36 weeks of post-menstrual age (PMA), respectively, with 68 and 344 infants evaluated at discharge and 36 weeks' PMA, respectively. We diagnosed 163 (39.1%) and 70 (16.8%) infants with BPD according to the 2001 and 2018 NICHD definitions, respectively. The 2001 NICHD definition displayed a higher sensitivity (0.60 vs. 0.28), better negative predictive value (0.89 vs. 0.85), and larger area under the receiver operating characteristic curve (0.66 vs. 0.57), but a lower specificity (0.65 vs. 0.87) and worse positive predictive value (0.26 vs. 0.31), than the 2018 definition for serious respiratory morbidity or mortality at a corrected age of 18-24 months. Compared with the 2018 NICHD definition of BPD, the 2001 NICHD consensus definition may result in more cases of false-positive or unclassified severity. However, it may be a better indicator of severe respiratory morbidities or death during the first 18-24 months. Nevertheless, there is a need for future studies to assess the validity of the new diagnostic criteria.

'What's in a name?'-The effective promotion of brain health in preterm babies

The achievement of optimal brain health in very preterm babies is a challenge for modern neonatology. There has been limited success in this area of concern despite improvements in other neonatal outcomes. The barriers to progress are (a) the language and definitions that clinicians and scientists use to describe outcomes, (b) our representation of causation, and (c) the rigour with which we apply quality improvement science. Quality improvement science requires clear, relevant, and discriminating language to explain aims, drivers, processes, outcomes, interventions, and definitions. To date, clinical guidelines and research publications have not addressed prevailing flaws in language, causation, and definition. The persisting flaws have restricted identification of quality improvement opportunities and limited the impact of quality improvement efforts. Our community of neonatal caregivers and researchers needs a new and comprehensive approach to language, causation, and implementation science in order to address brain health in very preterm babies.

Phenotypes of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is the most common chronic morbidity in preterm infants. In the absence of effective interventions, BPD is currently a major therapeutic challenge. Several risk factors are known for this multifactorial disease that results in disrupted lung development. Inflammation plays an important role and leads to persistent airway and pulmonary vascular disease. Since corticosteroids are potent anti-inflammatory agents, postnatal corticosteroids have been used widely for BPD prevention and treatment. However, the clinical responses vary to a great degree across individuals, and steroid-related complications remain major concerns. Emerging studies on the molecular mechanism of lung alveolarization during inflammatory stress will elucidate the complicated pathway and help discover novel therapeutic targets. Moreover, with the advances in metabolomics, there are new opportunities to identify biomarkers for early diagnosis and prognosis prediction of BPD. Pharmacometabolomics is another novel field aiming to identify the metabolomic changes before and after a specific drug treatment. Through this "metabolic signature," a more precise treatment may be developed, thereby avoiding unnecessary drug exposure in non-responders. In the future, more clinical, genetic, and translational studies would be required to improve the classification of BPD phenotypes and achieve individualized care to enhance the respiratory outcomes in preterm infants.

Respiratory and cardiopulmonary limitations to aerobic exercise capacity in adults born preterm

Adults born preterm, regardless of whether they develop bronchopulmonary dysplasia, have underdeveloped respiratory and cardiopulmonary systems. The resulting impaired respiratory and cardiopulmonary systems are inadequate for the challenges imposed by aerobic exercise, which is exacerbated by the presence of bronchopulmonary dysplasia. Thus the respiratory and cardiopulmonary systems of these preterm individuals may be the most influential contributors to the significantly lower aerobic exercise capacity compared with their term born counterparts. The precise underlying cause(s) of the lower aerobic exercise capacity in adults born preterm is not entirely known but could be a number of interrelated parameters including mechanical ventilatory constraints, impaired pulmonary gas exchange efficiency, and excessive cardiopulmonary pressures. Likewise, additional aspects, such as impaired cardiovascular function and altered muscle bioenergetics, may play additional roles in limiting aerobic exercise capacity. Whether or not all or some of these aspects are present in adults born preterm and precisely how they may contribute to the lower aerobic exercise capacity are only beginning to be systematically explored. The purpose of this mini-review is to outline what is currently known about the respiratory and cardiopulmonary limitations during exercise in this population and to identify key areas where additional knowledge will help to advance this area. Additionally, where possible, we highlight the similarities and differences between obstructive lung disease resulting from preterm birth and chronic obstructive pulmonary disease (COPD) as the physiology and pathophysiology of these two forms of obstructive lung disease may not be identical.

L’administration postnatale de corticostéroïdes pour prévenir ou traiter la dysplasie bronchopulmonaire chez les nouveau-nés prématurés

Les corticostéroïdes ont longtemps été administrés pendant la période postnatale pour prévenir et traiter la dysplasie bronchopulmonaire (DBP), une cause importante de morbidité et de mortalité chez les nouveau-nés prématurés. L’administration préventive de dexaméthasone pendant la première semaine de vie est liée à une augmentation du risque de paralysie cérébrale, et l’administration précoce de corticostéroïdes inhalés semble être associée à une hausse du risque de mortalité. À l’heure actuelle, aucune de ces deux approches n’est recommandée pour prévenir la DBP. Selon de nouvelles données probantes, un traitement prophylactique d’hydrocortisone à des doses physiologiques, entrepris avant 48 heures de vie sans ajout d’indométacine, améliore la survie sans DBP, et n’a pas d’effets neurodéveloppementaux indésirables à l’âge de deux ans. Les cliniciens peuvent envisager ce traitement pour les nouveau-nés les plus à risque de DBP. Il n’est pas recommandé d’entreprendre un traitement systématique de dexaméthasone pour tous les nouveau-nés sous assistance respiratoire, mais après la première semaine de vie, les cliniciens peuvent envisager un court traitement de dexaméthasone à faible dose (0,15 mg/kg/jour à 0,2 mg/kg/jour) pour certains nouveau-nés à haut risque de DBP ou atteints d’une DBP évolutive. Aucune donnée probante n’indique que l’hydrocortisone remplace la dexaméthasone avec efficacité ou innocuité dans le traitement d’une DBP évolutive ou établie. Les données à jour n’appuient pas l’administration de corticostéroïdes inhalés pour traiter la DBP.

Postnatal corticosteroids to prevent or treat bronchopulmonary dysplasia in preterm infants

Historically, postnatal corticosteroids have been used to prevent and treat bronchopulmonary dysplasia (BPD), a significant cause of morbidity and mortality in preterm infants. Administering dexamethasone to prevent BPD in the first 7 days post-birth has been associated with increasing risk for cerebral palsy, while early inhaled corticosteroids appear to be associated with an increased risk of mortality. Neither medication is presently recommended to prevent BPD. New evidence suggests that prophylactic hydrocortisone, when initiated in the first 48 hours post-birth, at a physiological dose, and in the absence of indomethacin, improves survival without BPD, with no adverse neurodevelopmental effects at 2 years. This therapy may be considered by clinicians for infants at highest risk for BPD. Routine dexamethasone therapy for all ventilator-dependent infants is not recommended, but after the first week post-birth, clinicians may consider a short course of low-dose dexamethasone (0.15 mg/kg/day to 0.2 mg/kg/day) for individual infants at high risk for, or with evolving, BPD. There is no evidence that hydrocortisone is an effective or safe alternative to dexamethasone for treating evolving or established BPD. Current evidence does not support inhaled corticosteroids for the treatment of BPD.

Survival Without Major Morbidity Among Very Low Birth Weight Infants in California

OBJECTIVES

To examine trends in survival without major morbidity and its individual components among very low birth weight infants across California and assess remaining gaps that may be opportune targets for improvement efforts.

METHODS

The study population included infants born between 2008 and 2017 with birth weights of 401 to 1500 g or a gestational age of 22 to 29 weeks. Risk-adjusted trends of survival without major morbidity and its individual components were analyzed. Survival without major morbidity was defined as the absence of death during birth hospitalization, chronic lung disease, severe peri-intraventricular hemorrhage, nosocomial infection, necrotizing enterocolitis, severe retinopathy of prematurity or related surgery, and cystic periventricular leukomalacia. Variations in adjusted rates and/or interquartile ranges were examined. To assess opportunities for additional improvement, all hospitals were reassigned to perform as if in the top quartile, and recalculation of predicted numbers were used to estimate potential benefit.

RESULTS

In this cohort of 49 333 infants across 142 hospitals, survival without major morbidity consistently increased from 62.2% to 66.9% from 2008 to 2017. Network variation decreased, with interquartile ranges decreasing from 21.1% to 19.2%. The largest improvements were seen for necrotizing enterocolitis and nosocomial infection. Bronchopulmonary dysplasia rates did not change significantly. Over the final 3 years, if all hospitals performed as well as the top quartile, an additional 621 infants per year would have survived without major morbidity, accounting for an additional 6.6% annual improvement.

CONCLUSIONS

Although trends are promising, bronchopulmonary dysplasia remains a common and persistent major morbidity, remaining a target for continued quality-improvement efforts.

Early prediction of moderate to severe bronchopulmonary dysplasia in extremely premature infants

BACKGROUND

Bronchopulmonary Dysplasia (BPD) is the commonest morbidity in extremely preterm infants (PTIs). Risk factors for BPD have been described in the era before the widespread availability of non-invasive ventilation (NIV) in the delivery room (DR). The objective of this study is to identify risk factors for Moderate/Severe BPD in an era of widespread availability of NIV in the DR.

METHODS

Detailed antenatal and postnatal data were abstracted for PTIs, 23^0/7-27^6/7 weeks GA. Multivariate logistic regression and classification and regression tree analyses (CART) identified predictors for the primary outcome of Moderate/Severe BPD.

RESULTS

Of 263 eligible infants, 59% had Moderate/Severe BPD. Moderate/Severe BPD was significantly associated with birthweight, gender, DR intubation and surfactant compared to No/Mild BPD. Of infants not intubated in the DR, 40% with No/Mild BPD and 80% with Moderate/Severe BPD received intubation by 48 hours (p < 0.05). Infants with Moderate/Severe BPD received longer duration of oxygen and mechanical (MV). On logistic regression, birthweight, gender, oxygen concentration, cumulative duration of oxygen and MV, surfactant, and blood transfusions predicted Moderate/Severe BPD. Both CART analysis and logistic regression showed duration of oxygen and MV to be the most important predictors for Moderate/Severe BPD.

CONCLUSIONS

In an era of increasing availability of NIV in the DR, lower birthweight, male gender, surfactant treatment, blood transfusions and respiratory support in the first 2-3 weeks after birth predict Moderate/Severe BPD with high sensitivity and specificity. The majority of these infants received intubation within 48 hours of birth (97%). These data suggest that early failures of NIV represent opportunities for improvement of NIV techniques and of non-invasive surfactant to avoid intubation in the first 48 hours. Furthermore, these risk factors may allow earlier identification of infants most likely to benefit from interventions to prevent or decrease severity of BPD.

Determinants of preterm infants’ deaths at the Neonatal Intensive Care Units in the Northeast Countryside in Brazil

Abstract Objectives: to assess preterm infants’ characteristics, health conditions and neonatal care effect on their death at the neonatal ICU. Methods: this was a non-concurrent cohort study, including preterm infants from three neonatal ICUs from January 1st to December 31st, 2016, followed during the neonatal period and deaths registered during the entire hospitalization. Multivariate analysis was performed using Poisson regression. Results: of the 181 preterm infants, 18.8% died during hospitalization. Associated with the outcome: a gestational age between 28 and 32 weeks (RR= 5.66; CI95%= 2.08-15.40), and less than 28 weeks (RR=9.24; CI95%=3.27-26.12), Apgar score of 5th minutes less than 7 (RR: 1.82; CI95%=1.08-3.08), use of invasive mechanical ventilation up to 3 days (RR= 4.44; CI95%= 1.66-11.87) and 4 days and more (RR=6.87; CI95%=2.58-18.27). Besides the late sepsis (RR: 3.72, CI95%=1.77-7.83), acute respiratory distress syndrome (RR=2.86, CI95%=1.49-5.46), pulmonary hemorrhage (RR=1.97; CI95%=1.40-2.77), and necrotizing enterocolitis (RR= 3.41; CI95%=1.70-6.83). Conclusions: the results suggest the importance of using strategies to improve care during childbirth, conditions for extremely premature infants, early weaning from a mechanical ventilation and prevention on nosocomial infection.

Bronchopulmonary dysplasia: A review of the pulmonary sequelae in the post-surfactant era

We describe the respiratory complications of bronchopulmonary dysplasia (BPD) in childhood and adolescence. The pathophysiology of bronchopulmonary dysplasia has evolved in the era of modern neonatal intensive care. In this review, we aim to summarise the contemporary evidence base and describe the common respiratory morbidities related to BPD including; home oxygen therapy, rehospitalisation, asthma and exercise limitation.

Effects of small for gestational age status on mortality and major morbidities in ≤750 g neonates

BACKGROUND

Controversy exists regarding the impact of small for gestational age (SGA = birth weight < 10th percentile) status on mortality and major morbidities.

AIM

To assess the effects of SGA on mortality and major morbidities in ≤750 gram (g) neonates.

STUDY DESIGN

Retrospective (01/2005-12/2017), single center study at a tertiary NICU.

SUBJECTS

SGA neonates ≤ 750 g.

OUTCOME

Effect of SGA status on mortality and major morbidities.

RESULTS

183 infants were enrolled. 103 (56.3%) were non-SGA (mean gestational age 25 + 1 weeks ± 9.9 days, mean birth weight 662.6 ± 75.2 g), and 80 (43.7%) SGA (mean gestational age 26 + 6 weeks ± 14.0 days, mean birth weight 543.9 ± 114.7 g). Mortality was 24.1% (non-SGA: 30/103 (29.1%), SGA: 14/80 (17.5%); p = 0.08). Univariable logistic regression analysis revealed a significant protective effect of SGA status on pneumothoraces (OR 0.28, 95%-CI [0.11-0.69]), IVH (≥3) (OR 0.38; 95%-CI [0.15-0.67]), and seizures (OR 0.09, 95%-CI [0.01-0.76]), but NEC (≥2a) occurred more frequently in SGA neonates (p = 0.024). Multiple logistic regression analysis found SGA status to negatively influence ROP (≥3) (OR 2.87, 95%-CI [1.14-7.23]) and need for home monitoring (OR 2.38, 95%-CI [1.05-5.41]). Other major morbidities (IVH, PVL, RDS, BPD, NEC, FIP, sepsis, hearing impairment) and mortality rates were not significantly affected, but distinct organ-specific patterns were seen.

CONCLUSION

SGA had negative effects on the rate of severe ROP and the need for home monitoring, but other major morbidities as well as mortality rates were not significantly affected. In the future, it will be important to delineate underlying pathophysiological mechanisms that contribute to this pattern.

Do transport factors increase the risk of severe brain injury in outborn infants <33 weeks gestational age?

OBJECTIVE

We evaluated transport factors and postnatal practices to identify modifiable risk factors for SBI.

STUDY DESIGN

Retrospective review of Canadian Neonatal Transport Network data linked to Canadian Neonatal Network data for outborns <33 weeks gestational age (GA), during January 2014 to December 2015. SBI was defined as grade 3 or 4 intraventricular hemorrhage or parenchymal echogenicity, including hemorrhagic and/or ischemic lesions.

RESULT

Among 781 infants, 115 (14.7%) had SBI with range 5.6-40% among transport teams. In multivariable analysis, SBI was associated with GA [0.77 (0.71, 0.85)] per week, receipt of chest compressions and/or epinephrine at delivery [1.81 (1.08, 3.05)] and receipt of fluid boluses [1.61 (1.00, 2.58)].

CONCLUSIONS

Risk factors for SBI were related to the condition at birth and immediate postnatal management and not related to transport factors. These results highlight the importance of maternal transfer to perinatal centers to allow optimization of perinatal management.

Early preterm infants with abnormal psychomotor neurodevelopmental outcome at age two show alterations in amplitude-integrated electroencephalography signals

INTRODUCTION

Recent studies showed that neurodevelopment in preterm infants can be predicted by using amplitude-integrated electroencephalography (aEEG)-derived parameters. In our previous study we demonstrated that aEEG could be useful in predicting neurodevelopmental outcome in very preterm infants at the corrected age of 2 years.

AIM

The aim of this study was to further evaluate aEEG for predicting neurodevelopmental outcome at the at the corrected age of 2 years in preterm infants.

METHODS

Between July 2010 and June 2016 440 very preterm infants were eligible for the study at Innsbruck Medical University Hospital. The aEEG was evaluated for the Burdjalov score in 306 preterm infants (mean gestational age 29.5 weeks; range: 24.1-31.9 weeks). At the corrected age of 2 years outcome was assessed by the Bayley Scales of Infant and Toddler Development.

RESULTS

The cohort was divided into three subgroups: 248 infants with normal outcome, 40 infants with delayed outcome and 18 infants with abnormal outcome. Burdjalov scores were lower in infants with delayed outcome than in infants with normal outcome and even lower in infants with abnormal outcome. Post-hoc analysis showed significant differences between normal and delayed psychomotor outcome at 18-24 h (5 (3;6) versus 3 (3;5), p = .024), 30-36 h (6 (4;8) versus 4 (4;6), p = .033), 42-48 h (7 (5;8.5) versus 4 (4;7), p = .003), 54-60 h (7 (6;9) versus 5 (4;7), p = .003), 66-72 h (8 (6;9) versus 6.5 (4.25;7.75), p = .027) and week one (8 (7;10) versus 6.5 (5;8), p = .021). Additionally, when comparing normal to abnormal outcome, a significant difference was found at week four (12 (9;12) versus 8 (7;10), p = .024). The Burdjalov score was only predictive for a delayed psychomotor outcome, presenting the highest area under the curve (0.690) at week two of life.

CONCLUSION

We observed differences in aEEG signals and neurodevelopmental outcome at the corrected age of 2 years, especially for psychomotor outcome. The predictive value of the Burdjalov score regarding neurodevelopmental outcome at the corrected age of 2 years in preterm infants was low.

Outcomes and care practices for preterm infants born at less than 33 weeks' gestation: a quality-improvement study

BACKGROUND

Preterm birth is the leading cause of morbidity and mortality in children younger than 5 years. We report the changes in neonatal outcomes and care practices among very preterm infants in Canada over 14 years within a national, collaborative, continuous quality-improvement program.

METHODS

We retrospectively studied infants born at 23-32 weeks' gestation who were admitted to tertiary neonatal intensive care units that participated in the Evidence-based Practice for Improving Quality program in the Canadian Neonatal Network from 2004 to 2017. The primary outcome was survival without major morbidity during the initial hospital admission. We quantified changes using process-control charts in 6-month intervals to identify special-cause variations, adjusted regression models for yearly changes, and interrupted time series analyses.

RESULTS

The final study population included 50 831 infants. As a result of practice changes, survival without major morbidity increased significantly (56.6% [669/1183] to 70.9% [1424/2009]; adjusted odds ratio [OR] 1.08, 95% confidence interval [CI] 1.06-1.10, per year) across all gestational ages. Survival of infants born at 23-25 weeks' gestation increased (70.8% [97/137] to 74.5% [219/294]; adjusted OR 1.03, 95% CI 1.02-1.05, per year). Changes in care practices included increased use of antenatal steroids (83.6% [904/1081] to 88.1% [1747/1983]), increased rates of normothermia at admission (44.8% [520/1160] to 67.5% [1316/1951]) and reduced use of pulmonary surfactant (52.8% [625/1183] to 42.7% [857/2009]).

INTERPRETATION

Network-wide quality-improvement activities that include better implementation of optimal care practices can yield sustained improvement in survival without morbidity in very preterm infants.

Very preterm infant outcomes according to timing of birth

INTRODUCTION

Extremely preterm infants are a population of high risk for morbidity and mortality. NICU's staffing is often lower during nights, weekends and holidays than weekdays, and this fact may contribute to higher morbidities and mortality. Our aim was to analyze the neonatal morbidity and mortality of very preterm infants delivered at our center and admitted to the NICU during the night period, weekends and holidays compared to that registered on weekday admissions.

METHODS

A retrospective study was conducted at our level III NICU, including data on mother, pregnancy, delivery, and neonatal outcomes of preterm infants with a gestational age below 30 weeks, admitted between January 1st 2005 and December 31st 2017. Statistical analysis was performed using IBM SPSS® Statistics 23.

RESULTS

220 infants were included in the study; median gestational age 27 weeks (min = 23; max = 29); median birth weight of 922 g (min = 360; max1555); 95 (43.2%) infants were delivered during weekdays and 125 (56.8%) were delivered during weeknights, weekends and holidays. There were no differences on mother's age, pregnancy complications, Apgar scores, birth weights, gestational ages and gender between the two groups. C-sections (p = 0.006), and small for gestational age infants (p = 0.010) were more prevalent in week day births. Chorioamnionitis with chorionic vasculitis (p = 0.028) and cystic periventricular leukomalacia (p = 0.032) were more prevalent in those delivered during the night period, weekends and holidays. In the multivariate analysis, cystic periventricular leukomalacia was not associated to a deliver during weeknights, weekends and holidays (OR = 0.580; 95% CI: 0.19-1.71, p = 0.324).

CONCLUSION

We did not find any increased morbidity and mortality associated with a birth during nights, weekends and holidays compared to that registered on weekday admissions.

Inhaled nitric oxide as an adjunct to neonatal resuscitation in premature infants: a pilot, double blind, randomized controlled trial

BACKGROUND

Nitric oxide (NO) plays an important role in normal postnatal transition. Our aims were to determine whether adding inhaled NO (iNO) decreases supplemental oxygen exposure in preterm infants requiring positive pressure ventilation (PPV) during resuscitation and to study iNO effects on heart rate (HR), oxygen saturation (SpO₂), and need for intubation during the first 20 min of life.

METHODS

This was a pilot, double-blind, randomized, placebo-controlled trial. Infants 25 0/7-31 6/7 weeks' gestational age requiring PPV with supplemental oxygen during resuscitation were enrolled. PPV was initiated with either oxygen (FiO₂-0.30) + iNO at 20 ppm (iNO group) or oxygen (FiO₂-0.30) + nitrogen (placebo group). Oxygen was titrated targeting defined SpO₂ per current guidelines. After 10 min, iNO/nitrogen was weaned stepwise per protocol and terminated at 17 min.

RESULTS

Twenty-eight infants were studied (14 per group). The mean gestational age in both groups was similar. Cumulative FiO₂ and rate of exposure to high FiO₂ (>0.60) were significantly lower in the iNO group. There were no differences in HR, SpO₂, and need for intubation.

CONCLUSIONS

Administration of iNO as an adjunct during neonatal resuscitation is feasible without side effects. It diminishes exposure to high levels of supplemental oxygen.

Short-term outcomes of extremely preterm infants at discharge: a multicenter study from Guangdong province during 2008-2017

BACKGROUND

An increasing number of extremely preterm (EP) infants have survived worldwide. However, few data have been reported from China. This study was designed to investigate the short-term outcomes of EP infants at discharge in Guangdong province.

METHODS

A total of 2051 EP infants discharged from 26 neonatal intensive care units during 2008-2017 were enrolled. The data from 2008 to 2012 were collected retrospectively, and from 2013 to 2017 were collected prospectively. Their hospitalization records were reviewed.

RESULTS

During 2008-2017, the mean gestational age (GA) was 26.68 ± 1.00 weeks and the mean birth weight (BW) was 935 ± 179 g. The overall survival rate at discharge was 52.5%. There were 321 infants (15.7%) died despite active treatment, and 654 infants (31.9%) died after medical care withdrawal. The survival rates increased with advancing GA and BW (p < 0.001). The annual survival rate improved from 36.2% in 2008 to 59.3% in 2017 (p < 0.001). EP infants discharged from hospitals in Guangzhou and Shenzhen cities had a higher survival rate than in others (p < 0.001). The survival rate of EP infants discharged from general hospitals was lower than in specialist hospitals (p < 0.001). The major complications were neonatal respiratory distress syndrome, 88.0% (1804 of 2051), bronchopulmonary dysplasia, 32.3% (374 of 1158), retinopathy of prematurity (any grade), 45.1% (504 of 1117), necrotizing enterocolitis (any stage), 10.1% (160 of 1588), intraventricular hemorrhages (any grade), 37.4% (535 of 1431), and blood culture-positive nosocomial sepsis, 15.7% (250 of 1588). The multivariate logistic regression analysis indicated that improved survival of EP infants was associated with discharged from specialist hospitals, hospitals located in high-level economic development region, increasing gestational age, increasing birth weight, antenatal steroids use and a history of premature rupture of membranes. However, twins or multiple births, Apgar ≤7 at 5 min, cervical incompetence, and decision to withdraw care were associated with decreased survival.

CONCLUSIONS

Our study revealed the short-term outcomes of EP infants at discharge in China. The overall survival rate was lower than the developed countries, and medical care withdrawal was a serious problem. Nonetheless, improvements in care and outcomes have been made annually.

Mortality Rate-Dependent Variations in the Timing and Causes of Death in Extremely Preterm Infants Born at 23-24 Weeks' Gestation

OBJECTIVES

To determine mortality rate-dependent variations in the timing and causes of death, and to subsequently identify the clinical factors associated with decreased mortality in extremely preterm infants born at 23-24 weeks' gestation.

DESIGN

A retrospective cohort study.

SETTING

Korean Neonatal Network registry that includes all level greater than or equal to 3 neonatal ICUs in Korea.

PATIENTS

Eligible, actively treated infants born at 23-24 weeks' gestation (n = 574) from January 2014 to December 2016 were arbitrarily categorized based on institutional mortality rates of less than or equal to 50% (group I, n = 381) and greater than 50% (group II, n = 193). The primary outcome was mortality before discharge and the timing and causes of death according to the mortality rate.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The overall mortality rate was significantly lower in group I (40.7%) than in group II (79.3%). Regarding causes of death, mortalities due to cardiorespiratory, infectious, and gastrointestinal causes were significantly lower in group I than in group II. Mortality rates were significantly lower in group I, including all the subgroups that were categorized according to the timing of death, than in group II. The multivariate analyses showed that antenatal corticosteroid use, absence of oligohydramnios, birth weight, and body temperature at admission to the neonatal ICU were significantly associated with reduced mortality.

CONCLUSIONS

The reduced mortality rate among the infants born at 23-24 weeks' gestation was attributable to decreased mortality ascribed to cardiorespiratory, infectious, and gastrointestinal causes, and it was associated with antenatal steroid use and body temperature at admission to the neonatal ICU.

Neonatal transport metrics and quality improvement in a regional transport service

Sick neonates in non-tertiary centers rely on the expert skills of neonatal transport teams (NTTs) and efficient systems to provide safe and timely transport to tertiary centers. Quality metrics to measure and compare performance among transport teams are essential to ensure delivery of high-quality care and efficient use of limited and costly resources. We review the most relevant quality metrics available in neonatal transport and key issues to consider during their utilization. The use of quality metrics for quality improvement is described through the experience of a neonatal transport program based at a quaternary children's hospital in Canada.

The International Network for Evaluating Outcomes (iNeo) of neonates: evolution, progress and opportunities

Neonates born very preterm (before 32 weeks' gestational age), are a significant public health concern because of their high-risk of mortality and life-long disability. In addition, caring for very preterm neonates can be expensive, both during their initial hospitalization and their long-term cost of permanent impairments. To address these issues, national and regional neonatal networks around the world collect and analyse data from their constituents to identify trends in outcomes, and conduct benchmarking, audit and research. Improving neonatal outcomes and reducing health care costs is a global problem that can be addressed using collaborative approaches to assess practice variation between countries, conduct research and implement evidence-based practices. The International Network for Evaluating Outcomes (iNeo) of neonates was established in 2013 with the goal of improving outcomes for very preterm neonates through international collaboration and comparisons. To date, 10 national or regional population-based neonatal networks/datasets participate in iNeo collaboration. The initiative now includes data on >200,000 very preterm neonates and has conducted important epidemiological studies evaluating outcomes, variations and trends. The collaboration has also surveyed >320 neonatal units worldwide to learn about variations in practices, healthcare service delivery, and physical, environmental and manpower related factors and support services for parents. The iNeo collaboration serves as a strong international platform for Neonatal-Perinatal health services research that facilitates international data sharing, capacity building, and global efforts to improve very preterm neonate care.

How do neonatal units within the Australian and New Zealand Neonatal Network manage ex-preterm infants with severe chronic lung disease still requiring major respiratory support at term?

AIM

The aim was to survey the Australian and New Zealand Neonatal Network (ANZNN) member units regarding current services and management guidelines for the ex-premature infant with severe chronic lung disease (CLD) still requiring significant respiratory support at term.

METHODS

A 16-question survey was sent to clinical directors of all Level 3 units in Australia and New Zealand via the network. Reminder emails were sent, as required, to prompt a satisfactory response rate.

RESULTS

Survey responses were received from 26 of the 29 (90%) ANZNN Level 3 units. At 37 weeks' corrected gestation, over 90% of the units provide ongoing respiratory support in the neonatal intensive care unit (NICU). However, by 50 weeks, ongoing care is provided in several settings, including NICU, high dependency unit (HDU)/paediatric intensive care unit or respiratory wards. The majority (76%) of units arrange transfer on an ad hoc basis, but six units (24%) have set criteria for transfer based on gestation, workload and respiratory requirement. Three units declared a maximum age in NICU (44, 46 or 48 weeks). A variety of approaches were used to identify infants who were likely to require transfer, and 78% of units had a staff member assigned to assist transition. Three units stated that they had a home ventilation programme suitable for these infants. No unit supplied a guideline on tracheostomy or specific respiratory management post-term.

CONCLUSION

Despite a significant number of babies requiring ongoing support for severe CLD, the location of the service appears very variable, and there is a lack of specific written guidelines.

Association of Socioeconomic Status and Brain Injury With Neurodevelopmental Outcomes of Very Preterm Children

IMPORTANCE

Studies of socioeconomic status and neurodevelopmental outcome in very preterm neonates have not sensitively accounted for brain injury.

OBJECTIVE

To determine the association of brain injury and maternal education with motor and cognitive outcomes at age 4.5 years in very preterm neonates.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study of preterm neonates (24-32 weeks' gestation) recruited August 16, 2006, to September 9, 2013, at British Columbia Women's Hospital in Vancouver, Canada. Analysis of 4.5-year outcome was performed in 2018.

MAIN OUTCOMES AND MEASURES

At age 4.5 years, full-scale IQ assessed using the Wechsler Primary and Preschool Scale of Intelligence, Fourth Edition, and motor outcome by the percentile score on the Movement Assessment Battery for Children, Second Edition.

RESULTS

Of 226 survivors, neurodevelopmental outcome was assessed in 170 (80 [47.1%] female). Based on the best model to assess full-scale IQ accounting for gestational age, standardized β coefficients demonstrated the effect size of maternal education (standardized β = 0.21) was similar to that of white matter injury volume (standardized β = 0.23) and intraventricular hemorrhage (standardized β = 0.23). The observed and predicted cognitive scores in preterm children born to mothers with postgraduate education did not differ in those with and without brain injury. The best-performing model to assess for motor outcome accounting for gestational age included being small for gestational age, severe intraventricular hemorrhage, white matter injury volume, and chronic lung disease.

CONCLUSIONS AND RELEVANCE

At preschool age, cognitive outcome was comparably associated with maternal education and neonatal brain injury. The association of brain injury with poorer cognition was attenuated in children born to mothers of higher education level, suggesting opportunities to promote optimal outcomes.

Respiratory Medications in Infants <29 Weeks during the First Year Postdischarge: The Prematurity and Respiratory Outcomes Program (PROP) Consortium

OBJECTIVE

To determine patterns of respiratory medications used in neonatal intensive care unit graduates.

STUDY DESIGN

The Prematurity Respiratory Outcomes Program enrolled 835 babies <29 weeks of gestation in the first week. Of 751 survivors, 738 (98%) completed at least 1, and 85% completed all 4, postdischarge medication usage in-person/telephone parental questionnaires requested at 3, 6, 9, and 12 months of corrected age. Respiratory drug usage over the first year of life after in neonatal intensive care unit discharge was analyzed.

RESULTS

During any given quarter, 66%-75% of the babies received no respiratory medication and 45% of the infants received no respiratory drug over the first year. The most common postdischarge medication was the inhaled bronchodilator albuterol; its use increased significantly from 13% to 31%. Diuretic usage decreased significantly from 11% to 2% over the first year. Systemic steroids (prednisone, most commonly) were used in approximately 5% of subjects in any one quarter. Inhaled steroids significantly increased over the first year from 9% to 14% at 12 months. Drug exposure changed significantly based on gestational age with 72% of babies born at 23-24 weeks receiving at least 1 respiratory medication but only 40% of babies born at 28 weeks. Overall, at some time in the first year, 55% of infants received at least 1 drug including an inhaled bronchodilator (45%), an inhaled steroid (22%), a systemic steroid (15%), or diuretic (12%).

CONCLUSION

Many babies born at <29 weeks have no respiratory medication exposure postdischarge during the first year of life. Inhaled medications, including bronchodilators and steroids, increase over the first year.