Neurodevelopmental outcome of bronchopulmonary dysplasia

Neurodevelopmental Outcomes of Preterm Infants Born <29 Weeks with Bronchopulmonary Dysplasia-Associated Pulmonary Hypertension: A Multicenter Study

OBJECTIVE

 This study aimed to determine neurodevelopmental outcomes of preterm infants born at <29 weeks' gestational age (GA) with bronchopulmonary dysplasia and pulmonary hypertension (BPD-PH) at 18 to 24 months' corrected age (CA).

STUDY DESIGN

 In this retrospective cohort study, preterm infants born at <29 weeks' GA between January 2016 and December 2019, admitted to level 3 neonatal intensive care units, who developed BPD and were evaluated at 18 to 24 months' CA in the neonatal follow-up clinics were included. We compared demographic characteristics and neurodevelopmental outcomes between the two groups: Group I: BPD with PH and Group II: BPD with no PH, using univariate and multivariate regression models. The primary outcome was a composite of death or neurodevelopmental impairment (NDI). NDI was defined as any Bayley-III score < 85 on one or more of the cognitive, motor, or language composite scores.

RESULTS

 Of 366 eligible infants, 116 (Group I [BPD-PH] =7, Group II [BPD with no PH] = 109) were lost to follow-up. Of the remaining 250 infants, 51 in Group I and 199 in Group II were followed at 18 to 24 months' CA. Group I and Group II had median (interquartile range [IQR]) birthweights of 705 (325) and 815 g (317; p = 0.003) and median GAs (IQR) were 25 (2) and 26 weeks (2; p = 0.015) respectively. Infants in the BPD-PH group (Group I) were more likely to have mortality or NDI (adjusted odds ratio: 3.82; bootstrap 95% confidence interval; 1.44-40.87).

CONCLUSION

 BPD-PH in infants born at <29 weeks' GA is associated with increased odds of the composite outcome of death or NDI at 18 to 24 months' CA.

KEY POINTS

· Long-term neurodevelopmental follow-up of preterm infants born <29 weeks' GA.. · Association of neurodevelopmental outcomes with BPD-associated PH.. · Need for longitudinal follow-up of children with BPD-associated PH..

Delineating morbidity patterns in preterm infants at near-term age using a data-driven approach

BACKGROUND

Long-term survival after premature birth is significantly determined by development of morbidities, primarily affecting the cardio-respiratory or central nervous system. Existing studies are limited to pairwise morbidity associations, thereby lacking a holistic understanding of morbidity co-occurrence and respective risk profiles.

METHODS

Our study, for the first time, aimed at delineating and characterizing morbidity profiles at near-term age and investigated the most prevalent morbidities in preterm infants: bronchopulmonary dysplasia (BPD), pulmonary hypertension (PH), mild cardiac defects, perinatal brain pathology and retinopathy of prematurity (ROP). For analysis, we employed two independent, prospective cohorts, comprising a total of 530 very preterm infants: AIRR ("Attention to Infants at Respiratory Risks") and NEuroSIS ("Neonatal European Study of Inhaled Steroids"). Using a data-driven strategy, we successfully characterized morbidity profiles of preterm infants in a stepwise approach and (1) quantified pairwise morbidity correlations, (2) assessed the discriminatory power of BPD (complemented by imaging-based structural and functional lung phenotyping) in relation to these morbidities, (3) investigated collective co-occurrence patterns, and (4) identified infant subgroups who share similar morbidity profiles using machine learning techniques.

RESULTS

First, we showed that, in line with pathophysiologic understanding, BPD and ROP have the highest pairwise correlation, followed by BPD and PH as well as BPD and mild cardiac defects. Second, we revealed that BPD exhibits only limited capacity in discriminating morbidity occurrence, despite its prevalence and clinical indication as a driver of comorbidities. Further, we demonstrated that structural and functional lung phenotyping did not exhibit higher association with morbidity severity than BPD. Lastly, we identified patient clusters that share similar morbidity patterns using machine learning in AIRR (n=6 clusters) and NEuroSIS (n=8 clusters).

CONCLUSIONS

By capturing correlations as well as more complex morbidity relations, we provided a comprehensive characterization of morbidity profiles at discharge, linked to shared disease pathophysiology. Future studies could benefit from identifying risk profiles to thereby develop personalized monitoring strategies.

TRIAL REGISTRATION

AIRR: DRKS.de, DRKS00004600, 28/01/2013. NEuroSIS: ClinicalTrials.gov, NCT01035190, 18/12/2009.

GSDMD gene knockout alleviates hyperoxia-induced hippocampal brain injury in neonatal mice

BACKGROUND

Neonatal hyperoxia exposure is associated with brain injury and poor neurodevelopment outcomes in preterm infants. Our previous studies in neonatal rodent models have shown that hyperoxia stimulates the brain's inflammasome pathway, leading to the activation of gasdermin D (GSDMD), a key executor of pyroptotic inflammatory cell death. Moreover, we found pharmacological inhibition of caspase-1, which blocks GSDMD activation, attenuates hyperoxia-induced brain injury in neonatal mice. We hypothesized that GSDMD plays a pathogenic role in hyperoxia-induced neonatal brain injury and that GSDMD gene knockout (KO) will alleviate hyperoxia-induced brain injury.

METHODS

Newborn GSDMD knockout mice and their wildtype (WT) littermates were randomized within 24 h after birth to be exposed to room air or hyperoxia (85% O2) from postnatal days 1 to 14. Hippocampal brain inflammatory injury was assessed in brain sections by immunohistology for allograft inflammatory factor 1 (AIF1) and CD68, markers of microglial activation. Cell proliferation was evaluated by Ki-67 staining, and cell death was determined by TUNEL assay. RNA sequencing of the hippocampus was performed to identify the transcriptional effects of hyperoxia and GSDMD-KO, and qRT-PCR was performed to confirm some of the significantly regulated genes.

RESULTS

Hyperoxia-exposed WT mice had increased microglia consistent with activation, which was associated with decreased cell proliferation and increased cell death in the hippocampal area. Conversely, hyperoxia-exposed GSDMD-KO mice exhibited considerable resistance to hyperoxia as O2 exposure did not increase AIF1 + , CD68 + , or TUNEL + cell numbers or decrease cell proliferation. Hyperoxia exposure differentially regulated 258 genes in WT and only 16 in GSDMD-KO mice compared to room air-exposed WT and GSDMD-KO, respectively. Gene set enrichment analysis showed that in the WT brain, hyperoxia differentially regulated genes associated with neuronal and vascular development and differentiation, axonogenesis, glial cell differentiation, hypoxia-induced factor 1 pathway, and neuronal growth factor pathways. These changes were prevented by GSDMD-KO.

CONCLUSIONS

GSDMD-KO alleviates hyperoxia-induced inflammatory injury, cell survival and death, and alterations of transcriptional gene expression of pathways involved in neuronal growth, development, and differentiation in the hippocampus of neonatal mice. This suggests that GSDMD plays a pathogenic role in preterm brain injury, and targeting GSDMD may be beneficial in preventing and treating brain injury and poor neurodevelopmental outcomes in preterm infants.

Systemic corticosteroids for the prevention of bronchopulmonary dysplasia, a network meta-analysis

BACKGROUND

Despite considerable improvement in outcomes for preterm infants, rates of bronchopulmonary dysplasia (BPD) remain high, affecting an estimated 33% of very low birthweight infants, with corresponding long-term respiratory and neurosensory issues. Systemic corticosteroids can address the inflammation underlying BPD, but the optimal regimen for prevention of this disease, balancing of the benefits with the potentially meaningful risks of systemic corticosteroids, continues to be a medical quandary. Numerous studies have shown that systemic corticosteroids, particularly dexamethasone and hydrocortisone, effectively treat or prevent BPD. However, concerning short and long-term side effects have been reported and the optimal approach to corticosteroid treatment remains unclear.

OBJECTIVES

To determine whether differences in efficacy and safety exist between high-dose dexamethasone, moderate-dose dexamethasone, low-dose dexamethasone, hydrocortisone, and placebo in the prevention of BPD, death, the composite outcome of death or BPD, and other relevant morbidities, in preterm infants through a network meta-analysis, generating both pairwise comparisons between all treatments and rankings of the treatments.

SEARCH METHODS

We searched the Cochrane Library for all systematic reviews of systemic corticosteroids for the prevention of BPD and searched for completed and ongoing studies in the following databases in January 2023: Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and clinical trial databases.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in preterm infants (< 37 weeks' gestation) at risk for BPD that evaluated systemic corticosteroids (high-dose [≥ 4 mg/kg cumulative dose] dexamethasone, moderate-dose [≥ 2 to < 4 mg/kg] dexamethasone, low-dose [< 2 mg/kg] dexamethasone, or hydrocortisone) versus control or another systemic corticosteroid.

DATA COLLECTION AND ANALYSIS

Our main information sources were the systematic reviews, with reference to the original manuscript only for data not included in these reviews. Teams of two paired review authors independently performed data extraction, with disagreements resolved by discussion. Data were entered into Review Manager 5 and exported to R software for network meta-analysis (NMA). NMA was performed using a frequentist model with random-effects. Two separate networks were constructed, one for early (< seven days) initiation of treatment and one for late (≥ seven days) treatment initiation, to reflect the different patient populations evaluated. We assessed the certainty of evidence derived from the NMA for our primary outcomes using principles of the GRADE framework modified for application to NMA.

MAIN RESULTS

We included 59 studies, involving 6441 infants, in our analyses. Only six of the included studies provided direct comparisons between any of the treatment (dexamethasone or hydrocortisone) groups, forcing network comparisons between treatments to rely heavily on indirect evidence through comparisons with placebo/no treatment groups. Thirty-one studies evaluated early corticosteroid treatment, 27 evaluated late corticosteroid treatment, and one study evaluated both early and late corticosteroid treatments. Early treatment (prior to seven days after birth): Benefits:NMA for early treatment showed only moderate-dose dexamethasone to decrease the risk of BPD at 36 weeks' postmenstrual age (PMA) compared with control (RR 0.56, 95% CI 0.39 to 0.80; moderate-certainty evidence), although the other dexamethasone dosing regimens may have similar effects compared with control (high-dose dexamethasone, RR 0.71, 95% CI 0.50 to 1.01; low-certainty evidence; low-dose dexamethasone, RR 0.83, 95% CI 0.67 to 1.03; low-certainty evidence). Other early treatment regimens may have little or no effect on the risk of death at 36 weeks' PMA. Only moderate-dose dexamethasone decreased the composite outcome of death or BPD at 36 weeks' PMA compared with control (RR 0.77, 95% CI 0.60 to 0.98; moderate-certainty evidence).

HARMS

Low-dose dexamethasone increased the risk for cerebral palsy (RR 1.92, 95% CI 1.12 to 3.28; moderate-certainty evidence) compared with control. Hydrocortisone may decrease the risk of major neurosensory disability versus low-dose dexamethasone (RR 0.65, 95% CI 0.41 to 1.01; low-certainty evidence). Late treatment (at seven days or later after birth): Benefits: NMA for late treatment showed high-dose dexamethasone to decrease the risk of BPD both versus hydrocortisone (RR 0.66, 95% CI 0.51 to 0.85; low-certainty evidence) and versus control (RR 0.72, CI 0.59 to 0.87; moderate-certainty evidence). The late treatment regimens evaluated may have little or no effect on the risk of death at 36 weeks' PMA. High-dose dexamethasone decreased risk for the composite outcome of death or BPD compared with all other treatments (control, RR 0.69, 95% CI 0.59 to 0.80, high-certainty evidence; hydrocortisone, RR 0.69, 95% CI 0.58 to 0.84, low-certainty evidence; low-dose dexamethasone, RR 0.73, 95% CI 0.60 to 0.88, low-certainty evidence; moderate-dose dexamethasone, RR 0.76, 95% CI 0.62 to 0.93, low-certainty evidence).

HARMS

No effect was observed for the outcomes of major neurosensory disability or cerebral palsy. The evidence for the primary outcomes was of overall low certainty, with notable deductions for imprecision and heterogeneity across the networks.

AUTHORS' CONCLUSIONS

While early treatment with moderate-dose dexamethasone or late treatment with high-dose dexamethasone may lead to the best effects for survival without BPD, the certainty of the evidence is low. There is insufficient evidence to guide this therapy with regard to plausible adverse long-term outcomes. Further RCTs with direct comparisons between systemic corticosteroid treatments are needed to determine the optimal treatment approach, and these studies should be adequately powered to evaluate survival without major neurosensory disability.

Effect of biomedical complications on very and extremely preterm children's language

Introduction

Very and extremely preterm children have been found to show delays in the development of language in early years. In some investigations, however, a rigorous control of biomedical complications, such as Periventricular Leukomalacia (PVL), Intraventricular Hemorrhage (IVH) or Bronchopulmonary Dysplasia (BPD), does not always exist. For that reason, a confounding effect of low gestational age and biomedical complications may lead to erroneous conclusions about the effect of gestational age.

Methods

In this investigation we compare language development [use of words, sentence complexity and mean length of the three longest utterances (MLU3)] of three groups of Chilean children at 24 months of age (corrected age for preterm children). The first group was composed of 42 healthy full-term children (Full term group: FT), the second group of 60 preterm children born below 32 gestational weeks without medical complications (low risk preterm group: LRPT), and the third group was composed of 64 children below 32 gestational weeks who had medical complications (High risk preterm group: HRPT). The three groups were similar in terms of gender distribution, maternal education, and socio-economic environment. The instrument used to assess language was the Communicative Development Inventories (CDI). In addition, the Ages and Stages Questionnaire-3 (ASQ-3) was also used to assess other developmental dimensions.

Results

The results indicate that HRPT and LRPT children obtained significantly lower results than the FT group in the three language measures obtained through the CDI. No significant differences were observed between the HRPT and the LRPT groups, although the HRPT obtained the lowest results in the three CDI measures. The results obtained through the administration of the ASQ-3 confirm the delay of both preterm groups in communicative development when compared to the FT group. No significant differences between the FT and the PT groups were observed in gross motor, fine motor and problem solving dimensions of the ASQ-3. The LRPT group obtained results that were significantly higher than those of the FT group and the HRPT group in gross motor development.

Discussion

These results seem to indicate that the area of language development is particularly influenced by very or extremely low gestational age.

Development of cortical folds in the human brain: An attempt to review biological hypotheses, early neuroimaging investigations and functional correlates

The folding of the human brain mostly takes place in utero, making it challenging to study. After a few pioneer studies looking into it in post-mortem foetal specimen, modern approaches based on neuroimaging have allowed the community to investigate the folding process in vivo, its normal progression, its early disturbances, and its relationship to later functional outcomes. In this review article, we aimed to first give an overview of the current hypotheses on the mechanisms governing cortical folding. After describing the methodological difficulties raised by its study in fetuses, neonates and infants with magnetic resonance imaging (MRI), we reported our current understanding of sulcal pattern emergence in the developing brain. We then highlighted the functional relevance of early sulcal development, through recent insights about hemispheric asymmetries and early factors influencing this dynamic such as prematurity. Finally, we outlined how longitudinal studies have started to relate early folding markers and the child's sensorimotor and cognitive outcome. Through this review, we hope to raise awareness on the potential of studying early sulcal patterns both from a fundamental and clinical perspective, as a window into early neurodevelopment and plasticity in relation to growth in utero and postnatal environment of the child.

Inhibition of hippocampal cyclin-dependent kinase 5 activity ameliorates learning and memory dysfunction in a mouse model of bronchopulmonary dysplasia

AIMS

Oxygen therapy plays a vital role in the development of bronchopulmonary dysplasia (BPD), which is the independent risk factor for neurodevelopment deficits in premature infants. However, the effect of hippocampal cyclin-dependent kinase 5 (CDK5) on BPD-associated neurodevelopment deficits is not fully understood.

METHODS

Mice were placed in a hyperoxia chamber from postnatal Day 1 to Day 7. Hematoxylin and eosin staining was used to evaluate the lung histomorphological characteristics. Learning and memory functions of mice were detected by Morris water maze. TUNEL staining was applied to measure the number of apoptotic cells. The expression of CDK5, apoptosis-related protein, and neuroplasticity-related proteins were analyzed by Western blot. Golgi staining was used to assess the structure of dendritic spines.

RESULTS

Hyperoxia-induced BPD mice showed a long-term learning and memory dysfunction, more severe neuronal apoptosis, and a decline of synaptic plasticity. Inhibition of CDK5 overactivation ameliorated cognitive deficits, neuronal apoptosis, and synaptic plasticity disorders in BPD mice.

CONCLUSIONS

This study first found a vital role of CDK5 in BPD-associated neurodevelopmental disorders. Inhibition of CDK5 overexpression could effectively improve cognitive dysfunctions in BPD mice, which indicated that hippocampal CDK5 may be a new target for prevention and treatment in learning and memory dysfunction of BPD.

Association Between Enteral Supplementation With High-Dose Docosahexaenoic Acid and Risk of Bronchopulmonary Dysplasia in Preterm Infants: A Systematic Review and Meta-analysis

IMPORTANCE

High-dose docosahexaenoic acid (DHA), a long-chain polyunsaturated fatty acid, may affect the risk of bronchopulmonary dysplasia (BPD). However, high-level summative evidence supporting such clinical association in very preterm infants is lacking.

OBJECTIVE

To examine the association between enteral supplementation with high-dose DHA during the neonatal period and the risk of BPD in preterm infants born at less than 29 weeks' gestation.

DATA SOURCES

PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, medRxiv, and ClinicalTrials.gov were searched from inception to August 1, 2022, for eligible articles with no language restrictions.

STUDY SELECTION

Randomized clinical trials (RCTs) were eligible for inclusion (1) if their interventions involved direct administration of a minimum DHA supplementation of 40 mg/kg/d or breast milk or formula feeding of at least 0.4% of total fatty acids, and (2) if they reported data on either BPD, death, BPD severity, or a combined outcome of BPD and death.

DATA EXTRACTION AND SYNTHESIS

Two investigators completed independent review of titles and abstracts, full text screening, data extraction, and quality assessment using the Cochrane Risk of Bias 2.0. Risk ratios (RRs) with 95% CIs were pooled using random-effect meta-analyses.

MAIN OUTCOMES AND MEASURES

Primary outcome was BPD using trial-specific definitions, which was further stratified for RCTs that used a more stringent BPD definition based on systematic pulse oximetry assessment at 36 weeks' postmenstrual age. Other outcomes were BPD, death, BPD severity, or combined BPD and death.

RESULTS

Among the 2760 studies screened, 4 RCTs were included, which involved 2304 infants (1223 boys [53.1%]; mean [SD] gestational age, 26.5 [1.6] weeks). Enteral supplementation with high-dose DHA was associated with neither BPD (4 studies [n = 2186 infants]; RR, 1.07 [95% CI, 0.86-1.34]; P = .53; I2 = 72%) nor BPD or death (4 studies [n = 2299 infants]; RR, 1.04 [95% CI, 0.91-1.18]; P = .59; I2 = 61%). However, an inverse association with BPD was found in RCTs that used a more stringent BPD definition (2 studies [n = 1686 infants]; RR, 1.20 [95% CI, 1.01-1.42]; P = .04; I2 = 48%). Additionally, DHA was inversely associated with moderate-to-severe BPD (3 studies [n = 1892 infants]; RR, 1.16 [95% CI, 1.04-1.29]; P = .008; I2 = 0%).

CONCLUSIONS AND RELEVANCE

Results of this study showed that enteral supplementation with high-dose DHA in the neonatal period was not associated overall with BPD, but an inverse association was found in the included RCTs that used a more stringent BPD definition. These findings suggest that high-dose DHA supplementation should not be recommended to prevent BPD in very preterm infants.

Survival and Neurodevelopmental Outcome of Extremely-Low-Birth-Weight Infants at One Year of Age-A Prospective, Descriptive Study

OBJECTIVES

To study the survival rates at discharge and neurodevelopmental outcome at 1 y of corrected age (CA) of extremely-low-birth-weight ELBW neonates.

METHODS

This prospective, descriptive study was conducted in a tertiary care level III extramural NICU of a teaching hospital. Forty-nine extremely-low-birth-weight (ELBW) neonates were enrolled in the study from July 2017 to June 2018. Baseline demographic data, morbidities during NICU stay, and survival at discharge for the enrolled neonates were recorded. The enrolled infants were followed up to 1 y of CA at three-monthly intervals. During the follow-up, anthropometry, developmental screening by Denver Developmental Screening Test (DDST), and tone assessment by Amiel-Tison scale were done. Developmental Assessment Scale for Indian Infants (DASII) was administered at CA of 12 mo.

RESULTS

Thirty-seven (75.5%) neonates survived to discharge. Survival rate of neonates with birth weight > 750 g and with gestational age ≥ 26 wk was 90.2% and 85.7%, respectively. Amongst those < 750 g or < 26 wk (n = 8), none survived. Abnormal developmental quotient (DQ < 70%) was seen in 6 infants out of 33 infants (18.1%) followed at 1 y of CA.

CONCLUSION

Overall, 3/4^th of ELBW infants survived to discharge and 80% of those who were followed up at 1 y of CA had normal neurodevelopmental outcome. However, survival rates of neonates born at < 26 wk and/or with birth weight < 750 g  were less and needs to be improved.

Impaired pulmonary function mediates inattention in young adults born extremely preterm

AIM

To test whether poor childhood pulmonary function explains the relationship between extremely preterm (EP) birth and attention-deficit/hyperactivity disorder (ADHD) symptoms in young adulthood.

METHODS

EPICure birth cohort participants include children born <26 weeks' gestation in the United Kingdom and Ireland in 1995 and their term-born classmates. Predictor was EP birth. Outcomes were inattention/hyperactivity subscale z-scores at 19 years. Forced expiratory volume (FEV1) z-scores in childhood and young adulthood were mediators. We used recursive path analysis to determine the direct effect of EP birth on inattention/hyperactivity and its indirect effect through pulmonary function.

RESULTS

Ninety EP and 47 term-born participants had pulmonary function testing at 11 and 19 years. Inattention z-scores were higher in the EP group (mean difference 0.55 [95% CI 0.11, 0.99]) but not hyperactivity. Compared to term-born peers, EP participants had lower FEV1 z-scores at 11 (mean difference-1.35 [95% CI -1.72, -0.98]) and 19 (mean difference-1.29 [95% CI -1.65, -0.92]). Path models revealed that childhood pulmonary function explained the relationship between EP birth and inattention.

CONCLUSIONS

Extremely preterm young adults have increased risk for inattention compared to term-born peers. Poor pulmonary function appears to underlie this risk. The mechanisms responsible remain unclear and warrant further study.

Position management on pulmonary function and bronchopulmonary dysplasia in premature infants: study protocol for a randomised controlled trial

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is a common disease caused by various factors and mechanisms in premature infants. Owing to lung hypoplasia and the lack of alveolar surfactants in premature infants, oxygen therapy is often needed to maintain adequate breathing. Nevertheless, prolonged oxygen therapy can easily induce BPD, and there is currently no effective treatment. Therefore, the prevention of BPD in premature infants during hospitalisation is essential. Studies have revealed that the prone position can effectively improve the oxygenation of premature infants. However, a few studies have reported whether prone positioning can improve lung function and reduce BPD incidence. This trial will determine whether the prone position, compared with the supine position, can reduce BPD incidence and improve lung function in preterm infants.

METHODS AND ANALYSIS

This study protocol is for a single-centre, single-blind, randomised controlled trial of the prone position in premature infants. Following daily feeding, premature infants will be placed in the lateral position for 30 min; then they will be turned to the supine position (control group) or prone position (intervention group) for 2 hours each in the morning and afternoon. Moreover, infants in both groups will be placed in the supine or lateral position alternately according to their medical needs for the remaining time. The study begins when the premature infants are stable within 5 days after admission and ends when they are discharged from the hospital or at 36 weeks postmenstrual age. The primary outcome is the survival rate without BPD. The secondary outcomes include lung function parameters and lung oxygen saturation.

ETHICS AND DISSEMINATION

This trial is approved by the ethics committee of the Affiliated Hospital of Southwest Medical University, (ref approval no.KY2021186). The results will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2100049847.

Postnatal corticosteroid use for prevention or treatment of bronchopulmonary dysplasia in England and Wales 2012-2019: a retrospective population cohort study

OBJECTIVE

Describe the population of babies who do and do not receive postnatal corticosteroids for prevention or treatment of bronchopulmonary dysplasia (BPD).

DESIGN

Retrospective cohort study using data held in the National Neonatal Research Database.

SETTING

National Health Service neonatal units in England and Wales.

PATIENTS

Babies born less than 32 weeks gestation and admitted to neonatal units from 1 January 2012 to 31 December 2019.

MAIN OUTCOMES

Proportion of babies given postnatal corticosteroid; type of corticosteroid; age at initiation and duration, trends over time.

SECONDARY OUTCOMES

Survival to discharge, treatment for retinopathy of prematurity, BPD, brain injury, severe necrotising enterocolitis, gastrointestinal perforation.

RESULTS

8% (4713/62019) of babies born <32 weeks and 26% (3525/13527) born <27 weeks received postnatal corticosteroids for BPD. Dexamethasone was predominantly used 5.3% (3309/62019), followed by late hydrocortisone 1.5%, inhaled budesonide 1.5%. prednisolone 0.8%, early hydrocortisone 0.3% and methylprednisolone 0.05%. Dexamethasone use increased over time (2012: 4.5 vs 2019: 5.8%, p=0.04). Median postnatal age of initiation of corticosteroid course was around 3 weeks for late hydrocortisone, 4 weeks for dexamethasone, 6 weeks for inhaled budesonide, 12 weeks for prednisolone and 16 weeks for methylprednisolone. Babies who received postnatal corticosteroids were born more prematurely, had a higher incidence of comorbidities and a longer length of stay.

CONCLUSIONS

In England and Wales, around 1 in 12 babies born less than 32 weeks and 1 in 4 born less than 27 weeks receive postnatal corticosteroids to prevent or treat BPD. Given the lack of convincing evidence of efficacy, challenges of recruiting to and length of time taken to conduct randomised controlled trial, our data highlight the need to monitor long-term outcomes in children who received neonatal postnatal corticosteroids.

Bronchopulmonary dysplasia is not related to neurofilament light for neuroaxonal damage in preterm infants

BACKGROUND

Neurofilament light (NfL) has been identified as a biomarker for neuroaxonal damage in preterm infants, but its relation with bronchopulmonary dysplasia (BPD) has not been established. We hypothesized that BPD is associated with increased NfL levels at an early stage, indicative of early neuroaxonal damage.

METHODS

We included preterm infants born <30 weeks of gestation for assessment of NfL levels from cord blood and blood obtained at postnatal days 3, 7, 14, and 28. We used linear regression analysis to compare NfL levels between infants with moderate/severe BPD and infants with no/mild BPD, and linear mixed model analysis to compare the effect of time on NfL levels between groups.

RESULTS

Sixty-seven infants with a gestational age (GA) of 27 ± 1.3 weeks were included for analysis, of whom 19 (28%) developed moderate/severe BPD. Although NfL levels were higher at every time point in infants with BPD, statistical significance was lost after adjustment for GA, small for gestational age (SGA) and intraventricular hemorrhage (IVH). Groups did not differ in NfL change over time.

CONCLUSIONS

The positive association between BPD and NfL in the first weeks of life could be explained by GA, SGA and IVH rather than by development of BPD.

IMPACT

Neurofilament light chain (NfL) is a known biomarker for neuroaxonal damage. Biomarkers for brain damage during the first weeks of life in preterm infants developing BPD are lacking. NfL levels obtained during the first weeks of life did not differ between infants with and without BPD in analyses adjusted for GA, SGA, and IVH.

High doses of enteral docosahexaenoic acid omega-3 supplementation for prevention of bronchopulmonary dysplasia in very preterm infants: a protocol for a systematic review and meta-analysis

INTRODUCTION

Docosahexaenoic acid (DHA) supplementation in the neonatal period has been proposed to prevent bronchopulmonary dysplasia (BPD) in very preterm infants. We aim to determine the effects of an enteral supplementation with high doses of DHA on the risk for BPD at 36 weeks' postmenstrual age (PMA) in very preterm infants born less than 29 weeks' gestation compared with a control.

METHODS AND ANALYSIS

We will conduct a systematic review and meta-analysis of randomised controlled trials (RCTs) searching PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, MedRxiv, ClinicalTrials.gov (up to 1 November 2021) as well as reference lists and citations of included articles and previous reviews. RCTs targeting infants born less than 29 weeks' gestation and evaluating the effect of high doses of DHA enteral supplementation in the neonatal period compared with a control will be eligible. Primary outcome will be BPD defined as the need for oxygen and/or ventilation at 36 weeks' PMA. Two authors will independently screen for inclusion, extract data and assess data quality using the Cochrane instrument (risk-of-bias tool 2.0). We will perform meta-analysis using random effects models. Prespecified subgroup analyses are planned for the infant gestational age and sex, the marine source of DHA, mode of administration and duration of exposure. Sensitivity analysis will be performed according to the accuracy of the BPD definition (ie, physiological definition) and according to the risk of bias of the RCTs.

ETHICS AND DISSEMINATION

This protocol for a systematic review and meta-analysis does not require ethics approval, as no primary data are collected. This study will assess the effectiveness of high doses of enteral DHA supplementation on BPD and provide evidence to clinicians and families for decision-making. Findings will be disseminated through conferences, media interviews and publications to peer review journals.

PROSPERO REGISTRATION NUMBER

CRD42021286705.

Can serum periostin predict bronchopulmonary dysplasia in premature infants?

BACKGROUND

Bronchopulmonary dysplasia (BPD) is the most common morbidity complicating preterm birth and affects long-term respiratory outcomes. The objectives of this study were to establish whether serum periostin at birth, day of life (DOL) 28, and corrected 36 weeks' gestational age could be potential biomarkers for BPD.

METHODS

A total of 98 preterm Japanese infants born at <32 weeks and comparing 41 healthy controls born at term, were divided into BPD (n = 44) and non-BPD (n = 54) cohorts. Serum periostin levels were measured using an enzyme-linked immunosorbent assay.

RESULTS

Among 98 preterm infants, the median serum periostin levels at birth were higher with BPD (338.0 ng/mL) than without (275.0 ng/mL, P < 0.001). Multivariate analysis revealed that serum periostin levels at birth were significantly associated with BPD (P = 0.013). Serum periostin levels at birth with moderate/severe BPD (345.0 ng/mL) were significantly higher than those with non-BPD/mild BPD (283.0 ng/mL, P = 0.006).

CONCLUSIONS

Serum periostin levels were significantly correlated with birth weight and gestational age, and serum periostin levels at birth in BPD infants were significantly higher than that in non-BPD infants.

IMPACT

This study found higher serum periostin levels at birth in preterm infants subsequently diagnosed with bronchopulmonary dysplasia. It also emerged that serum periostin levels at birth significantly correlated with gestational age and birth weight. The mechanism by which serum periostin is upregulated in BPD infants needs further investigation.

Profiles of Functioning in 5.5-Year-Old Very Preterm Born Children in France: The EPIPAGE-2 Study

OBJECTIVE

Very preterm born children are at risk for impairments in multiple neurodevelopmental domains, but outcomes vary between individuals. The present study aimed to distinguish subgroups with distinct profiles of functioning across motor, cognitive, behavioral, and psychosocial domains. These profiles were related to neonatal and social/environmental factors.

METHOD

The sample included 1977 children born very preterm (<32 weeks' gestation) in 2011 from the French population-based EPIPAGE-2 cohort. Using latent profile analysis, subgroups of children were distinguished based on their functioning at 5.5 years. The relation between outcome profiles and neonatal and social/environmental factors was tested using multivariable multinomial logistic regression analysis.

RESULTS

Four subgroups with distinct outcome profiles were distinguished: no deficit in any domain (45%); motor and cognitive deficits without behavioral/psychosocial deficits (31%); primarily behavioral and psychosocial deficits (16%); and deficits in multiple domains (8%). Male sex (odds ratio [OR] = 2.1-2.7), bronchopulmonary dysplasia (OR = 2.1-2.8), low parental education level (OR = 1.8-2.1), and parental non-European immigrant status (OR = 2.3-3.0) were independently associated with higher odds for all suboptimal outcome profiles compared to the favorable outcome profile.

CONCLUSION

Among 5.5-year-old very preterm born children, subgroups can be distinguished with distinct outcome profiles that vary in severity, type, and combinations of deficits. This information is important for the development of interventions that are tailored to the needs of large subgroups of children across multiple domains of functioning. General neonatal and social/environmental factors may be useful for early identification of very preterm born children at risk for general rather than domain-specific impairments.

Dexamethasone, Prednisolone, and Methylprednisolone Use and 2-Year Neurodevelopmental Outcomes in Extremely Preterm Infants

IMPORTANCE

Practice variability exists in the use of corticosteroids to treat or prevent bronchopulmonary dysplasia in extremely preterm infants, but there is limited information on longer-term impacts.

OBJECTIVE

To describe the use of corticosteroids in extremely preterm infants and evaluate the association with neurodevelopmental outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was a secondary analysis of data from the Preterm Erythropoietin Neuroprotection (PENUT) randomized clinical trial, conducted at 19 participating sites and 30 neonatal intensive care units (NICUs) in the US. Inborn infants born between 24 0/7 and 27 6/7 weeks gestational age between December 2013 and September 2016 were included in analysis. Data analysis was conducted between February 2021 and January 2022.

EXPOSURES

Cumulative dose of dexamethasone and duration of therapy for dexamethasone and prednisolone or methyl prednisolone were evaluated.

MAIN OUTCOMES AND MEASURES

Demographic and clinical characteristics were described in infants who did or did not receive corticosteroids of interest and survived to discharge. Neurodevelopmental outcomes at 2 years of age were evaluated using the Bayley Scales of Infant Development-Third Edition (BSID-III) at corrected age 2 years.

RESULTS

A total of 828 extremely preterm infants (403 [49%] girls; median [IQR] gestational age, 26 [25-27] weeks) born at 19 sites who survived to discharge were included in this analysis, and 312 infants (38%) were exposed to at least 1 corticosteroid of interest during their NICU stay, including 279 exposed to dexamethasone, 137 exposed to prednisolone or methylprednisolone, and 79 exposed to both. Exposed infants, compared with nonexposed infants, had a lower birth weight (mean [SD], 718 [168] g vs 868 [180] g) and were born earlier (mean [SD] gestational age, 25 [1] weeks vs 26 [1] weeks). The median (IQR) start day was 29 (20-44) days for dexamethasone and 53 (30-90) days for prednisolone or methylprednisolone. The median (IQR) total days of exposure was 10 (5-15) days for dexamethasone and 13 (6-25) days for prednisolone or methylprednisolone. The median (IQR) cumulative dose of dexamethasone was 1.3 (0.9-2.8) mg/kg. After adjusting for potential confounders, treatment with dexamethasone for longer than 14 days was associated with worse neurodevelopmental outcomes, with mean scores in BSID-III 7.4 (95% CI, -12.3 to -2.5) points lower in the motor domain (P = .003) and 5.8 (95% CI, -10.9 to -0.6) points lower in the language domain (P = .03), compared with unexposed infants.

CONCLUSIONS AND RELEVANCE

These findings suggest that long duration and higher cumulative dose of dexamethasone were associated with worse neurodevelopmental scores at corrected age 2 years. Potential unmeasured differences in the clinical conditions of exposed vs unexposed infants may contribute to these findings. Improved standardization of treatment and documentation of indications would facilitate replication studies.

Perinatal Hyperoxia and Developmental Consequences on the Lung-Brain Axis

Approximately 11.1% of all newborns worldwide are born preterm. Improved neonatal intensive care significantly increased survival rates over the last decades but failed to reduce the risk for the development of chronic lung disease (i.e., bronchopulmonary dysplasia (BPD)) and impaired neurodevelopment (i.e., encephalopathy of prematurity (EoP)), two major long-term sequelae of prematurity. Premature infants are exposed to relative hyperoxia, when compared to physiological in-utero conditions and, if needed to additional therapeutic oxygen supplementation. Both are associated with an increased risk for impaired organ development. Since the detrimental effects of hyperoxia on the immature retina are known for many years, lung and brain have come into focus in the last decade. Hyperoxia-induced excessive production of reactive oxygen species leading to oxidative stress and inflammation contribute to pulmonary growth restriction and abnormal neurodevelopment, including myelination deficits. Despite a large body of studies, which unraveled important pathophysiological mechanisms for both organs at risk, the majority focused exclusively either on lung or on brain injury. However, considering that preterm infants suffering from BPD are at higher risk for poor neurodevelopmental outcome, an interaction between both organs seems plausible. This review summarizes recent findings regarding mechanisms of hyperoxia-induced neonatal lung and brain injury. We will discuss common pathophysiological pathways, which potentially link both injured organ systems. Furthermore, promises and needs of currently suggested therapies, including pharmacological and regenerative cell-based treatments for BPD and EoP, will be emphasized. Limited therapeutic approaches highlight the urgent need for a better understanding of the mechanisms underlying detrimental effects of hyperoxia on the lung-brain axis in order to pave the way for the development of novel multimodal therapies, ideally targeting both severe preterm birth-associated complications.

Mortality in Outpatients with Bronchopulmonary Dysplasia

OBJECTIVES

To study the demographic and clinical characteristics of preterm infants with bronchopulmonary dysplasia (BPD) to identify the factors most strongly predictive of outpatient mortality, with the goal of identifying those individuals at greatest risk.

STUDY DESIGN

Demographic and clinical characteristics were retrospectively reviewed for 862 subjects recruited from an outpatient BPD clinic. Characteristics of the deceased and living participants were compared using nonparametric analysis. Regression analysis was performed to identify factors associated with mortality.

RESULTS

Of the 862 subjects, 13 (1.5%) died during follow-up, for an overall mortality rate of approximately 15.1 deaths per 1000 subjects. Two patients died in the postneonatal period (annual mortality incidence, 369.9 per 100 000), 9 died between age 1 and 4 years (annual mortality incidence, 310.2 per 100 000), and 2 died between age of 5 and 14 years (annual mortality incidence, 71.4 per 100 000). After adjusting for gestational age and BPD severity, mortality was found to be associated with the amount of supplemental oxygen required at discharge from the neonatal intensive care unit (adjusted hazard ratio [aHR], 4.10; P = .001), presence of a gastrostomy tube (aHR, 8.13; P = .012), and presence of a cerebrospinal fluid (CSF) shunt (aHR, 4.31; P = .021).

CONCLUSIONS

The incidence of mortality among preterm infants with BPD is substantially higher than that seen in the general population. The need for greater amounts of home supplemental oxygen and the presence of a gastrostomy tube or CSF shunt were associated with an increased risk of postdischarge mortality. Future studies should focus on clarifying risk factors for the development of severe disease to allow for early identification and treatment of those at highest risk.

Volumetric Capnography at 36 Weeks Postmenstrual Age and Bronchopulmonary Dysplasia in Very Preterm Infants

OBJECTIVES

To assess the feasibility of volumetric capnography in spontaneously breathing very preterm infants at 36 weeks postmenstrual age (PMA) and its association with clinical markers of lung disease including the duration of respiratory support and bronchopulmonary dysplasia (BPD).

STUDY DESIGN

We obtained mainstream volumetric capnography measurements in 143 very preterm infants at 36 weeks PMA. BPD was categorized into no, mild, moderate, and severe according to the 2001 National Heart, Lung and Blood Institute workshop report. Normalized capnographic slopes of phase II (S_nII) and phase III (S_nIII) were calculated. We assessed the effect of BPD, duration of respiratory support, and duration of supplemental oxygen on capnographic slopes.

RESULTS

S_nIII was steeper in infants with moderate to severe BPD (76 ± 25/L) compared with mild (31 ± 20/L) or no BPD (26 ± 18/L) (P < .001). The association of S_nIII with moderate to severe BPD persisted after adjusting for birth weight z-score, respiratory rate, and airway dead space to tidal volume ratio. The diagnostic usefulness of S_nIII to discriminate between infants with and without moderate to severe BPD was high (area under the curve, 0.94; 95% CI, 0.89-0.99).

CONCLUSIONS

Volumetric capnography is feasible in spontaneously breathing preterm infants at 36 weeks PMA and reflects the degree of lung disease. This promising bedside lung function technique may offer an objective, continuous physiological outcome measure for assessment of BPD severity.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02083562.

Respiratory morbidity in preterm infants predicted by natriuretic peptide (MR-proANP) and endothelin-1 (CT-proET-1)

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a major complication in preterm infants <32 weeks. We aimed to assess whether plasma levels of mid-regional pro-atrial natriuretic peptide (MR-proANP) and C-terminal pro-endothelin-1 (CT-proET-1) predict respiratory morbidity.

METHODS

This was a prospective, two-center, observational cohort study. MR-proANP and CT-proET-1 were measured at day 7 (±2) of life. Associations with duration of supplemental oxygen and the composite outcome of moderate or severe BPD or death (BPD/death) were investigated.

RESULTS

Two hundred and twenty-nine infants <32 weeks were included (median gestational age [GA] 29.6 weeks [interquartile range 29.0-30.7], median birth weight 1150 g [IQR 840-1410]). MR-proANP and CT-proET-1 were associated with the duration of supplemental oxygen in univariable analysis (both p < 0.001) but not after adjusting for co-factors. Infants with BPD/death showed higher plasma levels of MR-proANP (623.50 pmol/L [IQR 458.50-881.38] vs. 308.35 pmol/L [IQR 216.72-538.10]; p < 0.001) and CT-proET-1 (255.40 pmol/L [IQR 202.60-311.15] vs. 198.30 pmol/L [IQR 154.70-297.95]; p = 0.015) compared to infants without BPD/death. Levels of both biomarkers were significantly associated with BPD/death in univariable models but not after adjusting for co-factors.

CONCLUSIONS

MR-proANP and CT-proET-1 are associated with the duration of supplemental oxygen and the composite outcome BPD/death, but their prognostic value does not complement that of clinical risk factors.

IMPACT

Plasma levels of MR-proANP and CT-proET-1, measured on day 7 of life (±2 days) are associated in univariable analyses with duration of supplemental oxygen and the combined outcome of BPD or death in VLGA infants. Associations between both biomarkers and respiratory morbidity do not persist in multivariable models, in particular when gestational age is included. MR-proANP and CT-proET-1 have limited additional value to predict respiratory morbidity in VLGA infants compared to clinical parameters.

Shape variability of the central sulcus in the developing brain: a longitudinal descriptive and predictive study in preterm infants

Despite growing evidence of links between sulcation and function in the adult brain, the folding dynamics, occurring mostly before normal-term-birth, is vastly unknown. Looking into the development of cortical sulci in infants can give us keys to address fundamental questions: what is the sulcal shape variability in the developing brain? When are the shape features encoded? How are these morphological parameters related to further functional development? In this study, we aimed to investigate the shape variability of the developing central sulcus, which is the frontier between the primary somatosensory and motor cortices. We studied a cohort of 71 extremely preterm infants scanned twice using MRI - once around 30 weeks post-menstrual age (w PMA) and once at term-equivalent age, around 40w PMA -, in order to quantify the sulcus's shape variability using manifold learning, regardless of age-group or hemisphere. We then used these shape descriptors to evaluate the sulcus's variability at both ages and to assess hemispheric and age-group specificities. This led us to propose a description of ten shape features capturing the variability in the central sulcus of preterm infants. Our results suggested that most of these features (8/10) are encoded as early as 30w PMA. We unprecedentedly observed hemispheric asymmetries at both ages, and the one captured at term-equivalent age seems to correspond with the asymmetry pattern previously reported in adults. We further trained classifiers in order to explore the predictive value of these shape features on manual performance at 5 years of age (handedness and fine motor outcome). The central sulcus's shape alone showed a limited but relevant predictive capacity in both cases. The study of sulcal shape features during early neurodevelopment may participate to a better comprehension of the complex links between morphological and functional organization of the developing brain.

Double Jeopardy: Prematurity and Congenital Heart Disease-What's Known and Why It's Important

This article is based on a composite of talks presented during the Double Jeopardy: Prematurity and Congenital Heart Disease Plenary Session at NeoHeart 2020, a global virtual conference.Prematurity and low weight remain significant risk factors for mortality after neonatal cardiac surgery despite a steady increase in survival. Newer and lower weight thresholds for operability are constantly generated as surgeons gather proficiency, technical mastery, and experience in performing complex procedures on extremely small infants. The relationship between birth weight and survival after cardiac surgery is nonlinear with 2 kilograms (kg) being an inflection point below which marked decline in survival occurs.The prevalence of congenital heart disease (CHD) in premature infants is more than twice that in term born infants. Increased risk of preterm birth in infants with CHD is most commonly due to spontaneous preterm birth and remains poorly understood.Advances in Neonatal-Perinatal medicine have led to a marked improvement in survival of neonates born prematurely over the last several decades. However, the risk of severe morbidities including retinopathy of prematurity, intraventricular hemorrhage, bronchopulmonary dysplasia and necrotizing enterocolitis remains significant in extremely low birth weight infants. Premature infants with CHD are at a greater risk of prematurity related morbidities than premature infants without CHD. Interventions that have been successful in decreasing the risk of these morbidities are addressed.

Metabolic analysis of infants with bronchopulmonary dysplasia under early nutrition therapy: An observational cohort study

To assess the amino acid and fatty acid metabolite patterns between infants with and without bronchopulmonary dysplasia in different nutritional stages after birth and identify metabolic indicators of bronchopulmonary dysplasia. This was an observational cohort of preterm infants born at a gestational age ≤32 + 6 weeks and with a body weight ≤2000 g. Amino acid and carnitine profiles were measured in dried blood spots (DBSs) during the early nutrition transitional phase using tandem mass spectrometry. Bronchopulmonary dysplasia was defined as oxygen dependence at 36 weeks of postmenstrual age or 28 days after birth. Metabolomic analysis was employed to define metabolites with significant differences, map significant metabolites into pathways, and identify metabolic indicators of bronchopulmonary dysplasia. We evaluated 45 neonates with and 40 without bronchopulmonary dysplasia. Four amino acids and three carnitines showed differences between the groups. Three carnitines (C0, C2, and C6:1) were high in the bronchopulmonary dysplasia group mostly; conversely, all four amino acids (threonine, arginine, methionine, and glutamine (Gln)) were low in the bronchopulmonary dysplasia group. Pathway analysis of these metabolites revealed two pathways with significant changes (p < 0.05). ROC analysis showed Gln/C6:1 at total parenteral nutrition phase had both 80% sensitivity and specificity for predicting the development of bronchopulmonary dysplasia, with an area under the curve of 0.81 (95% confidence interval 0.71-0.89). Amino acid and fatty acid metabolite profiles changed in infants with bronchopulmonary dysplasia after birth during the nutrition transitional period, suggesting that metabolic dysregulation may participate in the development of bronchopulmonary dysplasia. Our findings demonstrate that metabolic indicators are promising for forecasting the occurrence of bronchopulmonary dysplasia among preterm neonates.

Association of Severe Retinopathy of Prematurity and Bronchopulmonary Dysplasia with Adverse Neurodevelopmental Outcomes in Preterm Infants without Severe Brain Injury

Although impaired neurodevelopment is strongly associated with severe brain injury, most preterm infants survive without severe brain injury. In this study, the association of impaired neurodevelopment and neonatal morbidities of preterm infants was assessed after excluding those with severe brain injury. This was a retrospective study of very low birthweight infants in a single tertiary center. After excluding infants with severe brain injury, the study population was categorized as infants without intraventricular hemorrhage (IVH) and with low-grade IVH. Neurodevelopmental outcomes at a corrected age (CA) of 18-24 months were evaluated using the Bayley Scales of Infant and Toddler Development 3rd Edition (Bayley-III). Cerebral palsy (CP), hearing impairment and blindness were also assessed and compared. Of 240 infants, 25 (11.6%) infants had combined neurodevelopmental impairment (NDI). In the multivariate analysis for combined NDI, small for gestational age (SGA) (adjusted OR 6.820, 95% confidence intervals (CI) 1.770-26.307), moderate to severe bronchopulmonary dysplasia (BPD) (aOR 3.21, 95% CI 1.032-9.999) and severe retinopathy of prematurity (ROP) (aOR 5.669, 95% CI 1.132-28.396) were associated with combined NDI. Among neonatal morbidities, moderate to severe BPD and severe ROP were associated with adverse neurodevelopmental outcomes in preterm infants without severe brain injury.

Surfactant protein D and bronchopulmonary dysplasia: a new way to approach an old problem

Surfactant protein D (SP-D) is a collectin protein synthesized by alveolar type II cells in the lungs. SP-D participates in the innate immune defense of the lungs by helping to clear infectious pathogens and modulating the immune response. SP-D has shown an anti-inflammatory role by down-regulating the release of pro-inflammatory mediators in different signaling pathways such as the TLR4, decreasing the recruitment of inflammatory cells to the lung, and modulating the oxidative metabolism in the lungs. Recombinant human SP-D (rhSP-D) has been successfully produced mimicking the structure and functions of native SP-D. Several in vitro and in vivo experiments using different animal models have shown that treatment with rhSP-D reduces the lung inflammation originated by different insults, and that rhSP-D could be a potential treatment for bronchopulmonary dysplasia (BPD), a rare disease for which there is no effective therapy up to date. BPD is a complex disease in preterm infants whose incidence increases with decreasing gestational age at birth. Lung inflammation, which is caused by different prenatal and postnatal factors like infections, lung hyperoxia and mechanical ventilation, among others, is the key player in BPD. Exacerbated inflammation causes lung tissue injury that results in a deficient gas exchange in the lungs of preterm infants and frequently leads to long-term chronic lung dysfunction during childhood and adulthood. In addition, low SP-D levels and activity in the first days of life in preterm infants have been correlated with a worse pulmonary outcome in BPD. Thus, SP-D mediated functions in the innate immune response could be critical aspects of the pathogenesis in BPD and SP-D could inhibit lung tissue injury in this preterm population. Therefore, administration of rhSP-D has been proposed as promising therapy that could prevent BPD.

Hyperoxia-activated circulating extracellular vesicles induce lung and brain injury in neonatal rats

Hyperoxia-induced lung injury plays a key role in the development of bronchopulmonary dysplasia (BPD), characterized by inflammatory injury and impaired lung development in preterm infants. Although BPD is a predictor of poor neurodevelopmental outcomes, currently it is uncertain how lung injury contributes to brain injury in preterm infants. Extracellular vesicles (EVs) are a heterogeneous group of cell-derived membranous structures that regulate intercellular and inter-organ communications. Gasdermin D (GSDMD) has emerged as a key executor of inflammasome-mediated cell death and inflammation. In this study, we utilized a neonatal rat model of BPD to assess if hyperoxia stimulates lung release of circulating EVs and if these EVs induce lung and brain injury. We found that hyperoxia-exposed rats had elevated numbers of plasma-derived EVs compared to rats maintained in room air. These EVs also had increased cargos of surfactant protein C, a marker of type II alveolar epithelial cells (AEC), and the active (p30) form of GSDMD. When these EVs were adoptively transferred into normal newborn rats via intravenous injection, they were taken up both by lung and brain tissues. Moreover, EVs from hyperoxic animals induced not only the pathological hallmarks of BPD, but also brain inflammatory injury in recipient rats, as well as inducing cell death in cultured pulmonary vascular endothelial cells and neural stem cells (NSC). Similarly, hyperoxia-exposed cultured AEC-like cells released EVs that also contained increased GSDMD-p30 and these EVs induced pyroptotic cell death in NSC. Overall, these data indicate that hyperoxia-activated circulating EVs mediate a lung to brain crosstalk resulting in brain injury and suggest a mechanism that links lung injury and neurodevelopmental impairment in BPD infants.

Survival of Ventilated Extremely Premature Neonates With Severe Intraventricular Hemorrhage

BACKGROUND

Severe intraventricular hemorrhage (IVH) is a leading mortality risk factor among extremely premature neonates. Because other life-threatening conditions also occur in this population, it is unclear whether severe IVH is independently associated with death. The existence and potential implications of regional variation in severe IVH-associated mortality are unknown.

METHODS

We performed a retrospective cohort study of mechanically ventilated neonates born at 22 to 29 weeks' gestation who received care in 242 American NICUs between 2000 and 2014. After building groups composed of propensity score-matched and center-matched pairs, we used the Cox proportional hazards analysis to test our hypothesis that severe IVH would be associated with greater all-cause in-hospital mortality, defined as death before transfer or discharge. We also performed propensity score-matched subgroup analyses, comparing severe IVH-associated mortality among 4 geographic regions of the United States.

RESULTS

In our analysis cohort, we identified 4679 patients with severe IVH. Among 2848 matched pairs, those with severe IVH were more likely to die compared with those without severe IVH (hazard ratio 2.79; 95% confidence interval 2.49-3.11). Among 1527 matched pairs still hospitalized at 30 days, severe IVH was associated with greater risk of death (hazard ratio 2.03; 95% confidence interval 1.47-2.80). Mortality associated with severe IVH varied substantially between geographic regions.

CONCLUSIONS

The early diagnosis of severe IVH is independently associated with all-cause in-hospital mortality in extremely premature neonates. Regional variation in severe IVH-associated mortality suggests that shared decision-making between parents and neonatologists is strongly influenced by ultrasound-based IVH assessment and classification.

Revisiting the definition of bronchopulmonary dysplasia in premature infants at a single center quaternary neonatal intensive care unit

OBJECTIVE

To compare the incidence of bronchopulmonary dysplasia (BPD) based on the 1988 Vermont Oxford Network (VON) criteria, National Institutes of Health (NIH) 2001 definition, and NIH 2018 definition.

METHODS

BPD incidence by each definition was compared in premature infants born at a single center between 2016 and 2018. Comorbidities were compared between those with and without BPD according to the newest definition.

RESULTS

Among 352 survivors, BPD incidence was significantly different at 9%, 28% and 34% according to VON, NIH 2001 and NIH 2018 definitions, respectively (p < 0.05). According to the newest definition, any grade of BPD was associated with more co-morbidities than those without BPD (P < 0.001).

CONCLUSION

At a center that emphasizes use of early noninvasive respiratory support, the incidence of BPD was significantly higher according to the NIH 2018 definition compared to other two definitions. The relationship between BPD diagnosis and long-term clinical outcomes remains unclear.

Red cell distribution width as a predictor for bronchopulmonary dysplasia in premature infants

Bronchopulmonary dysplasia (BPD) is the most common morbidity complicating preterm birth. Red blood cell distribution width (RDW), a measure of the variation of red blood cell size, could reflect oxidative stress and chronic inflammation in many diseases such as cardiovascular, pulmonary, and other diseases. The objectives of the present study were to evaluate perinatal factors affecting RDW and to validate whether RDW could be a potential biomarker for BPD. A total of 176 preterm infants born at < 30 weeks were included in this study. They were categorized into BPD (n = 85) and non-BPD (n = 91) infants. RDW at birth and 14 days and 28 days of life (DOL 14, DOL 28) were measured. Clinical data were obtained from all subjects at Fukushima Medical University (Fukushima, Japan). The mean RDW at birth, DOL 14 and DOL 28 were 16.1%, 18.6%, 20.1%, respectively. Small for gestational age (SGA), chorioamnionitis (CAM), hypertensive disorders of pregnancy (HDP), gestational age and birth weight were significantly associated with RDW at birth. SGA, BPD and red blood cell (RBC) transfusion before DOL 14 were associated with RDW at DOL 14. BPD and RBC transfusion before DOL 14 were associated with RDW at DOL 28. Compared with non-BPD infants, mean RDW at DOL 14 (21.1% vs. 17.6%, P < 0.001) and DOL 28 (22.2% vs. 18.2%, P < 0.001) were significantly higher in BPD infants. Multivariate analysis revealed that RDW at DOL 28 was significantly higher in BPD infants (P = 0.001, odds ratio 1.63; 95% CI 1.22–2.19). Receiver operating characteristic analysis for RDW at DOL 28 in infants with and without BPD yielded an area under the curve of 0.87 (95% CI 0.78–0.91, P < 0.001). RDW at DOL 28 with mild BPD (18.1% vs. 21.3%, P < 0.001), moderate BPD (18.1% vs. 21.2%, P < 0.001), and severe BPD (18.1% vs. 24.0%, P < 0.001) were significantly higher than those with non-BPD, respectively. Furthermore, there are significant differences of RDW at DOL 28 among mild, moderate, and severe BPD. In summary, we conclude that RDW at DOL 28 could serve as a biomarker for predicting BPD and its severity. The mechanism by which RDW at DOL 28 is associated with the pathogenesis of BPD needs further elucidation.

Biomarker Potential of the Soluble Receptor for Advanced Glycation End Products to Predict Bronchopulmonary Dysplasia in Premature Newborns

Bronchopulmonary dysplasia (BPD) is a common cause of pulmonary disease in preterm infants. The soluble receptor for advanced glycation end products (sRAGE) is implicated in the development of various pulmonary diseases. The objectives of the current study were to investigate perinatal factors associated with serum sRAGE levels at birth and to establish whether serum sRAGE could be a biomarker for BPD. This retrospective single-center study was conducted at Fukushima Medical University Hospital's Department of Pediatrics Neonatal Intensive Care Unit from April 2014 to September 2020. Mechanically ventilated or oxygenated neonates born at <32 weeks gestational age and healthy control neonates were included in this study. Serum sRAGE levels in cord blood were measured using an enzyme-linked immunosorbent assay. Eighty-four preterm infants born at <32 weeks and 40 healthy infants were identified. The 84 born at <32 weeks were categorized as BPD (n = 34) or non-BPD (n = 50) neonates. The median gestational age (GA) and birthweight (BW) were significantly lower in BPD vs. non-BPD neonates (24.4 vs. 27.6 weeks, P < 0.001, 634 vs. 952 g, P < 0.001, respectively). Serum sRAGE at birth in all 124 preterm and term infants significantly correlated with BW (r = 0.417, P < 0.0001) and GA (r = 0.415, P < 0.0001). Among those born at <32 weeks, median serum sRAGE levels at birth were significantly lower in infants with BPD than without (1,726 vs. 2,797 pg/mL, P = 0.0005). Receiver operating characteristic analysis for sRAGE levels at birth in infants with and without BPD revealed that the area under the curve was 0.724 (95% confidence interval 0.714-0.834, P = 0.001). However, serum RAGE levels were not associated with severity of BPD. Serum sRAGE levels at birth were significantly correlated with BW and GA. Furthermore, serum sRAGE levels at birth could serve as a biomarker for predicting BPD, but not its severity.

Transcutaneous carbon dioxide pattern and trend over time in preterm infants

BACKGROUND

Chronic lung disease remains a burden for extremely preterm infants. The changes in ventilation over time and optimal ventilatory management remains unknown. Newer, non-invasive technologies provide insight into these patterns.

METHODS

This single-center prospective cohort study enrolled infants ≤32 0/7 weeks. We obtained epochs of transcutaneous carbon dioxide (TcCO₂) measurements twice each week to describe the pattern of hypercarbia throughout their hospitalization.

RESULTS

Patterns of hypercarbia varied based on birth gestational age and post-menstrual age (PMA) (p = 0.03), regardless of respiratory support. Infants receiving the most respiratory support had values 16-21 mmHg higher than those on room air (p < 0.001). Infants born at the youngest gestational ages had the greatest total change but the rate of change was slower (p = 0.049) compared to infants born at later gestational ages. All infants had TcCO₂ values stabilize by 31-33 weeks PMA, when values were not significantly different compared to discharge. No rebound was observed when infants weaned off invasive support.

CONCLUSIONS

Hypercarbia improves as infants approached 31-33 weeks PMA. Hypercarbia was the highest in the most immature infants and improved with age and growth despite weaning respiratory support.

IMPACT

This study describes the evolution of hypercarbia as very preterm infants grow and develop. The pattern of ventilation is significantly different depending on the gestational age at birth and post-menstrual age. Average transcutaneous carbon dioxide (TCO₂) decreased over time as infants became more mature despite weaning respiratory support. This improvement was most significant in infants born at the lowest gestational ages.

A Systematic Review of the Influence of Continuous Positive Airway Pressure on Fetal and Newborn Animal Models: Suggestions to Improve Neonatal Respiratory Care

INTRODUCTION

Prematurely born infants regularly develop respiratory distress syndrome and require assisted ventilation. Ventilation may injure the premature lung and increase the risk of bronchopulmonary dysplasia. Continuous positive airway pressure (CPAP), a form of noninvasive ventilation, is commonly used in modern neonatology. Limited clinical data are available on the acute and long-term effect of neonatal exposure to CPAP on the lung. Given the restricted clinical data, newborn animal models have been used to study the influence of CPAP on lung structure and function. The findings of animal studies can guide neonatal care and improve the use of CPAP.

METHODS

A systematic review of electronic databases (Medline, Embase, and Cinahl) was performed using the medical subject heading terms, "CPAP" or "continuous positive airway pressure" and "animals" and "newborn." Abstracts were screened for inclusion using predetermined eligibility criteria.

RESULTS

In total, 235 abstracts were identified and screened for inclusion. Of these, 21 papers were included. Large (N = 18) and small (N = 3) animal models investigated the effects of CPAP. Pulmonary outcomes included gas exchange, lung structure and function, surfactant metabolism, lung inflammation and injury, and the effect of intrapulmonary therapy. Compared to mechanical ventilation, CPAP improves lung function, evokes less lung injury, and does not disrupt alveolar development. Surfactant administration combined with CPAP further improves respiratory outcomes. Of concern are findings that CPAP may increase airway reactivity.

DISCUSSION/CONCLUSION

CPAP offers numerous advantages over mechanical ventilation for the immature lung. The combination of CPAP and exogenous surfactant administration offers further pulmonary benefit.

Differences in Comorbidities and Clinical Burden of Severe Bronchopulmonary Dysplasia Based on Disease Severity

Background: The present study compared baseline characteristics, comorbidities and clinical burden of pre-term infants with type 1 and 2 severe bronchopulmonary dysplasia (BPD) Collaborative classification. Methods: This study was a prospective cohort study of pre-term (<32 weeks) very-low-birth-weight infants. Severe BPD was divided into type 1 severe BPD requiring of ≥30% oxygen and/or non-invasive ventilation at 36 weeks post-menstrual age (PMA), and type 2 severe BPD requiring invasive mechanical ventilation at 36 weeks PMA. Baseline characteristics, comorbidities, and clinical burden were compared between these two types of severe BPD. Results: Of the 1,328 infants included, 983 (74.0%) developed type 1 severe BPD, and 345 (26.0%) developed type 2 severe BPD. Lower birth weight, small for gestational age, lesser maternal pre-mature rupture of membrane, lower 5-min Apgar score, air leak, pulmonary hemorrhage, surgical ligation of patent ductus arteriosus, necrotizing enterocolitis, and late-onset sepsis were significantly associated with type 2 severe BPD. Compared with infants with type 1 severe BPD, infants with type 2 severe BPD had an increased risk of mortality (aOR 18.64, 95% CI 10.81-32.13), pulmonary hypertension (aOR 2.16, 95% CI 1.59-2.93), and tracheostomy (aOR 10.38, 95% CI 2.05-52.49). Conclusions: Our data highlight the substantially greater mortality and clinical burden in infants with type 2 severe BPD than infants with type 1 severe BPD. A comprehensive and multidisciplinary approach is needed for infants with type 2 severe BPD.

Introduction of a Quality Improvement Bundle Is Associated with Reduced Exposure to Mechanical Ventilation in Very Preterm Infants

INTRODUCTION

Exposure to mechanical ventilation (MV) is a risk factor for bronchopulmonary dysplasia (BPD) in very preterm infants (VPTIs). We assessed the impact of a quality improvement (QI) bundle in VPTIs (<32 week gestation) on exposure to MV.

METHODS

We introduced a QI bundle consisting of deferred cord clamping (DCC), nasal bubble continuous positive airway pressure (bCPAP) in the delivery room (DR), and minimally invasive surfactant therapy (MIST). We compared respiratory outcomes and neonatal morbidity in historical pre-QI (July-December 2017) and prospective post-QI (February-July 2019) cohorts (QICs) of VPTIs. We pre-specified an adjusted analysis to account for the effects of gestational age, sex, antenatal steroids, and any demographic data that significantly differed between cohorts.

RESULTS

The pre-QI and post-QICs included 87 and 98 VPTIs, respectively. The post-QIC had decreased rates of MV in the DR (adjusted odds ratio [aOR] 0.26, 95% confidence interval [CI] 0.09-0.71), in the first 72 h of life (aOR 0.27, 95% CI 0.11-0.62) and during admission (aOR 0.28, 95% CI 0.12-0.66). Rates of BPD, combined BPD/death, and BPD severity were similar. The post-QIC was less likely to be discharged with home oxygen (aOR 0.27, 95% CI 0.08-0.91). Necrotising enterocolitis grade ≥2 increased (aOR 19.01, 95% CI 1.93-188.6) in the post-QIC.

CONCLUSION

In this rapid-cycle QI study, implementation of a QI bundle consisting of DCC, early nasal bCPAP, and MIST in VPTIs was associated with reduced rates of MV in the DR, in the first 72 h of life and during admission, and reduced need for home oxygen.

Early cortical maturation predicts neurodevelopment in very preterm infants

OBJECTIVE

To evaluate the ability of four objectively defined, cortical maturation features-surface area, gyrification index, sulcal depth and curvature-from structural MRI at term-equivalent age (TEA) to independently predict cognitive and language development at 2 years corrected age in very preterm (VPT) infants.

DESIGN

Population-based, prospective cohort study. Structural brain MRI was performed at term, between 40 and 44 weeks postmenstrual age and processed using the developing Human Connectome Project pipeline.

SETTING

Multicentre study comprising four regional level III neonatal intensive care units in the Columbus, Ohio region.

PATIENTS

110 VPT infants (gestational age (GA) ≤ 31 weeks).

MAIN OUTCOME MEASURES

Cognitive and language scores at 2 years corrected age on the Bayley Scales of Infant and Toddler Development, Third Edition.

RESULTS

Of the 94 VPT infants with high-quality T2-weighted MRI scans, 75 infants (80%) returned for Bayley-III testing. Cortical surface area was positively correlated with cognitive and language scores in nearly every brain region. Curvature of the inner cortex was negatively correlated with Bayley scores in the frontal, parietal and temporal lobes. In multivariable regression models, adjusting for GA, sex, socioeconomic status, and injury score on MRI, regional measures of surface area and curvature independently explained more than one-third of the variance in cognitive and language scores at 2 years corrected age in our cohort.

CONCLUSIONS

We identified increased cortical curvature at TEA as a new prognostic biomarker of adverse neurodevelopment in very premature infants. When combined with cortical surface area, it enhanced prediction of cognitive and language development. Larger studies are needed to externally validate our findings.

Early neurobehavior at 30 weeks postmenstrual age is related to outcome at term equivalent age

AIMS

To determine 1) the relationship between infant medical factors and early neurobehavior, and 2) the relationship between early neurobehavior at 30 weeks postmenstrual age (PMA) and neurobehavior at term equivalent age.

STUDY DESIGN

In this prospective longitudinal study, 88 very preterm infants born ≤30 weeks estimated gestational age (EGA) had neurobehavioral assessments at 30 weeks PMA using the Premie-Neuro and at term equivalent age using the NICU Network Neurobehavioral Scale (NNNS) and Hammersmith Neonatal Neurological Evaluation (HNNE).

RESULTS

Lower Premie-Neuro scores at 30 weeks PMA were related to being more immature at birth (p = 0.01; β = 3.87); the presence of patent ductus arteriosus (PDA; p < 0.01; β = -16.50) and cerebral injury (p < 0.01; β = -20.46); and prolonged exposure to oxygen therapy (p < 0.01; β = -0.01), endotracheal intubation (p < 0.01; β = -0.23), and total parenteral nutrition (p < 0.01; β = -0.35). After controlling for EGA, PDA, and number of days of endotracheal intubation, lower Premie-Neuro scores at 30 weeks PMA were independently related to lower total HNNE scores at term (p < 0.01; β = 0.12) and worse outcome on the NNNS with poorer quality of movement (p < 0.01; β = 0.02) and more stress (p < 0.01; ß = -0.004), asymmetry (p = 0.01; β = -0.04), excitability (p < 0.01; β = -0.05) and suboptimal reflexes (p < 0.01; ß = -0.06).

CONCLUSION

Medical factors were associated with early neurobehavioral performance at 30 weeks PMA. Early neurobehavior at 30 weeks PMA was a good marker of adverse neurobehavior at NICU discharge.

[A clinical analysis of neurobehavioral development within one year after birth in preterm infants with bronchopulmonary dysplasia]

OBJECTIVE

To study the effect of bronchopulmonary dysplasia (BPD) on neurobehavioral development within one year after birth in preterm infants.

METHODS

A retrospective analysis was performed for the preterm infants with a gestational age of <34 weeks who were born from September 2017 to December 2019 and completed the follow-up assessments of neurobehavioral development at the corrected gestational ages of 40 weeks and 3, 6, and 12 months. According to their diagnosis, they were divided into a BPD group with 23 infants and a non-BPD group with 27 infants. The outcome of neurobehavioral development was compared between the two groups at different time points.

RESULTS

There was no significant difference in the neonatal behavioral neurological assessment score between the BPD and non-BPD groups at the corrected gestational age of 40 weeks (P>0.05). Based on the Gesell Developmental Scale, compared with the non-BPD group, the BPD group had significantly lower global developmental quotient (DQ) and DQs of fine motor, adaptive behavior, and personal-social behavior at the corrected gestational ages of 3, 6, and 12 months (P<0.05). For both groups, the DQ of language at the corrected gestational age of 6 months was significantly higher than that at the corrected gestational age of 12 months (P<0.017), the DQ of personal-social behavior at the corrected gestational age of 6 months was significantly higher than that at the corrected gestational age of 3 months (P<0.017), and the DQ of adaptive behavior at the corrected gestational age of 12 months was significantly higher than that at the corrected gestational ages of 3 and 6 months (P<0.017). Based on the BSID-II scale, there were no significant differences in mental development index and psychomotor development index at each time point between the two groups (P>0.05). The mental development index at the corrected gestational age of 3 months was significantly higher than that at the corrected gestational ages of 6 and 12 months in both groups (P<0.001).

CONCLUSIONS

Preterm infants with BPD have delayed neurodevelopment within one year after birth compared with those without BPD, which should be taken seriously in clinical practice.

The application value of lung ultrasound findings in preterm infants with bronchopulmonary dysplasia

BACKGROUND

The purpose of this study was to investigate the association between ultrasound findings and preterm infants with bronchopulmonary dysplasia (BPD).

METHODS

Preterm infants with a gestation age of less than 28 weeks or birthweight less than 1,500 g admitted to the neonatal intensive care unit (NICU) in the Chengdu Women's & Children's Central Hospital from June 2018 to June 2019 were enrolled in the study and divided into 2 groups: the BPD group and the non-BPD group. All clinical data and lung ultrasound were retrospectively analyzed.

RESULTS

A total of 81 neonates (gestational age =29.71±2.27 weeks; birth weight =1,189.5±184.5 g) were enrolled in our center. The regression analysis showed that gestational age [odds ratio (OR) =0.57; 95% confidence interval (CI): 0.42-0.77, P=0.0002], birthweight (OR =0.99; 95% CI: 0.99-1.00, P<0.0001), mild asphyxia (OR =3.3; 95% CI: 1.24-8.74, P=0.0165), anemia (OR =4.43; 95% CI: 1.34-14.64, P=0.0146), blood transfusion (OR =3.68; 95% CI: 1.38-9.79, P=0.0090), respiratory failure (OR =6.58; 95% CI: 1.27-34.08, P=0.0486), heart failure (OR =6.58; 95% CI: 1.27-34.08, P=0.0248), and "debris" lung ultrasound findings (OR =21.82; 95% CI: 2.63-181.11, P=0.0043) were correlated with BPD.

CONCLUSIONS

BPD-related lung ultrasound findings can be a kind of imaging marker to diagnose BPD.

Behavior Profiles at 2 Years for Children Born Extremely Preterm with Bronchopulmonary Dysplasia

OBJECTIVE

To characterize behavior of 2-year-old children based on the severity of bronchopulmonary dysplasia (BPD).

STUDY DESIGN

We studied children born at 22-26 weeks of gestation and assessed at 22-26 months of corrected age with the Child Behavior Checklist (CBCL). BPD was classified by the level of respiratory support at 36 weeks of postmenstrual age. CBCL syndrome scales were the primary outcomes. The relationship between BPD grade and behavior was evaluated, adjusting for perinatal confounders. Mediation analysis was performed to evaluate whether cognitive, language, or motor skills mediated the effect of BPD grade on behavior.

RESULTS

Of 2310 children, 1208 (52%) had no BPD, 806 (35%) had grade 1 BPD, 177 (8%) had grade 2 BPD, and 119 (5%) had grade 3 BPD. Withdrawn behavior (P < .001) and pervasive developmental problems (P < .001) increased with worsening BPD grade. Sleep problems (P = .008) and aggressive behavior (P = .023) decreased with worsening BPD grade. Children with grade 3 BPD scored 2 points worse for withdrawn behavior and pervasive developmental problems and 2 points better for externalizing problems, sleep problems, and aggressive behavior than children without BPD. Cognitive, language, and motor skills mediated the effect of BPD grade on the attention problems, emotionally reactive, somatic complaints, and withdrawn CBCL syndrome scales (P values < .05).

CONCLUSIONS

BPD grade was associated with increased risk of withdrawn behavior and pervasive developmental problems but with decreased risk of sleep problems and aggressive behavior. The relationship between BPD and behavior is complex. Cognitive, language, and motor skills mediate the effects of BPD grade on some problem behaviors.

Evaluation of cerebral oxygenation and perfusion in small for gestational age neonates and neurodevelopmental outcome at 24-36 months of age

Objective To examine cerebral oxygenation and perfusion in small for gestational age (SGA) compared with appropriate for gestational age (AGA) neonates during the first postnatal week, and to investigate any association with neurodevelopmental outcomes at 24-36 months of age. Methods A prospective matched case-control study was conducted evaluating cerebral oxygenation and perfusion, using near-infrared spectroscopy (NIRS), between SGA and AGA neonates, during the first postnatal week. A neurodevelopmental assessment with Bayley-III was performed at 24-36 months of age. Results Forty-eight SGA and 48 AGA neonates of similar gestation (32.8 ± 2.1 vs. 32.5 ± 1.9) were enrolled. On the first postnatal day, the cerebral oxygenation was equal between SGA and AGA neonates (71 ± 7% vs. 72 ± 8%); however, in the subgroup analysis, males had higher oxygenation compared to female SGA neonates (73 ± 7% vs. 69 ± 7%, P = 0.04). Cerebral perfusion was significantly higher in SGA neonates on the first postnatal day (1.4 ± 0.6 vs. 1.1 ± 0.5, P = 0.04), but this difference was diminished on subsequent measurements. There were no significant differences between the SGA and AGA infants regarding the composite cognitive, communication and motor index scores. The length of mechanical ventilation and late-onset sepsis were significant risk factors affecting the cognitive and communication composite index scores, respectively. Conclusion Cerebral oxygenation was equal between SGA and AGA neonates, while cerebral perfusion was transiently increased in SGA neonates during the first postnatal day. There was no significant association of cerebral oxygenation and perfusion with neurodevelopmental outcomes.

Association of Adverse Hearing, Growth, and Discharge Age Outcomes With Postnatal Cytomegalovirus Infection in Infants With Very Low Birth Weight

IMPORTANCE

Studies suggest that postnatal cytomegalovirus (CMV) infection can lead to long-term morbidity in infants with very low birth weight (VLBW; <1500 g), including bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and neurodevelopmental impairment. However, to date, the association of postnatal CMV with hearing, growth, and length of stay among VLBW infants is unknown.

OBJECTIVES

To determine the risk for failed hearing screen, increased postnatal age at discharge, or decreased growth at discharge in VLBW infants with postnatal CMV infection compared with CMV-uninfected infants and to compare the risk for other major outcomes of prematurity, including BPD and NEC, in infants with and without postnatal CMV infection.

PARTICIPANTS

This multicenter retrospective cohort study included VLBW infants from 302 neonatal intensive care units managed by the Pediatrix Medical Group from January 1, 2002, through December 31, 2016. Infants hospitalized on postnatal day 21 with a diagnosis of postnatal CMV and hearing screen results after a postmenstrual age of 34 weeks were included in the study population. Data were analyzed from December 11, 2017, to June 14, 2019.

MAIN OUTCOMES AND MEASURES

Infants with and without postnatal CMV infection were matched using propensity scores. Poisson and linear regression were used to examine the association between postnatal CMV and the risk of failed hearing screen, postnatal age at discharge, growth, BPD, and NEC.

RESULTS

A total of 304 infants with postnatal CMV were identified, and 273 of these infants (89.8%; 155 boys [56.8%]) were matched with 273 infants without postnatal CMV (148 boys [54.2%]). Hearing screen failure occurred in 45 of 273 infants (16.5%) with postnatal CMV compared with 25 of 273 infants (9.2%) without postnatal CMV (risk ratio [RR], 1.80; 95% CI, 1.14 to 2.85; P = .01). Postnatal CMV was also associated with an increased postnatal age at discharge of 11.89 days (95% CI, 6.72 to 17.06 days; P < .001) and lower weight-for-age z score (-0.23; 95% CI, -0.39 to -0.07; P = .005). Analysis confirmed an increased risk of BPD (RR, 1.30; 95% CI, 1.17 to 1.44; P < .001), previously reported on infants from this cohort from 1997 to 2012, but not an increased risk of NEC after postnatal day 21 (RR, 2.00; 95% CI, 0.18 to 22.06; P = .57).

CONCLUSIONS AND RELEVANCE

These data suggest that postnatal CMV infection is associated with lasting sequelae in the hearing and growth status of VLBW infants and with prolonged hospitalization. Prospective studies are needed to determine the full effects of postnatal CMV infection and whether antiviral treatment reduces the associated morbidity.

Prophylactic Sildenafil in Preterm Infants at Risk of Bronchopulmonary Dysplasia: A Pilot Randomized, Double-Blinded, Placebo-Controlled Trial

BACKGROUND

Bronchopulmonary dysplasia (BPD) is the need for oxygen therapy at 36 weeks postmenstrual age (PMA). Sildenafil has been shown to enhance the lung alveolarization and vascularization in newborn animal models after lung injury and has possible therapeutic potential for the prevention of BPD.

OBJECTIVE

To perform a proof-of-concept, Phase II, pilot randomized, double-blind, clinical trial to study the efficacy of sildenafil in preventing BPD, in postnatal (< 24 h), extremely and very preterm infants.

METHODS

This Phase II, pilot randomized, double-blind, clinical trial was conducted in the Neonatal Intensive Care Unit of Women's Wellness and Research Center, Doha, Qatar during 2012-2014. Infants of 24^0/7-29^6/7 weeks' gestation were eligible if they needed respiratory or oxygen support ≥ 25% at randomization, and if they were at a postnatal age of < 24 h at randomization. Forty preterm infants were randomly assigned to receive off-label oral sildenafil (0.5 mg/kg every 6 h) or a placebo solution, for one week. The primary endpoints were the incidence of BPD and death at 36 weeks PMA, and the side effects. Secondary outcomes included the incidence of BPD and the respiratory support at day 28 of life, duration of oxygen use, fraction of inspired oxygen use at 36 weeks and 28 days of life, duration of hospitalization, and the incidence of significant retinopathy of prematurity, severe intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, patent ductus arteriosus, and late sepsis.

RESULTS

No significant differences were observed between the sildenafil and placebo study groups in mortality at 36 weeks PMA (10% vs 20%, p = 1), respiratory support at 36 weeks (30% vs 25%, p = 0.57), and side effects (0% vs 0%). For all other secondary outcomes, no significant differences were detected.

CONCLUSIONS

While not associated with side effects, off-label oral sildenafil did not demonstrate benefits in the prevention of BPD or death in the extreme and very preterm infants. Future studies of dosing and efficacy that target different regimens of sildenafil are warranted before sildenafil is recommended for the prevention of BPD.

The Inter-Relationships of Extremely Low Birth Weight, Asthma, and Behavior: A Study of Common Cause, Mediation, and Moderation

BACKGROUND

Extremely low birth weight (ELBW; <1000 g) infants are at risk for both asthma and problems like inattention, hyperactivity, anxiety, and depression. Asthma predicts behavioral and emotional problems in term-born children. The nature of these associations is poorly understood. We tested 3 models of association: independent risk, mediation, and effect modification to explore interplay among birth weight, asthma, and behavioral and emotional problems.

METHODS

We used data from a prospective cohort of ELBW infants born 1992 to 1995. Exposure was ELBW; primary outcomes were parent-reported diagnosis of asthma and symptoms of inattention, hyperactivity, anxiety, and depression at age 8 years. Covariates included child sex and maternal socioeconomic status.

RESULTS

There were 139 ELBW and 101 normal BW (>2500 g) children followed to 8 years. ELBW children were more likely to have asthma (35.7% vs 14.4%, P < .05). Inattention, hyperactivity, depression, and anxiety scores were higher among ELBW children and children with asthma. ELBW was a common cause of asthma and anxiety. There was no evidence of mediation or effect modification by asthma on the effect of ELBW on behavior and emotion symptoms.

CONCLUSION

Asthma does not underlie or amplify the effect of ELBW on behavioral and emotional problems at school age, suggesting that increased risk for respiratory morbidity and neurodevelopment represent largely independent consequences of developmental vulnerability related to ELBW. Noting the impact of chronic illnesses on neurodevelopment in other populations, data focused on symptom trajectories over time in a larger cohort may be necessary to shed further light onto this question.

Retinopathy of Prematurity and Bronchopulmonary Dysplasia are Independent Antecedents of Cortical Maturational Abnormalities in Very Preterm Infants

Very preterm (VPT) infants are at high-risk for neurodevelopmental impairments, however there are few validated biomarkers at term-equivalent age that accurately measure abnormal brain development and predict future impairments. Our objectives were to quantify and contrast cortical features between full-term and VPT infants at term and to associate two key antecedent risk factors, bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP), with cortical maturational changes in VPT infants. We prospectively enrolled a population-based cohort of 110 VPT infants (gestational age ≤31 weeks) and 51 healthy full-term infants (gestational age 38-42 weeks). Structural brain MRI was performed at term. 94 VPT infants and 46 full-term infants with high-quality T2-weighted MRI were analyzed. As compared to full-term infants, VPT infants exhibited significant global cortical maturational abnormalities, including reduced surface area (-5.9%) and gyrification (-6.7%) and increased curvature (5.9%). In multivariable regression controlled for important covariates, BPD was significantly negatively correlated with lobar and global cortical surface area and ROP was significantly negatively correlated with lobar and global sulcal depth in VPT infants. Our cohort of VPT infants exhibited widespread cortical maturation abnormalities by term-equivalent age that were in part anteceded by two of the most potent neonatal diseases, BPD and ROP.

Bronchopulmonary dysplasia

In the absence of effective interventions to prevent preterm births, improved survival of infants who are born at the biological limits of viability has relied on advances in perinatal care over the past 50 years. Except for extremely preterm infants with suboptimal perinatal care or major antenatal events that cause severe respiratory failure at birth, most extremely preterm infants now survive, but they often develop chronic lung dysfunction termed bronchopulmonary dysplasia (BPD; also known as chronic lung disease). Despite major efforts to minimize injurious but often life-saving postnatal interventions (such as oxygen, mechanical ventilation and corticosteroids), BPD remains the most frequent complication of extreme preterm birth. BPD is now recognized as the result of an aberrant reparative response to both antenatal injury and repetitive postnatal injury to the developing lungs. Consequently, lung development is markedly impaired, which leads to persistent airway and pulmonary vascular disease that can affect adult lung function. Greater insights into the pathobiology of BPD will provide a better understanding of disease mechanisms and lung repair and regeneration, which will enable the discovery of novel therapeutic targets. In parallel, clinical and translational studies that improve the classification of disease phenotypes and enable early identification of at-risk preterm infants should improve trial design and individualized care to enhance outcomes in preterm infants.