Postnatal steroid management in preterm infants with evolving bronchopulmonary dysplasia

Antibiotics and beyond: Unraveling the dynamics of bronchopulmonary dysplasia in very preterm infants

BACKGROUND

Bronchopulmonary dysplasia (BPD) remains a significant challenge in neonatal care. Prenatal inflammation and neonatal sepsis contribute to the multifactorial nature of BPD. A potential association between empirical antibiotic therapy and BPD risk has been proposed due to microbiota dysbiosis in very low birth weight premature infants.

METHODS

A single centered retrospective cohort study of preterm infants (24-32 weeks gestation) from 2014 to 2021. The study compared groups that received empirical antibiotics in the first days of life and those that did not receive any antibiotic in the first days of life. The primary outcomes studied were BPD, death, and the combined outcome of BPD/death. Statistical analysis employed t-tests, Mann-Whitney U, Chi-square, and logistic regression.

RESULTS

Of 454 preterm infants, 61.5% received antibiotics. This group had lower gestational age, birth weight, and Apgar scores. Antibiotic use was associated with higher incidence of BPD (35.5% vs. 10.3%), death (21.5% vs. 8.6%), and combined outcomes (54.5% vs. 18.3%). In multivariate analysis, antibiotic use independently associated with BPD (OR 2.58, p < 0.001) and combined outcome BPD/death (OR 2.06, p < 0.02). Antenatal corticosteroids provided protection against BPD, but not mortality.

CONCLUSION

This study suggests an association between early empirical antibiotic use and BPD in preterm infants, emphasizing the need for judicious antibiotic practices in neonatal care.

Oral DHA supplementation and retinopathy of prematurity: the Joinville DHA Clinical Trial

Retinopathy of prematurity (ROP) is a leading cause of blindness in premature infants. The condition is associated with DHA deficiency. This study aimed to investigate the effect of DHA supplementation on the occurrence of ROP in infants receiving oral oil drops. It is part of the Joinville DHA study, a non-parallel-group cohort study conducted from March 2020 to January 2023 at a public maternity hospital in Brazil. Infants born before 33 weeks of gestational age or with a birth weight ≤ 1500 g were recruited. Among 155 infants, 81 did not receive and 74 received DHA supplementation until complete vascularisation of the peripheral retina. There was a higher incidence of infants with ROP in the unsupplemented group (58·6 %) compared with the DHA group (41·4 %), but this difference was NS (P = 0·22). Unadjusted logistic regression analysis showed that patent ductus arteriosus and neonatal corticosteroids were significantly (P < 0·05) associated with ROP in both groups. In the DHA group, surfactant use was also associated with ROP (P = 0·003). After adjusting for important covariates, patent ductus arteriosus and neonatal corticosteroids continued to be significant for infants in the unsupplemented group (OR = 3·99; P = 0·022 and OR = 5·64; P = 0·019, respectively). In the DHA group, only surfactant use continued to be associated with ROP (OR = 4·84; P = 0·015). In summary, DHA supplementation was not associated with ROP. Further studies are necessary to better understand the relationship between DHA supplementation, ROP and associated comorbidities.

Predicting iatrogenic adrenal insufficiency in neonates exposed to prolonged steroid courses: do cortisol levels help?

OBJECTIVE

To determine whether random cortisol levels obtained in neonates to assess for secondary adrenal insufficiency (AI) after prolonged steroid exposure are predictive of central AI.

STUDY DESIGN

Data were collected on neonates born 2017-2022 who received ≥10 consecutive days of systemic steroids and had cortisol measured thereafter. Data were then collected on whether those neonates developed signs of AI or had a failed adrenocorticotropic hormone (ACTH) stimulation test.

RESULTS

Of the 71 cortisol levels (in 67 neonates) that were analyzed, there was no difference in cortisol levels between neonates who developed AI (median cortisol level of 6.5 mcg/dl) and those who did not (median of 9.2 mcg/dl), or between those who failed their ACTH stimulation test or passed it, using Wilcoxon ranked sum tests.

CONCLUSION

These findings demonstrate that cortisol levels may not be helpful in identifying AI in neonates exposed to prolonged steroids.

Factors affecting length of stay according to bronchopulmonary dysplasia severity: a nationwide cohort study in Korea

BACKGROUND

Longer hospitalizations for preterm infants with bronchopulmonary dysplasia (BPD) delay developmental outcomes, increase the risk for hospital-acquired complications, and exert a substantial socioeconomic burden. This study aimed to identify factors associated with an extended length of stay (LOS) at different levels of severity of BPD.

METHODS

A cohort study was conducted using the Korean Neonatal Network registry of very low birth weight infants with BPD between 2013 and 2017 through retrospective analysis.

RESULTS

A total of 4263 infants were diagnosed with BPD. For mild BPD, infants requiring surgical treatment for patent ductus arteriosus needed a longer LOS [eadjusted β coefficients (adj β) 1.041; 95% confidence interval (CI): 0.01-0.08] and hydrocephalus (eadj β 1.094; 95% CI 0.01-0.17). In moderate BPD, infants administered steroids or with intraventricular hemorrhage required a longer LOS (eadj β 1.041; 95% CI 0.00-0.07 and eadj β 1.271; 95% CI 0.11-0.38, respectively). In severe BPD, infants with comorbidities required a longer LOS: pulmonary hypertension (eadj β 1.174; 95% CI 0.09-0.23), administrated steroid for BPD (eadj β 1.116; 95% CI 0.07-0.14), sepsis (eadj β 1.062; 95% CI 0.01-0.11), patent ductus arteriosus requiring surgical ligation (eadj β 1.041; 95% CI 0.00-0.08), and intraventricular hemorrhage (eadj β 1.016; 95% CI 0.05-0.26). Additionally, the higher the clinical risk index score, the longer the LOS needed for infants in all groups.

CONCLUSIONS

The factors affecting LOS differed according to the severity of BPD. Individualized approaches to reducing LOS may be devised using knowledge of the various risk factors affecting LOS by BPD severity.

Inhaled Corticosteroid Exposure in Hospitalized Infants with Bronchopulmonary Dysplasia

OBJECTIVE

The objective of this paper was to determine inhaled corticosteroid (IC) use in infants with bronchopulmonary dysplasia (BPD), define the interhospital variation of IC administration to infants with BPD, and compare clinical, demographic, and hospital factors associated with IC use.

STUDY DESIGN

Using the Pediatric Health Information System database, a retrospective multicenter cohort of 4,551 infants born at <32 weeks of gestation with developing BPD was studied. The clinical, demographic, and hospital characteristics of infants exposed and not exposed to ICs were compared.

RESULTS

IC use varied markedly between hospitals, ranging from 0 to 66% of infants with BPD exposed to ICs. Increased annual BPD census was not associated with IC use. In total, 25% (1,144 out of 4,551) of patients with BPD and 43% (536 out of 1,244) of those with severe BPD received ICs. Increased IC exposure was associated with lower birth weight and gestational age, days on respiratory support, need for positive pressure ventilation at 36-week postmenstrual age, need for tracheostomy, and increased use of systemic steroids, bronchodilators, and diuretics.

CONCLUSION

IC exposure is common in infants with BPD, with substantial interhospital variability. IC use was associated with more severe disease. Hospital experience did not account for the wide variability in IC use by the hospital. Further research into the effects of ICs use is urgently needed to help guide their use in this vulnerable population.

KEY POINTS

· The risks and benefits of IC use in infants with BPD are incompletely understood.. · IC use is common in infants with BPD (25%) and severe BPD (43%) varies widely by hospital (0-66% of patients with BPD received an IC).. · Hospital experience did not account for the wide interhospital variation in IC use..

[Impact of different angles of pulmonary surfactant administration on bronchopulmonaryplasia and intracranial hemorrhage in preterm infants: a prospective randomized controlled study]

OBJECTIVES

To investigate the effects of different angles of pulmonary surfactant (PS) administration on the incidence of bronchopulmonary dysplasia and intracranial hemorrhage in preterm infants.

METHODS

A prospective study was conducted on 146 preterm infants (gestational age <32 weeks) admitted to the Department of Neonatology, Provincial Hospital Affiliated to Anhui Medical University from January 2019 to May 2023. The infants were randomly assigned to different angles for injection of pulmonary surfactant groups: 0° group (34 cases), 30° group (36 cases), 45° group (38 cases), and 60° group (38 cases). Clinical indicators and outcomes were compared among the groups.

RESULTS

The oxygenation index was lower in the 60° group compared with the other three groups, with shorter invasive ventilation time and oxygen use time, and a lower incidence of bronchopulmonary dysplasia than the other three groups (P<0.05). The incidence of intracranial hemorrhage was lower in the 60° group compared to the 0° group (P<0.05). The cure rate in the 60° group was higher than that in the 0° group and the 30° group (P<0.05).

CONCLUSIONS

The clinical efficacy of injection of pulmonary surfactant at a 60° angle is higher than other angles, reducing the incidence of intracranial hemorrhage and bronchopulmonary dysplasia in preterm infants.

Corticosteroids for the prevention and treatment of bronchopulmonary dysplasia: an overview of systematic reviews

BACKGROUND

Bronchopulmonary dysplasia (BPD) remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD, explaining the rationale for investigating postnatal corticosteroids. Multiple systematic reviews (SRs) have summarised the evidence from numerous randomised controlled trials (RCTs) investigating different aspects of administrating postnatal corticosteroids. Besides beneficial effects on the outcome of death or BPD, potential short- and long-term harms have been reported.

OBJECTIVES

The primary objective of this overview was to summarise and appraise the evidence from SRs regarding the efficacy and safety of postnatal corticosteroids in preterm infants at risk of developing BPD.

METHODS

We searched the Cochrane Database of Systematic Reviews, MEDLINE, Embase, CINAHL, and Epistemonikos for SRs in April 2023. We included all SRs assessing any form of postnatal corticosteroid administration in preterm populations with the objective of ameliorating pulmonary disease. All regimens and comparisons were included. Two review authors independently checked the eligibility of the SRs comparing corticosteroids with placebo, and corticosteroids with different routes of administration and regimens. The included outcomes, considered key drivers in the decision to administer postnatal corticosteroids, were the composite outcome of death or BPD at 36 weeks' postmenstrual age (PMA), its individual components, long-term neurodevelopmental sequelae, sepsis, and gastrointestinal tract perforation. We independently assessed the methodological quality of the included SRs by using AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews) and ROBIS (Risk Of Bias In Systematic reviews) tools. We assessed the certainty of the evidence using GRADE. We provided a narrative description of the characteristics, methodological quality, and results of the included SRs.

MAIN RESULTS

We included nine SRs (seven Cochrane, two non-Cochrane) containing 87 RCTs, 1 follow-up study, and 9419 preterm infants, investigating the effects of postnatal corticosteroids to prevent or treat BPD. The quality of the included SRs according to AMSTAR 2 varied from high to critically low. Risk of bias according to ROBIS was low. The certainty of the evidence according to GRADE ranged from very low to moderate. Early initiated systemic dexamethasone (< seven days after birth) likely has a beneficial effect on death or BPD at 36 weeks' PMA (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.81 to 0.95; number needed to treat for an additional beneficial outcome (NNTB) 16, 95% CI 10 to 41; I2 = 39%; 17 studies; 2791 infants; moderate-certainty evidence) and on BPD at 36 weeks' PMA (RR 0.72, 95% CI 0.63 to 0.82; NNTB 13, 95% CI 9 to 21; I2 = 39%; 17 studies; 2791 infants; moderate-certainty evidence). Early initiated systemic hydrocortisone may also have a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.90, 95% CI 0.82 to 0.99; NNTB 18, 95% CI 9 to 594; I2 = 43%; 9 studies; 1376 infants; low-certainty evidence). However, these benefits are likely accompanied by harmful effects like cerebral palsy or neurosensory disability (dexamethasone) or gastrointestinal perforation (both dexamethasone and hydrocortisone). Late initiated systemic dexamethasone (≥ seven days after birth) may have a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.75, 95% CI 0.67 to 0.84; NNTB 5, 95% CI 4 to 9; I2 = 61%; 12 studies; 553 infants; low-certainty evidence), mostly contributed to by a beneficial effect on BPD at 36 weeks' PMA (RR 0.76, 95% CI 0.66 to 0.87; NNTB 6, 95% CI 4 to 13; I2 = 14%; 12 studies; 553 infants; low-certainty evidence). No harmful side effects were shown in the outcomes chosen as key drivers to the decision to start or withhold late systemic dexamethasone. No effects, either beneficial or harmful, were found in the subgroup meta-analyses of late hydrocortisone studies. Early initiated inhaled corticosteroids probably have a beneficial effect on death and BPD at 36 weeks' PMA (RR 0.86, 95% CI 0.75 to 0.99; NNTB 19, 95% CI not applicable; I2 = 0%; 6 studies; 1285 infants; moderate-certainty evidence), with no apparent adverse effects shown in the SRs. In contrast, late initiated inhaled corticosteroids do not appear to have any benefits or harms. Endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier likely has a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.60, 95% CI 0.49 to 0.74; NNTB 4, 95% CI 3 to 6; I2 = 0%; 2 studies; 381 infants; moderate-certainty evidence) and on BPD at 36 weeks' PMA. No evidence of harmful effects was found. There was little evidence for effects of different starting doses or timing of systemic corticosteroids on death or BPD at 36 weeks' PMA, but potential adverse effects were observed for some comparisons. Lowering the dose might result in a more unfavourable balance of benefits and harms. Moderately early initiated systemic corticosteroids, compared with early systemic corticosteroids, may result in a higher incidence of BPD at 36 weeks' PMA. Pulse dosing instead of continuous dosing may have a negative effect on death and BPD at 36 weeks' PMA. We found no differences for the comparisons of inhaled versus systemic corticosteroids.

AUTHORS' CONCLUSIONS

This overview summarises the evidence of nine SRs investigating the effect of postnatal corticosteroids in preterm infants at risk for BPD. Late initiated (≥ seven days after birth) systemic administration of dexamethasone is considered an effective intervention to reduce the risk of BPD in infants with a high risk profile for BPD, based on a favourable balance between benefits and harms. Endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier is a promising intervention, based on the beneficial effect on desirable outcomes without (so far) negative side effects. Pending results of ongoing large, multicentre RCTs investigating both short- and long-term effects, endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier is not appropriate for clinical practice at present. Early initiated (< seven days after birth) systemic dexamethasone and hydrocortisone and late initiated (≥ seven days after birth) hydrocortisone are considered ineffective interventions, because of an unfavourable balance between benefits and harms. No conclusions are possible regarding early and late inhaled corticosteroids, as more research is needed.

Effects of postnatal corticosteroids on lung development in newborn animals. A systematic review

BACKGROUND

Postnatal systemic corticosteroids reduce the risk of bronchopulmonary dysplasia but the effect depends on timing, dosing, and type of corticosteroids. Animal studies may provide valuable information on these variable effects. This systematic review summarizes the effects of postnatal systemic corticosteroids on lung development in newborn animals.

METHODS

A systematic search was performed in PubMed and Embase in December 2022. The protocol was published on PROSPERO (CRD42021177701).

RESULTS

Of the 202 eligible studies, 51 were included. Only newborn rodent studies met the inclusion criteria. Most studies used dexamethasone (98%). There was huge heterogeneity in study outcome measures and corticosteroid treatment regimens. Reporting of study quality indicators was mediocre and risk of bias was unclear due to poor reporting of study methodology. Meta-analysis showed that postnatal corticosteroids caused a decrease in body weight as well as persistent alveolar simplification. Subgroup analyses revealed that healthy animals were most affected.

CONCLUSION

In newborn rodents, postnatal systemic corticosteroids have a persistent negative effect on body weight and lung development. There was huge heterogeneity in experimental models, mediocre study quality, unclear risk of bias, and very small subgroups for meta-analysis which limited firm conclusions.

IMPACT

Postnatal corticosteroids reduce the risk of bronchopulmonary dysplasia but the effect depends on timing, dosing, and type of corticosteroids while the underlying mechanism of this variable effect is unknown. This is the first systematic review and meta-analysis of preclinical newborn animal studies reviewing the effect of postnatal systemic corticosteroids on lung development. In newborn rodent models, postnatal corticosteroids have a persistent negative effect on body weight and lung alveolarization, especially in healthy animals.

Factors associated with the response to postnatal dexamethasone use in very low birthweight infants: a nationwide cohort study

BACKGROUND

Dexamethasone is widely used as a systemic corticosteroid to treat and prevent bronchopulmonary dysplasia (BPD) in preterm infants. We evaluated the current epidemiology of dexamethasone use to prevent BPD and analyse the factors associated with the response to dexamethasone in very low birthweight infants using a nationwide database.

METHODS

We included very low birthweight infants born between January 2013 and December 2020 with a gestational age of 23-31 weeks using data from the Korean Neonatal Network registry. Patients were grouped based on their dexamethasone use into 'Dex' or 'No Dex' groups. Clinical variables and data were collected, and the annual trends of dexamethasone use and the proportion of patients who received dexamethasone according to gestational age were analysed. Respiratory outcomes were compared between the groups. Univariate and multivariate analyses were performed to analyse factors associated with the response to dexamethasone in BPD.

RESULTS

Of 11 261 eligible infants, 2313 (20.5%) received dexamethasone, and 1714 (74.1%) of them were diagnosed with moderate-to-severe BPD. The 8-year annual prevalence of dexamethasone use was 17.7-22.3%. The 'Dex' group had more moderate-to-severe BPD, more frequent invasive ventilation use at a postmenstrual age of 36 weeks and longer ventilator duration. Birth weight, 5-minute APGAR score, pulmonary hypertension within the first 28 days, surgical treatment of patent ductus arteriosus, medical treatment of patent ductus arteriosus, pathological chorioamnionitis, hydrocortisone or budesonide use, surgical management of necrotising enterocolitis and fungal sepsis were associated with BPD after dexamethasone use.

CONCLUSIONS

Approximately 20.5% of preterm infants received dexamethasone, and the frequency increased as gestational age decreased. Poor response to dexamethasone was associated with antenatal and postnatal inflammation, low birth weight and early pulmonary hypertension.

Postnatal Corticosteroids To Prevent Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a common, severe chronic respiratory disease that affects very preterm infants. In utero and postnatal exposure to proinflammatory stimuli contribute to the pathophysiology of BPD. Corticosteroids, because of their potent anti-inflammatory properties, may decrease respiratory morbidity and reduce the risk of BPD in very preterm infants. However, these medications can have adverse effects on the developing brain and other organ systems. This review examines current evidence on the risks and benefits of postnatal corticosteroids used to prevent BPD in preterm infants.

Comparing low-dose (DART) and enhanced low-dose dexamethasone regimens in preterm infants with bronchopulmonary dysplasia

Introduction

Determining the optimal dexamethasone dosage for facilitating extubation in extremely low birth weight (ELBW) infants with bronchopulmonary dysplasia (BPD) remains uncertain. This study aims to compare the effectiveness of low-dose (DART) and enhanced low-dose dexamethasone regimens in achieving successful extubation in these infants.

Methods

We conducted a retrospective cohort study at the Women's Wellness and Research Center (WWRC) involving ELBW infants who received dexamethasone for BPD prevention or treatment, or for extubation between January 1st, 2015, and December 31st, 2019. Our goal was to assess successful extubation within various time points of treatement.

Results

A total of 77 patients, matched in gestational age and BW, were enrolled in the study, receiving a total of 121 dexamethasone courses. Low-dose dexamethasone courses were administered 75 times to 49 infants, while 46 courses of enhanced low-dose were given to 28 infants. Treatment commenced at 30.8 ± 3.4 weeks post-menstrual age, compared to 32.1 ± 2.5 weeks in the enhanced low-dose group (p = 0.014). The median (IQR) course duration was seven (3-10) days in the low-dose group, while it was 10 (8-14) days in the enhanced low-dose group (p < 0.001). The median (IQR) course dose was 0.73 (0.53-0.86) mg/kg in the low-dose group and 1.27 (0.97-2.05) mg/kg in the enhanced low-dose group (p < 0.001). There were no differences in extubation success at any time point between the two groups at 72 h and seven days after treatment initiation, by course completion, and within seven days after treatment completion. However, regression analysis identified several predictors of successful extubation; baseline FiO2, course duration, and duration of invasive mechanical ventilation were negatively associated with successful extubation at various time points, while received dose per kg and cumulative dose positively correlated with successful extubation at different time points. No significant differences were observed in secondary outcomes, including death or BPD.

Conclusion

The choice between low-dose and enhanced low-dose dexamethasone regimens may not significantly impact extubation success. However, careful consideration of dosing, ventilation status, and treatment duration remains crucial in achieving successful extubation. This study highlights the need for personalized dexamethasone therapy in ELBW infants.

Preterm lung and brain responses to mechanical ventilation and corticosteroids

Mechanical ventilation is necessary to maintain oxygenation and ventilation in many preterm infants. Unfortunately, even short periods of mechanical ventilation can cause lung and airway injury, and initiate the lung inflammation that contributes to the development of bronchopulmonary dysplasia (BPD). The mechanical stretch leads to airway cell differentiation and simplification of the alveoli, and releases cytokines that cause systemic response in other organs. Mechanical ventilation also leads to brain injury (IVH, white and gray matter) and neuronal inflammation that can affect the neurodevelopment of preterm infants. In efforts to decrease BPD, corticosteroids have been used for both prevention and treatment of lung inflammation. Corticosteroids have also been demonstrated to cause neuronal injury, so the clinician must balance the negative effects of both mechanical ventilation and steroids on the brain and lungs. Predictive models for BPD can help assess the infants who will benefit most from corticosteroid exposure. This review describes the lung and brain injury from mechanical ventilation in the delivery room and chronic mechanical ventilation in animal models. It provides updates on the current guidelines for use of postnatal corticosteroids (dexamethasone, hydrocortisone, budesonide, budesonide with surfactant) for the prevention and treatment of BPD, and the effects the timing of each steroid regimen has on neurodevelopment.

Pharmacotherapy of BPD: Current status & future perspectives

Bronchopulmonary dysplasia (BPD) is a disease exclusive to prematurity and has changed in its definition since Northway first described it in 1967. There have been countless clinical trials evaluating the efficacy of drugs in the treatment and prevention of BPD in human subjects, and an even larger number of animal studies. Despite these, only a handful of drugs are used at the bedside today, primarily due to the lack of consistent efficacy seen in clinical trials or due to reports of adverse effects. This review summarizes the list of the most commonly used drugs and emerging new therapies which target BPD and BPD-related pulmonary hypertension (BPD-PH), including those which have shown promise in human trials but are not yet used routinely.

Outpatient management of established bronchopulmonary dysplasia: An update

As the incidence of infants with bronchopulmonary dyspasia (BPD) has continued to rise, so has their rate of survival. Their medical management is often complex and requires the use of numerous therapies such as steroids, bronchodilators, diuretics and modalities to deliver supplemental oxygen and positive pressure. It also requires multi-disciplinary care to ensure adequate growth and to optimize neurodevelopmental outcomes. This review aims to discuss the most widely used therapies in the treatment of patients with established BPD. The focus will be on ongoing outpatient (post-neonatal intensive care) management of children with BPD. Since many of the mentioned therapies lack solid evidence to support their use, more high quality research, such as randomized controlled trials, is needed to assess their effectiveness using defined outcomes.

Effects of Milrinone on Neonates after Patent Ductus Arteriosus Ligation: A Retrospective Nationwide Database Study

INTRODUCTION

Milrinone is administered after patent ductus arteriosus (PDA) ligation to prevent and treat postoperative hemodynamic instability (i.e., postligation cardiac syndrome). We aimed to explore the effectiveness of milrinone on in-hospital outcomes in infants who underwent PDA ligation using a nationwide inpatient database in Japan.

METHODS

Using the Japanese Diagnosis Procedure Combination database, we identified patients who received milrinone after PDA ligation (n = 428) in neonatal intensive care units between July 2010 and March 2021 and those who did not (n = 3,392). We conducted a 1:4 propensity score-matched analysis with adjustment for background characteristics (e.g., gestational age, birth weight, comorbidities, preoperative treatments, and hospital background) to compare morbidities (bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and retinopathy of prematurity), mortality, total hospitalization costs, and other outcomes. For sensitivity analysis, we performed an overlap propensity score-weighted analysis.

RESULTS

In-hospital morbidity, bronchopulmonary dysplasia, intraventricular hemorrhage, and necrotizing enterocolitis occurred in 58%, 48%, 9.5%, and 7.1% of patients, respectively; the in-hospital mortality was 5.4%. After 1:4 propensity score matching, no significant difference was observed regarding mortality (7.1 vs. 5.7%), in-hospital morbidity (55 vs. 50%), bronchopulmonary dysplasia (44 vs. 41%), intraventricular hemorrhage (7.8 vs. 9.1%), necrotizing enterocolitis (8.5 vs. 8.9%), retinopathy of prematurity (21 vs. 22%), or total hospitalization costs (median: approximately 86,000 vs. 82,000 US dollars) between milrinone users (n = 425) and nonusers (n = 1,698). Sensitivity analyses yielded consistent results.

CONCLUSIONS

Milrinone use after PDA ligation was not associated with improved in-hospital outcomes, such as mortality and morbidity.

Case report: A case of spinal muscular atrophy in a preterm infant: risks and benefits of treatment

Spinal muscular atrophy (SMA) is a neuromuscular genetic disorder caused by the loss of lower motor neurons leading to progressive muscle weakness and atrophy. With the rise of novel therapies and early diagnosis on newborn screening (NBS), the natural history of SMA has been evolving. Earlier therapeutic interventions can modify disease outcomes and improve survival. The role of treatment in infants born preterm is an important question given the importance of early intervention. In this study, we discuss the case of an infant born at 32 weeks who was diagnosed with SMA on NBS and was treated with Spinraza® (Nusinersen) and Zolgensma® (Onasemnogene abeparvovec-xioi) within the first 2 months of life. With the scarce evidence that currently exists, clinicians should be aware of the efficacy and safety impact of early therapy particularly in the preterm infant.

Cryptotanshinone affects HFL-1 cells proliferation by inhibiting cytokines secretion in RAW264.7 cells and ameliorates inflammation and fibrosis in newborn rats with hyperoxia induced lung injury

Objective: Bronchopulmonary dysplasia (BPD) is a common complication of prematurity and has no specific treatment option. Moreover, inflammation and fibrosis play a vital role in the development of BPD. Thus, this study aimed to explore the role of the anti-inflammatory and anti-fibrotic drug cryptotanshinone (CTS) in the treatment of inflammation and fibrosis in BPD. Methods: In vivo, Sprague-Dawley rats (male) were divided into air, hyperoxia and CTS groups with different dose interventions (7.5, 15, and 30 mg/kg). A BPD rat model was induced by continuous inhalation of hyperoxia (95%) for 7 days, during which different doses of CTS were injected intraperitoneally. Furthermore, histological examination, hydroxyproline content measurement, Western blot and real-time quantitative polymerase chain reaction were used to detect the levels of inflammation and fibrosis in the tissues. RAW264.7 cells exposed to 95% oxygen were collected and co-cultured with fibroblasts to determine the expression levels of α-SMA, collagen-Ⅰ and MMPs. The levels of pro-inflammatory cytokines such as TNF-α, IL-6 and pro-fibrotic factor TGF-β1 in the supernatants were measured using enzyme-linked immunosorbent assay. Results: Haematoxylin and eosin staining revealed that CTS reduced the inflammatory response in rat lungs. Masson staining revealed that CTS alleviated the level of pulmonary fibrosis. CTS also reduced the levels of TNF-α, IL-6 and TGF-β1 along with the expression of the fibrosis marker α-SMA in lung tissue. Similarly, in vitro analysis revealed that CTS decreased the levels of TNF-α, IL-6 and TGF-β1 expressed in RAW 264.7 cells, and reduced α-SMA, collagen-Ⅰ, MMPs concentrations in HFL-1 cells co-cultured with the supernatant of RAW264.7 cells after hyperoxia. Conclusion: CTS can attenuate the hyperoxia-induced inflammatory response and the level of fibrosis by regulating the levels of inflammatory factors and fibrotic factor TGF-β1 expressed by macrophages, thereby highlighting the therapeutic potential of CTS in the treatment of BPD.

METTL3 promotes hyperoxia-induced pyroptosis in neonatal bronchopulmonary dysplasia by inhibiting ATG8-mediated autophagy

OBJECTIVES

N6-Methyladenosine (m6A) modification plays a vital role in lung disorders. However, the potential of m6A in neonatal Bronchopulmonary Dysplasia (BPD) has not been reported. This study aimed to investigate the roles of METTL3 in BPD.

METHODS

BPD models were established by hyperoxia in vivo and in vitro. Histological analysis was determined using HE staining. Gene expression was determined using Western blotting, qRT-PCR, and immunofluorescence. The release of IL-1β and IL-18 was detected using ELISA. The m6A sites of ATG8 were predicted by SCRAPM and verified by MeRIP assay. The location of GSDMD and ATG8 was determined by FISH assay. The interaction between ATG8 and GSDMD was detected using Coimmunoprecipitation (Co-IP). Cell pyroptosis was determined using flow cytometry and TUNEL assays.

RESULTS

METTL3 was overexpressed in BPD, which was accompanied by an increase in m6A levels. Interestingly, METTL3 suppressed hyperoxia-mediated damage and pyroptosis in BEAS-2B cells and promoted cell autophagy. METTL3-mediated m6A modification of ATG8 suppressed its expression and disrupted the interaction between ATG8 and GSDMD. However, autophagy inhibition induced pyroptosis in BEAS-2B cells. In vivo assays showed that METTL3-mediated autophagy inhibition induced a decrease in the radial alveolar count and an increase in the mean linear intercept and promoted cell pyroptosis.

CONCLUSION

In conclusion, METTL3-mediated cell pyroptosis promotes BPD by regulating the m6A modification of ATG8. This may provide new insight into the development of BPD.

Multidisciplinary bronchopulmonary dysplasia care

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is a chronic respiratory disease in neonates and infants, which often presents with multisystem organ involvement, co-morbidities, and prolonged hospital stays. Therefore, a multidisciplinary chronic care approach is needed in the severest forms of BPD to optimize outcomes. However, this approach can be challenging to implement. The objective of this article is to review and synthesize the available literature regarding multidisciplinary care in infants and children with established BPD, and to provide a framework that can guide clinical practice and future research.

AREAS COVERED

A literature search was conducted using Ovid MEDLINE, CINAHL, and Embase and several components of multidisciplinary management of BPD were identified and reviewed, including chronic care, team development, team members, discharge planning, and outpatient care.

EXPERT OPINION

Establishing a core multidisciplinary group familiar with the chronicity of established BPD is recommended as best practice for this population. Acknowledging this is not feasible for all individual centers, it is important for clinical practice and future research to focus on the development and incorporation of national consulting services, telemedicine, and educational resources.

Role of Postnatal Corticosteroids in the Treatment or Prevention of Bronchopulmonary Dysplasia

As the frequency of viable low birth weight preterm babies increases, bronchopulmonary dysplasia (BPD), one of the most important morbidities in these babies, also increases. Using postnatal steroids to reduce the development of BPD has not been fully enlightened. Besides all prevention strategies for reducing the development of BPD, it is known that steroid therapy used in the 1st week of life could induce negative neuromotor development according to current data. It may be recommended to administer low-dose dexamethasone between 8 and 49 days in infants dependent on mechanical ventilators in the postnatal period. It is seen that the use of hydrocortisone in the early period does not cause negative neuromotor development, but it cannot prevent the development of BPD as much as dexamethasone. All intensive care units must have their steroid protocol for BPD and use steroids in cases when the BPD development scale score is >60-65% and should have a goal of trying to keep the cumulative dose at the lowest level.

Systemic postnatal corticosteroid use for the prevention of bronchopulmonary dysplasia and its relationship to early neurodevelopment in extremely preterm infants

BACKGROUND

Systemic postnatal corticosteroid use in extremely preterm infants poses a risk of adverse neurodevelopmental outcomes. This study explores their use beyond seven days of age with early neurodevelopmental assessments during the fidgety period (9-20 weeks postterm age).

METHODS

This retrospective single-center cohort study included inborn extremely preterm infants from 1 January 2014 to 31 December 2018. Outborn infants, those with congenital or genetic abnormalities, and those who received postnatal corticosteroids for nonrespiratory reasons were excluded. The cohort was dichotomized based on the status of corticosteroid receipt. Early neurodevelopmental outcomes were reported using Prechtl's General Movements Assessment.

RESULTS

Of the 282 infants, 67 (23.75%) received corticosteroids. Of these, 34 (50.75%) received them for dependency on invasive ventilation (intermittent positive-pressure ventilation), and the remainder received them for dependency on non-invasive ventilation continuous positive airway pressure (CPAP) or bi-level positive airway pressure (BiPAP). Abnormal or absent fidgety movements were observed in 13% of infants (7/54) who received corticosteroids compared to 2% of infants (3/146) who did not. An increased odds for an abnormal general movements assessment from corticosteroid use after adjusting for gestational age [adjusted odds ratio (aOR) = 5.5, 95% confidence interval (CI) = 1.14-26.56] was observed. The motor optimality scores differed between the two groups [corticosteroid group: 25.5 (23-26) versus no-corticosteroid group: 26 (24-28); z =  - 2.02]. A motor optimality score < 20 was observed in 14.8% of infants (8/54) in the corticosteroid group compared to 2% of infants (3/146) in the noncorticosteroid group. This difference was significant after adjustment for gestational age (aOR 5.96, 95% CI 1.28-27.74).

CONCLUSIONS

Abnormal early neurodevelopment was observed in infants who received systemic postnatal corticosteroids. The relationship between these findings and other factors influencing early neurodevelopment needs further exploration.

Respiratory management in the premature neonate

INTRODUCTION

Advances in neonatal care have made possible the increased survival of extremely preterm infants. Even though there is widespread recognition of the harmful effects of mechanical ventilation on the developing lung, its use has become imperative in the management of micro-/nano-preemies. There is an increased emphasis on the use of less-invasive approaches such as minimally invasive surfactant therapy and non-invasive ventilation that have been proven to result in improved outcomes.

AREAS COVERED

Here, we review the evidence-based practices surrounding the respiratory management of extremely preterm infants including delivery room interventions, invasive and non-invasive ventilation approaches, and specific ventilator strategies in respiratory distress syndrome and bronchopulmonary dysplasia. Adjuvant relevant respiratory pharmacotherapies used in preterm neonates are also discussed.

EXPERT OPINION

Early use of non-invasive ventilation and use of less invasive surfactant administration are key strategies in the management of respiratory distress syndrome in preterm infants. Ventilator management in bronchopulmonary dysplasia must be tailored according to the individual phenotype. There is strong evidence to start caffeine early to improve respiratory outcomes, but evidence is lacking on the use of other pharmacological agents in preterm neonates, and an individualized approach has to be considered for their use.

Outcomes of and factors associated with the development of bronchopulmonary dysplasia with pulmonary hypertension in very low birth weight infants: A retrospective study in a medical center

Introduction

Bronchopulmonary dysplasia (BPD) with pulmonary hypertension (PH) leads to increased morbidity and mortality in extremely preterm infants. Recent studies have analyzed factors associated with development of PH in BPD; however, this research remains inconclusive, and controversy exists regarding the correlation between BPD and PH. This study aimed to investigate potential associated factors, clinical characteristics, and outcomes of BPD with pulmonary hypertension in very low birth weight (VLBW) preterm infants.

Methods

We conducted a retrospective study, reviewing the records of infants with gestational age (GA) <32 weeks and birth weight <1,500 g admitted to a tertiary neonatal intensive care unit between January 2020 and October 2021 who were diagnosed with moderate to severe BPD. Echocardiogram was performed at the postmenstrual age of 36 weeks or before discharge. The diagnosis of PH was based on the findings of echocardiogram. Prenatal and postnatal characteristics, demographic data, treatment details, and outcomes were collected and analyzed.

Results

A total of 139 VLBW infants with BPD were enrolled and divided into a PH group (n = 25) and a non-PH group (n = 114). The mean GA was 27.3 ± 2.3 weeks and the mean birth weight of infants with BPD was 927.3 ± 293.3 g. A multivariate logistic regression model revealed that a high positive end-expiratory pressure (PEEP) setting (OR: 2.105; 95% CI: 1.472-3.011; p < 0.001) in established BPD and surgical closure of patent ductus arteriosus (PDA; OR: 6.273; 95% CI: 1.574-24.977; p = 0.009) were associated with BPD-PH. Neonates with BPD who developed pulmonary hypertension remained hospitalized for longer (p < 0.001), received invasive mechanical ventilation support for longer (p < 0.001), had a higher incidence of retinopathy of prematurity (ROP; OR: 4.201; 95% CI: 1.561-11.304; p = 0.003), were more likely to require oxygen support at discharge (OR: 5.600; 95% CI: 2.175-14.416; p < 0.001), and were more likely to undergo tracheostomy (OR: 35.368; 95% CI: 4.03-310.43; p < 0.001).

Conclusion

PDA ligation and a higher PEEP setting were associated with BPD-PH in our cohort study. Compared with VLBW infants with BPD but without PH, infants with BPD and PH were hospitalized for longer, and also had a higher incidence of oxygen support after discharge, ROP, and tracheostomy.

The possible role of artificial intelligence in deciding postnatal steroid management in extremely premature ventilated infants

Clinical decision support (CDS) has shown a positive effect on physicians. There is variability among physicians about using postnatal steroids (PNS) in preterm (PT) infants. It is, therefore, essential to develop tools supporting the decision to use PNS in PT infants. We propose a model using online tools such as CDS in deciding to use PNS in PT infants. We combined the online bronchopulmonary dysplasia (BPD) estimator and extubation success calculator tools to be used as a simple bedside tool assisting decisions about using PNS in ventilated PT infants.

Circular RNAs expression profiles and bioinformatics analysis in bronchopulmonary dysplasia

BACKGROUND

Bronchopulmonary dysplasia (BPD) has long been considered the most challenging chronic lung disease for neonatologists and researchers due to its complex pathological mechanisms and difficulty in prediction. Growing evidence indicates that BPD is associated with the dysregulation of circular RNAs (circRNAs). Therefore, we aimed to explore the expression profiles of circRNAs and investigate the underlying molecular network associated with BPD.

METHODS

Peripheral blood was collected from very-low-birth-weight (VLBW) infants at 5-8 days of life to extract PBMCs. Microarray analysis and qRT-PCR tests were performed to determine the differentially expressed circRNAs (DEcircRNAs) between BPD and non-BPD VLBW infants. Simultaneous analysis of GSE32472 was conducted to obtain differentially expressed mRNAs (DEmRNA) from BPD infants. The miRNAs were predicted by DEcircRNAs and DEmRNAs of upregulated, respectively, and then screened for overlapping ones. GO and KEGG analysis was performed following construction of the competing endogenous RNA regulatory network (ceRNA) for further investigation.

RESULTS

A total of 65 circRNAs (52 upregulated and 13 downregulated) were identified as DEcircRNAs between the two groups (FC >2.0 and p.adj <0.05). As a result, the ceRNA network was constructed based on three upregulated DEcircRNAs validated by qRT-PCR (hsa_circ_0007054, hsa_circ_0057950, and hsa_circ_0120151). Bioinformatics analysis indicated these DEcircRNAs participated in response to stimulus, IL-1 receptor activation, neutrophil activation, and metabolic pathways.

CONCLUSIONS

In VLBW infants with a high risk for developing BPD, the circRNA expression profiles in PBMCs were significantly altered in the early post-birth period, suggesting immune dysregulation caused by infection and inflammatory response already existed.

Safety and Efficacy of Mesenchymal Stem Cells for the Treatment of Evolving and Established Bronchopulmonary Dysplasia: A Systematic Literature Review

Bronchopulmonary dysplasia (BPD) is a frequent sequela of modern medicine when infants are born prematurely. Currently, there is no single treatment or combination of treatments to prevent or fully treat BPD. Mesenchymal stem cells (MSCs) have promising properties that could aid in the reversal of lung injury, as seen in patients with BPD. This study reviews the available evidence regarding the safety and efficacy of the use of MSCs for the treatment of evolving and established BPD. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We found eight studies that fulfilled the inclusion and exclusion criteria. While all studies proved the safety and efficacy of MSCs administered intravenously and intratracheally, the only available randomized controlled trial (RCT) failed to demonstrate the benefit of MSC administration in the early treatment of BPD. The remaining studies varied between phase I clinical trials and case reports, but all seemed to show some evidence that MSCs may be of benefit in the late treatment of established BPD. Considering some of the studies have less evidence, early treatment to prevent lung fibrosis may be more successful, particularly in the younger gestational ages where lung development is more immature, and research should focus on this.

Landscape analysis for a neonatal disease progression model of bronchopulmonary dysplasia: Leveraging clinical trial experience and real-world data

The 21^st Century Cures Act requires FDA to expand its use of real-world evidence (RWE) to support approval of previously approved drugs for new disease indications and post-marketing study requirements. To address this need in neonates, the FDA and the Critical Path Institute (C-Path) established the International Neonatal Consortium (INC) to advance regulatory science and expedite neonatal drug development. FDA recently provided funding for INC to generate RWE to support regulatory decision making in neonatal drug development. One study is focused on developing a validated definition of bronchopulmonary dysplasia (BPD) in neonates. BPD is difficult to diagnose with diverse disease trajectories and few viable treatment options. Despite intense research efforts, limited understanding of the underlying disease pathobiology and disease projection continues in the context of a computable phenotype. It will be important to determine if: 1) a large, multisource aggregation of real-world data (RWD) will allow identification of validated risk factors and surrogate endpoints for BPD, and 2) the inclusion of these simulations will identify risk factors and surrogate endpoints for studies to prevent or treat BPD and its related long-term complications. The overall goal is to develop qualified, fit-for-purpose disease progression models which facilitate credible trial simulations while quantitatively capturing mechanistic relationships relevant for disease progression and the development of future treatments. The extent to which neonatal RWD can inform these models is unknown and its appropriateness cannot be guaranteed. A component of this approach is the critical evaluation of the various RWD sources for context-of use (COU)-driven models. The present manuscript defines a landscape of the data including targeted literature searches and solicitation of neonatal RWD sources from international stakeholders; analysis plans to develop a family of models of BPD in neonates, leveraging previous clinical trial experience and real-world patient data is also described.

Developing a machine learning-based tool to extend the usability of the NICHD BPD Outcome Estimator to the Asian population

The NICHD BPD Outcome Estimator uses clinical and demographic data to stratify respiratory outcomes of extremely preterm infants by risk. However, the Estimator does not have an option in its pull-down menu for infants of Asian descent. We hypothesize that respiratory outcomes in extreme prematurity among various racial/ethnic groups are interconnected and therefore the Estimator can still be used to predict outcomes in infants of Asian descent. Our goal was to apply a machine learning approach to assess whether outcome prediction for infants of Asian descent is possible with information hidden in the prediction results using White, Black, and Hispanic racial/ethnic groups as surrogates. We used the three racial/ethnic options in the Estimator to obtain the probabilities of BPD outcomes for each severity category. We then combined the probability results and developed three respiratory outcome prediction models at various postmenstrual age (PMA) by a random forest algorithm. We showed satisfactory model performance, with receiver operating characteristics area under the curve of 0.934, 0.850, and 0.757 for respiratory outcomes at PMA 36, 37, and 40 weeks, respectively, in the testing data set. This study suggested an interrelationship among racial/ethnic groups for respiratory outcomes among extremely preterm infants and showed the feasibility of extending the use of the Estimator to the Asian population.

Relative Adrenal Insufficiency in the Preterm Infant

Identifying relative adrenal insufficiency in the critically ill preterm neonate is not always clear-cut. Preterm infants with vasopressor-resistant shock may have persistent cardiovascular insufficiency, which can result in rapid decompensation. After attempts of resuscitation with fluids and inotropes, these infants are often found to respond to glucocorticoids. This raises the important question of how prevalent adrenal insufficiency is in the preterm population. This article reviews the development and role of the adrenal glands, defines relative adrenal insufficiency in the preterm population, discusses barriers to determining this diagnosis, and describes treatment options.

Pharmacotherapy in Bronchopulmonary Dysplasia: What Is the Evidence?

Bronchopulmonary Dysplasia (BPD) is a multifactorial disease affecting over 35% of extremely preterm infants born each year. Despite the advances made in understanding the pathogenesis of this disease over the last five decades, BPD remains one of the major causes of morbidity and mortality in this population, and the incidence of the disease increases with decreasing gestational age. As inflammation is one of the key drivers in the pathogenesis, it has been targeted by majority of pharmacological and non-pharmacological methods to prevent BPD. Most extremely premature infants receive a myriad of medications during their stay in the neonatal intensive care unit in an effort to prevent or manage BPD, with corticosteroids, caffeine, and diuretics being the most commonly used medications. However, there is no consensus regarding their use and benefits in this population. This review summarizes the available literature regarding these medications and aims to provide neonatologists and neonatal providers with evidence-based recommendations.

Dexamethasone Alters Tracheal Aspirate T-Cell Cytokine Production in Ventilated Preterm Infants

Postnatal corticosteroids improve respiratory status and facilitate respiratory support weaning in preterm infants with bronchopulmonary dysplasia (BPD). Older literature describes characteristic cytokine profiles in tracheal aspirates (TA) of BPD patients which are altered with corticosteroids. Corticosteroids also influence peripheral blood T-cell presence. However, little is known regarding TA T-cell phenotype and cytokine production before or after exogenous corticosteroids. We hypothesized that postnatal dexamethasone alters the TA T-cell cytokine profiles of preterm infants. TA samples were collected from 14 infants born from 23 0/7 to 28 6/7 weeks who were mechanically ventilated for at least 14 days. Samples were collected up to 72 h before a ten-day dexamethasone course and again 1 to 3 calendar days after dexamethasone initiation. The primary outcome was change in T cell populations present in TA and their intracellular cytokine profile after dexamethasone treatment, ascertained via flow cytometry. Following dexamethasone treatment, there were significant decreases in respiratory severity score (RSS), percent CD4+IL-6+ cells, CD8+IL-6+ cells, CXCR3+IL-6+ cells, and CXCR3+IL-2+ cells and total intracellular IFN-γ in TA. RSS significantly correlated with TA percent CD4+IL-6+ cells. To our knowledge, this is the first study demonstrating that dexamethasone reduced T-cell IL-6 and this reduction was associated with improved RSS in pre-term infants with evolving BPD.