Evaluating the use of corticosteroids in preventing and treating bronchopulmonary dysplasia in preterm neonates

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.

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.

Risk prediction of bronchopulmonary dysplasia in preterm infants by the nomogram model

Backgrounds and Aims

Bronchopulmonary dysplasia (BPD) has serious immediate and long-term sequelae as well as morbidity and mortality. The objective of this study is to develop a predictive model of BPD for premature infants using clinical maternal and neonatal parameters.

Methods

This single-center retrospective study enrolled 237 cases of premature infants with gestational age less than 32 weeks. The research collected demographic, clinical and laboratory parameters. Univariate logistic regression analysis was carried out to screen the potential risk factors of BPD. Multivariate and LASSO logistic regression analysis was performed to further select variables for the establishment of nomogram models. The discrimination of the model was assessed by C-index. The Hosmer-Lemeshow test was used to assess the calibration of the model.

Results

Multivariate analysis identified maternal age, delivery option, neonatal weight and age, invasive ventilation, and hemoglobin as risk predictors. LASSO analysis selected delivery option, neonatal weight and age, invasive ventilation, hemoglobin and albumin as the risk predictors. Both multivariate (AUC = 0.9051; HL P = 0.6920; C-index = 0.910) and LASSO (AUC = 0.8935; HL P = 0.7796; C-index = 0.899) - based nomograms exhibited ideal discrimination and calibration as confirmed by validation dataset.

Conclusions

The probability of BPD in a premature infant could be effectively predicted by the nomogram model based on the clinical maternal and neonatal parameters. However, the model required external validation using larger samples from multiple medical centers.

How to tame your genes: mechanisms of inflammatory gene repression by glucocorticoids

Glucocorticoids (GCs) are widely used therapeutic agents to treat a broad range of inflammatory conditions. Their functional effects are elicited by binding to the glucocorticoid receptor (GR), which regulates transcription of distinct gene networks in response to ligand. However, the mechanisms governing various aspects of undesired side effects versus beneficial immunomodulation upon GR activation remain complex and incompletely understood. In this review, we discuss emerging models of inflammatory gene regulation by GR, highlighting GR's regulatory specificity conferred by context-dependent changes in chromatin architecture and transcription factor or co-regulator dynamics. GR controls both gene activation and repression, with the repression mechanism being central to favorable clinical outcomes. We describe current knowledge about 3D genome organization and its role in spatiotemporal transcriptional control by GR. Looking beyond, we summarize the evidence for dynamics in gene regulation by GR through cooperative convergence of epigenetic modifications, transcription factor crosstalk, molecular condensate formation and chromatin looping. Further characterizing these genomic events will reframe our understanding of mechanisms of transcriptional repression by GR.

Let's Talk about Dex: When do the Benefits of Dexamethasone for Prevention of Bronchopulmonary Dysplasia Outweigh the Risks?

Bronchopulmonary dysplasia (BPD) is the most common complication of extreme prematurity and carries increased respiratory morbidity into childhood and adulthood. Systemic administration of dexamethasone during the preterm period has been shown to decrease the incidence of BPD in this population. However, enthusiasm about its use has been tempered by early evidence that suggested potential adverse neurodevelopmental outcomes. More recent studies suggest that the timing, dosing, and duration of therapy may have a significant impact on the safety and efficacy of dexamethasone administration and that side effects and harms may be minimized if its use is appropriately targeted. Focusing on studies published since the 2010s American Academy of Pediatrics (AAP) statement on dexamethasone, this review seeks to examine the evidence from recent clinical trials to present the current state of knowledge regarding the systemic dexamethasone administration to prevent BPD in extremely premature infants and how dose, duration, and timing might impact its safety and efficacy in this vulnerable population.

Influence of innate immune activation on endocrine and metabolic pathways in infancy

Prematurity is the leading cause of neonatal morbidity and mortality worldwide. Premature infants often require extended hospital stays, with increased risk of developing infection compared with term infants. A picture is emerging of wide-ranging deleterious consequences resulting from innate immune system activation in the newborn infant. Those who survive infection have been exposed to a stimulus that can impose long-lasting alterations into later life. In this review, we discuss sepsis-driven alterations in integrated neuroendocrine and metabolic pathways and highlight current knowledge gaps in respect of neonatal sepsis. We review established biomarkers for sepsis and extend the discussion to examine emerging findings from human and animal models of neonatal sepsis that propose novel biomarkers for early identification of sepsis. Future research in this area is required to establish a greater understanding of the distinct neonatal signature of early and late-stage infection, to improve diagnosis, curtail inappropriate antibiotic use, and promote precision medicine through a biomarker-guided empirical and adjunctive treatment approach for neonatal sepsis. There is an unmet clinical need to decrease sepsis-induced morbidity in neonates, to limit and prevent adverse consequences in later life and decrease mortality.

Modern pulmonary imaging of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a complex and serious cardiopulmonary morbidity in infants who are born preterm. Despite advances in clinical care, BPD remains a significant source of morbidity and mortality, due in large part to the increased survival of extremely preterm infants. There are few strong early prognostic indicators of BPD or its later outcomes, and evidence for the usage and timing of various interventions is minimal. As a result, clinical management is often imprecise. In this review, we highlight cutting-edge methods and findings from recent pulmonary imaging research that have high translational value. Further, we discuss the potential role that various radiological modalities may play in early risk stratification for development of BPD and in guiding treatment strategies of BPD when employed in varying severities and time-points throughout the neonatal disease course.

Description of a Nutrition Screening and Assessment Tool and Associations with Clinical Outcomes in Preterm Newborns

BACKGROUND

Preterm newborns have higher nutrition risk and mortality. Nutrition risk screening enables early intervention. This article evaluates a nutrition screening tool in a neonatal intensive care unit (NICU).

METHOD

Retrospective longitudinal study of preterm newborns (aged <37 weeks) in a NICU in Brazil from May 2018 to January 2019. Weight, length, and head circumference (HC) were analyzed. Nutrition screening was defined by care levels (CLs). Outcomes analyzed were bronchopulmonary dysplasia (BPD), peri-intraventricular hemorrhage (PIVH), retinopathy of prematurity (ROP), late sepsis, length of stay, mortality, and time receiving enteral and parenteral nutrition.

RESULTS

Data on 110 newborns were studied, with median gestational age 34 (31-35) weeks, mean weight 1914.92 g (±657.7), length 42.2 cm (±4.45), and HC 29.9 cm (±2.97). Most (82.7%) of them were adequate for gestational age. Screening classifications were 41.8% (n = 46) at CL 2, 41.8% (n = 46) at CL 3, and 16.4% (n = 18) at CL 4. CL 3 and CL 4 patients had higher frequencies of BPD (P = .003), ROP (P = .027), and PIVH (P = .006) and longer enteral time (P < .001) and length of stay (P < .001). All mortality occurred in CL 4 patients (P < .001).

CONCLUSIONS

CL 3 and CL 4 patients had more BPD, ROP, PIVH, and mortality and longer enteral nutrition. Hospital stay was longer for CL ≥3 than CL 2 patients. Patients classified as CL 3 and CL 4 by the nutrition screening tool may have higher nutrition risk.

Prenatal genetic diagnosis: Fetal therapy as a possible solution to a positive test

BACKGROUND

Fetal abnormalities cause 20% of perinatal deaths. Advances in prenatal genetic and other types of screening offer great opportunities for identifying high risk pregnancies.

METHODS

Through a literature search, here we summarise what are the prenatal diagnostic technique that are being used and how those techniques may allow for prenatal interventions.

RESULTS

Next generation sequencing and non-invasive prenatal testing are fundamental for clinical diagnostics because of their sensitivity and accuracy in identifying point mutations, aneuploidies, and microdeletions, respectively. Timely identification of genetic disorders and other fetal abnormalities enables early intervention, such as in-utero gene therapy, fetal drug therapy and prenatal surgery.

CONCLUSION

Prenatal intervention is mainly focused on conditions that may cause death or lifelong disabilities, like spina bifida, congenital diaphragm hernia and sacrococcygeal teratoma; and may be an alternative therapeutic option to termination of pregnancy. However, it is not yet widely available, due to lack of specialized centers.

Recent advances in our understanding of the mechanisms of lung alveolarization and bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the most common cause of morbidity and mortality in preterm infants. A key histopathological feature of BPD is stunted late lung development, where the process of alveolarization-the generation of alveolar gas exchange units-is impeded, through mechanisms that remain largely unclear. As such, there is interest in the clarification both of the pathomechanisms at play in affected lungs, and the mechanisms of de novo alveoli generation in healthy, developing lungs. A better understanding of normal and pathological alveolarization might reveal opportunities for improved medical management of affected infants. Furthermore, disturbances to the alveolar architecture are a key histopathological feature of several adult chronic lung diseases, including emphysema and fibrosis, and it is envisaged that knowledge about the mechanisms of alveologenesis might facilitate regeneration of healthy lung parenchyma in affected patients. To this end, recent efforts have interrogated clinical data, developed new-and refined existing-in vivo and in vitro models of BPD, have applied new microscopic and radiographic approaches, and have developed advanced cell-culture approaches, including organoid generation. Advances have also been made in the development of other methodologies, including single-cell analysis, metabolomics, lipidomics, and proteomics, as well as the generation and use of complex mouse genetics tools. The objective of this review is to present advances made in our understanding of the mechanisms of lung alveolarization and BPD over the period 1 January 2017-30 June 2019, a period that spans the 50th anniversary of the original clinical description of BPD in preterm infants.

Fighting the Fire: Mechanisms of Inflammatory Gene Regulation by the Glucocorticoid Receptor

For many decades, glucocorticoids have been widely used as the gold standard treatment for inflammatory conditions. Unfortunately, their clinical use is limited by severe adverse effects such as insulin resistance, cardiometabolic diseases, muscle and skin atrophies, osteoporosis, and depression. Glucocorticoids exert their effects by binding to the Glucocorticoid Receptor (GR), a ligand-activated transcription factor which both positively, and negatively regulates gene expression. Extensive research during the past several years has uncovered novel mechanisms by which the GR activates and represses its target genes. Genome-wide studies and mouse models have provided valuable insight into the molecular mechanisms of inflammatory gene regulation by GR. This review focusses on newly identified target genes and GR co-regulators that are important for its anti-inflammatory effects in innate immune cells, as well as mutations within the GR itself that shed light on its transcriptional activity. This research progress will hopefully serve as the basis for the development of safer immune suppressants with reduced side effect profiles.

Preoperative cardiopulmonary evaluation in specific neonatal surgery

Preoperative assessment of surgical neonates often relates to issues of prematurity, low birth weight, or associated malformations. This review explores the preoperative cardiopulmonary evaluation in specific newborn surgical populations, the role of echocardiography in congenital diaphragmatic hernia perioperative management, the impact of bronchopulmonary dysplasia in the ex-preterm surgical neonate and a brief discussion on the risk of general anesthesia and specific anesthetic considerations for any surgical neonate. Newborns with congenital anomalies requiring early general surgical intervention should have an assessment for congenital heart disease. In the asymptomatic neonate, a thorough physical exam may be sufficient preoperatively. Neonates born with esophageal atresia or anorectal malformations should have a full evaluation for VACTERL associations. Initial echocardiography in congenital diaphragmatic hernia is used to evaluate anatomy, but there is emerging evidence to suggest the use of echocardiography in the ongoing surveillance of CDH to influence the timing of surgical intervention. Bronchopulmonary dysplasia is present in up to 40% of ex-premature neonates and increases the risk of postoperative apneas and need for ventilatory support. However, all surgical neonates have an increased risk of post-operative apneas, and the need for surgical intervention should be balanced with the risk of general anesthesia.