Early and extended erythropoietin monotherapy after hypoxic ischaemic encephalopathy: a multicentre double-blind pilot randomised controlled trial

OBJECTIVE

To examine the feasibility of early and extended erythropoietin monotherapy after hypoxic ischaemic encephalopathy (HIE).

DESIGN

Double-blind pilot randomised controlled trial.

SETTING

Eight neonatal units in South Asia.

PATIENTS

Neonates (≥36 weeks) with moderate or severe HIE admitted between 31 December 2022 and 3 May 2023.

INTERVENTIONS

Erythropoietin (500 U/kg daily) or to the placebo (sham injections using a screen) within 6 hours of birth and continued for 9 days. MRI at 2 weeks of age.

MAIN OUTCOMES AND MEASURES

Feasibility of randomisation, drug administration and assessment of brain injury using MRI.

RESULTS

Of the 154 neonates screened, 56 were eligible; 6 declined consent and 50 were recruited; 43 (86%) were inborn. Mean (SD) age at first dose was 4.4 (1.2) hours in erythropoietin and 4.1 (1.0) hours in placebo. Overall mortality at hospital discharge occurred in 5 (19%) vs 11 (46%) (p=0.06), and 3 (13%) vs 9 (40.9%) (p=0.04) among those with moderate encephalopathy in the erythropoietin and placebo groups. Moderate or severe injury to basal ganglia, white matter and cortex occurred in 5 (25%) vs 5 (38.5%); 14 (70%) vs 11 (85%); and 6 (30%) vs 2 (15.4%) in the erythropoietin and placebo group, respectively. Sinus venous thrombosis was seen in two (10%) neonates in the erythropoietin group and none in the control group.

CONCLUSIONS

Brain injury and mortality after moderate or severe HIE are high in South Asia. Evaluation of erythropoietin monotherapy using MRI to examine treatment effects is feasible in these settings.

TRIAL REGISTRATION NUMBER

NCT05395195.

Genetic and Congenital Anomalies in Infants With Hypoxic-Ischemic Encephalopathy

BACKGROUND

Infants with hypoxic ischemic encephalopathy (HIE) may have underlying conditions predisposing them to hypoxic-ischemic injury during labor and delivery. It is unclear how genetic and congenital anomalies impact outcomes of HIE.

METHODS

Infants with HIE enrolled in a phase III trial underwent genetic testing when clinically indicated. Infants with known genetic or congenital anomalies were excluded. The primary outcome, i.e., death or neurodevelopmental impairment (NDI), was determined at age two years by a standardized neurological examination, Bayley Scales of Infant Development, Third Edition (BSID-III), and the Gross Motor Function Classification Scales. Secondary outcomes included cerebral palsy and BSID-III motor, cognitive, and language scores at age two years.

RESULTS

Of 500 infants with HIE, 24 (5%, 95% confidence interval 3% to 7%) were diagnosed with a genetic (n = 15) or congenital (n = 14) anomaly. Infants with and without genetic or congenital anomalies had similar rates of severe encephalopathy and findings on brain magnetic resonance imaging. However, infants with genetic or congenital anomalies were more likely to have death or NDI (75% vs 50%, P = 0.02). Among survivors, those with a genetic or congenital anomaly were more likely to be diagnosed with cerebral palsy (32% vs 13%, P = 0.02), and had lower BSID-III scores in all three domains than HIE survivors without such anomalies.

CONCLUSIONS

Among infants with HIE, 5% were diagnosed with a genetic or congenital anomaly. Despite similar clinical markers of HIE severity, infants with HIE and a genetic or congenital anomaly had worse neurodevelopmental outcomes than infants with HIE alone.

Evolution of the Sarnat exam and association with 2-year outcomes in infants with moderate or severe hypoxic-ischaemic encephalopathy: a secondary analysis of the HEAL Trial

OBJECTIVE

To study the association between the Sarnat exam (SE) performed before and after therapeutic hypothermia (TH) and outcomes at 2 years in infants with moderate or severe hypoxic-ischaemic encephalopathy (HIE).

DESIGN

Secondary analysis of the High-dose Erythropoietin for Asphyxia and EncephaLopathy Trial. Adjusted ORs (aORs) for death or neurodevelopmental impairment (NDI) based on SE severity category and change in category were constructed, adjusting for sedation at time of exam. Absolute SE Score and its change were compared for association with risk for death or NDI using locally estimated scatterplot smoothing curves.

SETTING

Randomised, double-blinded, placebo-controlled multicentre trial including 17 centres across the USA.

PATIENTS

479/500 enrolled neonates who had both a qualifying SE (qSE) before TH and a SE after rewarming (rSE).

INTERVENTIONS

Standardised SE was used across sites before and after TH. All providers underwent standardised SE training.

MAIN OUTCOME MEASURES

Primary outcome was defined as the composite outcome of death or any NDI at 22-36 months.

RESULTS

Both qSE and rSE were associated with the primary outcome. Notably, an aOR for primary outcome of 6.2 (95% CI 3.1 to 12.6) and 50.3 (95% CI 13.3 to 190) was seen in those with moderate and severe encephalopathy on rSE, respectively. Persistent or worsened severity on rSE was associated with higher odds for primary outcome compared with those who improved, even when qSE was severe.

CONCLUSION

Both rSE and change between qSE and rSE were strongly associated with the odds of death/NDI at 22-36 months in infants with moderate or severe HIE.

Time to regain birthweight and association with neurodevelopmental outcomes among extremely preterm newborns

OBJECTIVE

Determine association between time to regain birthweight and 2-year neurodevelopment among extremely preterm (EP) newborns.

STUDY DESIGN

Secondary analysis of the Preterm Erythropoietin Neuroprotection Trial evaluating time to regain birthweight, time from birth to weight nadir, time from nadir to regain birthweight, and cumulative weight loss with 2-year corrected Bayley Scales of Infant and Toddler Development 3rd edition.

RESULTS

Among n = 654 EP neonates, those with shorter nadir-to-regain had lower cognitive scores (≤1 day versus ≥8 days: -5.0 points, [CI -9.5, -0.6]) and lower motor scores (≤1 day versus ≥8 days: -4.6 points [CI -9.2, -0.03]) in adjusted stepwise forward regression modeling. Increasingly cumulative weight loss was associated with lower cognitive scores (≤-50 percent-days: -5.6, [CI -9.4, -1.8]), motor scores (≤-50 percent-days: -4.2, [CI -8.2, -0.2]); and language scores (≤-50 percent-days: -6.0, [CI -10.1, -1.9]).

CONCLUSION

Faster nadir-to-regain and excessive cumulative weight loss are associated with adverse 2-year neurodevelopmental outcomes.

TRIAL REGISTRATION

PENUT Trial Registration: NCT01378273. https://clinicaltrials.gov/ct2/show/NCT01378273 .

CLINICAL TRIAL REGISTRATION

This study is a post-hoc secondary analysis of pre-existing data from the PENUT Trial (NCT #01378273).

Time to Reaching Target Cooling Temperature and 2-year Outcomes in Infants with Hypoxic-Ischemic Encephalopathy

OBJECTIVE

To determine if time to reaching target temperature (TT) is associated with death or neurodevelopmental impairment (NDI) at 2 years of age in infants with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

Newborn infants ≥36 weeks of gestation diagnosed with moderate or severe HIE and treated with therapeutic hypothermia were stratified based on time at which TT was reached, defined as early (ie, ≤4 hours of age) or late (>4 hours of age). Primary outcomes were death or NDI. Secondary outcomes included neurodevelopmental assessment with Bayley Scales of Infant and Toddler Development, third edition (BSID-III) at age 2.

RESULTS

Among 500 infants, the median time to reaching TT was 4.3 hours (IWR, 3.2-5.7 hours). Infants in early TT group (n = 211 [42%]) compared with the late TT group (n = 289 [58%]) were more likely to be inborn (23% vs 13%; P < .001) and have severe HIE (28% vs 19%; P = .03). The early and late TT groups did not differ in the primary outcome of death or any NDI (adjusted RR, 1.05; 95% CI, 0.85-0.30; P = .62). Among survivors, neurodevelopmental outcomes did not differ significantly in the 2 groups (adjusted mean difference in Bayley Scales of Infant Development-III scores: cognitive, -2.8 [95% CI, -6.1 to 0.5], language -3.3 [95% CI, -7.4 to 0.8], and motor -3.5 [95% CI, -7.3 to 0.3]).

CONCLUSIONS

In infants with HIE, time to reach TT is not independently associated with risk of death or NDI at age 2 years. Among survivors, developmental outcomes are similar between those who reached TT at <4 and ≥4 hours of age.

TRIAL REGISTRATION

High-dose Erythropoietin for Asphyxia and Encephalopathy (HEAL); NCT02811263; https://beta.

CLINICALTRIALS

gov/study/NCT02811263.

Factors Associated with Outpatient Therapy Utilization in Extremely Preterm Infants

OBJECTIVE

 Factors influencing utilization of outpatient interventional therapies for extremely low gestational age newborns (ELGANs) after discharge remain poorly characterized, despite a significant risk of neurodevelopmental impairment. We sought to assess the effects of maternal, infant, and environmental characteristics on outpatient therapy utilization in the first 2 years after discharge using data from the Preterm Erythropoietin Neuroprotection (PENUT) Trial.

STUDY DESIGN

 This is a secondary analysis of 818, 24 to 27 weeks gestation infants enrolled in the PENUT trial who survived through discharge and completed at least one follow-up call or in-person visit between 4 and 24 months of age. Utilization of a state early intervention (EI) program, physical therapy (PT), occupational therapy (OT), and speech therapy (ST) was recorded. Odds ratios and cumulative frequency curves for resource utilization were calculated for patient characteristics adjusting for gestational age, treatment group, and birth weight.

RESULTS

 EI was not accessed by 37% of infants, and 18% did not use any service (PT/OT/ST/EI). Infants diagnosed with severe morbidities (intraventricular hemorrhage, retinopathy of prematurity, bronchopulmonary dysplasia, necrotizing enterocolitis), discharged with home oxygen, or with gastrostomy placement experienced increased utilization of PT, OT, and ST compared with peers. However, substantial variation in service utilization occurred by the state of enrollment and selected maternal characteristics.

CONCLUSIONS

 ELGANs with severe medical comorbidities are more likely to utilize services after discharge. Therapy utilization may be impacted by maternal characteristics and state of enrollment. Outpatient therapy services remain significantly underutilized in this high-risk cohort. Further research is required to characterize and optimize the utilization of therapy services following NICU discharge of ELGANs.

KEY POINTS

· Outpatient therapy is underutilized in ELGANs.. · Medical comorbidities may impact therapy use.. · Maternal characteristics may impact therapy use.. · State of enrollment may impact therapy use..

Relationship of Neonatal Seizure Burden Before Treatment and Response to Initial Antiseizure Medication

OBJECTIVE

To assess among a cohort of neonates with hypoxic-ischemic encephalopathy (HIE) the association of pretreatment maximal hourly seizure burden and total seizure duration with successful response to initial antiseizure medication (ASM).

STUDY DESIGN

This was a retrospective review of data collected from infants enrolled in the HEAL Trial (NCT02811263) between January 25, 2017, and October 9, 2019. We evaluated a cohort of neonates born at ≥36 weeks of gestation with moderate-to-severe HIE who underwent continuous electroencephalogram monitoring and had acute symptomatic seizures. Poisson regression analyzed associations between (1) pretreatment maximal hourly seizure burden, (2) pretreatment total seizure duration, (3) time from first seizure to initial ASM, and (4) successful response to initial ASM.

RESULTS

Among 39 neonates meeting inclusion criteria, greater pretreatment maximal hourly seizure burden was associated with lower chance of successful response to initial ASM (adjusted relative risk for each 5-minute increase in seizure burden 0.83, 95% CI 0.69-0.99). There was no association between pretreatment total seizure duration and chance of successful response. Shorter time-to-treatment was paradoxically associated with lower chance of successful response to treatment, although this difference was small in magnitude (relative risk 1.007, 95% CI 1.003-1.010).

CONCLUSIONS

Maximal seizure burden may be more important than other, more commonly used measures in predicting response to acute seizure treatments.

Contemporary definitions of infant growth failure and neurodevelopmental and behavioral outcomes in extremely premature infants at two years of age

BACKGROUND

Associations of 2-year neurodevelopmental and behavioral outcomes with growth trajectories of preterm infants are unknown.

METHODS

This secondary analysis of a preterm cohort examined in-hospital and discharge to 2-year changes in anthropometric z-scores. Two-year follow-up included Bayley Scales of Infant Development (BSID-III) and Child Behavior Checklist.

RESULTS

Among 590 infants, adjusted in-hospital growth was not associated with any BSID-III subscale. Occipitofrontal circumference (OFC) growth failure (GF) in-hospital was associated with increased adjusted odds of attention problems (aOR 1.65 [1.03, 2.65]), aggressive behavior (aOR 2.34 [1.12, 4.89]), and attention-deficit-hyperactivity symptoms (aOR 1.86 [1.05, 3.30]). Infants with OFC GF at 2 years had lower adjusted BSID-III language scores (-4.0 [-8.0, -0.1]), increased odds of attention problems (aOR 2.29 [1.11, 4.74]), aggressive behavior (aOR 3.09 [1.00, 9.56]), and externalizing problems (aOR 3.01 [1.07, 8.45]) compared to normal OFC growth cohort.

CONCLUSION

Infants with OFC GF are at risk for neurodevelopmental and behavioral impairment.

CLINICAL TRIAL REGISTRATION

This study is a secondary analysis of pre-existing data from the PENUT Trial Registration: NCT01378273.

Platelet Transfusion and Death or Neurodevelopmental Impairment in Children Born Extremely Preterm

Importance

Infants born extremely preterm receive transfusions at higher platelet count thresholds than older children and adults due to concerns for intracranial hemorrhage. A recent randomized trial comparing 2 platelet transfusion thresholds showed the higher threshold was associated with increased risk of long-term adverse neurodevelopmental outcomes.

Objective

To evaluate the association of platelet transfusion exposure with death and severe neurodevelopmental impairment (NDI) at 2 years' corrected age in a cohort of infants born extremely preterm.

Design, Setting, and Participants

An observational cohort study and secondary analysis of the Preterm Erythropoietin Neuroprotection Trial, a randomized, placebo-controlled clinical trial of erythropoietin neuroprotection in neonates born extremely preterm, was conducted in 30 neonatal intensive care units in the US from December 1, 2013, to September 31, 2016. This analysis included 819 infants born extremely preterm at 24 to 27 completed weeks of gestation who had a documented outcome (death or neurodevelopmental assessment). Analysis was performed in April 2023.

Exposures

Any platelet transfusion during neonatal intensive care unit hospitalization.

Main Outcomes and Measures

The primary composite outcome was death or severe NDI evaluated at 2 years' corrected age using the Bayley Scales of Infant Development-Third Edition (BSID-III) and the Gross Motor Function Classification System and was defined as the presence of severe cerebral palsy or a BSID-III composite motor or cognitive score 2 SDs below the mean. Confounding by indication for platelet transfusion was addressed with covariate adjustment and propensity score methods.

Results

Of the 819 infants included in the analysis (429 [52.4%] male; mean [SD] gestational age, 25.5 [1.1] weeks), 245 (30.0%) received at least 1 platelet transfusion during their initial hospitalization. The primary outcome occurred in 46.5% (114 of 245) of infants exposed to a platelet transfusion and 13.9% (80 of 574) of nonexposed infants with a corresponding odds ratio of 2.43 (95% CI, 1.24-4.76), adjusted for propensity score, gestational age at birth, and trial treatment group. The individual components of death and severe NDI were directionally consistent with the overall composite outcome.

Conclusions and Relevance

The findings of this study suggest that platelet transfusion in infants born extremely preterm may be associated with an increased risk of death or severe NDI at 2 years' corrected age, although the possibility of residual confounding by indication cannot be excluded.

Rectal temperature after hypoxia-ischemia predicts white matter and cortical pathology in the near-term ferret

BACKGROUND

Neonatal encephalopathy (NE) remains a common cause of infant morbidity and mortality. Neuropathological corollaries of NE associated with acute hypoxia-ischemia include a central injury pattern involving the basal ganglia and thalamus, which may interfere with thermoregulatory circuits. Spontaneous hypothermia (SH) occurs in both preclinical models and clinical hypoxic-ischemic NE and may provide an early biomarker of injury severity. To determine whether SH predicts the degree of injury in a ferret model of hypoxic-ischemic NE, we investigated whether rectal temperature (RT) 1 h after insult correlated with long-term outcomes.

METHODS

Postnatal day (P)17 ferrets were presensitized with Escherichia coli lipopolysaccharide before undergoing hypoxia-ischemia/hyperoxia (HIH): bilateral carotid artery ligation, hypoxia-hyperoxia-hypoxia, and right ligation reversal. One hour later, nesting RTs were measured.

RESULTS

Animals exposed to HIH were separated into normothermic (NT; ≥34.4 °C) or spontaneously hypothermic (SH; <34.4 °C) groups. At P42, cortical development, ex vivo MRI, and neuropathology were quantitated. Whole-brain volume and fractional anisotropy in SH brains were significantly decreased compared to control and NT animals. SH brains also had significantly altered gyrification, greater cortical pathology, and increased corpus callosum GFAP staining relative to NT and control brains.

CONCLUSION

In near-term-equivalent ferrets, nesting RT 1 h after HIH may predict long-term neuropathological outcomes.

IMPACT

High-throughput methods to determine injury severity prior to treatment in animal studies of neonatal brain injury are lacking. In a gyrified animal model of neonatal inflammation-sensitized hypoxic-ischemic brain injury in the ferret, rectal temperature 1 h after hypoxia predicts animals who will have increased cortical pathology and white matter changes on MRI. These changes parallel similar responses in rodents and humans but have not previously been correlated with long-term neuropathological outcomes in gyrified animal models. Endogenous thermoregulatory responses to injury may provide a translational marker of injury severity to help stratify animals to treatment groups or predict outcome in preclinical studies.

Darbepoetin alfa to reduce transfusion episodes in infants with haemolytic disease of the fetus and newborn who are treated with intrauterine transfusions in the Netherlands: an open-label, single-centre, phase 2, randomised, controlled trial

BACKGROUND

Up to 88% of infants with haemolytic disease of the fetus and newborn who are treated with intrauterine transfusions require erythrocyte transfusions after birth. We aimed to investigate the effect of darbepoetin alfa on the prevention of postnatal anaemia in infants with haemolytic disease of the fetus and newborn.

METHODS

We conducted an open-label, single-centre, phase 2 randomised controlled trial to evaluate the effect of darbepoetin alfa on the number of erythrocyte transfusions in infants with haemolytic disease of the fetus and newborn. All infants who were treated with intrauterine transfusion and born at 35 weeks of gestation or later at the Leiden University Medical Center, Leiden, Netherlands, were eligible for inclusion. Included infants were randomised by computer at birth to treatment with 10 μg/kg darbepoetin alfa subcutaneously once a week for 8 weeks or standard care (1:1 allocation, in varying blocks of four and six, with no stratification). Treating physicians and parents were not masked to treatment allocation, but the research team, data manager, and statistician were masked to treatment allocation during the process of data collection. The primary outcome was the number of erythrocyte transfusion episodes per infant from birth up to 3 months of life in the modified intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT03104426) and has been completed.

FINDINGS

Between Oct 31, 2017, and April 31, 2022, we recruited 76 infants, of whom 44 (58%) were randomly assigned to a treatment group (20 [45%] were allocated to receive darbepoetin alfa and 24 [55%] were allocated to receive standard care). Follow-up lasted 3 months and one infant dropped out of the trial before commencement of treatment. A significant reduction in erythrocyte transfusion episodes was identified with darbepoetin alfa treatment compared with standard care (median 1·0 [IQR 1·0-2·0] transfusion episodes vs 2·0 [1·3-3·0] transfusion episodes; p=0·0082). No adverse events were reported and no infants died during the study.

INTERPRETATION

Darbepoetin alfa reduced the transfusion episodes after intrauterine transfusion treatment for haemolytic disease of the fetus and newborn. Treatment with darbepoetin alfa or other types of erythropoietin should be considered as part of the postnatal treatment of severe haemolytic disease of the fetus and newborn.

FUNDING

Sanquin Blood Supply.

TRANSLATION

For the Dutch translation of the abstract see Supplementary Materials section.

Association of EEG Background and Neurodevelopmental Outcome in Neonates With Hypoxic-Ischemic Encephalopathy Receiving Hypothermia

BACKGROUND AND OBJECTIVES

Predicting neurodevelopmental outcome for neonates with hypoxic-ischemic encephalopathy (HIE) is important for clinical decision-making, care planning, and parent communication. We examined the relationship between EEG background and neurodevelopmental outcome among children enrolled in a trial of erythropoietin or placebo for neonates with HIE treated with therapeutic hypothermia.

METHODS

Participants had EEG recorded throughout hypothermia. EEG background was classified as normal, discontinuous, or severely abnormal (defined as burst suppression, low voltage suppressed, or status epilepticus) at 5 1-hour epochs: onset of recording, 24, 36, 48, and 72 hours after birth. The predominant background pattern during the entire continuous video EEG monitoring recording was calculated using the arithmetic mean of the 5 EEG background ratings (normal = 0; discontinuous = 1; severely abnormal = 2) as follows: "predominantly normal" (mean = 0), "normal/discontinuous" (0 < mean<1), "predominantly discontinuous" (mean = 1), "discontinuous/severely abnormal" (1 < mean<2), or "predominantly severely abnormal" (mean = 2). Primary outcome was death or neurodevelopmental impairment (NDI) defined as cerebral palsy, Gross Motor Function Classification Score ≥1, or cognitive score <90 on Bayley Scales of Infant Toddler Development, third edition at age 2 years. Neurodevelopment was also categorized into a 5-level ordinal measure: no, mild, moderate, severe NDI, or death for secondary analysis. We used generalized linear regression models with robust standard errors to assess the relative risk of death or NDI by EEG background in both unadjusted and adjusted analyses controlling for the effects of treatment group, sex, HIE severity, and study recruitment site.

RESULTS

Among 142 neonates, the predominant background EEG pattern was predominantly normal in 35 (25%), normal/discontinuous in 68 (48%), predominantly discontinuous in 11 (7.7%), discontinuous/severely abnormal in 16 (11%), and predominantly severely abnormal in 12 (8.5%). Increasing severity of background across monitoring epochs was associated with increasingly worse clinical outcomes. Children with severe EEG background abnormality at any time point (n = 36, 25%) were significantly more likely to die or have severe NDI at 2 years (adjusted relative risk: 7.95, 95% CI 3.49-18.12).

DISCUSSION

EEG background is strongly associated with NDI at age 2 years. These results can be used to assist health care providers to plan follow-up care and counsel families for decision-making related to goals of care.

New frontiers in neonatal red blood cell transfusion research

Red blood cell (RBC) transfusions are common in neonates requiring intensive care. Recent studies have compared restricted versus liberal transfusion guidelines, but limitations exist on evaluations of outcomes in populations that never required a transfusion compared to those receiving any transfusion. Although there are well-established risks associated with RBC transfusions, new data has emerged that suggests additional clinically relevant associations, including adverse neurodevelopmental outcomes, donor sex differences, and inflammation or immunosuppression. Further research is needed to delineate the magnitude of these risks and to further improve the safety of transfusions. The goal of this review is to highlight underappreciated, yet clinically important risks associated with neonatal RBC transfusions and to introduce several areas in which neonates may uniquely benefit from alterations in practice.

Brain Injury Outcomes after Adjuvant Erythropoietin Neuroprotection for Moderate or Severe Neonatal Hypoxic-Ischemic Encephalopathy: A Report from the HEAL Trial

INTRODUCTION

Erythropoietin (Epo) is a putative neuroprotective therapy that did not improve overall outcomes in a phase 3 randomized controlled trial for neonates with moderate or severe hypoxic-ischemic encephalopathy (HIE). However, HIE is a heterogeneous disorder, and it remains to be determined whether Epo had beneficial effects on a subset of perinatal brain injuries.

METHODS

This study was a secondary analysis of neuroimaging data from the High-dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) Trial, which was conducted from 2016 - 2021 at 17 sites involving 23 US academic medical centers. Participants were neonates >36 weeks' gestation undergoing therapeutic hypothermia for moderate or severe HIE who received 5 doses of study drug (Epoetin alpha 1000 U/kg/dose) or placebo in the first week of life. Treatment assignment was stratified by trial site and severity of encephalopathy. The primary outcome was the locus, pattern and acuity of brain injury as determined by three independent readers using a validated HIE Magnetic Resonance Imaging (MRI) scoring system.

RESULTS

Of the 500 infants enrolled in HEAL, 470 (94%) had high quality MRI data obtained at a median of 4.9 days of age (IQR 4.5 - 5.8). The incidence of injury to the deep grey nuclei, cortex, white matter, brainstem and cerebellum was similar between Epo and placebo groups. Likewise, the distribution of injury patterns was similar between groups. Among infants imaged at less than 8 days (n=414), 94 (23%) evidenced only acute, 93 (22%) only subacute and 89 (21%) both acute and subacute injuries, with similar distribution across treatment groups.

CONCLUSION

Adjuvant erythropoietin did not reduce the incidence of regional brain injury. Subacute brain injury was more common than previously reported, which has key implications for the development of adjuvant neuroprotective therapies for this population.

Placental Histologic Abnormalities and 2-Year Outcomes in Neonatal Hypoxic-Ischemic Encephalopathy

OBJECTIVE

We aimed to examine the association between placental abnormalities and neurodevelopmental outcomes in a multicenter cohort of newborn infants with hypoxic-ischemic encephalopathy (HIE) that underwent therapeutic hypothermia. We hypothesized that subjects with acute placental abnormalities would have reduced risk of death or neurodevelopmental impairment (NDI) at 2 years of age after undergoing therapeutic hypothermia compared to subjects without acute placental changes.

STUDY DESIGN

Among 500 subjects born at ≥36 weeks gestation with moderate or severe HIE enrolled in the High-dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) Trial, a placental pathologist blinded to clinical information reviewed clinical pathology reports to determine the presence of acute only, chronic only, or both acute and chronic histologic abnormalities. We calculated adjusted relative risks (aRRs) for associations between placental pathologic abnormalities and death or NDI at age 2 years, adjusting for HIE severity, treatment assignment, and site.

RESULT

321/500 subjects (64%) had available placental pathology reports. Placental abnormalities were characterized as acute only (20%), chronic only (21%), both acute and chronic (43%), and none (15%). The risk of death or NDI was not statistically different between subjects with and without an acute placental abnormality (46 vs. 53%, aRR 1.1, 95% confidence interval (CI): 0.9, 1.4). Subjects with two or more chronic lesions were more likely to have an adverse outcome than subjects with no chronic abnormalities, though this did not reach statistical significance (55 vs. 45%, aRR 1.24, 95% CI: 0.99, 1.56).

CONCLUSION

Placental pathologic findings were not independently associated with risk of death or NDI in subjects with HIE. The relationship between multiple chronic placental lesions and HIE outcomes deserves further study.

How well does neonatal neuroimaging correlate with neurodevelopmental outcomes in infants with hypoxic-ischemic encephalopathy?

BACKGROUND

In newborns with hypoxic-ischemic encephalopathy (HIE), the correlation between neonatal neuroimaging and the degree of neurodevelopmental impairment (NDI) is unclear.

METHODS

Infants with HIE enrolled in a randomized controlled trial underwent neonatal MRI/MR spectroscopy (MRS) using a harmonized protocol at 4-6 days of age. The severity of brain injury was measured with a validated scoring system. Using proportional odds regression, we calculated adjusted odds ratios (aOR) for the associations between MRI/MRS measures of injury and primary ordinal outcome (i.e., normal, mild NDI, moderate NDI, severe NDI, or death) at age 2 years.

RESULTS

Of 451 infants with MRI/MRS at a median age of 5 days (IQR 4.5-5.8), outcomes were normal (51%); mild (12%), moderate (14%), severe NDI (13%); or death (9%). MRI injury score (aOR 1.06, 95% CI 1.05, 1.07), severe brain injury (aOR 39.6, 95% CI 16.4, 95.6), and MRS lactate/n-acetylaspartate (NAA) ratio (aOR 1.6, 95% CI 1.4,1.8) were associated with worse primary outcomes. Infants with mild/moderate MRI brain injury had similar BSID-III cognitive, language, and motor scores as infants with no injury.

CONCLUSION

In the absence of severe injury, brain MRI/MRS does not accurately discriminate the degree of NDI. Given diagnostic uncertainty, families need to be counseled regarding a range of possible neurodevelopmental outcomes.

IMPACT

Half of all infants with hypoxic-ischemic encephalopathy (HIE) enrolled in a large clinical trial either died or had neurodevelopmental impairment at age 2 years despite receiving therapeutic hypothermia. Severe brain injury and a global pattern of brain injury on MRI were both strongly associated with death or neurodevelopmental impairment. Infants with mild or moderate brain injury had similar mean BSID-III cognitive, language, and motor scores as infants with no brain injury on MRI. Given the prognostic uncertainty of brain MRI among infants with less severe degrees of brain injury, families should be counseled regarding a range of possible neurodevelopmental outcomes.

Correlating Quantitative MRI-based Apparent Diffusion Coefficient Metrics with 24-month Neurodevelopmental Outcomes in Neonates from the HEAL Trial

Background Multiple qualitative scoring systems have been created to capture the imaging severity of hypoxic ischemic brain injury. Purpose To evaluate quantitative volumes of acute brain injury at MRI in neonates with hypoxic ischemic brain injury and correlate these findings with 24-month neurodevelopmental outcomes and qualitative brain injury scoring by radiologists. Materials and Methods In this secondary analysis, brain diffusion-weighted MRI data from neonates in the High-dose Erythropoietin for Asphyxia and Encephalopathy trial, which recruited participants between January 2017 and October 2019, were analyzed. Volume of acute brain injury, defined as brain with apparent diffusion coefficient (ADC) less than 800 × 10-6 mm2/sec, was automatically computed across the whole brain and within the thalami and white matter. Outcomes of death and neurodevelopmental impairment (NDI) were recorded at 24-month follow-up. Associations between the presence and volume (in milliliters) of acute brain injury with 24-month outcomes were evaluated using multiple logistic regression. The correlation between quantitative acute brain injury volume and qualitative MRI scores was assessed using the Kendall tau-b test. Results A total of 416 neonates had available MRI data (mean gestational age, 39.1 weeks ± 1.4 [SD]; 235 male) and 113 (27%) showed evidence of acute brain injury at MRI. Of the 387 participants with 24-month follow-up data, 185 (48%) died or had any NDI. Volume of acute injury greater than 1 mL (odds ratio [OR], 13.9 [95% CI: 5.93, 32.45]; P < .001) and presence of any acute injury in the brain (OR, 4.5 [95% CI: 2.6, 7.8]; P < .001) were associated with increased odds of death or any NDI. Quantitative whole-brain acute injury volume was strongly associated with radiologists' qualitative scoring of diffusion-weighted images (Kendall tau-b = 0.56; P < .001). Conclusion Automated quantitative volume of brain injury is associated with death, moderate to severe NDI, and cerebral palsy in neonates with hypoxic ischemic encephalopathy and correlated well with qualitative MRI scoring of acute brain injury. Clinical trial registration no. NCT02811263 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Huisman in this issue.

Reducing Severe Intraventricular Hemorrhage in Preterm Infants With Improved Care Bundle Adherence

BACKGROUND AND OBJECTIVES

Intraventricular hemorrhage prevention bundles (IVHPBs) can decrease the incidence of intraventricular hemorrhage (IVH) in premature infants. Our center had a high rate of severe (grade III/IV) IVH (9.8%), and poor adherence (24%) to an IVHPB in neonates born ≤1250 g or ≤30 gestational weeks. Improvement initiatives were planned to decrease the incidence of severe IVH by 30% over 2 years.

METHODS

A multidisciplinary team undertook interventions including in-service training, prompt initiation of IVHPB, revision of guidelines, and process standardization. Baseline data were collected from May 2016 to June 2018, with interventions occurring from July 2018 to May 2020. Adherence to the IVHPB was the primary process measure, and incidence of severe IVH the primary outcome measure. Control charts were used to analyze the effect of interventions on outcome. Balancing measures included use of breast milk at discharge, use of mechanical ventilation after initial resuscitation, and bronchopulmonary dysplasia.

RESULTS

A total of 240 infants were assessed preintervention, and 185 during interventions. Adherence to the IVHPB improved from 24% to 88%. During this period, the incidence of severe IVH decreased from 9.8% to 2.4%, a 76% reduction from baseline. A higher adherence score was associated with reduced odds of IVH (odds ratio 0.30; 95% confidence interval 0.10-0.90, P = .03).

CONCLUSIONS

Interventions focused on enhancing adherence to an IVHPB were associated with a reduced rate of severe IVH in high-risk neonates, highlighting the importance of assessing adherence to clinical guidelines.

Evaluation of neurovascular coupling during neuroprotective therapies: A single site HEAL ancillary study

BACKGROUND

There is a critical need for development of physiological biomarkers in infants with birth asphyxia to identify the physiologic response to therapies in real time. This is an ancillary single site study of the High-Dose Erythropoietin for Asphyxia and Encephalopathy (Wu et al., 2022 [1]) to measure neurovascular coupling (NVC) non-invasively during an ongoing blinded randomized trial.

METHODS

Neonates who randomized in the HEAL enrolled at a single-center Level III Neonatal Intensive Care Unit were recruited between 2017 and 2019. Neurodevelopmental impairment was blinded and defined as any of the following: cognitive score <90 on Bayley Scales of Infant Toddler Development, third edition (BSID-III), Gross Motor Function Classification Score (GMFCS) ≥1.

RESULTS

All twenty-seven neonates enrolled in HEAL were recruited and 3 died before complete recording. The rank-based analysis of covariance models demonstrated lack of difference in NVC between the two groups (Epo versus Placebo) that was consistent with the observed lack of effect on neurodevelopmental outcomes.

CONCLUSION

We demonstrate no difference in neurovascular coupling after Epo administration. These findings are consistent with overall negative trial results. Physiological biomarkers can help elucidate mechanisms of neuroprotective therapies in real time in future trials.

Premature infants born <28 weeks with acute kidney injury have increased bronchopulmonary dysplasia rates

BACKGROUND

Despite a growing understanding of bronchopulmonary dysplasia (BPD) and advances in management, BPD rates remain stable. There is mounting evidence that BPD may be due to a systemic insult, such as acute kidney injury (AKI). Our hypothesis was that severe AKI would be associated with BPD.

METHODS

We conducted a secondary analysis of premature infants [24-27 weeks gestation] in the Recombinant Erythropoietin for Protection of Infant Renal Disease cohort (N = 885). We evaluated the composite outcome of Grade 2/3 BPD or death using generalized estimating equations. In an exploratory analysis, urinary biomarkers of angiogenesis (ANG1, ANG2, EPO, PIGF, TIE2, FGF, and VEGFA/D) were analyzed.

RESULTS

594 (67.1%) of infants had the primary composite outcome of Grade 2/3 BPD or death. Infants with AKI (aOR: 1.69, 95% CI: 1.16-2.46) and severe AKI (aOR: 2.05, 95% CI: 1.19-3.54). had increased risk of the composite outcome after multivariable adjustment Among 106 infants with urinary biomarkers assessed, three biomarkers (VEGFA, VEGFD, and TIE2) had AUC > 0.60 to predict BPD.

CONCLUSIONS

Infants with AKI had a higher likelihood of developing BPD/death, with the strongest relationship seen in those with more severe AKI. Three urinary biomarkers of angiogenesis may have potential to predict BPD development.

IMPACT

AKI is associated with lung disease in extremely premature infants, and urinary biomarkers may predict this relationship. Infants with AKI and severe AKI have higher odds of BPD or death. Three urinary angiogenesis biomarkers are altered in infants that develop BPD. These findings have the potential to drive future work to better understand the mechanistic pathways of BPD, setting the framework for future interventions to decrease BPD rates. A better understanding of the mechanisms of BPD development and the role of AKI would have clinical care, cost, and quality of life implications given the long-term effects of BPD.

Association of High-Dose Erythropoietin With Circulating Biomarkers and Neurodevelopmental Outcomes Among Neonates With Hypoxic Ischemic Encephalopathy: A Secondary Analysis of the HEAL Randomized Clinical Trial

Importance

The ability to predict neurodevelopmental impairment (NDI) for infants diagnosed with hypoxic ischemic encephalopathy (HIE) is important for parental guidance and clinical treatment as well as for stratification of patients for future neurotherapeutic studies.

Objectives

To examine the effect of erythropoietin on plasma inflammatory mediators in infants with moderate or severe HIE and to develop a panel of circulating biomarkers that improves the projection of 2-year NDI over and above the clinical data available at the time of birth.

Design, Setting, and Participants

This study is a preplanned secondary analysis of prospectively collected data from infants enrolled in the High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) Trial, which tested the efficacy of erythropoietin as an adjunctive neuroprotective therapy to therapeutic hypothermia. The study was conducted at 17 academic sites comprising 23 neonatal intensive care units in the United States between January 25, 2017, and October 9, 2019, with follow-up through October 2022. Overall, 500 infants born at 36 weeks' gestation or later with moderate or severe HIE were included.

Intervention

Erythropoietin treatment 1000 U/kg/dose on days 1, 2, 3, 4 and 7.

Main Outcomes and Measures

Plasma erythropoietin was measured in 444 infants (89%) within 24 hours after birth. A subset of 180 infants who had plasma samples available at baseline (day 0/1), day 2, and day 4 after birth and either died or had 2-year Bayley Scales of Infant Development III assessments completed were included in the biomarker analysis.

Results

The 180 infants included in this substudy had a mean (SD) gestational age of 39.1 (1.5) weeks, and 83 (46%) were female. Infants who received erythropoietin had increased concentrations of erythropoietin at day 2 and day 4 compared with baseline. Erythropoietin treatment did not alter concentrations of other measured biomarkers (eg, difference in interleukin [IL] 6 between groups on day 4: -1.3 pg/mL; 95% CI, -4.8 to 2.0 pg/mL). After adjusting for multiple comparisons, we identified 6 plasma biomarkers (C5a, interleukin [IL] 6, and neuron-specific enolase at baseline; IL-8, tau, and ubiquitin carboxy-terminal hydrolase-L1 at day 4) that significantly improved estimations of death or NDI at 2 years compared with clinical data alone. However, the improvement was only modest, increasing the AUC from 0.73 (95% CI, 0.70-0.75) to 0.79 (95% CI, 0.77-0.81; P = .01), corresponding to a 16% (95% CI, 5%-44%) increase in correct classification of participant risk of death or NDI at 2 years.

Conclusions and Relevance

In this study, erythropoietin treatment did not reduce biomarkers of neuroinflammation or brain injury in infants with HIE. Circulating biomarkers modestly improved estimation of 2-year outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT02811263.

Risk of seizures in neonates with hypoxic-ischemic encephalopathy receiving hypothermia plus erythropoietin or placebo

BACKGROUND

An ancillary study of the High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) trial for neonates with hypoxic-ischemic encephalopathy (HIE) and treated with therapeutic hypothermia examined the hypothesis that neonates randomized to receive erythropoietin (Epo) would have a lower seizure risk and burden compared with neonates who received placebo.

METHODS

Electroencephalograms (EEGs) from 7/17 HEAL trial centers were reviewed. Seizure presence was compared across treatment groups using a logistic regression model adjusting for treatment, HIE severity, center, and seizure burden prior to the first dose. Among neonates with seizures, differences across treatment groups in median maximal hourly seizure burden were assessed using adjusted quantile regression models.

RESULTS

Forty-six of 150 (31%) neonates had EEG seizures (31% in Epo vs 30% in placebo, p = 0.96). Maximal hourly seizure burden after the study drug was not significantly different between groups (median 11.4 for Epo, IQR: 5.6, 18.1 vs median 9.7, IQR: 4.9, 21.0 min/h for placebo).

CONCLUSION

In neonates with HIE treated with hypothermia who were randomized to Epo or placebo, we found no meaningful between-group difference in seizure risk or burden. These findings are consistent with overall trial results, which do not support Epo use for neonates with HIE undergoing therapeutic hypothermia.

IMPACT

In the HEAL trial of erythropoietin (Epo) vs placebo for neonates with encephalopathy presumed due to hypoxic-ischemic encephalopathy (HIE) who were also treated with therapeutic hypothermia, electrographic seizures were detected in 31%, which is lower than most prior studies. Epo did not reduce the proportion of neonates with acute provoked seizures (31% in Epo vs 30% in placebo) or maximal hourly seizure burden after the study drug (median 11.4, IQR 5.6, 18.1 for Epo vs median 9.7, IQR 4.9, 21.0 min/h for placebo). There was no anti- or pro-convulsant effect of Epo when combined with therapeutic hypothermia for HIE.

Temperature dysregulation during therapeutic hypothermia predicts long-term outcome in neonates with HIE

Few reliable or easily obtainable biomarkers to predict long-term outcome in infants with hypoxic-ischemic encephalopathy (HIE) have been identified. We previously showed that mattress temperature (MT), as proxy for disturbed temperature regulation during therapeutic hypothermia (TH), predicts injury on early MRI and holds promise as physiologic biomarker. To determine whether MT in neonates treated with TH for moderate-severe HIE is associated with long-term outcome at 18-22 months, we performed a secondary analysis of the Optimizing Cooling trial using MT data from 167 infants treated at a core temperature of 33.5°C. Median MTs from four time-epochs (0-6 h, 6-24 h, 24-48 h, and 48-72 h of TH) were used to predict death or moderate-severe neurodevelopmental impairment (NDI), using epoch-specific derived and validated MT cutoffs. Median MT of infants who died or survived with NDI was consistently 1.5-3.0°C higher throughout TH. Infants requiring a median MT above the derived cut-offs had a significantly increased odds of death or NDI, most notably at 0-6 h (aOR 17.0, 95%CI 4.3-67.4). By contrast, infants who remained below cut-offs across all epochs had 100% NDI-free survival. MTs in neonates with moderate-severe HIE during TH are highly predictive of long-term outcome and can be used as physiologic biomarker.

Safety of High Dose Erythropoietin Used with Therapeutic Hypothermia as Treatment for Newborn Hypoxic-Ischemic Encephalopathy: Secondary Analysis of the HEAL Randomized Controlled Trial

OBJECTIVE

To assess whether high dose erythropoietin (Epo) treatment of cooled infants with neonatal hypoxic ischemic encephalopathy results in a higher risk of prespecified serious adverse events (SAEs).

STUDY DESIGN

Five hundred infants born at ≥36 weeks of gestation with moderate or severe hypoxic ischemic encephalopathy undergoing therapeutic hypothermia were randomized to Epo or placebo on days 1, 2, 3, 4, and 7. Pretreatment and posttreatment SAEs were compared with adjusted generalized linear models, with posttreatment models adjusted for the presence of a pretreatment SAE. Clinical risk factors and potential mechanisms for SAEs were also examined.

RESULTS

The rate of experiencing at least one posttreatment SAE did not significantly differ between groups (adjusted relative risk [aRR], 95% CI: 1.17, 0.92-1.49); however, posttreatment thrombosis was identified more often in the Epo group (n = 6, 2.3%) than the placebo group (n = 1, 0.4%; aRR, 95% CI: 5.09, 1.32-19.64). The rate of posttreatment intracranial hemorrhage identified at the treatment sites by either ultrasound or magnetic resonance imaging was slightly elevated in the Epo group (n = 61, 24%) but not significantly different from the placebo group (n = 46, 19%; aRR, 95% CI: 1.21, 0.85, 1.72).

CONCLUSIONS

A small increased risk of major thrombotic events was identified in the Epo treatment group.

TRIAL REGISTRATION

NCT02811263.

Maternal Nutritional Status and the Microbiome across the Pregnancy and the Post-Partum Period

Appropriate nutrition during pregnancy and the post-partum period is vital for both the mothers and their offspring. Both under- and over-nourished status may have important microbial implications on the maternal and infant gut microbiomes. Alterations in the microbiome can have implications for a person's risk of obesity and metabolic diseases. In this review, we examine alterations in the maternal gut, vaginal, placental, and milk microbiomes in the context of pre-pregnancy BMI, gestational weight gain, body composition, gestational diabetes, and maternal diet. We also investigate how the infant gut microbiome may be altered by these different parameters. Many of the microbial changes seen in under- and over-nourished states in birthing parents may result in long-term implications for the health of offspring. Differences in diet appear to be a major driver of the maternal and subsequently milk and offspring microbiomes. Further prospective longitudinal cohort studies are needed to examine nutrition and the microbiome to better understand its implications. Additionally, trials involving dietary interventions in child-bearing age adults should be explored to improve the mother and child's risks for metabolic diseases.

Patterns of Infections among Extremely Preterm Infants

Infections remain a leading cause of neonatal death, especially among the extremely preterm infants. To evaluate the incidence, pathogenesis, and in-hospital outcomes associated with sepsis among hospitalized extremely preterm infants born at 24-0/7 to 27-6/7 weeks of gestation, we designed a post hoc analysis of data collected prospectively during the Preterm Epo Neuroprotection (PENUT) Trial, NCT #01378273. We analyzed culture positive infection data, as well as type and duration of antibiotic course and described their association with in-hospital morbidities and mortality. Of 936 included infants, 229 (24%) had at least one positive blood culture during their hospitalization. Early onset sepsis (EOS, ≤3 days after birth) occurred in 6% of the infants, with Coagulase negative Staphylococci (CoNS) and Escherichia Coli the most frequent pathogens. Late onset sepsis (LOS, >day 3) occurred in 20% of the infants. Nearly all infants were treated with antibiotics for presumed sepsis at least once during their hospitalization. The risk of confirmed or presumed EOS was lower with increasing birthweight. Confirmed EOS had no significant association with in-hospital outcomes or death while LOS was associated with increased risk of necrotizing enterocolitis and death. Extremely premature infants with presumed sepsis as compared to culture positive sepsis had lower rates of morbidities. In conclusion, the use of antibiotics for presumed sepsis remains much higher than confirmed infection rates. Ongoing work exploring antibiotic stewardship and presumed, culture-negative sepsis in extremely preterm infants is needed.

Urine acute kidney injury biomarkers in extremely low gestational age neonates: a nested case control study of 21 candidate urine biomarkers

BACKGROUND

Acute kidney injury (AKI) is common and is associated with poor clinical outcomes in premature neonates. Urine biomarkers hold the promise to improve our understanding and care of patients with kidney disease. Because kidney maturation and gender can impact urine biomarker values in extremely low gestational age neonates (ELGANs), careful control of gestational age (GA) and time is critical to any urine biomarker studies in neonates.

METHODS

To improve our understanding of the potential use of urine biomarkers to detect AKI during the first postnatal weeks, we performed a nested case-control study to evaluate 21 candidate urine AKI biomarkers. Cases include 20 ELGANs with severe AKI. Each case was matched with 2 controls for the same GA week (rounded down to the nearest week), gender, and birth weight (BW) (± 50 g).

RESULTS

Urine cystatin C, creatinine, ghrelin, fibroblast growth factor-23 (FGF23), tissue metalloproteinase 2 (TIMP2) and vascular endothelial growth factor A (VEGFa) concentrations were higher in ELGANs with early severe AKI compared to matched control subjects without AKI. Urine epidermal growth factor (EGF) and uromodulin (UMOD) concentrations are lower in cases than controls. Interleukin (IL)-15 was lower on day 1, but higher on day 8 in cases than controls; while VEGFa was lower on day 1, but higher on day 5 in cases than controls.

CONCLUSION

Urine biomarkers hold the promise to improve our ability to reliably detect kidney injury. Interventional studies are needed to determine the biomarkers' ability to predict outcomes, enhance AKI phenotypes, and improve timely interventions which can prevent the sequalae of AKI in ELGANs. A higher resolution version of the Graphical abstract is available as Supplementary information.

Predicting 2-year neurodevelopmental outcomes in extremely preterm infants using graphical network and machine learning approaches

Background

Infants born extremely preterm (<28 weeks' gestation) are at high risk of neurodevelopmental impairment (NDI) with 50% of survivors showing moderate or severe NDI when at 2 years of age. We sought to develop novel models by which to predict neurodevelopmental outcomes, hypothesizing that combining baseline characteristics at birth with medical care and environmental exposures would produce the most accurate model.

Methods

Using a prospective database of 692 infants from the Preterm Epo Neuroprotection (PENUT) Trial, which was carried out between December 2013 and September 2016, we developed three predictive algorithms of increasing complexity using a Bayesian Additive Regression Trees (BART) machine learning approach to predict both NDI and continuous Bayley Scales of Infant and Toddler Development 3rd ed subscales at 2 year follow-up using: 1) the 5 variables used in the National Institute of Child Health and Human Development (NICHD) Extremely Preterm Birth Outcomes Tool, 2) 21 variables associated with outcomes in extremely preterm (EP) infants, and 3) a hypothesis-free approach using 133 potential variables available for infants in the PENUT database.

Findings

The NICHD 5-variable model predicted 3-4% of the variance in the Bayley subscale scores, and predicted NDI with an area under the receiver operator curve (AUROC, 95% CI) of 0.62 (0.56-0.69). Accuracy increased to 12-20% of variance explained and an AUROC of 0.77 (0.72-0.83) when using the 21 pre-selected clinical variables. Hypothesis-free variable selection using BART resulted in models that explained 20-31% of Bayley subscale scores and AUROC of 0.87 (0.83-0.91) for severe NDI, with good calibration across the range of outcome predictions. However, even with the most accurate models, the average prediction error for the Bayley subscale predictions was around 14-15 points, leading to wide prediction intervals. Higher total transfusion volume was the most important predictor of severe NDI and lower Bayley scores across all subscales.

Interpretation

While the machine learning BART approach meaningfully improved predictive accuracy above a widely used prediction tool (NICHD) as well as a model utilizing NDI-associated clinical characteristics, the average error remained approximately 1 standard deviation on either side of the true value. Although dichotomous NDI prediction using BART was more accurate than has been previously reported, and certain clinical variables such as transfusion exposure were meaningfully predictive of outcomes, our results emphasize the fact that the field is still not able to accurately predict the results of complex long-term assessments such as Bayley subscales in infants born EP even when using rich datasets and advanced analytic methods. This highlights the ongoing need for long-term follow-up of all EP infants.

Funding

Supported by the National Institute of Neurological Disorders and StrokeU01NS077953 and U01NS077955.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TRIAL REGISTRATION NUMBER

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

Factors That Impact Hospital-Specific Enrollment Rates for a Neonatal Clinical Trial: An Analysis of the HEAL Study

Inconsistent enrollment among hospitals for neonatal clinical trials may lead to study populations that are not representative of the patient population in the neonatal intensive care unit. The High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) trial was a multisite randomized clinical trial investigating erythropoietin as a neuroprotective treatment for term infants (those born between 37 and 42 complete weeks) with hypoxic ischemic encephalopathy. Substantial variability was noted in enrollment rate by hospital. We developed survey questions across five conceptual domains to understand systems-level issues that might contribute to variation in enrollment rate by hospital. Our study found that hospitals varied in their responses across these five domains. We propose three potential reasons that we found a lack of identifiable hospital-level factors that correlated with enrollment rates: sample-size limitations, methodological concerns, and confounding factors. Future studies with a larger sample size should be considered to evaluate contributors to hospital-level variability. This will lead to more robust recruitment strategies, improved enrollment, and decreases in the waste of research resources.

Neonatal Anemia

All neonates experience a downtrend in their hematocrit values immediately following the birth through normal falls in erythropoietin (Epo) production, transition to adult hemoglobin, and hemodilution with somatic growth. However, this drop is more pronounced in critically ill and preterm neonates and can lead to potentially pathologic anemia that impairs tissue oxygen delivery. In this review, we highlight the mechanisms underlying physiologic anemia and anemia of prematurity and briefly review the evidence for the treatment of anemia in the neonatal population, including the use of red blood cell transfusions, erythropoietic stimulating agents, and iron supplementation.

Increasing Sodium Variability in the First 96 Hours after Birth is Associated with Adverse In-Hospital Outcomes of Preterm Newborns

Background

Neonatal intraventricular hemorrhage prevention bundles for preterm infants commonly defer daily weighing for the first 72 h, with reweighing occurring on day 4. Clinicians rely on maintaining stable sodium values as a proxy of fluid status to inform fluid management decisions over the first 96 h after birth. Yet, there exists a paucity of research evaluating whether serum sodium or osmolality are appropriate proxies for weight loss and whether increasing variability in sodium or osmolality during this early transitional period is associated with adverse in-hospital outcomes.

Objectives

To evaluate whether serum sodium or osmolality change in the first 96 h after birth was associated with percent weight change from birth weight, and to assess potential associations between serum sodium and osmolality variability with in-hospital outcomes.

Methods

This retrospective, cross-sectional study included neonates born at ≤30 gestational weeks or ≤1250 g. We evaluated associations between serum sodium coefficient of variation (CoV), osmolality CoV, and maximal weight loss percentage in the first 96 h after birth with in-hospital neonatal outcomes.

Results

Among 205 infants, serum sodium and osmolality were poorly correlated with percent weight change in individual 24-h increments (R2 = 0.01-0.14). For every 1% increase in sodium CoV, there was an associated 2-fold increased odds of surgical necrotizing enterocolitis and 2-fold increased odds of in-hospital mortality (odds ratio, 2.07; 95% CI: 1.02, 4.54; odds ratio, 1.95; 95% CI: 1.10, 3.64, respectively). Sodium CoV was more strongly associated with outcomes than absolute sodium maximal change.

Conclusions

In the first 96 h, serum sodium and osmolality are poor proxies for assessing percent weight change. Increasing variability of serum sodium is associated with later development of surgical necrotizing enterocolitis and all-cause in-hospital mortality. Prospective research is needed to evaluate whether reducing sodium variability in the first 96 h after birth, as assessed by CoV, improves newborn health outcomes.

Effectiveness of a care bundle for primary prevention of intraventricular hemorrhage in high-risk neonates: a Bayesian analysis

OBJECTIVE

To determine whether an intraventricular hemorrhage (IVH) prevention bundle featuring midline-elevated positioning reduced IVH among high-risk infants.

STUDY DESIGN

In a retrospective study design, we compared outcomes of infants <1250 grams birth weight or <30 weeks gestation before (N = 205) and after (N = 360) implementation of an IVH prevention bundle, using Bayesian and frequentist logistic regression to determine whether the intervention decreased any grade IVH.

RESULTS

In both the Bayesian and frequentist analyses, there was no difference in odds of any grade IVH before and after the implementation of the prevention bundle (OR 0.993; 95% Credible Interval 0.751-1.323 and OR 1.23; 95% Confidence Interval 0.818-1.864 respectively). Bias analyses suggested that these results were robust to bias from potential deaths attributable to IVH.

CONCLUSION

In this retrospective analysis, we found no evidence for a protective effect of an IVH prevention bundle on IVH incidence among high-risk neonates at a level IV NICU.

Neuroprotective therapies in the NICU in term infants: present and future

Outcomes of neonatal encephalopathy (NE) have improved since the widespread implementation of therapeutic hypothermia (TH) in high-resource settings. While TH for NE in term and near-term infants has proven beneficial, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. There is therefore a critical need to find additional pharmacological and non-pharmacological interventions that improve the outcomes for these children. There are many potential candidates; however, it is unclear whether these interventions have additional benefits when used with TH. Although primary and delayed (secondary) brain injury starting in the latent phase after HI are major contributors to neurodisability, the very late evolving effects of tertiary brain injury likely require different interventions targeting neurorestoration. Clinical trials of seizure management and neuroprotection bundles are needed, in addition to current trials combining erythropoietin, stem cells, and melatonin with TH. IMPACT: The widespread use of therapeutic hypothermia (TH) in the treatment of neonatal encephalopathy (NE) has reduced the associated morbidity and mortality. However, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. This review details the pathophysiology of NE along with the evidence for the use of TH and other beneficial neuroprotective strategies used in term infants. We also discuss treatment strategies undergoing evaluation at present as potential adjuvant treatments to TH in NE.

Postnatal maximal weight loss, fluid administration, and outcomes in extremely preterm newborns

OBJECTIVE

Evaluate maximal weight loss (MWL) and total fluid administration (TFA) association in first week after birth with outcomes among extremely preterm (EP) newborns.

STUDY DESIGN

We performed a retrospective analysis of the Preterm Erythropoietin Neuroprotection Trial evaluating first-week MWL, TFA, and association with in-hospital outcomes.

RESULTS

Among n = 883 included EP neonates, n = 842 survived ≥ 7 days and were included in outcome analyses. MWL between 5% to 15% was associated with decreased odds of necrotizing enterocolitis compared to MWL > 15% (OR 0.49, 95% CI 0.25-0.98). Average TFA > 150 mL/kg birthweight/day was associated with increased odds of necrotizing enterocolitis (OR 3.22, 95% CI 1.40-7.42) and patent ductus arteriosus requiring surgery (OR 2.14, 95% CI 1.10-4.15).

CONCLUSION

MWL between 5% to 15% is a potentially optimal window of MWL. Increasing average TFA in the first week is associated with adverse neonatal outcomes. Prospective studies evaluating MWL and TFA and relationship to outcomes in EP neonates are needed.

CLINICAL TRIAL REGISTRATION

This study is a secondary analysis of pre-existing data from the PENUT Trial Registration: NCT01378273, https://clinicaltrials.gov/ct2/show/NCT01378273 .

Prevalence and Risk Factors for Kidney Disease and Elevated BP in 2-Year-Old Children Born Extremely Premature

BACKGROUND AND OBJECTIVES

Extremely low gestational age neonates born <28 weeks gestation are at risk for chronic disease. We sought to describe the prevalence of kidney outcomes by gestational age and determine risk factors for their development.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Recombinant Erythropoietin for Protection of Infant Renal Disease (REPAIReD) study examined kidney outcomes of extremely low gestational age neonates enrolled in the Preterm Epo NeuroProtection Trial (PENUT) study. Kidney function, urine albumin, and BP were measured at 2-year (24±2 months) corrected gestational age. We compared outcomes across gestational age categories and evaluated associations between kidney-related outcomes and neonatal and maternal characteristics. The primary outcome was eGFR <90 ml/min per 1.73 m² (CKD); secondary outcomes were spot urine albumin-creatinine ratio ≥30 mg/g (albuminuria) and either systolic BP or diastolic BP >90th percentile for height, age, and sex.

RESULTS

A total of 832 survived to 2 years, and 565 (68%) had at least one outcome measured. Overall, 297 (53%) had one abnormal kidney outcome; 61 (18%) had an eGFR <90 ml/min per 1.73 m², 155 (36%) had albuminuria, 65 (22%) had elevated systolic BP, and 128 (44%) had elevated diastolic BP. Gestational age (odds ratio, 0.94; 95% confidence interval, 0.89 to 0.99), birth weight z-score (odds ratio, 0.92; 95% confidence interval, 0.85 to 0.98), and prenatal steroids (odds ratio, 1.23; 95% confidence interval, 1.08 to 1.39) were associated with an eGFR <90 ml/min per 1.73 m². An elevated systolic BP was associated with indomethacin use (odds ratio, 1.18; 95% confidence interval, 1.04 to 1.33) and Black race (odds ratio, 1.19; 95% confidence interval, 1.01 to 1.39); elevated diastolic BP was associated with male sex (odds ratio, 1.29; 95% confidence interval, 1.12 to 1.49), severe AKI (odds ratio, 1.24; 95% confidence interval, 1.04 to 1.48), and indomethacin use (odds ratio, 1.16; 95% confidence interval, 1.01 to 1.33).

CONCLUSIONS

Approximately 18% of extremely low gestational age neonates have CKD, 36% have albuminuria, 22% have an elevated systolic BP, and 44% have an elevated diastolic BP at 2 years of age. Gestational age, birthweight z-score, and prenatal steroids were associated with CKD. Male sex, Black race, indomethacin use, and severe AKI were associated with elevated BP.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2022_07_19_CJN15011121.mp3.

Trial of Erythropoietin for Hypoxic-Ischemic Encephalopathy in Newborns

BACKGROUND

Neonatal hypoxic-ischemic encephalopathy is an important cause of death as well as long-term disability in survivors. Erythropoietin has been hypothesized to have neuroprotective effects in infants with hypoxic-ischemic encephalopathy, but its effects on neurodevelopmental outcomes when given in conjunction with therapeutic hypothermia are unknown.

METHODS

In a multicenter, double-blind, randomized, placebo-controlled trial, we assigned 501 infants born at 36 weeks or more of gestation with moderate or severe hypoxic-ischemic encephalopathy to receive erythropoietin or placebo, in conjunction with standard therapeutic hypothermia. Erythropoietin (1000 U per kilogram of body weight) or saline placebo was administered intravenously within 26 hours after birth, as well as at 2, 3, 4, and 7 days of age. The primary outcome was death or neurodevelopmental impairment at 22 to 36 months of age. Neurodevelopmental impairment was defined as cerebral palsy, a Gross Motor Function Classification System level of at least 1 (on a scale of 0 [normal] to 5 [most impaired]), or a cognitive score of less than 90 (which corresponds to 0.67 SD below the mean, with higher scores indicating better performance) on the Bayley Scales of Infant and Toddler Development, third edition.

RESULTS

Of 500 infants in the modified intention-to-treat analysis, 257 received erythropoietin and 243 received placebo. The incidence of death or neurodevelopmental impairment was 52.5% in the erythropoietin group and 49.5% in the placebo group (relative risk, 1.03; 95% confidence interval [CI], 0.86 to 1.24; P = 0.74). The mean number of serious adverse events per child was higher in the erythropoietin group than in the placebo group (0.86 vs. 0.67; relative risk, 1.26; 95% CI, 1.01 to 1.57).

CONCLUSIONS

The administration of erythropoietin to newborns undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy did not result in a lower risk of death or neurodevelopmental impairment than placebo and was associated with a higher rate of serious adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT02811263.).

Gestational age, sex, and time affect urine biomarker concentrations in extremely low gestational age neonates

BACKGROUND

Our understanding of the normative concentrations of urine biomarkers in premature neonates is limited.

METHODS

We evaluated urine from 750 extremely low gestational age (GA) neonates without severe acute kidney injury (AKI) to determine how GA affects ten different urine biomarkers at birth and over the first 30 postnatal days. Then, we investigated if the urine biomarkers changed over time at 27, 30, and 34 weeks postmenstrual age (PMA). Next, we evaluated the impact of sex on urine biomarker concentrations at birth and over time. Finally, we evaluated if urine biomarkers were impacted by treatment with erythropoietin (Epo).

RESULTS

We found that all ten biomarker concentrations differ at birth by GA and that some urine biomarker concentrations increase, while others decrease over time. At 27 weeks PMA, 7/10 urine biomarkers differed by GA. By 30 weeks PMA, 5/10 differed, and by 34 weeks PMA, only osteopontin differed by GA. About half of the biomarker concentrations differed by sex, and 4/10 showed different rates of change over time between males vs. females. We found no differences in urine biomarkers by treatment group.

CONCLUSIONS

The temporal patterns, GA, and sex differences need to be considered in urine AKI biomarker analyses.

IMPACT

Urine biomarker concentrations differ by GA at birth. Some urine biomarkers increase, while others decrease, over the first 30 postnatal days. Most urine biomarkers differ by GA at 27 weeks PMA, but are similar by 34 weeks PMA. Some urine biomarkers vary by sex in premature neonates. Urine biomarkers did not differ between neonates randomized to placebo vs. Epo.

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.

Vitamin E Decreases Cytotoxicity and Mitigates Inflammatory and Oxidative Stress Responses in a Ferret Organotypic Brain Slice Model of Neonatal Hypoxia-Ischemia

The gyrencephalic ferret brain is an excellent model in which to study hypoxia-ischemia (HI), a significant contributor to neurological injury in neonates. Vitamin E, an essential fat-soluble antioxidant, reduces oxidative stress and inflammation in both animal models and neonates. The aim of this study was to assess the effects of Vitamin E after oxygen glucose deprivation (OGD) in an organotypic ferret brain slice model of neonatal HI. We hypothesized that Vitamin E would decrease cytotoxicity, inflammation, and oxidative stress in OGD-exposed brain slices. Term-equivalent ferrets were sacrificed at postnatal (P) day 21-23 and 300µM whole hemisphere brain slices were obtained. During a 24h rest period, slices were cultured in either non-treated control conditions or with Erastin, a promotor of oxidative stress. Slices were then exposed to 2h of OGD followed by Vitamin E (25-100 IU/kg), Erastin (10µM) or Ferrostatin (1µM), an inhibitor of ferroptosis. Relative cytotoxicity was determined using an LDH assay, cell death was quantified via nuclear propidium iodide (PI) staining, oxidative stress was quantified via cellular GSH (glutathione) levels and target genes responsive to oxidative stress and inflammation were evaluated by qRT-PCR. OGD increased cytotoxicity, which was significantly reduced by treatment with Vitamin E. Vitamin E also preserved GSH after OGD and decreased amplification of certain markers of oxidative stress (CHAC1, SLC7A11) and inflammation (TNF-alpha, IL-8). Vitamin E remained protective after pretreatment with Erastin and was more protective than Ferrostatin, presumably due to its added anti-inflammatory properties. Results from the ferret whole hemisphere OGD model support the premise that Vitamin E neuroprotection is mediated by restoring GSH and acutely decreasing inflammation and oxidative stress after neonatal HI brain injury.

Deaths in a Modern Cohort of Extremely Preterm Infants From the Preterm Erythropoietin Neuroprotection Trial

IMPORTANCE

Understanding why and how extremely preterm infants die is important for practitioners caring for these infants.

OBJECTIVE

To examine risk factors, causes, timing, and circumstances of death in a modern cohort of extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort review of infants enrolled in the Preterm Erythropoietin Neuroprotection Trial between December 13, 2013, and September 26, 2016, was conducted. A total of 941 infants born between 24 0/7 and 27 6/7 weeks of gestation enrolled at 19 US sites comprising 30 neonatal intensive care units were included. Data analysis was performed from October 16, 2020, to December 1, 2021.

MAIN OUTCOMES AND MEASURES

Risk factors, proximal causes, timing, and circumstances of in-hospital death.

RESULTS

Of the 941 enrolled infants, 108 died (11%) before hospital discharge: 38% (n = 41) at 24 weeks' gestation, 30% (n = 32) at 25 weeks' gestation, 19% (n = 20) at 26 weeks' gestation, and 14% (n = 15) at 27 weeks' gestation. An additional 9 infants (1%) died following hospital discharge. In descending order, the primary causes of death included respiratory distress or failure, pulmonary hemorrhage, necrotizing enterocolitis, catastrophic intracranial hemorrhage, sepsis, and sudden unexplained death. Fifty percent of deaths occurred within the first 10 days after birth. The risk of death decreased with day of life and postmenstrual age such that an infant born at 24 weeks' gestation who survived 14 days had the same risk of death as an infant born at 27 weeks' gestation: conditional proportional risk of death, 0.08 (95% CI, 0.03-0.13) vs 0.06 (95% CI, 0.01-0.11). Preterm labor was associated with a decreased hazard of death (hazard ratio [HR], 0.45; 95% CI, 0.31-0.66). Infant clinical factors associated with death included birth weight below the tenth percentile for gestational age (HR, 2.11; 95% CI, 1.38-3.22), Apgar score less than 5 at 5 minutes (HR, 2.19; 95% CI, 1.48-3.24), sick appearance at birth (HR, 2.49; 95% CI, 1.69-3.67), grade 2b-3 necrotizing enterocolitis (HR, 7.41; 95% CI, 5.14-10.7), pulmonary hemorrhage (HR, 10.0; 95% CI, 6.76-18.8), severe intracranial hemorrhage (HR, 4.60; 95% CI, 3.24-5.63), and severe sepsis (HR, 4.93; 95% CI, 3.67-7.21). Fifty-one percent of the infants received comfort care before death.

CONCLUSIONS AND RELEVANCE

In this cohort study, an association between mortality and gestational age at birth was noted; however, for each week that an infant survived, their risk of subsequent death approximated the risk observed in infants born 1 to 2 weeks later, suggesting the importance of an infant's postmenstrual age. This information may be useful to include in counseling of families regarding prognosis of survival.

Do Extremely Low Gestational Age Neonates Regulate Iron Absorption via Hepcidin?

OBJECTIVES

To evaluate whether extremely preterm infants regulate iron status via hepcidin.

STUDY DESIGN

In this retrospective analysis of infants from the Preterm Epo Neuroprotection (PENUT) Trial, urine hepcidin (Uhep) normalized to creatinine (Uhep/UCr) was evaluated among infants randomized to erythropoietin (Epo) or placebo.

RESULTS

The correlation (r) between Uhep/UCr and serum markers of iron status (ferritin and zinc protoporphyrin-to-heme ratio [ZnPP/H]) and iron dose was assessed. A total of 243 urine samples from 76 infants born at 24-27^6/7 weeks gestation were analyzed. The median Uhep/UCr concentration was 0.3, 1.3, 0.4, and 0.1 ng/mg at baseline, 2 weeks, 4 weeks, and 12 weeks, respectively, in placebo-treated infants. The median Uhep/UCr value in Epo-treated infants were not significantly different, with the exception of the value at the 2-week time point (median Uhep/UCr, 0.1 ng/mg; P < .001). A significant association was seen between Uhep/UCr and ferritin at 2 weeks (r = 0.63; P < .001) and at 4 weeks (r = 0.41; P = .01) and between Uhep/UCr and ZnPP/H at 2 weeks (r = -0.49; P = .002).

CONCLUSIONS

Uhep/UCr values correlate with serum iron markers. Uhep/UCr values vary over time and are affected by treatment with Epo, suggesting that extremely preterm neonates can regulate hepcidin and therefore their iron status. Uhep is suppressed in extremely preterm neonates, particularly those treated with Epo.

Parental Enrollment Decision-Making for a Neonatal Clinical Trial

OBJECTIVE

To describe the parental experience of recruitment and assess differences between parents who participated and those who declined to enroll in a neonatal clinical trial.

STUDY DESIGN

This was a survey conducted at 12 US neonatal intensive care units of parents of infants who enrolled in the High-dose Erythropoietin for Asphyxia and encephaLopathy (HEAL) trial or who were eligible but declined enrollment. Questions assessed 6 factors of the parental experience of recruitment: (1) interactions with research staff; (2) the consent experience; (3) perceptions of the study; (4) decisional conflict; (5) reasons for/against participation; and (6) timing of making the enrollment decision.

RESULTS

In total, 269 of 387 eligible parents, including 183 of 242 (75.6%) of those who enrolled their children in HEAL and 86 of 145 (59.3%) parents who declined to enroll their children in HEAL, were included in analysis. Parents who declined to enroll more preferred to be approached by clinical team members rather than by research team members (72.9% vs 49.2%, P = .005). Enrolled parents more frequently reported positive initial impressions (54.9% vs 10.5%, P < .001). Many parents in both groups made their decision early in the recruitment process. Considerations of reasons for/against participation differed by enrollment status.

CONCLUSIONS

Understanding how parents experience recruitment, and how this differs by enrollment status, may help researchers improve recruitment processes for families and increase enrollment. The parental experience of recruitment varied by enrollment status. These findings can guide future work aiming to inform optimal recruitment strategies for neonatal clinical trials.

Association between Term Equivalent Brain Magnetic Resonance Imaging and 2-Year Outcomes in Extremely Preterm Infants: A Report from the Preterm Erythropoietin Neuroprotection Trial Cohort

OBJECTIVES

To compare the term equivalent brain magnetic resonance imaging (MRI) findings between erythropoietin (Epo) treated and placebo control groups in infants 24^0/7-27^6/7 weeks of gestational age and to assess the associations between MRI findings and neurodevelopmental outcomes at 2 years corrected age.

STUDY DESIGN

The association between brain abnormality scores and Bayley Scales of Infant Development, Third Edition at 2 years corrected age was explored in a subset of infants enrolled in the Preterm Erythropoietin Neuroprotection Trial. Potential risk factors for neurodevelopmental outcomes such as treatment assignment, recruitment site, gestational age, inpatient complications, and treatments were examined using generalized estimating equation models.

RESULTS

One hundred ten infants were assigned to Epo and 110 to placebo groups. 27% of MRI scans were rated as normal, and 60%, 10%, and 2% were rated as having mild, moderate, or severe abnormality. Brain abnormality scores did not significantly differ between the treatment groups. Factors that increased the risk of higher brain injury scores included intubation; bronchopulmonary dysplasia; retinopathy of prematurity; opioid, benzodiazepine, or antibiotic treatment >7 days; and periventricular leukomalacia or severe intraventricular hemorrhage diagnosed on cranial ultrasound. Increased global brain abnormality and white matter injury scores at term equivalent were associated with reductions in cognitive, motor, and language abilities at 2 years of corrected age.

CONCLUSIONS

Evidence of brain injury on brain MRIs obtained at term equivalent correlated with adverse neurodevelopmental outcomes as assessed by the Bayley Scales of Infant and Toddler Development, Third Edition at 2 years corrected age. Early Epo treatment had no effect on the MRI brain injury scores compared with the placebo group.

A ferret brain slice model of oxygen–glucose deprivation captures regional responses to perinatal injury and treatment associated with specific microglial phenotypes

Organotypic brain slice models are an ideal technological platform to investigate therapeutic options for hypoxic‐ischemic (HI) brain injury, a leading cause of morbidity and mortality in neonates. The brain exhibits regional differences in the response to HI injury in vivo. This can be modeled using organotypic brain slices, which maintain three‐dimensional regional structures and reflect the regional differences in injury response. Here, we developed an organotypic whole hemisphere (OWH) slice culture model of HI injury using the gyrencephalic ferret brain at a developmental stage equivalent to a full‐term human infant in order to better probe region‐specific cellular responses to injury. Each slice encompassed the cortex, corpus callosum, subcortical white matter, hippocampus, basal ganglia, and thalamus. Regional responses to treatment with either erythropoietin (Epo) or the ketone body acetoacetate (AcAc) were highly heterogenous. While both treatments suppressed global injury responses and oxidative stress, significant neuroprotection was only seen in a subset of regions, with others displaying no response or potential exacerbation of injury. Similar regional heterogeneity was seen in the morphology and response of microglia to injury and treatment, which mirrored those seen after injury in vivo. Within each region, machine‐learning‐based classification of microglia morphological shifts in response to injury predicted the neuroprotective response to each therapy, with different morphologies associated with different treatment responses. This suggests that the ferret OWH slice culture model provides a platform for examining regional responses to injury in the gyrencephalic brain, as well as for screening combinations of therapeutics to provide global neuroprotection after injury.