Social Determinants of Health and Redirection of Care for Infants Born Extremely Preterm

Importance

Redirection of care refers to withdrawal, withholding, or limiting escalation of treatment. Whether maternal social determinants of health are associated with redirection of care discussions merits understanding.

Objective

To examine associations between maternal social determinants of health and redirection of care discussions for infants born extremely preterm.

Design, Setting, and Participants

This is a retrospective analysis of a prospective cohort of infants born at less than 29 weeks' gestation between April 2011 and December 2020 at 19 National Institute of Child Health and Human Development Neonatal Research Network centers in the US. Follow-up occurred between January 2013 and October 2023. Included infants received active treatment at birth and had mothers who identified as Black or White. Race was limited to Black and White based on service disparities between these groups and limited sample size for other races. Maternal social determinant of health exposures were education level (high school nongraduate or graduate), insurance type (public/none or private), race (Black or White), and ethnicity (Hispanic or non-Hispanic).

Main Outcomes and Measures

The primary outcome was documented discussion about redirection of infant care. Secondary outcomes included subsequent redirection of care occurrence and, for those born at less than 27 weeks' gestation, death and neurodevelopmental impairment at 22 to 26 months' corrected age.

Results

Of the 15 629 infants (mean [SD] gestational age, 26 [2] weeks; 7961 [51%] male) from 13 643 mothers, 2324 (15%) had documented redirection of care discussions. In unadjusted comparisons, there was no significant difference in the percentage of infants with redirection of care discussions by race (Black, 1004/6793 [15%]; White, 1320/8836 [15%]) or ethnicity (Hispanic, 291/2105 [14%]; non-Hispanic, 2020/13 408 [15%]). However, after controlling for maternal and neonatal factors, infants whose mothers identified as Black or as Hispanic were less likely to have documented redirection of care discussions than infants whose mothers identified as White (Black vs White adjusted odds ratio [aOR], 0.84; 95% CI, 0.75-0.96) or as non-Hispanic (Hispanic vs non-Hispanic aOR, 0.72; 95% CI, 0.60-0.87). Redirection of care discussion occurrence did not differ by maternal education level or insurance type.

Conclusions and Relevance

For infants born extremely preterm, redirection of care discussions occurred less often for Black and Hispanic infants than for White and non-Hispanic infants. It is important to explore the possible reasons underlying these differences.

Secular Trends in Patent Ductus Arteriosus Management in Infants Born Preterm in the National Institute of Child Health and Human Development Neonatal Research Network

We evaluated changes in patent ductus arteriosus (PDA) diagnosis and treatment from 2012 through 2021 in a network of US academic hospitals. PDA treatment decreased among infants born at 26-28 weeks but not among infants born at 22-25 weeks. Rates of indomethacin use and PDA ligation decreased while acetaminophen use and transcatheter PDA closure increased.

Association of maternal pre-pregnancy or first trimester body mass index with neurodevelopmental impairment or death in extremely low gestational age neonates

OBJECTIVE

To compare the rates of death or survival with severe neurodevelopmental impairment (sNDI) at 2 years among extremely preterm infants in relation to pre-pregnancy or first-trimester maternal body mass index (BMI).

METHODS

This retrospective cohort study included extremely preterm infants (gestational age 220/7-266/7 weeks). The study was conducted at National Institute of Child Health and Human Development Neonatal Research Network sites. The primary outcome was death or sNDI at 2 years.

RESULTS

Data on the primary outcome were available for 1208 children. Death or sNDI was not different among the three groups: 54.9% in normal, 56.1% in overweight, and 53.4% in obese group (p = 0.39). There was no significant difference in mortality, sNDI, moderate/severe cerebral palsy, Bayley Scales of Infant Development (BSID)-III cognitive composite score <70, BSID-III language composite score <70 in adjusted models.

CONCLUSION

Neurodevelopmental outcome was not significantly associated with maternal pre-pregnancy BMI among extreme preterm infants.

Social distancing and extremely preterm births in the initial COVID-19 pandemic period

HYPOTHESIS

Increased social distancing was associated with a lower incidence of extremely preterm live births (EPLB) during the initial COVID-19 pandemic period.

STUDY DESIGN

Prospective study at the NICHD Neonatal Research Network sites comparing EPLB (220/7-286/7 weeks) and extremely preterm intrapartum stillbirths (EPIS) rates during the pandemic period (March-July, weeks 9-30 of 2020) with the reference period (same weeks in 2018 and 2019), correlating with state-specific social distancing index (SDI).

RESULTS

EPLB and EPIS percentages did not significantly decrease (1.58-1.45%, p = 0.07, and 0.08-0.06%, p = 0.14, respectively). SDI was not significantly correlated with percent change of EPLB (CC = 0.29, 95% CI = -0.12, 0.71) or EPIS (CC = -0.23, 95% CI = -0.65, 0.18). Percent change in mean gestational age was positively correlated with SDI (CC = 0.49, 95% CI = 0.07, 0.91).

CONCLUSIONS

Increased social distancing was not associated with change in incidence of EPLB but was associated with a higher gestational age of extremely preterm births.

CLINICALTRIALS

GOV ID

Generic Database: NCT00063063.

Neurodevelopmental Outcomes of Extremely Preterm Infants Fed Donor Milk or Preterm Infant Formula: A Randomized Clinical Trial

Importance

Maternal milk feeding of extremely preterm infants during the birth hospitalization has been associated with better neurodevelopmental outcomes compared with preterm formula. For infants receiving no or minimal maternal milk, it is unknown whether donor human milk conveys similar neurodevelopmental advantages vs preterm formula.

Objective

To determine if nutrient-fortified, pasteurized donor human milk improves neurodevelopmental outcomes at 22 to 26 months' corrected age compared with preterm infant formula among extremely preterm infants who received minimal maternal milk.

Design, Setting, and Participants

Double-blind, randomized clinical trial conducted at 15 US academic medical centers within the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Infants younger than 29 weeks 0 days' gestation or with a birth weight of less than 1000 g were enrolled between September 2012 and March 2019.

Intervention

Preterm formula or donor human milk feeding from randomization to 120 days of age, death, or hospital discharge.

Main Outcomes and Measures

The primary outcome was the Bayley Scales of Infant and Toddler Development (BSID) cognitive score measured at 22 to 26 months' corrected age; a score of 54 (score range, 54-155; a score of ≥85 indicates no neurodevelopmental delay) was assigned to infants who died between randomization and 22 to 26 months' corrected age. The 24 secondary outcomes included BSID language and motor scores, in-hospital growth, necrotizing enterocolitis, and death.

Results

Of 1965 eligible infants, 483 were randomized (239 in the donor milk group and 244 in the preterm formula group); the median gestational age was 26 weeks (IQR, 25-27 weeks), the median birth weight was 840 g (IQR, 676-986 g), and 52% were female. The birthing parent's race was self-reported as Black for 52% (247/478), White for 43% (206/478), and other for 5% (25/478). There were 54 infants who died prior to follow-up; 88% (376/429) of survivors were assessed at 22 to 26 months' corrected age. The adjusted mean BSID cognitive score was 80.7 (SD, 17.4) for the donor milk group vs 81.1 (SD, 16.7) for the preterm formula group (adjusted mean difference, -0.77 [95% CI, -3.93 to 2.39], which was not significant); the adjusted mean BSID language and motor scores also did not differ. Mortality (death prior to follow-up) was 13% (29/231) in the donor milk group vs 11% (25/233) in the preterm formula group (adjusted risk difference, -1% [95% CI, -4% to 2%]). Necrotizing enterocolitis occurred in 4.2% of infants (10/239) in the donor milk group vs 9.0% of infants (22/244) in the preterm formula group (adjusted risk difference, -5% [95% CI, -9% to -2%]). Weight gain was slower in the donor milk group (22.3 g/kg/d [95% CI, 21.3 to 23.3 g/kg/d]) compared with the preterm formula group (24.6 g/kg/d [95% CI, 23.6 to 25.6 g/kg/d]).

Conclusions and Relevance

Among extremely preterm neonates fed minimal maternal milk, neurodevelopmental outcomes at 22 to 26 months' corrected age did not differ between infants fed donor milk or preterm formula.

Trial Registration

ClinicalTrials.gov Identifier: NCT01534481.

Serum ferritin values in neonates <29 weeks' gestation are highly variable and do not correlate with reticulocyte hemoglobin content

OBJECTIVES

To compare serum ferritin and RET-He values among extremely low gestational age neonates ELGANs with other markers of iron-deficient erythropoiesis.

STUDY DESIGN

This is a secondary analysis of the NICHD Darbepoetin Trial. Study data from placebo recipients who had a serum ferritin, a RET-He, and a mean corpuscular volume (MCV) measurement within a 24-hour period were analyzed for correlation.

RESULTS

Mixed linear regression models showed no association between ferritin and RET-He at both early (β = 0.0016, p = 0.40) and late (β = -0.0001, p = 0.96) time points. Positive associations were observed between RET-He and MCV at baseline, early, and late time points (p < 0.01, =0.01, <0.001, respectively), while ferritin was not associated with MCV at any time point.

CONCLUSIONS

Our study shows that RET-He is better correlated with MCV as a marker of iron-limited erythropoiesis than ferritin. The results suggest that ferritin is limited as a marker of iron sufficiency in premature infants.

STUDY IDENTIFICATION

FDA IND Number 100138; ClinicalTrials.gov number NCT03169881; NRN ID number NICHD-NRN-0058 (Darbe).

Relationships between retinopathy of prematurity without ophthalmologic intervention and neurodevelopment and vision at 2 years

BACKGROUND

Severe retinopathy of prematurity (ROP) is associated with adverse outcomes. Relationships between milder ROP and outcomes have not been defined. We hypothesized that children with ROP stage ≤3 who did not receive ophthalmologic intervention would have worse motor, cognitive, and language skills and more vision abnormalities than children without ROP.

METHODS

This was a secondary analysis of a randomized trial evaluating the effects of myo-inositol on ROP in the NICHD Neonatal Research Network. Primary outcomes were Bayley Scales of Infant Development composite scores; secondary outcomes included behavioral difficulties and ophthalmologic measures. Outcomes were compared using adjusted linear or modified Poisson models.

RESULTS

Of 506 children, 173 (34%) had no ROP, 262 (52%) had ROP stage ≤3 without intervention, and 71 (14%) had ROP with intervention. There was no difference in motor, cognitive, or language scores between children with ROP stage ≤3 without intervention and children without ROP. Children with ROP stage ≤3 without intervention had a higher rate of strabismus compared to children without ROP (p = 0.040).

CONCLUSION

Children with ROP stage ≤3 without intervention did not have adverse neurodevelopmental outcomes at 2 years' corrected age compared to children without ROP but did have an increased incidence of strabismus.

IMPACT

This study addresses a gap in the literature regarding the relationship between milder forms of retinopathy of prematurity (ROP) that regress without intervention and neurodevelopment and vision outcomes. Children with a history of ROP stage ≤3 without intervention have similar neurodevelopmental outcomes at 2 years' corrected age as children born extremely preterm without a history of ROP and better outcomes than children with a history of ROP with ophthalmologic intervention. Counseling about likely neurodevelopment and vision outcomes for children born extremely preterm with a history of ROP may be tailored based on the severity of ROP.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov ID: Inositol to Reduce Retinopathy of Prematurity Trial: NCT01954082.

Use of term reference infants in assessing the developmental outcome of extremely preterm infants: lessons learned in a multicenter study

OBJECTIVE

Extremely preterm (EP) impairment rates are likely underestimated using the Bayley III norm-based thresholds scores and may be better assessed relative to concurrent healthy term reference (TR) infants born in the same hospital.

STUDY DESIGN

Blinded, certified examiners in the Neonatal Research Network (NRN) evaluated EP survivors and a sample of healthy TR infants recruited near the 2-year assessment age.

RESULTS

We assessed 1452 EP infants and 183 TR infants. TR-based thresholds showed higher overall EP impairment than Bayley norm-based thresholds (O.R. = 1.86; [95% CI 1.56-2.23], especially for severe impairment (36% vs. 24%; p ≤ 0.001). Difficulty recruiting TR patients at 2 years extended the study by 14 months and affected their demographics.

CONCLUSION

Impairment rates among EP infants appear to be substantially underestimated from Bayley III norms. These rates may be best assessed by comparison with healthy term infants followed with minimal attrition from birth in the same centers.

CLINICALTRIALS

GOV ID

Term Reference (under the Generic Database Study): NCT00063063.

Tissue Oxygenation Changes After Transfusion and Outcomes in Preterm Infants: A Secondary Near-Infrared Spectroscopy Study of the Transfusion of Prematures Randomized Clinical Trial (TOP NIRS)

Importance

Preterm infants with varying degrees of anemia have different tissue oxygen saturation responses to red blood cell (RBC) transfusion, and low cerebral saturation may be associated with adverse outcomes.

Objective

To determine whether RBC transfusion in preterm infants is associated with increases in cerebral and mesenteric tissue saturation (Csat and Msat, respectively) or decreases in cerebral and mesenteric fractional tissue oxygen extraction (cFTOE and mFTOE, respectively) and whether associations vary based on degree of anemia, and to investigate the association of Csat with death or neurodevelopmental impairment (NDI) at 22 to 26 months corrected age.

Design, Setting, and Participants

This was a prospective observational secondary study conducted among a subset of infants between August 2015 and April 2017 in the Transfusion of Prematures (TOP) multicenter randomized clinical trial at 16 neonatal intensive care units of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Preterm neonates with gestational age 22 to 28 weeks and birth weight 1000 g or less were randomized to higher or lower hemoglobin thresholds for transfusion. Data were analyzed between October 2020 and May 2022.

Interventions

Near-infrared spectroscopy monitoring of Csat and Msat.

Main Outcomes and Measures

Primary outcomes were changes in Csat, Msat, cFTOE, and mFTOE after transfusion between hemoglobin threshold groups, adjusting for age at transfusion, gestational age, birth weight stratum, and center. Secondary outcome at 22 to 26 months was death or NDI defined as cognitive delay (Bayley Scales of Infant and Toddler Development-III score <85), cerebral palsy with Gross Motor Function Classification System level II or greater, or severe vision or hearing impairment.

Results

A total of 179 infants (45 [44.6%] male) with mean (SD) gestational age 25.9 (1.5) weeks were enrolled, and valid data were captured from 101 infants during 237 transfusion events. Transfusion was associated with a significant increase in mean Csat of 4.8% (95% CI, 2.7%-6.9%) in the lower-hemoglobin threshold group compared to 2.7% (95% CI, 1.2%-4.2%) in the higher-hemoglobin threshold group, while mean Msat increased 6.7% (95% CI, 2.4%-11.0%) vs 5.6% (95% CI, 2.7%-8.5%). Mean cFTOE and mFTOE decreased in both groups to a similar extent. There was no significant change in peripheral oxygen saturation (SpO2) in either group (0.2% vs -0.2%). NDI or death occurred in 36 infants (37%). Number of transfusions with mean pretransfusion Csat less than 50% was associated with NDI or death (odds ratio, 2.41; 95% CI, 1.08-5.41; P = .03).

Conclusions and Relevance

In this secondary study of the TOP randomized clinical trial, Csat and Msat were increased after transfusion despite no change in SpO2. Lower pretransfusion Csat may be associated with adverse outcomes, supporting further investigation of targeted tissue saturation monitoring in preterm infants with anemia.

Trial Registration

ClinicalTrials.gov Identifier: NCT01702805.

Early-Life Outcomes in Relation to Social Determinants of Health for Children Born Extremely Preterm

OBJECTIVE

To characterize the relationships between social determinants of health (SDOH) and outcomes for children born extremely preterm.

STUDY DESIGN

This is a cohort study of infants born at 22-26 weeks of gestation in National Institute of Child Health and Human Development Neonatal Research Network centers (2006-2017) who survived to discharge. Infants were classified by 3 maternal SDOH: education, insurance, and race. Outcomes included postmenstrual age (PMA) at discharge, readmission, neurodevelopmental impairment (NDI), and death postdischarge. Regression analyses adjusted for center, perinatal characteristics, neonatal morbidity, ethnicity, and 2 SDOH (eg, group comparisons by education adjusted for insurance and race).

RESULTS

Of 7438 children, 5442 (73%) had at least 1 risk-associated SDOH. PMA at discharge was older (adjusted mean difference 0.37 weeks, 95% CL 0.06, 0.68) and readmission more likely (aOR 1.27, 95% CL 1.12, 1.43) for infants whose mothers had public/no insurance vs private. Neither PMA at discharge nor readmission varied by education or race. NDI was twice as likely (aOR 2.36, 95% CL 1.86, 3.00) and death 5 times as likely (aOR 5.22, 95% CL 2.54, 10.73) for infants with 3 risk-associated SDOH compared with those with none.

CONCLUSIONS

Children born to mothers with public/no insurance were older at discharge and more likely to be readmitted than those born to privately insured mothers. NDI and death postdischarge were more common among children exposed to multiple risk-associated SDOH at birth compared with those not exposed. Addressing disparities due to maternal education, insurance coverage, and systemic racism are potential intervention targets to improve outcomes for children born preterm.

Red Blood Cell Transfusion Thresholds for Anemia of Prematurity

Anemia of prematurity affects the majority of preterm infants, particularly extremely low birthweight infants. Anemia of prematurity arises from both innate and iatrogenic causes and results in more than 80% of extremely preterm infants receiving red blood cell transfusions during the first month after birth. Multiple randomized controlled trials were conducted to evaluate the effect of using lower versus higher transfusion thresholds based on hemoglobin levels. These trials showed no difference in the primary outcome of neurodevelopmental impairment at 2 years of age between lower and higher thresholds. However, some uncertainties about transfusion thresholds remain. This review elaborates the following: 1) the etiology, prevention, and treatment of anemia of prematurity with a focus on red blood cell transfusions, 2) the history of randomized controlled trials on the treatment of anemia of prematurity, and 3) limitations of the evidence and remaining questions about thresholds for red blood cell transfusions in preterm infants.

Model for severe intracranial hemorrhage and role of early indomethacin in extreme preterm infants

BACKGROUND

To develop a model for prediction of severe intracranial hemorrhage (ICH) or death based on variables from the first 12 h of age and to compare mortality and morbidities with and without exposure to early indomethacin.

METHODS

This retrospective cohort study included extreme preterm (220/7-266/7 weeks) infants born at National Institute of Child Health and Human Development Neonatal Research Network sites. Primary outcome was a composite of severe ICH and/or death.

RESULTS

Of 4624 infants, 1827 received early indomethacin. Lower gestation, lack of antenatal steroids exposure, lower 1-min Apgar, male sex, and receipt of epinephrine were associated with severe ICH or death. Early indomethacin was associated with a lower risk of patent ductus arteriosus, bronchopulmonary dysplasia, and higher risk of spontaneous intestinal perforation.

CONCLUSIONS

A model for early prediction of severe ICH/death was developed and validated. Early indomethacin was associated with a lower risk of patent ductus arteriosus and bronchopulmonary dysplasia and a higher risk of spontaneous intestinal perforation.

CLINICAL TRIAL REGISTRATION

Not applicable.

IMPACT

Modern data on severe ICH and neonatal morbidities in relation to prophylactic indomethacin are scarce in the published literature. Prophylactic indomethacin was associated with a lower risk of patent ductus arteriosus and bronchopulmonary dysplasia and a higher risk of intestinal perforation. A risk estimator for severe intracranial hemorrhage/death was developed in a large cohort of extremely preterm infants. The risk estimator developed based on a large cohort of patients provides an estimate of severe intracranial bleeding for an individual infant.

Incidence of and Neurodevelopmental Outcomes After Late-Onset Meningitis Among Children Born Extremely Preterm

Importance

Late-onset meningitis (LOM) has been associated with adverse neurodevelopmental outcomes in children born extremely preterm.

Objective

To report the incidence of LOM during birth hospitalization and neurodevelopmental outcomes at 18 to 26 months' corrected age.

Design, Setting, and Participants

This cohort study is a secondary analysis of a multicenter prospective cohort of children born at 22 to 26 weeks' gestation between 2003 and 2017 with follow-up from 2004 to 2021. The study was conducted at 25 Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network centers.

Exposures

Culture-confirmed LOM.

Main Outcomes and Measures

Incidence and microbiology of LOM (2003-2017); lumbar puncture (LP) performance in late-onset sepsis (LOS) evaluations (2011-2017); composite outcome of death or neurodevelopmental impairment (NDI; 2004-2021).

Results

Among 13 372 infants (median [IQR] gestational age, 25.4 [24.4-26.1] weeks; 6864 [51%] boys), LOM was diagnosed in 167 (1%); LOS without LOM in 4564 (34%); and neither LOS nor LOM in 8641 (65%). The observed incidence of LOM decreased from 2% (95% CI, 1%-3%) in 2003 to 0.4% (95% CI, 0.7%-1.0%) in 2017 (P < .001). LP performance in LOS evaluations decreased from 36% (95% CI, 33%-40%) in 2011 to 24% (95% CI, 21%-27%) in 2017 (P < .001). Among infants with culture-confirmed LOS, LP performance decreased from 58% (95% CI, 51%-65%) to 45% (95% CI, 38%-51%; P = .008). LP performance varied by center among all LOS evaluations (10%-59%, P < .001) and among those with culture-confirmed LOS (23%-79%, P < .001). LOM occurred in the absence of concurrent LOS in 27 of 167 cases (16%). The most common LOM isolates were coagulase-negative Staphylococcus (98 [59%]), Candida albicans (38 [23%]), and Escherichia coli (27 [16%]). Death or NDI occurred in 22 of 46 children (48%) with LOM due to coagulase-negative Staphylococcus, 43 of 67 (64%) due to all other bacterial pathogens, and 26 of 33 (79%) due to fungal pathogens. The adjusted relative risk of death or NDI was increased among children with LOM (aOR, 1.53; 95% CI, 1.04-2.25) and among those with LOS without LOM (aOR, 1.41; 95% CI, 1.29-1.54) compared with children with neither infection.

Conclusions and Relevance

In this cohort study, LP was performed with decreasing frequency, and the observed incidence of LOM also decreased. Both LOM and LOS were associated with increased risk of death or NDI; risk varied by LOM pathogen. The full association of LOM with outcomes of children born extremely preterm may be underestimated by current diagnostic practices.

Outcome prediction in newborn infants: Past, present, and future

The perinatal and neonatal periods are the periods of considerable organ development and maturation. Perinatal and neonatal illnesses can result in mortality and morbidities that burden families and the healthcare system. Outcome prediction is essential for informing perinatal and intensive care management, prognosis, and post-discharge interventions. The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) research databases include hospital and neurodevelopment follow-up outcomes of infants with various underlying diseases and conditions receiving intensive care, providing a unique opportunity to assess outcome risk prediction. The NRN has developed outcome risk prediction tools for use in infants with various diseases and conditions that allow data-driven, transparent discussions to inform family-focused communications and clinical management. This review presents the published neonatal outcome risk prediction research from the NRN, their present clinical utility, and possible future directions for advanced individualized risk prediction.

Contributions of the NICHD neonatal research network's generic database to documenting and advancing the outcomes of extremely preterm infants

The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) maintains a database of extremely preterm infants known as the Generic Database (GDB). Begun in 1987, this database now includes more than 91,000 infants, most of whom are extremely preterm (<29 weeks gestation). The GDB has been the backbone of the NRN, providing high quality, prospectively collected data to study the changing epidemiology of extreme prematurity and its outcomes over time. In addition, GDB data have been used to generate hypotheses for prospective studies and to develop new clinical trials by providing information about the numbers and characteristics of available subjects and the expected event rates for conditions and complications to be studied. Since its inception, the GDB has been the basis of more than 200 publications in peer-reviewed journals, many of which have had a significant impact on the field of neonatology.

Group B Streptococcus Infection in Extremely Preterm Neonates and Neurodevelopmental Outcomes at 2 Years

BACKGROUND

This study was performed to determine the incidence of group B Streptococcus (GBS) disease among extremely preterm infants and assess to risk of death or neurodevelopmental impairment (NDI) at a corrected age of 18-26 months.

METHODS

In this observational cohort study of infants enrolled in a multicenter registry, the incidence of GBS disease was assessed in infants born in 1998-2016 at 22-28 weeks' gestation and surviving for >12 hours. The composite outcome, death or NDI, was assessed in infants born in 1998-2014 at 22-26 weeks' gestation. Infection was defined as GBS isolation in blood or cerebrospinal fluid culture at ≤72 hours (early-onset disease [EOD]) or >72 hours (late-onset disease [LOD]) after birth. Using Poisson regression models, the outcome was compared in infants with GBS disease, infants infected with other pathogens, and uninfected infants.

RESULTS

The incidence of GBS EOD (2.70/1000 births [95% confidence interval (CI), 2.15-3.36]) and LOD (8.47/1000 infants [7.45-9.59]) did not change significantly over time. The adjusted relative risk of death/NDI was higher among infants with GBS EOD than in those with other infections (adjusted relative risk, 1.22 [95% CI, 1.02-1.45]) and uninfected infants (1.44 [1.23-1.69]). Risk of death/NDI did not differ between infants with GBS LOD and comparator groups. GBS LOD occurred at a significantly later age than non-GBS late-onset infection. Among infants surviving >30 days, the risk of death was higher with GBS LOD (adjusted relative risk, 1.90 [95% CI, 1.36-2.67]), compared with uninfected infants.

CONCLUSIONS

In a cohort of extremely preterm infants, the incidence of GBS disease did not change during the study period. The increased risk of death or NDI with GBS EOD, and of death among some infants with GBS LOD, supports the need for novel preventive strategies for disease reduction.

CLINICAL TRIALS REGISTRATION

NCT00063063.

Early brain and abdominal oxygenation in extremely low birth weight infants

BACKGROUND

Extremely low birth weight (ELBW) infants are at risk for end-organ hypoxia and ischemia. Regional tissue oxygenation of the brain and gut as monitored with near-infrared spectroscopy (NIRS) may change with postnatal age, but normal ranges are not well defined.

METHODS

A prospective study of ELBW preterm infants utilized NIRS monitoring to assess changes in cerebral and mesenteric saturation (Csat and Msat) over the first week after birth. This secondary study of a multicenter trial comparing hemoglobin transfusion thresholds assessed cerebral and mesenteric fractional tissue oxygen extraction (cFTOE and mFTOE) and relationships with perinatal variables.

RESULTS

In 124 infants, both Csat and Msat declined over the first week, with a corresponding increase in oxygen extraction. With lower gestational age, lower birth weight, and 5-min Apgar score ≤5, there was a greater increase in oxygen extraction in the brain compared to the gut. Infants managed with a lower hemoglobin transfusion threshold receiving ≥2 transfusions in the first week had the lowest Csat and highest cFTOE (p < 0.001).

CONCLUSION

Brain oxygen extraction preferentially increased in more immature and anemic preterm infants. NIRS monitoring may enhance understanding of cerebral and mesenteric oxygenation patterns and inform future protective strategies in the preterm ELBW population.

IMPACT

Simultaneous monitoring of cerebral and mesenteric tissue saturation demonstrates the balance of oxygenation between preterm brain and gut and may inform protective strategies. Over the first week, oxygen saturation of the brain and gut declines as oxygen extraction increases. A low hemoglobin transfusion threshold is associated with lower cerebral saturation and higher cerebral oxygen extraction compared to a high hemoglobin transfusion threshold, although this did not translate into clinically relevant differences in the TOP trial primary outcome. Greater oxygen extraction by the brain compared to the gut occurs with lower gestational age, lower birth weight, and 5-min Apgar score ≤5.

Association of Antenatal Steroid Exposure at 21 to 22 Weeks of Gestation With Neonatal Survival and Survival Without Morbidities

Importance

The provision of antenatal corticosteroids to pregnant patients at gestational age (GA) 22 6/7 weeks or less remains controversial and lacks support from randomized clinical trials.

Objective

To compare rates of survival and survival without major morbidities among infants born at GA 22 0/7 to 23 6/7 weeks after exposure to antenatal steroids at 22 6/7 weeks' gestation or less vs no exposure to antenatal steroids.

Design, Setting, and Participants

This cohort study enrolled infants born at GA 22 0/7 to 23 6/7 weeks between January 1, 2016, and December 31, 2019, at centers in the National Institute of Child Health and Human Development Neonatal Research Network. Infants who did not receive intensive care and infants with antenatal steroid exposure after GA 22 6/7 weeks were excluded.

Exposure

Infants were classified as having no, partial, or complete exposure to antenatal steroids.

Main Outcomes and Measures

The primary outcome was survival to discharge. The main secondary outcome was survival without major neonatal morbidity. The associations of differential exposures to antenatal steroids with outcomes were evaluated using logistic regression, adjusting for GA, sex, race, maternal education, small for GA status, mode of delivery, multiple birth, prolonged rupture of membranes, year of birth, and Neonatal Research Network center.

Results

A total of 431 infants (mean [SD] GA, 22.6 [0.5] weeks; 232 [53.8%] boys) were included, with 110 infants (25.5%) receiving no antenatal steroids, 80 infants (18.6%) receiving partial antenatal steroids, and 241 infants (55.9%) receiving complete antenatal steroids. Seventeen infants were exposed to antenatal steroids at GA 21 weeks. Among infants exposed to complete antenatal steroids, 130 (53.9%) survived to discharge, compared with 30 infants (37.5%) with partial antenatal steroid exposure and 239 infants (35.5%) with no antenatal steroids. Infants born after complete antenatal steroid exposure, compared with those without antenatal steroid exposure, were more likely to survive to discharge (adjusted odds ratio [aOR], 1.95 [95% CI, 1.07-3.56]) and to survive without major morbidity (aOR, 2.74 [95% CI, 1.19-6.30]).

Conclusions and Relevance

In this retrospective cohort study, among infants born between GA 22 0/7 and 23 6/7 weeks who received intensive care, exposure to a complete course of antenatal steroids at GA 22 6/7 weeks or less was independently associated with greater odds of survival and survival without major morbidity. These data suggest that the use of antenatal steroids in patients at GA 22 6/7 weeks or less could be beneficial when active treatment is considered.

Duration of skin-to-skin care and rectal temperatures in late preterm and term infants

Background

Hypothermia during the newborn period is widely regarded as a major contributory cause of significant morbidity and mortality of newborn infants. Thermoprotective behaviours such as skin-to-skin care (SSC) or the use of appropriate devices have been recommended as simple tools for the avoidance of neonatal hypothermia. We examined the relation between the duration of skin-to-skin care and infant temperature change after birth in suboptimal delivery room temperatures.

Methods

We reviewed the medical charts of all vaginally born infants of gestational age ≥ 35 weeks born January-July 2018 and admitted to the well-baby nursery. After SSC was discontinued, the infant’s rectal temperature was measured to determine the frequency and severity of hypothermia.

Results

The charts of 688 vaginally born infants were examined. Our mean delivery room temperature was 21.7 (SD 2.2) °C, well below the WHO recommendation of 25 °C. After SSC 347 (50.4%) infants were normothermic (temperature 36.5–37.5 °C), 262 (38.0%) were mildly hypothermic (36.0-36.4 °C), and 79 (11.4%) were moderately hypothermic (32.0-35.9 °C). The mean skin-to-skin time in infants was 63.9 (SD 20.9) minutes. SSC duration was associated with increase in rectal temperature for patients of gestational ages ≥ 38 weeks and with decrease in rectal temperature in patients of gestational age < 38 weeks.

Conclusion

SSC is effective, even at suboptimal delivery room temperatures, for promoting normothermia in infants of ≥ 38 weeks’ gestation but may not provide adequate warmth for infants of < 38 weeks.

Potential missed opportunities for antenatal corticosteroid exposure and outcomes among periviable births: observational cohort study

OBJECTIVE

Test the hypothesis potential missed opportunities for antenatal corticosteroids increase as gestational age decreases and are associated with adverse outcomes.

DESIGN

Observational cohort study.

SETTING

24 US centers in the Neonatal Research Network.

POPULATION

Actively treated infants 22-25 weeks' gestation and birth weight 401-1000 grams, without major birth defects, born 2006-2018.

METHODS

Potential missed opportunity was defined as no antenatal corticosteroids but did have prenatal antibiotics, and/or magnesium sulfate, and/or prolonged rupture of membranes. Poisson regression models adjusted for baseline characteristics.

MAIN OUTCOME MEASURES

Antenatal corticosteroid exposure, mortality, and severe intracranial hemorrhage or periventricular leukomalacia.

RESULTS

6966 (87.5%) were exposed to antenatal corticosteroids, 454 (5.7%) had no exposure but potential missed opportunities for antenatal corticosteroid exposure, and 537 (6.7%) had no exposure and no evidence of potential missed opportunities. Compared with infants born at 25 weeks, potential missed opportunities for antenatal corticosteroid exposure were more likely at 22 weeks (adjusted relative risk (aRR) [95% CI] 11.06 [7.52-16.27]) and 23 weeks (3.24 [2.44-4.29]) but did not differ at 24 weeks (1.08 [0.82-1.42]). Potential missed opportunities for antenatal corticosteroids decreased over time at 22-23 weeks' gestation. Antenatal corticosteroid exposed infants had lower risk of death (31.0% vs 54.8%; 0.77 [0.70-0.84]) and survivors had lower risk of severe brain injury (25.0% v 44.5%; 0.64 [0.55-0.73]) compared with infants with potential missed opportunities.

CONCLUSION

Potential missed opportunities for antenatal corticosteroid exposure increased with decreasing gestational age and were associated with higher rates of death and severe brain injury among actively treated periviable births.

Thyroxine and Thyroid-Stimulating Hormone in Own Mother’s Milk, Donor Milk, and Infant Formula

Breastfeeding is widely supported in clinical and home practices, and it is known that different forms of infant feeding differ in hormone content. Thyroid hormones have essential physiological roles. In our study, we examined thyroid-stimulating hormone (TSH), thyroxine, and albumin levels in breast milk produced for term (n = 16) or preterm (n = 15) infants throughout the first 6 months of lactation. Moreover, we analyzed these components in donor human milk and in three different infant formulas. Term and preterm breast milk samples were collected monthly. The two groups had similar levels of TSH (18.4 ± 1.4 vs. 24.7 ± 2.9 nU/L), but term milk contained higher amounts of thyroxine (11,245.5 ± 73.8 vs. 671.6 ± 61.2 nmol/L) during the examination period. The albumin level was significantly higher in preterm breast milk than in term breast milk (328.6 ± 17.1 vs. 264.2 ± 6.8 mg/L). In preterm breast milk we detected downward trends in the levels of TSH (−30.2%) and thyroxine (−29.2%) in the 3rd through 6th month compared to the first 2 months of lactation. Microbiological safety of donor milk was ensured by Holder pasteurization (HoP). From the Breast Milk Collection Center of Pécs, Hungary, we enrolled 44 donor mothers into the study. HoP decreased TSH (−73.8%), thyroxine (−22.4%), and albumin (−20.9%) concentrations. Infant formulas used by the Neonatal Intensive Care Unit of the University of Pécs were found to not contain the investigated hormones, but their albumin levels were similar to the breast milk samples. The present study shows the lack of thyroid hormones in infant formulas compared to human milk and raises the question of whether formula-fed infants should be supplemented with thyroid hormones.

Sex Differences in the Association of Pretransfusion Hemoglobin Levels with Brain Structure and Function in the Preterm Infant

OBJECTIVE

To assess sex-specific differences in early brain structure and function of preterm infants after red blood cell (RBC) transfusions.

STUDY DESIGN

A single-center subset of infants with a birth weight <1000 g and gestational age 22-29 weeks were enrolled from the National Institute of Child Health and Human Development's Neonatal Research Network Transfusion of Prematures Trial. Hemoglobin (Hb) concentration obtained directly before each transfusion (pretransfusion Hb [ptHb]) was obtained longitudinally throughout each infant's neonatal intensive care unit stay and used as a marker of degree of anemia (n = 97). Measures of regional brain volumes using magnetic resonance imaging were obtained at ∼40 weeks postmenstrual age or at hospital discharge, if earlier (n = 29). Measures of brain function were obtained at 12 months corrected age using the Bayley Scales of Infant & Toddler Development, 3rd Edition (n = 34).

RESULTS

PtHb was positively correlated with neonatal cerebral white matter volume in males (B = +0.283; P = .006), but not females (B = -0.099; P = .713), resulting in a significant sex interaction (P = .010). Bayley-III gross motor scores and a pooled mean score were significantly lower in association with higher ptHb in females (gross motor score: B = -3.758; P = .013; pooled mean score: B = -1.225; P = .030), but not males (gross motor score: B = +1.758; P = .167; pooled mean score: B = +0.621; P = .359). Higher ptHb was associated with descriptively lower performance on multiple Bayley-III subscales in females, but not in males.

CONCLUSIONS

This study demonstrates sex-specific associations between an early marker of anemia and RBC transfusion status (ie, ptHb) with both neonatal white matter volume and early cognitive function at age 12 months in preterm infants.

Hydrocortisone to Improve Survival without Bronchopulmonary Dysplasia

BACKGROUND

Bronchopulmonary dysplasia is a prevalent complication after extremely preterm birth. Inflammation with mechanical ventilation may contribute to its development. Whether hydrocortisone treatment after the second postnatal week can improve survival without bronchopulmonary dysplasia and without adverse neurodevelopmental effects is unknown.

METHODS

We conducted a trial involving infants who had a gestational age of less than 30 weeks and who had been intubated for at least 7 days at 14 to 28 days. Infants were randomly assigned to receive either hydrocortisone (4 mg per kilogram of body weight per day tapered over a period of 10 days) or placebo. Mandatory extubation thresholds were specified. The primary efficacy outcome was survival without moderate or severe bronchopulmonary dysplasia at 36 weeks of postmenstrual age, and the primary safety outcome was survival without moderate or severe neurodevelopmental impairment at 22 to 26 months of corrected age.

RESULTS

We enrolled 800 infants (mean [±SD] birth weight, 715±167 g; mean gestational age, 24.9±1.5 weeks). Survival without moderate or severe bronchopulmonary dysplasia at 36 weeks occurred in 66 of 398 infants (16.6%) in the hydrocortisone group and in 53 of 402 (13.2%) in the placebo group (adjusted rate ratio, 1.27; 95% confidence interval [CI], 0.93 to 1.74). Two-year outcomes were known for 91.0% of the infants. Survival without moderate or severe neurodevelopmental impairment occurred in 132 of 358 infants (36.9%) in the hydrocortisone group and in 134 of 359 (37.3%) in the placebo group (adjusted rate ratio, 0.98; 95% CI, 0.81 to 1.18). Hypertension that was treated with medication occurred more frequently with hydrocortisone than with placebo (4.3% vs. 1.0%). Other adverse events were similar in the two groups.

CONCLUSIONS

In this trial involving preterm infants, hydrocortisone treatment starting on postnatal day 14 to 28 did not result in substantially higher survival without moderate or severe bronchopulmonary dysplasia than placebo. Survival without moderate or severe neurodevelopmental impairment did not differ substantially between the two groups. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01353313.).

Sex-specific cytokine responses and neurocognitive outcome after blood transfusions in preterm infants

BACKGROUND

The objective of this study was to determine sex-specific differences in inflammatory cytokine responses to red blood cell (RBC) transfusion in preterm infants in the neonatal period and their relationship to later neurocognitive status.

METHODS

Infants with a birth weight <1000 g and gestational age 22-29 weeks were enrolled in the Transfusion of Prematures (TOP) trial. The total number of transfusions was used as a marker of transfusion status. Nineteen cytokines and biomarkers were analyzed from 71 infants longitudinally during the neonatal period. Twenty-six infants completed the Bayley Scales of Infant & Toddler Development, 3rd Edition (Bayley-III) at 12 months' corrected age.

RESULTS

Nine cytokine levels were significantly elevated in proportion to the number of transfusions received. Of those, one cytokine showed a sex-specific finding (p = 0.004): monocyte chemoattractant protein-1, MCP-1, rose substantially in females (8.9% change per additional transfusion), but not in males (-0.8% change). Higher concentrations of MCP-1 exclusively were associated with worse Bayley-III scores: decreased cognitive raw scores (p = 0.0005) and motor scaled scores (p < 0.0001).

CONCLUSIONS

This study provides evidence of a sex-specific difference in the inflammatory response to RBC transfusions during neonatal life, with MCP-1 levels rising only in females and inversely correlating with neurocognitive status at 12 months old.

IMPACT

It is important to understand the risk factors for abnormal neurodevelopment in preterm infants, including anemia and RBC transfusion, in order to improve outcomes and provide potential targets for therapy. Our study investigates and provides the first evidence of sex-specific differences in inflammatory cytokine responses to RBC transfusions in preterm infants in the neonatal period, and their relationship to later cognitive outcomes. This study critically suggests that different transfusion thresholds may have a sex-specific effect on neurodevelopment: females have worse cognitive outcomes with increased number of transfusions, while males have worse outcomes with lower number of transfusions.

Red cell transfusion thresholds for preterm infants: finally some answers

Extremely low birthweight infants become anaemic during their care in the neonatal intensive care unit because of the physiological anaemia experienced by all newborn infants compounded by early umbilical cord clamping, blood loss by phlebotomy for laboratory monitoring and delayed erythropoiesis. The majority of these infants receive transfusions of packed red blood cells, usually based on haemoglobin values below a certain threshold. The haemoglobin or haematocrit thresholds used to guide transfusion practices vary with infant status and among institutions and practitioners. Previous smaller studies have not given clear guidance with respect to the haemoglobin thresholds that should trigger transfusions or even if this is the best way to decide when to transfuse an infant. Two large clinical trials of similar design comparing higher and lower haemoglobin thresholds for transfusing extremely low birthweight infants were recently published, the ETTNO and TOP trials. These trials found reassuringly conclusive and concordant results. Within the range of haemoglobin transfusion thresholds studied, there was no difference in the primary outcome (which was the same in both studies), neurodevelopmental impairment at 2 years' corrected age or death before assessment, in either study. In addition, there was no difference in either study in either of the components of the primary outcome. In conclusion, haemoglobin transfusion thresholds within the ranges used in these trials, 11-13 g/dL for young critically ill or ventilated infants and 7-10 g/dL for stable infants not requiring significant respiratory support, can be safely used without expecting adverse consequences on survival or neurodevelopment.

Blanket temperature during therapeutic hypothermia and outcomes in hypoxic ischemic encephalopathy

OBJECTIVE

Determine whether blanket temperatures during therapeutic hypothermia (TH) are associated with 18-22 month outcomes for infants with hypoxic ischemic encephalopathy (HIE).

STUDY DESIGN

Retrospective cohort study of 181 infants with HIE who received TH in two randomized trials within the Neonatal Research Network. We defined summative blanket temperature constructs and evaluated for association with a primary composite outcome of death or moderate/ severe disability at 18-22 months.

RESULTS

Each 0.5 °C above 33.5 °C in the mean of the highest quartile blanket temperature was associated with a 52% increase in the adjusted odds of death/ disability (aOR 1.52, 95% CI 1.09-2.11). Having >8 consecutive blanket temperatures above 33.5 °C rendered an aOR of death/disability of 5.04 in the first 24 h (95% CI 1.54-16.6) and 6.92 in the first 48 h (95% CI 2.20-21.8) of TH.

CONCLUSIONS

Higher blanket temperature during TH may be an early, clinically useful biomarker of HIE outcome.

Fluid management considerations in extremely preterm infants born at 22-24 weeks of gestation

Emerging data regarding the encouraging outcomes of extremely preterm infants from centers taking active approaches to the care of these infants have prompted dialogue regarding optimal medical management. Among the multitude of decisions providers make in caring for extremely premature infants is the prescribing of parenteral fluids. Surprisingly, there are limited data to guide evidenced-based approaches to fluid and electrolyte management in this population. Immaturity of renal function and skin barriers contribute to the impaired capacity of the preterm infant to maintain salt and water homeostasis. This perspective paper highlights developmental physiological properties of the kidney and skin, which the provider needs to understand to provide parenteral fluid therapy. Additionally, we provide recommendations for initial fluid and electrolyte management of the preterm infant based on novel data as well as the published literature.

Mortality, In-Hospital Morbidity, Care Practices, and 2-Year Outcomes for Extremely Preterm Infants in the US, 2013-2018

IMPORTANCE

Despite improvement during recent decades, extremely preterm infants continue to contribute disproportionately to neonatal mortality and childhood morbidity.

OBJECTIVE

To review survival, in-hospital morbidities, care practices, and neurodevelopmental and functional outcomes at 22-26 months' corrected age for extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

Prospective registry for extremely preterm infants born at 19 US academic centers that are part of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. The study included 10 877 infants born at 22-28 weeks' gestational age between January 1, 2013, and December 31, 2018, including 2566 infants born before 27 weeks between January 1, 2013, and December 31, 2016, who completed follow-up assessments at 22-26 months' corrected age. The last assessment was completed on August 13, 2019. Outcomes were compared with a similar cohort of infants born in 2008-2012 adjusting for gestational age.

EXPOSURES

Extremely preterm birth.

MAIN OUTCOMES AND MEASURES

Survival and 12 in-hospital morbidities were assessed, including necrotizing enterocolitis, infection, intracranial hemorrhage, retinopathy of prematurity, and bronchopulmonary dysplasia. Infants were assessed at 22-26 months' corrected age for 12 health and functional outcomes, including neurodevelopment, cerebral palsy, vision, hearing, rehospitalizations, and need for assistive devices.

RESULTS

The 10 877 infants were 49.0% female and 51.0% male; 78.3% (8495/10848) survived to discharge, an increase from 76.0% in 2008-2012 (adjusted difference, 2.0%; 95% CI, 1.0%-2.9%). Survival to discharge was 10.9% (60/549) for live-born infants at 22 weeks and 94.0% (2267/2412) at 28 weeks. Survival among actively treated infants was 30.0% (60/200) at 22 weeks and 55.8% (535/958) at 23 weeks. All in-hospital morbidities were more likely among infants born at earlier gestational ages. Overall, 8.9% (890/9956) of infants had necrotizing enterocolitis, 2.4% (238/9957) had early-onset infection, 19.9% (1911/9610) had late-onset infection, 14.3% (1386/9705) had severe intracranial hemorrhage, 12.8% (1099/8585) had severe retinopathy of prematurity, and 8.0% (666/8305) had severe bronchopulmonary dysplasia. Among 2930 surviving infants with gestational ages of 22-26 weeks eligible for follow-up, 2566 (87.6%) were examined. By 2-year follow-up, 8.4% (214/2555) of children had moderate to severe cerebral palsy, 1.5% (38/2555) had bilateral blindness, 2.5% (64/2527) required hearing aids or cochlear implants, 49.9% (1277/2561) had been rehospitalized, and 15.4% (393/2560) required mobility aids or other supportive devices. Among 2458 fully evaluated infants, 48.7% (1198/2458) had no or mild neurodevelopmental impairment at follow-up, 29.3% (709/2419) had moderate neurodevelopmental impairment, and 21.2% (512/2419) had severe neurodevelopmental impairment.

CONCLUSIONS AND RELEVANCE

Among extremely preterm infants born in 2013-2018 and treated at 19 US academic medical centers, 78.3% survived to discharge, a significantly higher rate than for infants born in 2008-2012. Among infants born at less than 27 weeks' gestational age, rehospitalization and neurodevelopmental impairment were common at 2 years of age.

Association Between Increased Seizures During Rewarming After Hypothermia for Neonatal Hypoxic Ischemic Encephalopathy and Abnormal Neurodevelopmental Outcomes at 2-Year Follow-up: A Nested Multisite Cohort Study

Importance

Compared with normothermia, hypothermia has been shown to reduce death or disability in neonatal hypoxic ischemic encephalopathy but data on seizures during rewarming and associated outcomes are scarce.

Objective

To determine whether electrographic seizures are more likely to occur during rewarming compared with the preceding period and whether they are associated with abnormal outcomes in asphyxiated neonates receiving hypothermia therapy.

Design, Setting, and Participants

This prespecified nested cohort study of infants enrolled in the Optimizing Cooling (OC) multicenter Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network trial from December 2011 to December 2013 with 2 years' follow-up randomized infants to either 72 hours of cooling (group A) or 120 hours (group B). The main trial included 364 infants. Of these, 194 were screened, 10 declined consent, and 120 met all predefined inclusion criteria. A total of 112 (90%) had complete data for death or disability. Data were analyzed from January 2018 to January 2020.

Interventions

Serial amplitude electroencephalography recordings were compared in the 12 hours prior and 12 hours during rewarming for evidence of electrographic seizure activity by 2 central amplitude-integrated electroencephalography readers blinded to treatment arm and rewarming epoch. Odds ratios and 95% CIs were evaluated following adjustment for center, prior seizures, depth of cooling, and encephalopathy severity.

Main Outcomes and Measures

The primary outcome was the occurrence of electrographic seizures during rewarming initiated at 72 or 120 hours compared with the preceding 12-hour epoch. Secondary outcomes included death or moderate or severe disability at age 18 to 22 months. The hypothesis was that seizures during rewarming were associated with higher odds of abnormal neurodevelopmental outcomes.

Results

A total of 120 newborns (70 male [58%]) were enrolled (66 in group A and 54 in group B). The mean (SD) gestational age was 39 (1) weeks. There was excellent interrater agreement (κ, 0.99) in detection of seizures. More infants had electrographic seizures during the rewarming epoch compared with the preceding epoch (group A, 27% vs 14%; P = .001; group B, 21% vs 10%; P = .03). Adjusted odd ratios (95% CIs) for seizure frequency during rewarming were 2.7 (1.0-7.5) for group A and 3.2 (0.9-11.6) for group B. The composite death or moderate to severe disability outcome at 2 years was significantly higher in infants with electrographic seizures during rewarming (relative risk [95% CI], 1.7 [1.25-2.37]) after adjusting for baseline clinical encephalopathy and seizures as well as center.

Conclusions and Relevance

Findings that higher odds of electrographic seizures during rewarming are associated with death or disability at 2 years highlight the necessity of electroencephalography monitoring during rewarming in infants at risk.

Trial Registration

ClinicalTrials.gov Identifier: NCT01192776.

Initial Laparotomy Versus Peritoneal Drainage in Extremely Low Birthweight Infants With Surgical Necrotizing Enterocolitis or Isolated Intestinal Perforation: A Multicenter Randomized Clinical Trial

OBJECTIVE

The aim of this study was to determine which initial surgical treatment results in the lowest rate of death or neurodevelopmental impairment (NDI) in premature infants with necrotizing enterocolitis (NEC) or isolated intestinal perforation (IP).

SUMMARY BACKGROUND DATA

The impact of initial laparotomy versus peritoneal drainage for NEC or IP on the rate of death or NDI in extremely low birth weight infants is unknown.

METHODS

We conducted the largest feasible randomized trial in 20 US centers, comparing initial laparotomy versus peritoneal drainage. The primary outcome was a composite of death or NDI at 18 to 22 months corrected age, analyzed using prespecified frequentist and Bayesian approaches.

RESULTS

Of 992 eligible infants, 310 were randomized and 96% had primary outcome assessed. Death or NDI occurred in 69% of infants in the laparotomy group versus 70% with drainage [adjusted relative risk (aRR) 1.0; 95% confidence interval (CI): 0.87-1.14]. A preplanned analysis identified an interaction between preoperative diagnosis and treatment group (P = 0.03). With a preoperative diagnosis of NEC, death or NDI occurred in 69% after laparotomy versus 85% with drainage (aRR 0.81; 95% CI: 0.64-1.04). The Bayesian posterior probability that laparotomy was beneficial (risk difference <0) for a preoperative diagnosis of NEC was 97%. For preoperative diagnosis of IP, death or NDI occurred in 69% after laparotomy versus 63% with drainage (aRR, 1.11; 95% CI: 0.95-1.31); Bayesian probability of benefit with laparotomy = 18%.

CONCLUSIONS

There was no overall difference in death or NDI rates at 18 to 22 months corrected age between initial laparotomy versus drainage. However, the preoperative diagnosis of NEC or IP modified the impact of initial treatment.

Growth Rates of Infants Randomized to Continuous Positive Airway Pressure or Intubation After Extremely Preterm Birth

OBJECTIVE

To evaluate the effects of early treatment with continuous positive airway pressure (CPAP) on nutritional intake and in-hospital growth rates of extremely preterm (EPT) infants.

STUDY DESIGN

EPT infants (24^0/7-27^6/7 weeks of gestation) enrolled in the Surfactant Positive Airway Pressure and Pulse Oximetry Trial (SUPPORT) were included. EPT infants who died before 36 weeks of postmenstrual age (PMA) were excluded. The growth rates from birth to 36 weeks of PMA and follow-up outcomes at 18-22 months corrected age of EPT infants randomized at birth to either early CPAP (intervention group) or early intubation for surfactant administration (control group) were analyzed.

RESULTS

Growth data were analyzed for 810 of 1316 infants enrolled in SUPPORT (414 in the intervention group, 396 in the control group). The median gestational age was 26 weeks, and the mean birth weight was 839 g. Baseline characteristics, total nutritional intake, and in-hospital comorbidities were not significantly different between the 2 groups. In a regression model, growth rates between birth and 36 weeks of PMA, as well as growth rates during multiple intervals from birth to day 7, days 7-14, days 14-21, days 21-28, day 28 to 32 weeks PMA, and 32-36 weeks PMA did not differ between treatment groups. Independent of treatment group, higher growth rates from day 21 to day 28 were associated with a lower risk of having a Bayley-III cognitive score <85 at 18-22 months corrected age (P = .002).

CONCLUSIONS

EPT infants randomized to early CPAP did not have higher in-hospital growth rates than infants randomized to early intubation.

Neurodevelopmental outcomes following neonatal late-onset sepsis and blood culture-negative conditions

OBJECTIVE

Determine risk of death or neurodevelopmental impairment (NDI) in infants with late-onset sepsis (LOS) versus late-onset, antibiotic-treated, blood culture-negative conditions (LOCNC).

DESIGN

Retrospective cohort study.

SETTING

24 neonatal centres.

PATIENTS

Infants born 1/1/2006-31/12/2014, at 22-26 weeks gestation, with birth weight 401-1000 g and surviving >7 days were included. Infants with early-onset sepsis, necrotising enterocolitis, intestinal perforation or both LOS and LOCNC were excluded.

EXPOSURES

LOS and LOCNC were defined as antibiotic administration for ≥5 days with and without a positive blood/cerebrospinal fluid culture, respectively. Infants with these diagnoses were also compared with infants with neither condition.

OUTCOMES

Death or NDI was assessed at 18-26 months corrected age follow-up. Modified Poisson regression models were used to estimate relative risks adjusting for covariates occurring ≤7 days of age.

RESULTS

Of 7354 eligible infants, 3940 met inclusion criteria: 786 (20%) with LOS, 1601 (41%) with LOCNC and 1553 (39%) with neither. Infants with LOS had higher adjusted relative risk (95% CI) for death/NDI (1.14 (1.05 to 1.25)) and death before follow-up (1.71 (1.44 to 2.03)) than those with LOCNC. Among survivors, risk for NDI did not differ between the two groups (0.99 (0.86 to 1.13)) but was higher for LOCNC infants (1.17 (1.04 to 1.31)) compared with unaffected infants.

CONCLUSIONS

Infants with LOS had higher risk of death, but not NDI, compared with infants with LOCNC. Surviving infants with LOCNC had higher risk of NDI compared with unaffected infants. Improving outcomes for infants with LOCNC requires study of the underlying conditions and the potential impact of antibiotic exposure.

Eligibility Criteria and Representativeness of Randomized Clinical Trials That Include Infants Born Extremely Premature: A Systematic Review

OBJECTIVE

To assess the eligibility criteria and trial characteristics among contemporary (2010-2019) randomized clinical trials (RCTs) that included infants born extremely preterm (<28 weeks of gestation) and to evaluate whether eligibility criteria result in underrepresentation of high-risk subgroups (eg, infants born at <24 weeks of gestation).

STUDY DESIGN

PubMed and Scopus were searched January 1, 2010, to December 31, 2019, with no language restrictions. RCTs with mean or median gestational ages at birth of <28 weeks of gestation were included. The study followed the PRISMA guidelines; outcomes were registered prospectively. Data extraction was performed independently by multiple observers. Study quality was evaluated using a modified Jadad scale.

RESULTS

Among RCTs (n = 201), 32 552 infants were included. Study participant characteristics, interventions, and outcomes were highly variable. A total of 1603 eligibility criteria were identified; rationales were provided for 18.8% (n = 301) of criteria. Fifty-five RCTs (27.4%) included infants <24 weeks of gestation; 454 (1.4%) infants were identified as <24 weeks of gestation.

CONCLUSIONS

The present study identifies sources of variability across RCTs that included infants born extremely preterm and reinforces the critical need for consistent and transparent policies governing eligibility criteria.

Validation of the Postnatal Growth and Retinopathy of Prematurity Screening Criteria

Importance

The first Postnatal Growth and Retinopathy of Prematurity Study (G-ROP-1) developed new screening criteria with 100% sensitivity for type 1 retinopathy of prematurity (ROP) and 30% reduction of infants requiring examinations in a retrospective development cohort of 7483 infants from 29 North American hospitals in 2006-2012. Infants meeting 1 or more of the following criteria undergo examinations: gestational age less than 28 weeks or birth weight less than 1051 g; weight gain less than 120 g during age 10 to 19 days, weight gain less than 180 g during age 20 to 29 days, or weight gain less than 170 g during age 30 to 39 days; or hydrocephalus.

Objective

To evaluate the generalizability of the G-ROP screening criteria in a new cohort of at-risk infants.

Design, Setting, and Participants

This prospective validation cohort study (G-ROP-2) was conducted at 41 hospitals in the United States and Canada (25 G-ROP-1 hospitals and 16 new hospitals) from September 8, 2015, to June 13, 2017, among 3981 premature infants at risk for ROP and with known ROP outcomes.

Main Outcomes and Measures

Sensitivity for Early Treatment for Retinopathy of Prematurity Study type 1 ROP and potential reduction in infants receiving examinations.

Results

Among the 3981 infants in the study (1878 girls and 2103 boys; median gestational age, 28 weeks [range, 22-35 weeks]; median birth weight, 1072 g [range, 350-4080 g]; 1966 white; 942 black; 321 Latino; 120 Asian; 22 Native Hawaian or Pacific Islander; and 25 American Indian or Alaskan Native), the G-ROP criteria correctly predicted 219 of 219 cases of type 1 ROP (sensitivity, 100%; 95% CI, 98.3%-100%), while reducing the number of infants undergoing examinations by 35.6% (n = 1418). In a combined G-ROP-1 and G-ROP-2 cohort of 11 463 infants, the G-ROP criteria predicted 677 of 677 cases of type 1 ROP (sensitivity, 100%; 95% CI, 99.4%-100%), reducing the number of infants receiving examinations by 32.5% (n = 3730), while current criteria (birth weight <1501 g or gestational age ≤30 weeks 0 days) predicted 674 of 677 type 1 cases (sensitivity, 99.6%; 95% CI, 98.7%-99.8%).

Conclusions and Relevance

This study found that the G-ROP screening criteria were generalizable on validation and, if used clinically in the United States and Canada, could reduce the number of infants receiving examinations. The large G-ROP cohorts provide evidence-based screening criteria that have higher sensitivity and higher specificity (fewer infants receiving examinations) for type 1 ROP than currently recommended guidelines.

In-hospital mortality and morbidity among extremely preterm infants in relation to maternal body mass index

OBJECTIVE

The objective of this paper is to compare in-hospital survival and survival without major morbidities in extremely preterm infants in relation to maternal body mass index (BMI).

METHODS

This retrospective cohort study included extremely preterm infants (gestational age 220/7-286/7 weeks). This study was conducted at National Institute of Child Health and Human Development Neonatal Research Network sites. Primary outcome was survival without any major morbidity.

RESULTS

Maternal BMI data were available for 2415 infants. Survival without any major morbidity was not different between groups: 30.8% in the underweight/normal, 28.1% in the overweight, and 28.5% in the obese (P = 0.65). However, survival was lower in the obese group (76.5%) compared with overweight group (83.2%) (P = 0.02). Each unit increase in maternal BMI was associated with decreased odds of infant survival (P < 0.01).

CONCLUSIONS

Survival without any major morbidity was not associated with maternal obesity. An increase in maternal prepregnancy BMI was associated with decreased odds of infant survival.

Withholding or withdrawing life-sustaining treatment in extremely low gestational age neonates

OBJECTIVE

To identify sociodemographic and clinical factors associated with withholding or withdrawing life-sustaining treatment (WWLST) for extremely low gestational age neonates.

DESIGN

Observational study of prospectively collected registry data from 19 National Institute of Child Health and Human Development Neonatal Research Network centres on neonates born at 22-28 weeks gestation who died >12 hours through 120 days of age during 2011-2016. Sociodemographic and clinical factors were compared between infants who died following WWLST and without WWLST.

RESULTS

Of 1168 deaths, 67.1% occurred following WWLST. Withdrawal of assisted ventilation (97.4%) was the primary modality. WWLST rates were inversely proportional to gestational age. Life-sustaining treatment was withheld or withdrawn more often for non-Hispanic white infants than for non-Hispanic black infants (72.7% vs 60.4%; 95% CI 1.00 to 1.92) or Hispanic infants (72.7% vs 67.2%; 95% CI 1.32 to 3.72). WWLST rates varied across centres (38.6-92.6%; p<0.001). The centre with the highest rate had adjusted odds 4.89 times greater than the average (95% CI 1.18 to 20.18). The adjusted odds of WWLST were higher for infants with necrotiing enterocolitis (OR 1.77, 95% CI 1.21 to 2.59) and severe brain injury (OR 1.98, 95% CI 1.44 to 2.74).

CONCLUSIONS

Among infants who died, WWLST rates varied widely across centres and were associated with gestational age, race, ethnicity, necrotiing enterocolitis, and severe brain injury. Further exploration is needed into how race, centre, and approaches to care of infants with necrotiing enterocolitis and severe brain injury influence WWLST.

Limitations of Conventional Magnetic Resonance Imaging as a Predictor of Death or Disability Following Neonatal Hypoxic-Ischemic Encephalopathy in the Late Hypothermia Trial

OBJECTIVE

To investigate if magnetic resonance imaging (MRI) is an accurate predictor for death or moderate-severe disability at 18-22 months of age among infants with neonatal encephalopathy in a trial of cooling initiated at 6-24 hours.

STUDY DESIGN

Subgroup analysis of infants ≥36 weeks of gestation with moderate-severe neonatal encephalopathy randomized at 6-24 postnatal hours to hypothermia or usual care in a multicenter trial of late hypothermia. MRI scans were performed per each center's practice and interpreted by 2 central readers using the Eunice Kennedy Shriver National Institute of Child Health and Human Development injury score (6 levels, normal to hemispheric devastation). Neurodevelopmental outcomes were assessed at 18-22 months of age.

RESULTS

Of 168 enrollees, 128 had an interpretable MRI and were seen in follow-up (n = 119) or died (n = 9). MRI findings were predominantly acute injury and did not differ by cooling treatment. At 18-22 months, death or severe disability occurred in 20.3%. No infant had moderate disability. Agreement between central readers was moderate (weighted kappa 0.56, 95% CI 0.45-0.67). The adjusted odds of death or severe disability increased 3.7-fold (95% CI 1.8-7.9) for each increment of injury score. The area under the curve for severe MRI patterns to predict death or severe disability was 0.77 and the positive and negative predictive values were 36% and 100%, respectively.

CONCLUSIONS

MRI injury scores were associated with neurodevelopmental outcome at 18-22 months among infants in the Late Hypothermia Trial. However, the results suggest caution when using qualitative interpretations of MRI images to provide prognostic information to families following perinatal hypoxia-ischemia.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT00614744.

Proactive neonatal treatment at 22 weeks of gestation: a systematic review and meta-analysis

OBJECTIVE

The objective of this study was to provide a systematic review and meta-analysis to quantify prognosis and identify factors associated with variations in reported mortality estimates among infants who were born at 22 weeks of gestation and provided proactive treatment (resuscitation and intensive care).

DATA SOURCES

PubMed, Scopus, and Web of Science databases, with no language restrictions, were searched for articles published from January 2000 to February 2020.

STUDY ELIGIBILITY CRITERIA

Reports on live-born infants who were delivered at 22 weeks of gestation and provided proactive care were included. The primary outcome was survival to hospital discharge; secondary outcomes included survival without major morbidity and survival without neurodevelopmental impairment. Because we expected differences across studies in the definitions for various morbidities, multiple definitions for composite outcomes of major morbidities were prespecified. Neurodevelopmental impairment was based on Bayley Scales of Infant Development II or III. Data extractions were performed independently, and outcomes agreed on a priori.

STUDY APPRAISAL AND SYNTHESIS METHODS

Methodological quality was assessed using the Quality in Prognostic Studies tool. An adapted version of the Grading of Recommendations Assessment, Development and Evaluation approach for prognostic studies was used to evaluate confidence in overall estimates. Outcomes were assessed as prevalence and 95% confidence intervals. Variabilities across studies attributable to heterogeneity were estimated with the I² statistic; publication bias was assessed with the Luis Furuya-Kanamori index. Data were pooled using the inverse variance heterogeneity model.

RESULTS

Literature searches returned 21,952 articles, with 2034 considered in full; 31 studies of 2226 infants who were delivered at 22 weeks of gestation and provided proactive neonatal treatment were included. No articles were excluded for study design or risk of bias. The pooled prevalence of survival was 29.0% (95% confidence interval, 17.2-41.6; 31 studies, 2226 infants; I²=79.4%; Luis Furuya-Kanamori index=0.04). Survival among infants born to mothers receiving antenatal corticosteroids was twice the survival of infants born to mothers not receiving antenatal corticosteroids (39.0% vs 19.5%; P<.01). The overall prevalence of survival without major morbidity, using a definition that includes any bronchopulmonary dysplasia, was 11.0% (95% confidence interval, 8.0-14.3; 10 studies, 374 infants; I²=0%; Luis Furuya-Kanamori index=3.02). The overall rate of survival without moderate or severe impairment was 37.0% (95% confidence interval, 14.6-61.5; 5 studies, 39 infants; I²=45%; Luis Furuya-Kanamori index=-0.15). Based on the year of publication, survival rates increased between 2000 and 2020 (slope of the regression line=0.09; standard error=0.03; P<.01). Studies were highly diverse with regard to interventions and outcomes reported.

CONCLUSION

The reported survival rates varied greatly among studies and were likely influenced by combining observational data from disparate sources, lack of individual patient-level data, and bias in the component studies from which the data were drawn. Therefore, pooled results should be interpreted with caution. To answer fundamental questions beyond the breadth of available data, multicenter, multidisciplinary collaborations, including alignment of important outcomes by stakeholders, are needed.

Breast Milk for Term and Preterm Infants-Own Mother's Milk or Donor Milk?

Hormones are important biological regulators, controlling development and physiological processes throughout life. We investigated pituitary hormones such as follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL) and total protein levels during the first 6 months of lactation. Breast milk samples were collected every fourth week of lactation from mothers who gave birth to preterm (n = 14) or term (n = 16) infants. Donor milk is suggested when own mother’s milk is not available; therefore, we collected breast milk samples before and after Holder pasteurization (HoP) from the Breast Milk Collection Center of Pécs, Hungary. Three infant formulas prepared in the Neonatal Intensive Care Unit of the University of Pécs were tested at three different time points. Our aim was to examine the hormone content of own mother’s milk and donor milk. There were no significant changes over time in the concentrations of any hormone. Preterm milk had higher PRL (28.2 ± 2.5 vs. 19.3 ± 2.3 ng/mL) and LH (36.3 ± 8.8 vs. 15.9 ± 4.1 mIU/L) concentrations than term milk during the first 6 months of lactation. Total protein and FSH concentrations did not differ between preterm and term breast milk. Holder pasteurization decreased the PRL concentration (30.4 ± 1.8 vs. 14.4 ± 0.6 ng/mL) and did not affect gonadotropin levels of donor milk. Infant formulas have higher total protein content than breast milk but do not contain detectable levels of pituitary hormones. Differences were detected in the content of pituitary hormones produced for preterm and term infants. Divergence between feeding options offers opportunities for improvement of nutritional guidelines for both hospital and home feeding practices.

The relationship of neurodevelopmental impairment to concurrent early childhood outcomes of extremely preterm infants

OBJECTIVE

Determine how neurodevelopmental impairment (NDI) relates to concurrent outcomes for children born extremely preterm.

STUDY DESIGN

Retrospective cohort study children born 22 0/7-26 6/7 weeks' gestation at NICHD Neonatal Research Network hospitals. Outcomes were ascertained at 18-22 months' corrected age.

RESULT

Of 6562 children, 2618 (40%) died and 441 (7%) had no follow-up. Among the remaining 3483 children, 825 (24%), 1576 (45%), 657 (19%), and 425 (12%) had no, potential/mild, moderate, and severe NDI, respectively. Rehospitalization, respiratory medications, surgery, and medical support services were associated with greater NDI severity but affected >10% of children without NDI. Rehospitalization occurred in 40% of children with no NDI (mean (SD): 1.7 (1.3) episodes).

CONCLUSION

Medical, functional, and social outcomes at 18-22 months' corrected age were associated with NDI; however, many children without NDI were affected. These data should contribute to counseling families and the design of studies for childhood outcomes beyond NDI.

Higher or Lower Hemoglobin Transfusion Thresholds for Preterm Infants

BACKGROUND

Limited data suggest that higher hemoglobin thresholds for red-cell transfusions may reduce the risk of cognitive delay among extremely-low-birth-weight infants with anemia.

METHODS

We performed an open, multicenter trial in which infants with a birth weight of 1000 g or less and a gestational age between 22 weeks 0 days and 28 weeks 6 days were randomly assigned within 48 hours after delivery to receive red-cell transfusions at higher or lower hemoglobin thresholds until 36 weeks of postmenstrual age or discharge, whichever occurred first. The primary outcome was a composite of death or neurodevelopmental impairment (cognitive delay, cerebral palsy, or hearing or vision loss) at 22 to 26 months of age, corrected for prematurity.

RESULTS

A total of 1824 infants (mean birth weight, 756 g; mean gestational age, 25.9 weeks) underwent randomization. There was a between-group difference of 1.9 g per deciliter (19 g per liter) in the pretransfusion mean hemoglobin levels throughout the treatment period. Primary outcome data were available for 1692 infants (92.8%). Of 845 infants in the higher-threshold group, 423 (50.1%) died or survived with neurodevelopmental impairment, as compared with 422 of 847 infants (49.8%) in the lower-threshold group (relative risk adjusted for birth-weight stratum and center, 1.00; 95% confidence interval [CI], 0.92 to 1.10; P = 0.93). At 2 years, the higher- and lower-threshold groups had similar incidences of death (16.2% and 15.0%, respectively) and neurodevelopmental impairment (39.6% and 40.3%, respectively). At discharge from the hospital, the incidences of survival without severe complications were 28.5% and 30.9%, respectively. Serious adverse events occurred in 22.7% and 21.7%, respectively.

CONCLUSIONS

In extremely-low-birth-weight infants, a higher hemoglobin threshold for red-cell transfusion did not improve survival without neurodevelopmental impairment at 22 to 26 months of age, corrected for prematurity. (Funded by the National Heart, Lung, and Blood Institute and others; TOP ClinicalTrials.gov number, NCT01702805.).

Hormone levels in preterm and donor human milk before and after Holder pasteurization

BACKGROUND

After birth, breastfeeding is the exclusive source of hormonal signaling between mother and infant. Hospitalized infants often receive donor milk when their own mother's milk is unavailable.

METHODS

The presence of insulin, leptin, cortisol, progesterone, and testosterone was examined in samples from milk bank donors and mothers of preterm infants. We further investigated the effect of Holder pasteurization (HoP) on hormone levels.

RESULTS

Comparing nonpasteurized samples, leptin levels were nearly threefold higher in milk from mothers of preterm infants versus donated milk, and regardless of milk source, leptin levels were significantly decreased by HoP. Insulin concentrations were also decreased by HoP, and among mothers of preterm infants, obesity was associated with significantly higher content of leptin and insulin. While combined use of donor milk and HoP was associated with cortisol levels nearly threefold higher than those in nonpasteurized own mother's milk, progesterone and testosterone content did not differ by source or pasteurization.

CONCLUSIONS

The hormonal composition of breast milk is impacted by HoP and maternal obesity. Compared to nonpasteurized maternal milk, use of pasteurized donor milk dramatically decreases the intake of leptin while increasing the intake of cortisol. Further research is necessary to define optimal breast milk processing practices.

Survey of practices in relation to chronic pulmonary hypertension in neonates in the Canadian Neonatal Network and the National Institute of Child Health and Human Development Neonatal Research Network

Current knowledge gaps pertaining to diagnosis and management of neonatal chronic pulmonary hypertension (cPH) may result in significant variability in clinical practice. The objective of the study is to understand cPH management practices in neonatal intensive care units affiliated with the Canadian Neonatal Network (CNN) and National Institute of Child Health and Human Development Neonatal Research Network (NRN). A 32-question survey seeking practice details for cPH evaluation, diagnostic criteria, conservative measures, pharmacotherapeutics, and follow-up was e-mailed to a designated physician at each center. Responses were described as frequency (percentage) and compared between CNN and NRN, where appropriate. Overall response rate was 67% (CNN 20/28 (71%), NRN 9/15 (60%)). While 8 (28%) centers had standardized management protocols, 17 (59%) routinely evaluate high-risk patients; moderate-severe chronic lung disease being the commonest indication. While interventricular septal flattening on echocardiography was the commonest listed diagnostic criterion, several adjunctive indices were also identified. Asymptomatic neonates with cPH were managed expectantly (routine care) in 50% of sites, and using various conservative measures in others. Pulmonary vasodilators were prescribed for symptomatic cases, with 60% of sites using them early (86% reporting any use). Seventy-five percent of sites use inhaled nitric oxide and sildenafil citrate as first- and second-line agents, respectively. Use of standard protocols, cardiac catheterization, and conservative measures for asymptomatic cases was more common in NRN units (p < 0.05). While there is relative homogeneity in patient identification and diagnostic criteria used for neonatal cPH, significant interunit inconsistencies still exists in routine evaluation, use of additional investigations, management of asymptomatic cases, frequency and type of conservative measures, and choice of pulmonary vasodilators.

Early-Onset Neonatal Sepsis 2015 to 2017, the Rise of Escherichia coli, and the Need for Novel Prevention Strategies

IMPORTANCE

Early-onset sepsis (EOS) remains a potentially fatal newborn condition. Ongoing surveillance is critical to optimize prevention and treatment strategies.

OBJECTIVE

To describe the current incidence, microbiology, morbidity, and mortality of EOS among a cohort of term and preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

This prospective surveillance study included a cohort of infants born at a gestational age (GA) of at least 22 weeks and birth weight of greater than 400 g from 18 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network from April 1, 2015, to March 31, 2017. Data were analyzed from June 14, 2019, to January 28, 2020.

MAIN OUTCOMES AND MEASURES

Early-onset sepsis defined by isolation of pathogenic species from blood or cerebrospinal fluid culture within 72 hours of birth and antibiotic treatment for at least 5 days or until death.

RESULTS

A total of 235 EOS cases (127 male [54.0%]) were identified among 217 480 newborns (1.08 [95% CI, 0.95-1.23] cases per 1000 live births). Incidence varied significantly by GA and was highest among infants with a GA of 22 to 28 weeks (18.47 [95% CI, 14.57-23.38] cases per 1000). No significant differences in EOS incidence were observed by sex, race, or ethnicity. The most frequent pathogens were Escherichia coli (86 [36.6%]) and group B streptococcus (GBS; 71 [30.2%]). E coli disease primarily occurred among preterm infants (68 of 131 [51.9%]); GBS disease primarily occurred among term infants (54 of 104 [51.9%]), with 24 of 45 GBS cases (53.3%) seen in infants born to mothers with negative GBS screening test results. Intrapartum antibiotics were administered to 162 mothers (68.9%; 110 of 131 [84.0%] preterm and 52 of 104 [50.0%] term), most commonly for suspected chorioamnionitis. Neonatal empirical antibiotic treatment most frequently included ampicillin and gentamicin. All GBS isolates were tested, but only 18 of 81 (22.2%) E coli isolates tested were susceptible to ampicillin; 6 of 77 E coli isolates (7.8%) were resistant to both ampicillin and gentamicin. Nearly all newborns with EOS (220 of 235 [93.6%]) displayed signs of illness within 72 hours of birth. Death occurred in 38 of 131 infected infants with GA of less than 37 weeks (29.0%); no term infants died. Compared with earlier surveillance (2006-2009), the rate of E coli infection increased among very low-birth-weight (401-1500 g) infants (8.68 [95% CI, 6.50-11.60] vs 5.07 [95% CI, 3.93-6.53] per 1000 live births; P = .008).

CONCLUSIONS AND RELEVANCE

In this study, EOS incidence and associated mortality disproportionately occurred in preterm infants. Contemporary cases have demonstrated the limitations of current GBS prevention strategies. The increase in E coli infections among very low-birth-weight infants warrants continued study. Ampicillin and gentamicin remained effective antibiotics in most cases, but ongoing surveillance should monitor antibiotic susceptibilities of EOS pathogens.

Racial/Ethnic Disparities Among Extremely Preterm Infants in the United States From 2002 to 2016

IMPORTANCE

Racial/ethnic disparities in quality of care among extremely preterm infants are associated with adverse outcomes.

OBJECTIVE

To assess whether racial/ethnic disparities in major outcomes and key care practices were changing over time among extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

This observational cohort study used prospectively collected data from 25 US academic medical centers. Participants included 20 092 infants of 22 to 27 weeks' gestation with a birth weight of 401 to 1500 g born at centers participating in the National Institute of Child Health and Human Development Neonatal Research Network from 2002 to 2016. Of these infants, 9316 born from 2006 to 2014 were eligible for follow-up at 18 to 26 months' postmenstrual age (excluding 5871 infants born before 2006, 2594 infants born after 2014, and 2311 ineligible infants including 64 with birth weight >1000 g and 2247 infants with gestational age >26 6/7 weeks), of whom 745 (8.0%) did not have known follow-up outcomes at 18 to 26 months.

MAIN OUTCOMES AND MEASURES

Rates of mortality, major morbidities, and care practice use over time were evaluated using models adjusted for baseline characteristics, center, and birth year. Data analyses were conducted from 2018 to 2019.

RESULTS

In total, 20 092 infants with a mean (SD) gestational age of 25.1 (1.5) weeks met the inclusion criteria and were available for the primary outcome: 8331 (41.5%) black infants, 3701 (18.4%) Hispanic infants, and 8060 (40.1%) white infants. Hospital mortality decreased over time in all groups. The rate of improvement in hospital mortality over time did not differ among black and Hispanic infants compared with white infants (black infants went from 35% to 24%, Hispanic infants went from 32% to 27%, and white infants went from 30% to 22%; P = .59 for race × year interaction). The rates of late-onset sepsis among black infants (went from 37% to 24%) and Hispanic infants (went from 45% to 23%) were initially higher than for white infants (went from 36% to 25%) but decreased more rapidly and converged during the most recent years (P = .02 for race × year interaction). Changes in rates of other major morbidities did not differ by race/ethnicity. Death before follow-up decreased over time (from 2006 to 2014: black infants, 14%; Hispanic infants, 39%, white infants, 15%), but moderate-severe neurodevelopmental impairment increased over time in all racial/ethnic groups (increase from 2006 to 2014: black infants, 70%; Hispanic infants, 123%; white infants, 130%). Rates of antenatal corticosteroid exposure (black infants went from 72% to 90%, Hispanic infants went from 73% to 83%, and white infants went from 86% to 90%; P = .01 for race × year interaction) and of cesarean delivery (black infants went from 45% to 59%, Hispanic infants went from 49% to 59%, and white infants went from 62% to 63%; P = .03 for race × year interaction) were initially lower among black and Hispanic infants compared with white infants, but these differences decreased over time.

CONCLUSIONS AND RELEVANCE

Among extremely preterm infants, improvements in adjusted rates of mortality and most major morbidities did not differ by race/ethnicity, but rates of neurodevelopmental impairment increased in all groups. There were narrowing racial/ethnic disparities in important care practices, including the use of antenatal corticosteroids and cesarean delivery.

Impact of Early-Onset Sepsis and Antibiotic Use on Death or Survival with Neurodevelopmental Impairment at 2 Years of Age among Extremely Preterm Infants

OBJECTIVE

To evaluate the hypothesis that early-onset sepsis increases risk of death or neurodevelopmental impairment (NDI) among preterm infants; and that among infants without early-onset sepsis, prolonged early antibiotics alters risk of death/NDI.

STUDY DESIGN

Retrospective cohort study of infants born at the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network centers (2006-2014) at 22-26 weeks of gestation and birth weight 401-1000 g. Early-onset sepsis defined as growth of a pathogen from blood or cerebrospinal fluid culture ≤72 hours after birth. Prolonged early antibiotics was defined as antibiotics initiated ≤72 hours and continued ≥5 days without culture-confirmed infection, necrotizing enterocolitis, or spontaneous perforation. Primary outcome was death before follow-up or NDI assessed at 18-26 months corrected age. Poisson regression was used to estimate adjusted relative risk (aRR) and CI for early-onset sepsis outcomes. A propensity score for receiving prolonged antibiotics was derived from early clinical factors and used to match infants (1:1) with and without prolonged antibiotic exposure. Log binomial models were used to estimate aRR for outcomes in matched infants.

RESULTS

Among 6565 infants, those with early-onset sepsis had higher aRR (95% CI) for death/NDI compared with infants managed with prolonged antibiotics (1.18 [1.06-1.32]) and to infants without prolonged antibiotics (1.23 [1.10-1.37]). Propensity score matching was achieved for 4362 infants. No significant difference in death/NDI (1.04 [0.98-1.11]) was observed with or without prolonged antibiotics among the matched cohort.

CONCLUSIONS

Early-onset sepsis was associated with increased risk of death/NDI among extremely preterm infants. Among matched infants without culture-confirmed infection, prolonged early antibiotic administration was not associated with death/NDI.

Assessment of an Updated Neonatal Research Network Extremely Preterm Birth Outcome Model in the Vermont Oxford Network

IMPORTANCE

The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) extremely preterm birth outcome model is widely used for prognostication by practitioners caring for families expecting extremely preterm birth. The model provides information on mean outcomes from 1998 to 2003 and does not account for substantial variation in outcomes among US hospitals.

OBJECTIVE

To update and validate the NRN extremely preterm birth outcome model for most extremely preterm infants in the United States.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study included 3 observational cohorts from January 1, 2006, to December 31, 2016, at 19 US centers in the NRN (derivation cohort) and 637 US centers in Vermont Oxford Network (VON) (validation cohorts). Actively treated infants born at 22 weeks' 0 days' to 25 weeks' 6 days' gestation and weighing 401 to 1000 g, including 4176 in the NRN for 2006 to 2012, 45 179 in VON for 2006 to 2012, and 25 969 in VON for 2013 to 2016, were studied. VON cohorts comprised more than 85% of eligible US births. Data analysis was performed from May 1, 2017, to March 31, 2019.

EXPOSURES

Predictive variables used in the original model, including infant sex, birth weight, plurality, gestational age at birth, and exposure to antenatal corticosteroids.

MAIN OUTCOMES AND MEASURES

The main outcome was death before discharge. Secondary outcomes included neurodevelopmental impairment at 18 to 26 months' corrected age and measures of hospital resource use (days of hospitalization and ventilator use).

RESULTS

Among 4176 actively treated infants in the NRN cohort (48% female; mean [SD] gestational age, 24.2 [0.8] weeks), survival was 63% vs 62% among 3702 infants in the era of the original model (47% female; mean [SD] gestational age, 24.2 [0.8] weeks). In the concurrent (2006-2012) VON cohort, survival was 66% among 45 179 actively treated infants (47% female; mean [SD] gestational age, 24.1 [0.8] weeks) and 70% among 25 969 infants from 2013 to 2016 (48% female; mean [SD] gestational age, 24.1 [0.8] weeks). Model C statistics were 0.74 in the 2006-2012 validation cohort and 0.73 in the 2013-2016 validation cohort. With the use of decision curve analysis to compare the model with a gestational age-only approach to prognostication, the updated model showed a predictive advantage. The birth hospital contributed equally as much to prediction of survival as gestational age (20%) but less than the other factors combined (60%).

CONCLUSIONS AND RELEVANCE

An updated model using well-known factors to predict survival for extremely preterm infants performed moderately well when applied to large US cohorts. Because survival rates change over time, the model requires periodic updating. The hospital of birth contributed substantially to outcome prediction.