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author:("Das, abik")
1.  Advantages of Bayesian monitoring methods in deciding whether and when to stop a clinical trial: an example of a neonatal cooling trial 
Trials  2016;17:335.
Decisions to stop randomized trials are often based on traditional P value thresholds and are often unconvincing to clinicians. To familiarize clinical investigators with the application and advantages of Bayesian monitoring methods, we illustrate the steps of Bayesian interim analysis using a recent major trial that was stopped based on frequentist analysis of safety and futility.
We conducted Bayesian reanalysis of a factorial trial in newborn infants with hypoxic-ischemic encephalopathy that was designed to investigate whether outcomes would be improved by deeper (32 °C) or longer cooling (120 h), as compared with those achieved by standard whole body cooling (33.5 °C for 72 h). Using prior trial data, we developed neutral and enthusiastic prior probabilities for the effect on predischarge mortality, defined stopping guidelines for a clinically meaningful effect, and derived posterior probabilities for predischarge mortality.
Bayesian relative risk estimates for predischarge mortality were closer to 1.0 than were frequentist estimates. Posterior probabilities suggested increased predischarge mortality (relative risk > 1.0) for the three intervention groups; two crossed the Bayesian futility threshold.
Bayesian analysis incorporating previous trial results and different pre-existing opinions can help interpret accruing data and facilitate informed stopping decisions that are likely to be meaningful and convincing to clinicians, meta-analysts, and guideline developers.
Trial registration NCT01192776. Registered on 31 August 2010.
Electronic supplementary material
The online version of this article (doi:10.1186/s13063-016-1480-4) contains supplementary material, which is available to authorized users.
PMCID: PMC4957277  PMID: 27450203
Bayesian methods; Factorial trial; Hypothermia; Phase III trial; Stopping rules; Trial monitoring
3.  Early blood pressure, anti-hypotensive therapy and outcomes at 18 to 22 month corrected age in extremely preterm infants 
Investigate relationships between early blood pressure (BP) changes, receipt of anti-hypotensive therapy, and 18 – 22 month corrected age (CA) outcomes for extremely preterm infants.
Prospective observational study of infants 230/7 – 266/7 weeks gestational age (GA). Hourly BP values and anti-hypotensive therapy exposure in the first 24 hours were recorded. Four groups were defined: infants who did or did not receive anti-hypotensive therapy in whom BP did or did not rise at the expected rate (defined as an increase in the mean arterial BP of ≥5 mmHg/day). Random-intercept logistic modeling controlling for center clustering, GA, and illness severity was used to investigate the relationship between BP, anti-hypotensive therapies, and infant outcomes.
Sixteen academic centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network.
Main Outcome Measures
Death or neurodevelopmental impairment / developmental delay (NIDD) at 18 – 22 months CA.
Of 367 infants, 203 (55%) received an anti-hypotensive therapy, 272 (74%) survived to discharge, and 331 (90%) had a known outcome at 18 – 22 months CA. With logistic regression, there was an increased risk of death/NIDD with anti-hypotensive therapy versus no treatment (odds ratio: 1.836, 95% confidence interval: 1.092 – 3.086), but not NIDD alone (odds ratio: 1.53, 95% confidence interval: 0.708 – 3.307).
Independent of early BP changes, anti-hypotensive therapy exposure was associated with an increased risk of death/NIDD at 18 to 22 months CA when controlling for risk factors known to affect survival and neurodevelopment.
PMCID: PMC4849123  PMID: 26567120
Extremely preterm infant; blood pressure; neurodevelopment; hypotension
4.  Stopping guidelines for an effectiveness trial: what should the protocol specify? 
Trials  2016;17:240.
Despite long-standing problems in decisions to stop clinical trials, stopping guidelines are often vague or unspecified in the trial protocol. Clear, well-conceived guidelines are especially important to assist the data monitoring committees for effectiveness trials.
Main text
To specify better stopping guidelines in the protocol for such trials, the clinical investigators and trial statistician should carefully consider the following kinds of questions:How should the relative importance of the treatment benefits and hazards be assessed?For decisions to stop a trial for benefit:What would be the minimum clinically important difference for the study population?How should the probability that the benefit exceeds that difference be assessed?When should the interim analyses include data from other trials?Would the evidence meet state-of-the-art standards for treatment recommendations and practice guidelines?Should less evidence be required to stop the trial for harm than for benefit?When should conventional stopping guidelines for futility be used for comparative effectiveness trials?
Both clinical and statistical expertise are required to address such challenging questions for effectiveness trials. Their joint consideration by clinical investigators and statisticians is needed to define better stopping guidelines before starting the trial.
PMCID: PMC4862046  PMID: 27165260
Clinical trials; Effectiveness trials; Stopping guidelines; Data monitoring committees; Futility
5.  Chorioamnionitis and Culture-Confirmed Early-onset Neonatal Infections 
Pediatrics  2015;137(1):1-11.
Current guidelines for prevention of neonatal group B Streptococcal (GBS) disease recommend diagnostic evaluations and empiric antibiotic therapy for well-appearing, chorioamnionitis-exposed newborns. Some clinicians question these recommendations, citing the decline in early-onset GBS disease rates since widespread intrapartum antibiotic prophylaxis (IAP) implementation and potential antibiotic risks. We aimed to determine whether chorioamnionitis-exposed newborns with culture-confirmed early-onset infections can be asymptomatic at birth.
Multicenter, prospective surveillance for early-onset neonatal infections was conducted 2006–2009. Early-onset infection was defined as isolation of a pathogen from blood or cerebrospinal fluid collected ≤72 hours after birth. Maternal chorioamnionitis was defined by clinical diagnosis in the medical record or histologic diagnosis by placental pathology. Hospital records of newborns with early-onset infections born to mothers with chorioamnionitis were reviewed retrospectively to determine symptom onset.
Early-onset infections were diagnosed in 389 of 396,586 live births, including 232 (60%) chorioamnionitis-exposed newborns. Records for 229 were reviewed; 29 (13%) had no documented symptoms within 6 hours of birth, including 21 (9%) who remained asymptomatic at 72 hours. IAP exposure did not differ significantly between asymptomatic and symptomatic infants (76% vs. 69%, p=0.52). Assuming complete guideline implementation, we estimated 60 to 1400 newborns would receive diagnostic evaluations and antibiotics for each infected, asymptomatic newborn, depending on chorioamnionitis prevalence.
Some infants born to mothers with chorioamnionitis may have no signs of sepsis at birth despite having culture-confirmed infections. Implementation of current clinical guidelines may result in early diagnosis, but large numbers of uninfected asymptomatic infants would be treated.
PMCID: PMC4702021  PMID: 26719293
6.  Trends in Care Practices, Morbidity, and Mortality of Extremely Preterm Neonates, 1993–2012 
JAMA  2015;314(10):1039-1051.
Extremely preterm infants contribute disproportionately to neonatal morbidity and mortality.
To review 20-year trends in maternal/neonatal care, complications, and mortality among extremely preterm infants born at Neonatal Research Network centers.
Design, Setting, Participants
Prospective registry of 34,636 infants 22–28 weeks’ gestational age (GA) and 401–1500 gram birthweight born at 26 Network centers, 1993–2012.
Extremely preterm birth.
Main Outcomes
Maternal/neonatal care, morbidities, and survival. Major morbidities, reported for infants who survived more than 12 hours, were: severe necrotizing enterocolitis, infection, bronchopulmonary dysplasia, severe intracranial hemorrhage, cystic periventricular leukomalacia, and/or severe retinopathy of prematurity. Regression models assessed yearly changes, adjusting for study center, race/ethnicity, GA, birthweight for GA, and sex.
Use of antenatal corticosteroids increased from 1993 to 2012 (348/1431 [24%] to 1674/1919 [87%], p<0.001), as did cesarean delivery (625/1431 [44%] to 1227/1921 [64%], p<0.001). Delivery room intubation decreased from 1144/1433 (80%) in 1993 to 1253/1922 (65%) in 2012 (p<0.001). After increasing in the 1990s, postnatal steroid use declined to 141/1757 (8%) in 2004 (p<0.001), with no significant change thereafter. Although most infants were ventilated, continuous positive airway pressure without ventilation increased from 120/1666 (7%) in 2002 to 190/1756 (11%) in 2012 (p<0.001). Despite no improvement from 1993 to 2004, rates of late-onset sepsis declined between 2005 and 2012 for infants of each GA (median GA 26 weeks, 109/296 [37%] to 85/320 [27%], adjusted relative risk [aRR]: 0.93 [95% CI, 0.92–0.94]). Rates of other morbidities declined, but bronchopulmonary dysplasia increased between 2009 and 2012 for infants 26–27 weeks (26 weeks, 130/258 [50%] to 164/297 [55%], p<0.001). Survival increased between 2009 and 2012 for infants 23 weeks (41/152 [27%] to 50/150 [33%], aRR: 1.09 [95% CI, 1.05–1.14]) and 24 weeks (156/248 [63%] to 174/269 [65%], aRR: 1.05 [95% CI, 1.03–1.07]), with smaller relative increases for infants 25 and 27 weeks and no change for infants 22, 26 and 28 weeks. Survival without major morbidity increased approximately 2% per year for infants 25–28 weeks with no change for infants 22–24 weeks.
Conclusions and Relevance
Among extremely preterm infants born at US academic centers over the last 20 years, changes in maternal and infant care practices and modest reductions in several morbidities were observed, although bronchopulmonary dysplasia increased. Survival increased most markedly for infants born at 23 and 24 weeks and survival without major morbidity increased for infants 25–28 weeks. These findings may be valuable in counselling families and developing novel interventions.
PMCID: PMC4787615  PMID: 26348753
7.  Cognitive Outcomes After Neonatal Encephalopathy 
Pediatrics  2015;135(3):e624-e634.
To describe the spectrum of cognitive outcomes of children with and without cerebral palsy (CP) after neonatal encephalopathy, evaluate the prognostic value of early developmental testing and report on school services and additional therapies.
The participants of this study are the school-aged survivors of the National Institute of Child Health and Human Development Neonatal Research Network randomized controlled trial of whole-body hypothermia. Children underwent neurologic examinations and neurodevelopmental and cognitive testing with the Bayley Scales of Infant Development–II at 18 to 22 months and the Wechsler intelligence scales and the Neuropsychological Assessment–Developmental Neuropsychological Assessment at 6 to 7 years. Parents were interviewed about functional status and receipt of school and support services. We explored predictors of cognitive outcome by using multiple regression models.
Subnormal IQ scores were identified in more than a quarter of the children: 96% of survivors with CP had an IQ <70, 9% of children without CP had an IQ <70, and 31% had an IQ of 70 to 84. Children with a mental developmental index <70 at 18 months had, on average, an adjusted IQ at 6 to 7 years that was 42 points lower than that of those with a mental developmental index >84 (95% confidence interval, −49.3 to −35.0; P < .001). Twenty percent of children with normal IQ and 28% of those with IQ scores of 70 to 84 received special educational support services or were held back ≥1 grade level.
Cognitive impairment remains an important concern for all children with neonatal encephalopathy.
PMCID: PMC4338321  PMID: 25713280
neonatal encephalopathy; cognitive outcomes; hypoxic ischemic encephalopathy
8.  PaCO2 in Surfactant, Positive Pressure, and Oxygenation Randomized Trial (SUPPORT) 
To determine the association of PaCO2 with severe intraventricular hemorrhage (sIVH), bronchopulmonary dysplasia (BPD), and neurodevelopmental impairment (NDI) at 18–22 months in premature infants.
Secondary exploratory data analysis of SUPPORT.
Multiple referral NICUs.
1316 infants 24 0/7 to 27 6/7 weeks gestation randomized to different oxygenation (SpO2 target 85–89% vs 91–95%) and ventilation strategies.
Main Outcome Measures
Blood gases from postnatal days 0–14 were analyzed. Five PaCO2 variables were defined: minimum [Min], maximum [Max], standard deviation, average (time-weighted), and a 4 level categorical variable (hypercapnic [highest quartile of Max PaCO2], hypocapnic [lowest quartile of Min PaCO2], fluctuators [both hypercapnia and hypocapnia], and normocapnic [middle two quartiles of Max and Min PaCO2]). PaCO2 variables were compared for infants with and without sIVH, BPD, and NDI (+/− death). Multivariable logistic regression models were developed for adjusted results.
sIVH, BPD, and NDI (+/− death) were associated with hypercapnic infants and fluctuators. Association of Max PaCO2 and outcomes persisted after adjustment (Per 10 mmHg increase: sIVH/death: OR 1.27 [1.13–1.41]; BPD/death: OR 1.27 [1.12–1.44]; NDI/death: OR 1.23 [1.10–1.38], Death: OR 1.27 [1.12–1.44], all p <0.001). No interaction was found between PaCO2 category and SpO2 treatment group for sIVH/death, NDI/death, or death. Max PaCO2 was positively correlated with maximum FiO2 (rs0.55, p<0.0001) & ventilator days (rs0.61, p<0.0001).
Higher PaCO2 was an independent predictor of sIVH/death, BPD/death, and NDI/death. Further trials are needed to evaluate optimal PaCO2 targets for high risk infants.
PMCID: PMC4336211  PMID: 25425651
Infant; premature; Infant mortality; Infant; Premature; Diseases/epidemiology; Predictive value of tests; Prognosis; Intracranial hemorrhage; Blood Gas Analysis
9.  Neonatal Magnetic Resonance Imaging Pattern of Brain Injury as a Biomarker of Childhood Outcomes following a Trial of Hypothermia for Neonatal Hypoxic-Ischemic Encephalopathy 
The Journal of pediatrics  2015;167(5):987-993.e3.
To examine the ability of magnetic resonance imaging (MRI) patterns of neonatal brain injury defined by the National Institute of Child Health and Human Development Neonatal Research Network to predict death or IQ at 6–7 years of age following hypothermia for neonatal encephalopathy.
Study design
Out of 208 participants, 124 had MRI and primary outcome (death or IQ <70) data. The relationship between injury pattern and outcome was assessed.
Death or IQ <70 occurred in 4 of 50 (8%) of children with pattern 0 (normal MRI), 1 of 6 (17%) with 1A (minimal cerebral lesions), 1 of 4 (25%) with 1B (extensive cerebral lesions), 3 of 8 (38%) with 2A (basal ganglia thalamic, anterior or posterior limb of internal capsule, or watershed infarction), 32 of 49 (65%) with 2B (2A with cerebral lesions), and 7 of 7 (100%) with pattern 3 (hemispheric devastation), P < .001; this association was also seen within hypothermia and control subgroups. IQ was 90 ± 13 among the 46 children with a normal MRI and 69 ± 25 among the 50 children with an abnormal MRI. In childhood, for a normal outcome, a normal neonatal MRI had a sensitivity of 61%, specificity of 92%, a positive predictive value of 92%, and a negative predictive value of 59%; for death or IQ <70, the 2B and 3 pattern combined had a sensitivity of 81%, specificity of 78%, positive predictive value of 70%, and a negative predictive value of 87%.
The Neonatal Research Network MRI pattern of neonatal brain injury is a biomarker of neurodevelopmental outcome at 6–7 years of age.
PMCID: PMC4700815  PMID: 26387012
10.  Neuroimaging and Neurodevelopmental Outcome in Extremely Preterm Infants 
Pediatrics  2015;135(1):e32-e42.
Extremely preterm infants are at risk for neurodevelopmental impairment (NDI). Early cranial ultrasound (CUS) is usual practice, but near-term brain MRI has been reported to better predict outcomes. We prospectively evaluated MRI white matter abnormality (WMA) and cerebellar lesions, and serial CUS adverse findings as predictors of outcomes at 18 to 22 months’ corrected age.
Early and late CUS, and brain MRI were read by masked central readers, in a large cohort (n = 480) of infants <28 weeks’ gestation surviving to near term in the Neonatal Research Network. Outcomes included NDI or death after neuroimaging, and significant gross motor impairment or death, with NDI defined as cognitive composite score <70, significant gross motor impairment, and severe hearing or visual impairment. Multivariable models evaluated the relative predictive value of neuroimaging while controlling for other factors.
Of 480 infants, 15 died and 20 were lost. Increasing severity of WMA and significant cerebellar lesions on MRI were associated with adverse outcomes. Cerebellar lesions were rarely identified by CUS. In full multivariable models, both late CUS and MRI, but not early CUS, remained independently associated with NDI or death (MRI cerebellar lesions: odds ratio, 3.0 [95% confidence interval: 1.3–6.8]; late CUS: odds ratio, 9.8 [95% confidence interval: 2.8–35]), and significant gross motor impairment or death. In models that did not include late CUS, MRI moderate-severe WMA was independently associated with adverse outcomes.
Both late CUS and near-term MRI abnormalities were associated with outcomes, independent of early CUS and other factors, underscoring the relative prognostic value of near-term neuroimaging.
PMCID: PMC4279063  PMID: 25554820
MRI; neurodevelopmental; neuroimaging; preterm infant; ultrasound
11.  Antenatal Magnesium Sulfate Exposure and Acute Cardiorespiratory Events in Preterm Infants 
Antenatal magnesium (anteMg) is used for tocolysis, pregnancy-induced hypertension (PIH) and neuroprotection for preterm birth. Infants exposed to anteMg are at risk for respiratory depression and resuscitation in the delivery room (DR). The study objective was to compare the risk of acute cardio-respiratory (CR) events among preterm infants exposed to anteMg and those unexposed (noMg).
Study Design
This was a retrospective analysis of prospective data collected in the NICHD Neonatal Research Network's Generic Database from 4/1/11 to 3/31/12. The primary outcome was DR intubation or mechanical ventilation (MV) at birth or on day 1 of life. Secondary outcomes were endotracheal MV (eMV), hypotension and other neonatal morbidities and mortality. Logistic regression analysis evaluated the risk of primary outcomes after adjustment for gestational age (GA), center, antenatal steroids (ANS) and PIH/eclampsia.
We evaluated 1,544 infants <29 weeks GA (1,091 in anteMg group and 453 in noMg group). Mothers in the anteMg group were more likely to have higher education, PIH/eclampsia and ANS; while their infants were younger in gestation and weighed less (P<0.05). The primary outcome, mortality and neonatal morbidities were similar between groups; while eMV and hypotension were significantly less among the anteMg group compared to the noMg group. AnteMg exposure was significantly associated with decreased risk of hypotension on day 1 of life and eMV on day 3 of life in the regression analysis.
Preterm infants <29 weeks GA who were exposed to anteMg did not suffer worse CR outcomes compared to those without exposure.
PMCID: PMC4275326  PMID: 25046806
antenatal magnesium; nasal CPAP; neonatal resuscitation; preterm infants
12.  Screening Cranial Imaging at Multiple Time Points Improves Cystic Periventricular Leukomalacia Detection 
American journal of perinatology  2015;32(10):973-979.
The aim of this study is to determine whether the cystic periventricular leukomalacia (cPVL) detection rate differs between imaging studies performed at different time points.
We retrospectively reviewed the prospectively collected data of 31,708 infants from the NICHD Neonatal Research Network. Inclusion criteria were infants < 1,000 g birth weight or < 29 weeks’ gestational age who had cranial imaging performed using both early criterion (cranial ultrasound [CUS] < 28 days chronological age) and late criterion (CUS, magnetic resonance imaging, or computed tomography closest to 36 weeks postmenstrual age [PMA]). We compared the frequency of cPVL diagnosed by early and late criteria.
About 664 (5.2%) of the 12,739 infants who met inclusion criteria had cPVL using either early or late criteria; 569 using the late criterion, 250 using the early criterion, and 155 patients at both times. About 95 (14.3%) of 664 cPVL cases seen on early imaging were no longer visible on repeat screening closest to 36 weeks PMA. Such disappearance of cPVL was more common in infants < 26 weeks’ gestation versus infants of 26 to 28 weeks’ gestation (18.5 vs. 11.5%; p = 0.013).
Cranial imaging at both < 28 days chronological age and closest to 36 weeks PMA improves cPVL detection, especially for more premature infants.
PMCID: PMC4697863  PMID: 25730135
cystic periventricular leukomalacia; screening cranial imaging; extremely low birth weight preterm infants
13.  Definitions of cardiovascular insufficiency and relation to outcomes in critically ill newborn infants 
American journal of perinatology  2015;32(11):1024-1030.
We previously reported on the overall incidence, management and outcomes in infants with cardiovascular insufficiency (CVI). However, there are limited data on the relationship of the specific different definitions of CVI to short term outcomes in term and late preterm newborn infants.
To evaluate how 4 definitions of CVI relate to short term outcomes and death.
Study Design
The previously reported study was a multicenter, prospective cohort study of 647 infants ≥ 34 weeks gestation admitted to a Neonatal Research Network (NRN) newborn intensive care unit (NICU) and mechanically ventilated (MV) during their first 72 hours. The relationship of five short term outcomes at discharge and 4 different definitions of CVI were further analyzed.
All 4 definitions were associated with greater number of days on MV & days on O2. The definition using a threshold blood pressure (BP) measurement alone was not associated with days to full feeding, days in the NICU or death. The definition based on treatment of CVI was associated with all outcomes including death.
The definition using a threshold BP alone was not consistently associated with adverse short term outcomes. Using only a threshold BP to determine therapy may not improve outcomes.
PMCID: PMC4689139  PMID: 25825962
blood pressure; cardiovascular insufficiency; outcomes; newborn; infant
14.  Temperature Control During Therapeutic Hypothermia for Newborn Encephalopathy Using Different Blanketrol Devices 
Therapeutic hypothermia improves the survival and neurodevelopmental outcome of infants with newborn encephalopathy of a hypoxic-ischemic origin. The NICHD Neonatal Research Network (NRN) Whole Body Cooling trial used the Cincinnati Sub-Zero Blanketrol II to achieve therapeutic hypothermia. The Blanketrol III is now available and provides additional cooling modes that may result in better temperature control. This report is a retrospective comparison of infants undergoing hypothermia using two different cooling modes of the Blanketrol device. Infants from the NRN trial were cooled with the Blanketrol II using the Automatic control mode (B2 cohort) and were compared with infants from two new NRN centers that adopted the NRN protocol and used the Blanketrol III in a gradient mode (B3 cohort). The primary outcome was the percent time the esophageal temperature stayed between 33°C and 34°C (target 33.5°C) during maintenance of hypothermia. Cohorts had similar birth weight, gestational age, and level of encephalopathy at the initiation of therapy. Baseline esophageal temperature differed between groups (36.6°C±1.0°C for B2 vs. 33.9°C±1.2°C for B3, p<0.0001) reflecting the practice of passive cooling during transport prior to initiation of active device cooling in the B3 cohort. This difference prevented comparison of temperatures during induction of hypothermia. During maintenance of hypothermia the mean and standard deviation of the percent time between 33°C and 34°C was similar for B2 compared to B3 cohorts (94.8%±0.1% vs. 95.8%±0.1%, respectively). Both the automatic and gradient control modes of the Blanketrol devices appear comparable in maintaining esophageal temperature within the target range during maintenance of therapeutic hypothermia.
PMCID: PMC4267126  PMID: 25285767
15.  Between-Hospital Variation in Treatment and Outcomes in Extremely Preterm Infants 
The New England journal of medicine  2015;372(19):1801-1811.
Between-hospital variation in outcomes among extremely preterm infants is largely unexplained and may reflect differences in hospital practices regarding the initiation of active lifesaving treatment as compared with comfort care after birth.
We studied infants born between April 2006 and March 2011 at 24 hospitals included in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Data were collected for 4987 infants born before 27 weeks of gestation without congenital anomalies. Active treatment was defined as any potentially lifesaving intervention administered after birth. Survival and neurodevelopmental impairment at 18 to 22 months of corrected age were assessed in 4704 children (94.3%).
Overall rates of active treatment ranged from 22.1% (interquartile range [IQR], 7.7 to 100) among infants born at 22 weeks of gestation to 99.8% (IQR, 100 to 100) among those born at 26 weeks of gestation. Overall rates of survival and survival without severe impairment ranged from 5.1% (IQR, 0 to 10.6) and 3.4% (IQR, 0 to 6.9), respectively, among children born at 22 weeks of gestation to 81.4% (IQR, 78.2 to 84.0) and 75.6% (IQR, 69.5 to 80.0), respectively, among those born at 26 weeks of gestation. Hospital rates of active treatment accounted for 78% and 75% of the between-hospital variation in survival and survival without severe impairment, respectively, among children born at 22 or 23 weeks of gestation, and accounted for 22% and 16%, respectively, among those born at 24 weeks of gestation, but the rates did not account for any of the variation in outcomes among those born at 25 or 26 weeks of gestation.
Differences in hospital practices regarding the initiation of active treatment in infants born at 22, 23, or 24 weeks of gestation explain some of the between-hospital variation in survival and survival without impairment among such patients. (Funded by the National Institutes of Health.)
PMCID: PMC4465092  PMID: 25946279
16.  Prophylactic Indomethacin and Intestinal Perforation in Extremely Low Birth Weight Infants 
Pediatrics  2014;134(5):e1369-e1377.
Prophylactic indomethacin reduces severe intraventricular hemorrhage but may increase spontaneous intestinal perforation (SIP) in extremely low birth weight (ELBW) infants. Early feedings improve nutritional outcomes but may increase the risk of SIP. Despite their benefits, use of these therapies varies largely by physician preferences in part because of the concern for SIP.
This was a cohort study of 15 751 ELBW infants in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network from 1999 to 2010 who survived beyond 12 hours after birth. The risk of SIP was compared between groups of infants with and without exposure to prophylactic indomethacin and early feeding in unadjusted analyses and in analyses adjusted for center and for risks of SIP.
Among infants exposed to prophylactic indomethacin, the risk of SIP did not differ between the indomethacin/early-feeding group compared with the indomethacin/no-early-feeding group (adjusted relative risk [RR] 0.74, 95% confidence interval [CI] 0.49–1.11). The risk of SIP was lower in the indomethacin/early-feeding group compared with the no indomethacin/no-early-feeding group (adjusted RR 0.58, 95% CI 0.37–0.90, P = .0159). Among infants not exposed to indomethacin, early feeding was associated with a lower risk of SIP compared with the no early feeding group (adjusted RR 0.53, 95% CI 0.36–0.777, P = .0011).
The combined or individual use of prophylactic indomethacin and early feeding was not associated with an increased risk of SIP in ELBW infants.
PMCID: PMC4533280  PMID: 25349317
indomethacin; intestinal perforation; necrotizing enterocolitis; neonate
17.  Serial aEEG recordings in a cohort of extremely preterm infants: feasibility and safety 
Amplitude-integrated EEG (aEEG) monitoring is increasing in the neonatal population, but the safety and feasibility of performing aEEG in extremely preterm infants have not been systematically evaluated.
Inborn infants 230/7 – 286/7 weeks gestation or birth weight 401–1000 grams were eligible. Serial, six-hour aEEG recordings were obtained from first week of life until 36 weeks postmenstrual age. Adverse events were documented, and surveys evaluated the impact of the aEEGs on routine care. Success of performing aEEGs according to protocol and aEEG quality were assessed.
102 infants were enrolled, with 755 recordings performed. 83% of recordings were performed according to schedule, and 96% were without adverse event. Bedside nurses reported no interference with routine care for 89% of recordings. 92% of recordings had acceptable signal quality.
Serial aEEG monitoring is safe in preterm infants, with few adverse events and general acceptance by nursing staff.
PMCID: PMC4414657  PMID: 25474559
18.  Setting research priorities to improve global newborn health and prevent stillbirths by 2025 
Yoshida, Sachiyo | Martines, José | Lawn, Joy E | Wall, Stephen | Souza, Joăo Paulo | Rudan, Igor | Cousens, Simon | Aaby, Peter | Adam, Ishag | Adhikari, Ramesh Kant | Ambalavanan, Namasivayam | Arifeen, Shams EI | Aryal, Dhana Raj | Asiruddin, Sk | Baqui, Abdullah | Barros, Aluisio JD | Benn, Christine S | Bhandari, Vineet | Bhatnagar, Shinjini | Bhattacharya, Sohinee | Bhutta, Zulfiqar A | Black, Robert E | Blencowe, Hannah | Bose, Carl | Brown, Justin | Bührer, Christoph | Carlo, Wally | Cecatti, Jose Guilherme | Cheung, Po–Yin | Clark, Robert | Colbourn, Tim | Conde–Agudelo, Agustin | Corbett, Erica | Czeizel, Andrew E | Das, Abhik | Day, Louise Tina | Deal, Carolyn | Deorari, Ashok | Dilmen, Uğur | English, Mike | Engmann, Cyril | Esamai, Fabian | Fall, Caroline | Ferriero, Donna M | Gisore, Peter | Hazir, Tabish | Higgins, Rosemary D | Homer, Caroline SE | Hoque, DE | Irgens, Lorentz | Islam, MT | de Graft–Johnson, Joseph | Joshua, Martias Alice | Keenan, William | Khatoon, Soofia | Kieler, Helle | Kramer, Michael S | Lackritz, Eve M | Lavender, Tina | Lawintono, Laurensia | Luhanga, Richard | Marsh, David | McMillan, Douglas | McNamara, Patrick J | Mol, Ben Willem J | Molyneux, Elizabeth | Mukasa, G. K | Mutabazi, Miriam | Nacul, Luis Carlos | Nakakeeto, Margaret | Narayanan, Indira | Olusanya, Bolajoko | Osrin, David | Paul, Vinod | Poets, Christian | Reddy, Uma M | Santosham, Mathuram | Sayed, Rubayet | Schlabritz–Loutsevitch, Natalia E | Singhal, Nalini | Smith, Mary Alice | Smith, Peter G | Soofi, Sajid | Spong, Catherine Y | Sultana, Shahin | Tshefu, Antoinette | van Bel, Frank | Gray, Lauren Vestewig | Waiswa, Peter | Wang, Wei | Williams, Sarah LA | Wright, Linda | Zaidi, Anita | Zhang, Yanfeng | Zhong, Nanbert | Zuniga, Isabel | Bahl, Rajiv
Journal of Global Health  null;6(1):010508.
In 2013, an estimated 2.8 million newborns died and 2.7 million were stillborn. A much greater number suffer from long term impairment associated with preterm birth, intrauterine growth restriction, congenital anomalies, and perinatal or infectious causes. With the approaching deadline for the achievement of the Millennium Development Goals (MDGs) in 2015, there was a need to set the new research priorities on newborns and stillbirth with a focus not only on survival but also on health, growth and development. We therefore carried out a systematic exercise to set newborn health research priorities for 2013–2025.
We used adapted Child Health and Nutrition Research Initiative (CHNRI) methods for this prioritization exercise. We identified and approached the 200 most productive researchers and 400 program experts, and 132 of them submitted research questions online. These were collated into a set of 205 research questions, sent for scoring to the 600 identified experts, and were assessed and scored by 91 experts.
Nine out of top ten identified priorities were in the domain of research on improving delivery of known interventions, with simplified neonatal resuscitation program and clinical algorithms and improved skills of community health workers leading the list. The top 10 priorities in the domain of development were led by ideas on improved Kangaroo Mother Care at community level, how to improve the accuracy of diagnosis by community health workers, and perinatal audits. The 10 leading priorities for discovery research focused on stable surfactant with novel modes of administration for preterm babies, ability to diagnose fetal distress and novel tocolytic agents to delay or stop preterm labour.
These findings will assist both donors and researchers in supporting and conducting research to close the knowledge gaps for reducing neonatal mortality, morbidity and long term impairment. WHO, SNL and other partners will work to generate interest among key national stakeholders, governments, NGOs, and research institutes in these priorities, while encouraging research funders to support them. We will track research funding, relevant requests for proposals and trial registers to monitor if the priorities identified by this exercise are being addressed.
PMCID: PMC4576458  PMID: 26401272
19.  Surgery and Neurodevelopmental Outcome of Very Low Birth Weight Infants 
JAMA pediatrics  2014;168(8):746-754.
Reduced death and neurodevelopmental impairment among infants is a goal of perinatal medicine.
To assess the association between surgery during the initial hospitalization and death or neurodevelopmental impairment of very low birth weight infants.
Retrospective cohort analysis of patients enrolled in the National Institute of Child Health and Human Development Neonatal Research Network Generic Database from 1998–2009 and evaluated at 18–22 months’ corrected age.
22 academic neonatal intensive care units.
Inclusion criteria were: birth weight 401–1500 g; survival to 12 hours; available for follow-up. Some conditions were excluded. 12 111 infants were included in analyses, 87% of those eligible.
Surgical procedures; surgery also classified by expected anesthesia type as major (general anesthesia) or minor surgery (non-general anesthesia).
Multivariable logistic regression analyses planned a priori were performed for the primary outcome of death or neurodevelopmental impairment and for the secondary outcome of neurodevelopmental impairment among survivors. Multivariable linear regression analyses were performed as planned for the adjusted means of Bayley Scales of Infant Development, Second Edition, Mental Developmental Index and Psychomotor Developmental Index for patients born before 2006.
There were 2186 major, 784 minor and 9141 no surgery patients. The risk-adjusted odds ratio of death or neurodevelopmental impairment for all surgery patients compared with those who had no surgery was 1.29 (95% confidence interval 1.08–1.55). For patients who had major surgery compared with those who had no surgery the risk-adjusted odds ratio of death or neurodevelopmental impairment was 1.52 (95% confidence interval 1.24–1.87). Patients classified as having minor surgery had no increased adjusted risk. Among survivors who had major surgery compared with those who had no surgery the adjusted odds ratio for neurodevelopmental impairment was 1.56 (95% confidence interval 1.26–1.93) and the adjusted mean Mental Developmental Index and mean Psychomotor Developmental Index values were lower.
Major surgery in very low birth weight infants is independently associated with a greater than 50% increased risk of death or neurodevelopmental impairment and of neurodevelopmental impairment at 18–22 months’ corrected age. The role of general anesthesia is implicated but remains unproven.
PMCID: PMC4142429  PMID: 24934607
20.  Respiratory Outcomes of the Surfactant Positive Pressure and Oximetry Randomized Trial 
The Journal of pediatrics  2014;165(2):240-249.e4.
To explore the early childhood pulmonary outcomes of infants who participated in the NICHD SUPPORT Trial, using a factorial design that randomized extremely preterm infants to lower vs. higher oxygen saturation targets and delivery room CPAP vs. intubation/surfactant, found no significant difference in the primary composite outcome of death or BPD.
Study design
The Breathing Outcomes Study, a prospective secondary to SUPPORT, assessed respiratory morbidity at 6 month intervals from hospital discharge to 18–22 months corrected age (CA). Two pre-specified primary outcomes, wheezing more than twice per week during the worst 2 week period and cough longer than 3 days without a cold were compared between each randomized intervention.
One or more interviews were completed for 918 of 922 eligible infants. The incidence of wheezing and cough were 47.9% and 31.0%, respectively, and did not differ between study arms of either randomized intervention. Infants randomized to lower vs. higher oxygen saturation targets had similar risks of death or respiratory morbidities (except for croup, treatment with oxygen or diuretics at home). Infants randomized to CPAP vs. intubation/surfactant had fewer episodes of wheezing without a cold (28.9% vs. 36.5%, p<0.05), respiratory illnesses diagnosed by a doctor (47.7% vs. 55.2%, p<0.05) and physician or emergency room visits for breathing problems (68.0% vs. 72.9%, p<0.05) by 18–22 months CA.
Treatment with early CPAP rather than intubation/surfactant is associated with less respiratory morbidity by 18–22 months CA. Longitudinal assessment of pulmonary morbidity is necessary to fully evaluate the potential benefits of respiratory interventions for neonates.
PMCID: PMC4111960  PMID: 24725582
Bronchopulmonary Dysplasia; Infant, Newborn; Infant, Low Birth Weight; Infant, Extremely Low Birth Weight; Infant, Premature; Infant, Extremely Low Gestational Age; Infant mortality; Respiratory morbidity; Intensive care, neonatal; Hospital Readmission; Oximetry; Randomized controlled trial; Retinopathy of prematurity (ROP); Continuous Positive Airway Pressure; Intubation, endotracheal; Pulmonary surfactants/therapeutic use; Oxygen inhalation therapy/methods; Oxygen administration & dosage; Follow-up studies
21.  Causes and Timing of Death in Extremely Premature Infants from 2000 through 2011 
The New England journal of medicine  2015;372(4):331-340.
Understanding the causes and timing of death in extremely premature infants may guide research efforts and inform the counseling of families.
We analyzed prospectively collected data on 6075 deaths among 22,248 live births, with gestational ages of 22 0/7 to 28 6/7 weeks, among infants born in study hospitals within the National Institute of Child Health and Human Development Neonatal Research Network. We compared overall and cause-specific in-hospital mortality across three periods from 2000 through 2011, with adjustment for baseline differences.
The number of deaths per 1000 live births was 275 (95% confidence interval [CI], 264 to 285) from 2000 through 2003 and 285 (95% CI, 275 to 295) from 2004 through 2007; the number decreased to 258 (95% CI, 248 to 268) in the 2008–2011 period (P = 0.003 for the comparison across three periods). There were fewer pulmonary-related deaths attributed to the respiratory distress syndrome and bronchopulmonary dysplasia in 2008–2011 than in 2000–2003 and 2004–2007 (68 [95% CI, 63 to 74] vs. 83 [95% CI, 77 to 90] and 84 [95% CI, 78 to 90] per 1000 live births, respectively; P = 0.002). Similarly, in 2008–2011, as compared with 2000–2003, there were decreases in deaths attributed to immaturity (P = 0.05) and deaths complicated by infection (P = 0.04) or central nervous system injury (P<0.001); however, there were increases in deaths attributed to necrotizing enterocolitis (30 [95% CI, 27 to 34] vs. 23 [95% CI, 20 to 27], P = 0.03). Overall, 40.4% of deaths occurred within 12 hours after birth, and 17.3% occurred after 28 days.
We found that from 2000 through 2011, overall mortality declined among extremely premature infants. Deaths related to pulmonary causes, immaturity, infection, and central nervous system injury decreased, while necrotizing enterocolitis–related deaths increased. (Funded by the National Institutes of Health.)
PMCID: PMC4349362  PMID: 25607427
22.  Developmental Outcomes of Very Preterm Infants with Tracheostomies 
The Journal of pediatrics  2014;164(6):1303-1310.e2.
To evaluate the neurodevelopmental outcomes of very preterm (<30 weeks) infants who underwent tracheostomy.
Study design
Retrospective cohort study from 16 centers of the NICHD Neonatal Research Network over 10 years (2001-2011). Infants who survived to at least 36 weeks (N=8,683), including 304 infants with tracheostomies, were studied. Primary outcome was death or neurodevelopmental impairment (NDI, a composite of one or more of: developmental delay, neurologic impairment, profound hearing loss, severe visual impairment) at a corrected age of 18-22 months. Outcomes were compared using multiple logistic regression. We assessed impact of timing, by comparing outcomes of infants who underwent tracheostomy before and after 120 days of life.
Tracheostomies were associated with all neonatal morbidities examined, and with most adverse neurodevelopmental outcomes. Death or NDI occurred in 83% of infants with tracheostomies and 40% of those without [odds ratio (OR) adjusted for center 7.0 (95%CI, 5.2-9.5)]. After adjustment for potential confounders, odds of death or NDI remained higher [OR 3.3 (95%CI, 2.4-4.6)], but odds of death alone were lower [OR 0.4 (95%CI, 0.3-0.7)], among infants with tracheostomies. Death or NDI was lower in infants who received their tracheostomies before, rather than after, 120 days of life [adjusted OR 0.5 (95%CI, 0.3-0.9)].
Tracheostomy in preterm infants is associated with adverse developmental outcomes, and cannot mitigate the significant risk associated with many complications of prematurity. These data may inform counseling about tracheostomy in this vulnerable population.
PMCID: PMC4035374  PMID: 24472229
newborn; very low birth weight infant; neurodevelopmental impairment; tracheotomy; bronchopulmonary dysplasia; prematurity
23.  Effect of Depth and Duration of Cooling on Deaths in the NICU Among Neonates With Hypoxic Ischemic Encephalopathy 
JAMA  2014;312(24):2629-2639.
Hypothermia at 33.5°C for 72 hours for neonatal hypoxic ischemic encephalopathy reduces death or disability to 44% to 55%; longer cooling and deeper cooling are neuroprotective in animal models.
To determine if longer duration cooling (120 hours), deeper cooling (32.0°C), or both are superior to cooling at 33.5°C for 72 hours in neonates who are full-term with moderate or severe hypoxic ischemic encephalopathy.
Arandomized, 2 × 2 factorial design clinical trial performed in 18 US centers in the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network between October 2010 and November 2013.
Neonates were assigned to 4 hypothermia groups; 33.5°C for 72 hours, 32.0°C for 72 hours, 33.5°C for 120 hours, and 32.0°C for 120 hours.
The primary outcome of death or disability at 18 to 22 months is ongoing. The independent data and safety monitoring committee paused the trial to evaluate safety (cardiac arrhythmia, persistent acidosis, major vessel thrombosis and bleeding, and death in the neonatal intensive care unit [NICU]) after the first 50 neonates were enrolled, then after every subsequent 25 neonates. The trial was closed for emerging safety profile and futility analysis after the eighth review with 364 neonates enrolled (of 726 planned). This report focuses on safety and NICU deaths by marginal comparisons of 72 hours’ vs 120 hours’ duration and 33.5°C depth vs 32.0°C depth (predefined secondary outcomes).
The NICU death rates were 7 of 95 neonates (7%) for the 33.5°C for 72 hours group, 13 of 90 neonates (14%) for the 32.0°C for 72 hours group, 15 of 96 neonates (16%) for the 33.5°C for 120 hours group, and 14 of 83 neonates (17%) for the 32.0°C for 120 hours group. The adjusted risk ratio (RR) for NICU deaths for the 120 hours group vs 72 hours group was 1.37 (95% CI, 0.92–2.04) and for the 32.0°C group vs 33.5°C group was 1.24 (95% CI, 0.69–2.25). Safety outcomes were similar between the 120 hours group vs 72 hours group and the 32.0°C group vs 33.5°C group, except major bleeding occurred among 1% in the 120 hours group vs 3% in the 72 hours group (RR, 0.25 [95% CI, 0.07–0.91]). Futility analysis determined that the probability of detecting a statistically significant benefit for longer cooling, deeper cooling, or both for NICU death was less than 2%.
Among neonates who were full-term with moderate or severe hypoxic ischemic encephalopathy, longer cooling, deeper cooling, or both compared with hypothermia at 33.5°C for 72 hours did not reduce NICU death. These results have implications for patient care and design of future trials.
PMCID: PMC4335311  PMID: 25536254
24.  Functional status at 18 months of age as a predictor of childhood disability after neonatal hypoxic-ischemic encephalopathy 
In children with neonatal hypoxic-ischemic encephalopathy (HIE), we examined the association between 18-month functional status by parental report and disability at 6-7 years.
Prospective observational study involving participants in the NICHD randomized controlled trial of hypothermia for HIE. Parent questionnaires-Functional Status-II (FS-II), Impact on Family (IOF) and Family Resource Scale (FRS) at 18 months were correlated with 6- to 7-year developmental assessments. Disability at 6-7 years was defined as IQ < 70, gross motor functional classification scale level III-V, bilateral blindness, deafness, or epilepsy.
Rates of severe HIE (32 vs. 15%), public insurance (73% vs. 47%) and IOF scales were higher and mean (SD) FS-II independence (I) {54 (SD 35) vs. 98 (SD 8)} and general health (GH) {87 (SD 14) vs. 98 (SD 6)} scores were significantly lower in children with disability (n=37) at 6-7 years, compared to those (n=74) without disability. FS-II I scores were significantly associated with disability (OR 0.92; 95% CI 0.87-0.97; p=0.003). On path analysis, severe HIE, greater IOF and public insurance were associated with poorer 18-month FS-II I scores, which, in turn, were associated with disability at 6 to 7 years.
Poor independent functioning by parental report at 18 months in children with HIE was associated with childhood disability.
PMCID: PMC4324462  PMID: 24957482
25.  Inhaled Nitric Oxide Usage in Preterm Infants in the NICHD Neonatal Research Network: Inter-site Variation and Propensity Evaluation 
The use of inhaled nitric oxide (iNO) in preterm infants remains controversial. In October 2010, an NIH consensus development conference cautioned against use of iNO in preterm infants.
1) To determine prevalence and variability in use of iNO in the NICHD Neonatal Research Network (NRN) before and after the consensus conference and 2) separately, to examine associations between iNO use and severe BPD or death.
The NICHD NRN Generic Database collects data including iNO use on very preterm infants. A total of 13 centers contributed data across the time period 2008–2011. Infants exposed or not to iNO were compared using logistic regression, which included factors related to risk as well as their likelihood of being exposed to iNO.
A total of 4,885 infants were assessed between 2008–2011; 128 (2.6%) received iNO before Day 7, 140 (2.9%) between Day 7 and 28 and 47 (1.0%) at >28 days. Center-specific iNO use during 2008–2010 ranged from 21.9% to 0.4%; 12 of 13 sites reduced usage and overall NRN iNO usage decreased from 4.6% to 1.6% (p<0.001) in 2011. Use of iNO started between Day 7 and Day 14 was more prevalent among younger infants with more severe courses in Week 1 and associated with increased risk of severe BPD or death (OR 2.24;95% CI 1.23–4.07).
The variability and total use of iNO decreased in 2011 compared to 2008–2010. iNO administration started at ≥Day 7 was associated with more severe outcomes compared to infants without iNO exposure.
PMCID: PMC4323079  PMID: 24901452
Inhaled nitric oxide; bronchopulmonary dysplasia; extremely premature infant

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