In 2009, the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) invited an expert panel to a workshop to address the current knowledge gaps and lack of evidence-based guidelines that preclude optimal nutritional care for infants in neonatal intensive care units. Since much research needs to be done in this complex area of science, the group was requested to propose new research to rectify current deficiencies in this field. This paper provides a summary of the workshop presentations and discussions.
prematurity; preterm infants; intensive care; infant; nutrition
Perinatal brain injury; cerebral palsy; resuscitation; hypothermia; hypoxic-ischemic encephalopathy; biomarker
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.
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.
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.
MRI; neurodevelopmental; neuroimaging; preterm infant; ultrasound
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).
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.
antenatal magnesium; nasal CPAP; neonatal resuscitation; preterm infants
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.
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.
blood pressure; cardiovascular insufficiency; outcomes; newborn; infant
Hypothermia for hypoxic ischemic encephalopathy has recently permeated clinical practice for term infants. Speculation regarding a neuroprotective benefit of hypothermia for premature infants with HIE has been raised as a need for further research. Hypothermia for other indications including necrotizing enterocolitis with the hope of tissue preservation following injury is less well studied. A summary of evidence for hypothermia and premature infants is presented in this brief report.
Infant; premature; hypoxic-ischemic encephalopathy; hypothermia; necrotizing enterocolitis
A panel of experts convened by the Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, developed proposed guidelines for the evaluation of adverse events in newborns of women participating in clinical trials of maternal immunization in the United States.
maternal immunization; safety; pregnancy; vaccines; clinical trials
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.
For newborn infants in intensive care units, the morbidity and mortality from infection continues to be a major burden despite advances in neonatal care. Infants are at risk for early onset, late onset, as well as hospital acquired infections. Research studies are needed to optimize timely diagnosis and treatment, and develop patient-specific and system-wide strategies to prevent perinatal and neonatal infections. To address the knowledge gaps that preclude optimal, evidence-based care in this critical field, the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) organized a workshop in August 2008. In this paper we provide a summary of the discussions, focusing on major knowledge gaps, and prioritized suggestions for research in this area.
infant; infection; newborn; sepsis
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.)
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.
indomethacin; intestinal perforation; necrotizing enterocolitis; neonate
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.
Hypoxic ischemic encephalopathy is a serious condition affecting infants which can result in death and disability. This is a summary of pathogenesis of HIE, animal studies of cooling for hypoxic and ischemic models, human hypothermia trials, and the American Academy of Pediatrics publication on hypothermia for HIE. Hypothermia for neonatal HIE is continuing to evolve as a therapy. Studies, gaps in knowledge and opportunities for research are presented herein.
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).
MAIN OUTCOME MEASURES
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.
CONCLUSIONS AND RELEVANCE
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.
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.
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.
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
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.)
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.
DESIGN, SETTING, AND PARTICIPANTS
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.
MAIN OUTCOMES AND MEASURES
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%.
CONCLUSIONS AND RELEVANCE
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.
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.
Inhaled nitric oxide; bronchopulmonary dysplasia; extremely premature infant
Little is known about how very low birth weight (VLBW) affects survival and morbidities among infants with trisomy 13 (T13) or trisomy 18 (T18). We examined the care plans for VLBW infants with T13 or T18 and compared their risks of mortality and neonatal morbidities with VLBW infants with trisomy 21 and VLBW infants without birth defects.
Infants with birth weight 401 to 1500 g born or cared for at a participating center of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network during the period 1994–2009 were studied. Poisson regression models were used to examine risk of death and neonatal morbidities among infants with T13 or T18.
Of 52 262 VLBW infants, 38 (0.07%) had T13 and 128 (0.24%) had T18. Intensity of care in the delivery room varied depending on whether the trisomy was diagnosed before or after birth. The plan for subsequent care for the majority of the infants was to withdraw care or to provide comfort care. Eleven percent of infants with T13 and 9% of infants with T18 survived to hospital discharge. Survivors with T13 or T18 had significantly increased risk of patent ductus arteriosus and respiratory distress syndrome compared with infants without birth defects. No infant with T13 or T18 developed necrotizing enterocolitis.
In this cohort of liveborn VLBW infants with T13 or T18, the timing of trisomy diagnosis affected the plan for care, survival was poor, and death usually occurred early.
trisomy 13; trisomy 18; trisomy 21; very low birth weight; preterm infants
Chorioamnionitis is strongly linked to preterm birth and to neonatal infection. The association between histological and clinical chorioamnionitis and cognitive, behavioral and neurodevelopmental outcomes among extremely preterm neonates is less clear. We evaluated the impact of chorioamnionitis on 18-22 month neurodevelopmental outcomes in a contemporary cohort of extremely preterm neonates.
To compare the neonatal and neurodevelopmental outcomes of three groups of extremely-low-gestational-age infants with increasing exposure to perinatal inflammation: no chorioamnionitis, histological chorioamnionitis alone, or histological plus clinical chorioamnionitis.
Longitudinal observational study.
Sixteen centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network.
2390 extremely preterm infants born <27 weeks' gestational age between January 1, 2006 and December 31, 2008 with placental histopathology and 18-22 months' corrected age follow-up data were eligible.
Main Outcome Measures
Outcomes included cerebral palsy, gross motor functional limitation, behavioral scores (according to the Brief Infant-Toddler Social and Emotional Assessment), cognitive and language scores (according to the Bayley Scales of Infant Development, 3rd-Edition) and composite measures of death/neurodevelopmental impairment. Multivariable logistic and linear regression models were developed to assess the association between chorioamnionitis and outcomes while controlling for important variables known at birth.
Neonates exposed to chorioamnionitis had a lower gestational age (GA) and had higher rates of early-onset sepsis and severe periventricular-intraventricular hemorrhage as compared with unexposed neonates. In multivariable models evaluating death and neurodevelopmental outcomes, inclusion of gestational age in the model diminished the association between chorioamnionitis and adverse outcomes. Still, histological+clinical chorioamnionitis was associated with increased risk of cognitive impairment as compared with no chorioamnionitis (Adjusted OR 2.4, [1.3- 4.3] without GA; Adjusted OR 2.0, [1.1-3.6] with GA as a covariate). Histological chorioamnionitis alone was associated with lower odds of death/neurodevelopmental impairment as compared with histological+clinical chorioamnionitis (Adjusted OR 0.68, [0.52-0.89] without GA; 0.66, [0.49-0.89] with GA). Risk of behavioral problems did not differ statistically between groups.
Conclusions and Relevance
Antenatal exposure to chorioamnionitis is associated with altered odds of cognitive impairment and death/neurodevelopmental impairment in extremely preterm infants.
chorioamnionitis; preterm; neurodevelopmental impairment; outcome
The goal was to identify cytokines associated with necrotizing enterocolitis (NEC). Based on our earlier reports of decreased tissue expression of transforming growth factor (TGF)-β, we hypothesized that infants with NEC also have low blood TGF-β levels. We further hypothesized that because fetal inflammation increases the risk of NEC, infants who develop NEC have elevated blood cytokine levels in early neonatal period.
Data on 104 extremely low birth weight (ELBW) infants with NEC and 893 without NEC from 17 centers were analyzed. Clinical information was correlated with blood cytokine levels on postnatal day 1 (D1), D3, D7, D14, and D21.
Male gender, non-Caucasian/non-African-American ethnicity, sepsis, lower blood TGF-β and interleukin (IL)-2, and higher IL-8 levels were associated with NEC. The NEC group had lower TGF-β levels than controls since D1. The diagnosis of NEC was associated with elevated IL-1β, IL-6, IL-8, IL-10, monocyte chemoattractant protein-1/CC-motif ligand (CCL)-2, macrophage inflammatory protein-1β/CCL3, and C-reactive protein.
Clinical characteristics, such as gender and ethnicity, and low blood TGF-β levels are associated with higher risk of NEC. Infants who developed NEC did not start with high blood levels of inflammatory cytokines, but these rose mainly after the onset of NEC.
To test the hypothesis that acidosis at birth is associated with the combined primary outcome of death or neurodevelopmental impairment (NDI) in extremely low birth weight (ELBW) infants, and to develop a predictive model of death/NDI exploring perinatal acidosis as a predictor variable.
The study population consisted of ELBW infants born between 2002-2007 at NICHD Neonatal Research Network hospitals. Infants with cord blood gas data and documentation of either mortality prior to discharge or 18-22 month neurodevelopmental outcomes were included. Multiple logistic regression analysis was used to determine the contribution of perinatal acidosis, defined as a cord blood gas with a pH<7 or base excess (BE)<-12, to death/NDI in ELBW infants. In addition, a multivariable model predicting death/NDI was developed.
3979 patients were identified of whom 249 had a cord gas pH<7 or BE<-12 mEq/L. 2124 patients (53%) had the primary outcome of death/NDI. After adjustment for confounding variables, pH<7 and BE<-12 mEq/L were each significantly associated with death/NDI (OR=2.5[1.6,4.2]; and OR=1.5[1.1,2.0], respectively). However, inclusion of pH or BE did not improve the ability of the multivariable model to predict death/NDI.
Perinatal acidosis is significantly associated with death/NDI in ELBW infants. Perinatal acidosis is infrequent in ELBW infants, however, and other factors are more important in predicting death/NDI.
Cord blood gas; Premature infant; Preterm infant; Neurodevelopmental impairment
Inhaled nitric oxide (INO), a selective pulmonary vasodilator, has revolutionized the treatment of neonatal hypoxemic respiratory failure (NHRF). However, there is lack of sustained improvement in 30 to 46% of infants. Aerosolized prostaglandins I2 (PGI2) and E1 (PGE1) have been reported to be effective selective pulmonary vasodilators. The objective of this study was to evaluate the feasibility of a randomized controlled trial (RCT) of inhaled PGE1 (IPGE1) in NHRF.
Two pilot multicenter phase II RCTs are included in this report. In the first pilot, late preterm and term neonates with NHRF, who had an oxygenation index (OI) of ≥15 and <25 on two arterial blood gases and had not previously received INO, were randomly assigned to receive two doses of IPGE1 (300 and 150 ng/kg/min) or placebo. The primary outcome was the enrollment of 50 infants in six to nine months at 10 sites. The first pilot was halted after four months for failure to enroll a single infant. The most common cause for non-enrollment was prior initiation of INO. In a re-designed second pilot, co-administration of IPGE1 and INO was permitted. Infants with suboptimal response to INO received either aerosolized saline or IPGE1 at a low (150 ng/kg/min) or high dose (300 ng/kg/min) for a maximum duration of 72 hours. The primary outcome was the recruitment of an adequate number of patients (n = 50) in a nine-month-period, with fewer than 20% protocol violations.
No infants were enrolled in the first pilot. Seven patients were enrolled in the second pilot; three in the control, two in the low-dose IPGE1, and two in the high-dose IPGE1 groups. The study was halted for recruitment futility after approximately six months as enrollment targets were not met. No serious adverse events, one minor protocol deviation and one pharmacy protocol violation were reported.
These two pilot RCTs failed to recruit adequate eligible newborns with NHRF. Complex management RCTs of novel therapies for persistent pulmonary hypertension of the newborn (PPHN) may require novel study designs and a longer period of time from study approval to commencement of enrollment.
Trial registration: ClinicalTrials.gov
Pilot one: NCT number: 00598429 registered on 10 January 2008. Last updated: 3 February 2011.
Pilot two: NCT number: 01467076 17 October 2011. Last updated: 13 February 2013.
Electronic supplementary material
The online version of this article (doi:10.1186/1745-6215-15-486) contains supplementary material, which is available to authorized users.
Hypoxemic respiratory failure; Neonatal; Pulmonary hypertension; Aerosols; Nebulizers; Prostaglandins; Clinical trial
Difficulties with executive function has been found in preterm children, resulting in difficulties with learning and school performance.
This study evaluated the relationship of early working memory as measured by object permanence items to the cognitive and language scores on the Bayley Scales-III in a cohort of children born extremely preterm.
Logistic regression models were conducted to compare object permanence scores derived from the Bayley Scales-III by race/ethnicity and maternal education, controlling for medical covariates.
Extremely preterm toddlers (526), who were part of a Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network's multi-center study, were evaluated at 18-22 months corrected age.
Object permanence scores derived from the Bayley Developmental Scales were compared by race/ethnicity and maternal education, controlling for medical covariates.
There were no significant differences in object permanence mastery and scores among the treatment groups after controlling for medical and social variables, including maternal education and race/ethnicity. Males and children with intraventricular hemorrhage, retinopathy of prematurity, and bronchopulmonary dysplasia were less likely to demonstrate object permanence mastery and had lower object permanence scores. Children who attained object permanence mastery had significantly higher Bayley Scales-III cognitive and language scores after controlling for medical and socio-economic factors.
Our measure of object permanence is free of influence from race, ethnic and socio-economic factors. Adding this simple task to current clinical practice could help detect early executive function difficulties in young children.
Working memory; prematurity; development