Prenatal predictors of mortality in very preterm infants cared for in the Australian and New Zealand Neonatal Network

Hypertensive Disorders of Pregnancy and Risk of Early Brain Abnormalities on Magnetic Resonance Imaging at Term among Infants Born at ≤32 Weeks' Gestational Age

OBJECTIVE

To evaluate the proximal effects of hypertensive disorders of pregnancy (HDP) on a validated measure of brain abnormalities in infants born at ≤32 weeks' gestational age (GA) using magnetic resonance imaging at term-equivalent age.

STUDY DESIGN

In a multisite prospective cohort study, 395 infants born at ≤32 weeks' GA, underwent 3T magnetic resonance imaging scan between 39 and 44 weeks' postmenstrual age. A single neuroradiologist, blinded to clinical history, evaluated the standardized Kidokoro global brain abnormality score as the primary outcome. We classified infants as HDP-exposed by maternal diagnosis of chronic hypertension, gestational hypertension, pre-eclampsia, or eclampsia. Linear regression analysis identified the independent effects of HDP on infant brain abnormalities, adjusting for histologic chorioamnionitis, maternal smoking, antenatal steroids, magnesium sulfate, and infant sex. Mediation analyses quantified the indirect effect of HDP mediated via impaired intrauterine growth and prematurity and remaining direct effects on brain abnormalities.

RESULTS

A total of 170/395 infants (43%) were HDP-exposed. Adjusted multivariable analyses revealed HDP-exposed infants had 27% (95% CI 5%-53%) higher brain abnormality scores than those without HDP exposure (P = .02), primarily driven by increased white matter injury/abnormality scores (P = .01). Mediation analyses showed HDP-induced impaired intrauterine growth significantly (P = .02) contributed to brain abnormality scores (22% of the total effect).

CONCLUSIONS

Maternal hypertension independently increased the risk for early brain injury and/or maturational delays in infants born at ≤32 weeks' GA with an indirect effect of 22% resulting from impaired intrauterine growth. Enhanced prevention/treatment of maternal hypertension may mitigate the risk of infant brain abnormalities and potential neurodevelopmental impairments.

Outcomes of singleton preterm very low birth weight infants born to mothers with pregnancy-induced hypertension

The association between maternal pregnancy-induced hypertension (PIH) and neonatal mortality and morbidities in preterm infants has not been consistent. This study aimed to evaluate the influence of maternal PIH on mortality and morbidities in singleton infants with very low birth weight born before 30 weeks of gestational age using the Korean Neonatal Network (KNN) database. A total of 5340 singleton infants with very low birth weight were registered in the KNN registry, who were born at 23⁺⁰ to 29⁺⁶ weeks of gestational age between January 2015 and December 2020. Baseline characteristics and neonatal mortality and morbidities were compared between infants with PIH and non-PIH mothers. After adjustment for potential confounders, infants with PIH mothers had significantly higher odds of respiratory distress syndrome (OR 1.983; 95% CI 1.285-3.061, p = 0.002) and bronchopulmonary dysplasia (OR 1.458; 95% CI 1.190-1.785, p < 0.001), and severe bronchopulmonary dysplasia (OR 1.411; 95% CI 1.163-1.713, p < 0.001) than infants with non-PIH mothers, while there were no significant differences in severe intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity, or death during neonatal intensive care unit admission between infants with PIH and non-PIH mothers. This study showed that preterm infants with PIH mothers had an increased risk of neonatal respiratory morbidities, including respiratory distress syndrome and bronchopulmonary dysplasia.

Determinants of neonatal mortality among preterm births in Black Lion Specialized Hospital, Addis Ababa, Ethiopia: a case-cohort study

BACKGROUND

Preterm neonatal death is a global burden in both developed and developing countries. In Ethiopia, it is the first and fourth cause of newborn and under-5 deaths, respectively. From 2015 to present, the government of Ethiopia showed its effort to improve the survival of neonates, mainly preterm births, through the inclusion of high-impact life-saving neonatal interventions. Despite these efforts, the cause of preterm neonatal death is still not reduced as expected. Therefore, this study aimed to identify determinants of preterm neonatal mortality.

METHODS

An institution-based retrospective case-cohort study was conducted among a cohort of preterm neonates who were born between March 2013 and February 2018. A total of 170 cases were considered when the neonates died during the retrospective follow-up period, which was confirmed by reviewing a medical death certificate. Controls were 404 randomly selected charts of neonates who survived the neonatal period. Data were collected from patient charts using a data extraction tool, entered using EpiData V.3.1 and analysed using STATA V.14. Finally, a multivariate logistic regression analysis was performed, and goodness of fit of the final model was tested using the likelihood ratio test. Statistical significance was declared at a p value of ≤0.05.

RESULTS

In this study, the overall incidence rate of mortality was 39.1 (95% CI: 33.6 to 45.4) per 1000 neonate-days. Maternal diabetes mellitus (adjusted OR (AOR): 2.3 (95% CI: 1.4 to 3.6)), neonatal sepsis (AOR: 1.6 (95% CI: 1.1 to 2.4)), respiratory distress (AOR: 1.5 (95% CI: 1.1 to 2.3)), extreme prematurity (AOR: 2.9 (95% CI: 1.61 to 5.11)), low Apgar score (AOR: 3.1 (95% CI: 1.79 to 5.05)) and premature rupture of membranes (AOR: 2.3 (95% CI: 1.8 to 3.5)) were found to be predictors.

CONCLUSION

In this study, the overall incidence was found to be high. Premature rupture of membranes, maternal diabetes mellitus, sepsis, respiratory distress, extreme prematurity and low Apgar score were found to be predictors of neonatal mortality. Therefore, it should be better to give special attention to patients with significantly associated factors.

Prognostic Models Predicting Mortality in Preterm Infants: Systematic Review and Meta-analysis

CONTEXT

Prediction models can be a valuable tool in performing risk assessment of mortality in preterm infants.

OBJECTIVE

Summarizing prognostic models for predicting mortality in very preterm infants and assessing their quality.

DATA SOURCES

Medline was searched for all articles (up to June 2020).

STUDY SELECTION

All developed or externally validated prognostic models for mortality prediction in liveborn infants born <32 weeks' gestation and/or <1500 g birth weight were included.

DATA EXTRACTION

Data were extracted by 2 independent authors. Risk of bias (ROB) and applicability assessment was performed by 2 independent authors using Prediction model Risk of Bias Assessment Tool.

RESULTS

One hundred forty-two models from 35 studies reporting on model development and 112 models from 33 studies reporting on external validation were included. ROB assessment revealed high ROB in the majority of the models, most often because of inadequate (reporting of) analysis. Internal and external validation was lacking in 41% and 96% of these models. Meta-analyses revealed an average C-statistic of 0.88 (95% confidence interval [CI]: 0.83-0.91) for the Clinical Risk Index for Babies score, 0.87 (95% CI: 0.81-0.92) for the Clinical Risk Index for Babies II score, and 0.86 (95% CI: 0.78-0.92) for the Score for Neonatal Acute Physiology Perinatal Extension II score.

LIMITATIONS

Occasionally, an external validation study was included, but not the development study, because studies developed in the presurfactant era or general NICU population were excluded.

CONCLUSIONS

Instead of developing additional mortality prediction models for preterm infants, the emphasis should be shifted toward external validation and consecutive adaption of the existing prediction models.

Short Term Outcome and Predictors of Mortality Among Very Low Birth Weight Infants - A Descriptive Study

OBJECTIVE

To assess the short term outcome and predictors of mortality among very low birth weight (VLBW) neonates.

METHODS

This descriptive study from a tertiary care teaching institute in south India included 239 VLBW neonates who were uniformly managed as per unit's protocol and followed up till discharge or death, whichever was earlier. Univariate analysis and logistic regression analysis were done to determine the predictors of mortality. Two logistic regression models were developed and to evaluate their discriminative performance, area under the receiver operating characteristic curves were calculated.

RESULTS

Mean gestational age and mean birth weight of neonates were 31.4 ± 3 wk and 1191 ± 245 g respectively. Among the 239 infants, 49 (20.5%) expired and 190 (70.5%) survived. Mortality among extremely low birth weight (ELBW) and extreme preterm infants were 69.3% and 73.3% respectively. Univariate analysis showed multiple perinatal factors and neonatal morbidities were associated with mortality. On adjusted multivariate logistic regression, birth weight < 1000 g (OR 9.27), severe grade of intraventricular hemorrhage (IVH) (OR 29.2), hyperglycemia (OR 7.8) and respiratory distress syndrome (RDS) requiring surfactant therapy (OR 6.2) were the significant predictors of mortality. Both logistic regression models developed showed good prediction of mortality.

CONCLUSIONS

VLBW mortality rate is 20% in the population studied. Birth weight < 1000 g, severe grade of IVH, hyperglycemia, and RDS requiring surfactant therapy were the significant predictors of mortality among VLBW neonates. Both prediction models developed showed good prediction of mortality.

Do preterm girls need different nutrition to preterm boys? Sex-specific nutrition for the preterm infant

Boys born preterm are recognised to be at higher risk of adverse outcomes than girls born preterm. Despite advances in neonatal intensive care and overall improvements in neonatal morbidity and mortality, boys born preterm continue to show worse short- and long-term outcomes than girls. Preterm birth presents a nutritional crisis during a critical developmental period, with postnatal undernutrition and growth-faltering common complications of neonatal intensive care. Furthermore, this preterm period corresponds to that of rapid in utero brain growth and development, and the developmental window relating to foetal programming of adult non-communicable diseases, the prevalence of which are associated both with preterm birth and sex. There is increasing evidence to show that from foetal life, boys and girls have different responses to maternal nutrition, that maternal breastmilk composition differs based on foetal sex and that early neonatal nutritional interventions affect boys and girls differently. This narrative review examines the evidence that sex is an important moderator of the outcomes of preterm nutrition intervention, and describes what further knowledge is required before providing nutrition intervention for infants born preterm based on their sex. IMPACT: This review examines the increasing evidence that boys and girls respond differently to nutritional stressors before birth, that maternal breastmilk composition differs by foetal sex and that nutritional interventions have different responses based on infant sex. Boys and girls born preterm are given standard nutritional support which does not take infant sex into account, and few studies of neonatal nutrition consider infant sex as a potential mediator of outcomes. By optimising early nutrition for boys and girls born preterm, we may improve outcomes for both sexes. We propose future studies of neonatal nutritional interventions should consider infant sex.

Factors Associated with the Death of Preterm Babies Admitted to Neonatal Intensive Care Units in Ethiopia: A Prospective, Cross-sectional, and Observational Study

Aim. To determine the risk factors for death among preterm neonates. Methods and materials. The data set used was derived from a prospective, multi-center, observational clinical study conducted in 5 tertiary hospitals in Ethiopia from July, 2016 to May, 2018. Subjects were infants admitted into neonatal intensive care unit. Results. Risk factors were determined using statistical model developed for this study. The mean gestational age was 32.87 (SD ± 2.42) weeks with a range of 20 to 36 weeks. There were 2667 (70.69%) survivors and 1106 (29.31%) deaths. The significant risk factors for preterm death were low gestational age, low birth weight, being female, feeding problem, no antenatal care visits and vaginal delivery among mothers with higher educational level. Conclusions. The study identified several risk factors for death among preterm neonates. Most of the risk factors are preventable. Thus, it is important to address neonatal and maternal factors identified in this study through appropriate ANC and optimum infant medical care and feeding practices to decrease the high rate of preterm death.

A need for an update of Polish birth weight reference norms

The indicators of perinatal outcome are birth weight and gestational age. The standard method of assessing the outcome is comparing the newborn’s birth weight with the reference system, presented in the form of percentile charts. Acceleration or delay in prenatal development, which are associated with environmental changes, stress the need to validate the developmental norms. The goal of this study is to evaluate the need to construct new and accurate reference standards. The study includes data of newborns from singleton pregnancies: 4919 born in 2000 and 3683 born in 2015. Study variables included gestational age, sex, and birth weight. Percentile values estimated for two groups of infants born in years separated by a 15-year period, born in 2000 and in 2015, were compared. Birth weight percentiles, from the 28th to the 42nd week of gestation, were calculated using the Lambda Mu Sigma method. Estimated values revealed the birth weight standards in different weeks of gestational age for both years: 2000 and 2015. Comparison among medians estimated for infants born in these years showed the existence of significant differences among boys in the 28th, 36th, and 39th weeks and among girls in the 34th and 41st weeks of gestational age. As the period between the two measurements involves several years, environmental changes during this time period might have significantly affected the course of pregnancy and thus the birth weight. Hence, there is a need to validate the developmental norms. The reference standards should be renewed, and must be done on a periodical basis.

Lung Function of Adults Born at Very Low Birth Weight

BACKGROUND

Much remains unknown about the consequences of very low birth weight (VLBW) and bronchopulmonary dysplasia (BPD) on adult lungs. We hypothesized that VLBW adults would have impaired lung function compared with controls, and those with a history of BPD would have worse lung function than those without.

METHODS

At age 26 to 30 years, 226 VLBW survivors of the New Zealand VLBW cohort and 100 term controls born in 1986 underwent lung function tests including spirometry, plethysmographic lung volumes, diffusing capacity of the lung for carbon monoxide, and single-breath nitrogen washout (SBN₂).

RESULTS

An obstructive spirometry pattern was identified in 35% VLBW subjects versus 14% controls, with the majority showing mild obstruction. Compared with controls, VLBW survivors demonstrated significantly lower forced expiratory volume in 1 second (FEV₁), FEV₁/forced vital capacity (FVC) ratio (FEV₁/FVC), forced expiratory flow at 25% to 75% of FVC and higher residual volume (RV), RV/total lung capacity (TLC) ratio (RV/TLC), decreased diffusing capacity of the lung for carbon monoxide, and increased phase III slope for SBN₂. The differences persisted after adjustment for sex and smoking status. Within the VLBW group, subjects with BPD showed significant reduction in FEV₁, FEV₁/FVC, and forced expiratory flow at 25% to 75% of FVC, and increase in RV, RV/TLC, and phase III slope for SBN₂, versus subjects without. The differences remained after adjustment for confounders.

CONCLUSIONS

Adult VLBW survivors showed a higher incidence of airflow obstruction, gas trapping, reduced gas exchange, and increased ventilatory inhomogeneity versus controls. The findings suggest pulmonary effects due to VLBW persist into adulthood, and BPD is a further insult on small airway function.

Trends in Outcomes for Neonates Born Very Preterm and Very Low Birth Weight in 11 High-Income Countries

OBJECTIVE

To evaluate outcome trends of neonates born very preterm in 11 high-income countries participating in the International Network for Evaluating Outcomes of neonates.

STUDY DESIGN

In a retrospective cohort study, we included 154 233 neonates admitted to 529 neonatal units between January 1, 2007, and December 31, 2015, at 24^0/7 to 31^6/7 weeks of gestational age and birth weight <1500 g. Composite outcomes were in-hospital mortality or any of severe neurologic injury, treated retinopathy of prematurity, and bronchopulmonary dysplasia (BPD); and same composite outcome excluding BPD. Secondary outcomes were mortality and individual morbidities. For each country, annual outcome trends and adjusted relative risks comparing epoch 2 (2012-2015) to epoch 1 (2007-2011) were analyzed.

RESULTS

For composite outcome including BPD, the trend decreased in Canada and Israel but increased in Australia and New Zealand, Japan, Spain, Sweden, and the United Kingdom. For composite outcome excluding BPD, the trend decreased in all countries except Spain, Sweden, Tuscany, and the United Kingdom. The risk of composite outcome was lower in epoch 2 than epoch 1 in Canada (adjusted relative risks 0.78; 95% CI 0.74-0.82) only. The risk of composite outcome excluding BPD was significantly lower in epoch 2 compared with epoch 1 in Australia and New Zealand, Canada, Finland, Japan, and Switzerland. Mortality rates reduced in most countries in epoch 2. BPD rates increased significantly in all countries except Canada, Israel, Finland, and Tuscany.

CONCLUSIONS

In most countries, mortality decreased whereas BPD increased for neonates born very preterm.

Maternal hypertension and survival in singletons and twins born at 23-29 weeks: not just one answer…

BACKGROUND

To describe the association between maternal hypertension (chronic and gestational, MH) and mortality in very preterm singletons and twins, focusing on how estimates depend on gestational age (GA) and size at birth.

METHODS

We estimated relative risks of in-hospital death in 12,320 singletons (MH: 22.4%) and 4381 twins (MH: 10.6%) born at 23-29 weeks in the Italian Neonatal Network (89 hospitals, 2008-2016).

RESULTS

Babies with MH had higher GA and were more frequently small-for-gestational age (SGA), especially singletons. In crude analyses, MH was associated with lower mortality in singletons. In multivariable analyses, the effects of GA and size differed between twins and singletons with and without MH. The best-fitting models included continuous birth weight (rather than SGA) and were stratified by GA. In these models, MH was associated with lower mortality in singletons-but not twins-born after week 25.

CONCLUSIONS

In this cohort of very preterm infants, the association between MH and mortality differed between singletons and twins and across strata of GA at birth. These estimates cannot be interpreted causally, but suggest that, from a descriptive/predictive standpoint, singletons with MH born after week 25 have lower mortality than singletons born to women without MH.

Predictors of mortality for preterm infants with intraventricular hemorrhage: a population-based study

PURPOSE

The goal of this longitudinal, population-level study was to examine factors affecting mortality in preterm infants with intraventricular hemorrhage (IVH).

METHODS

The study examined patients who were born at 36 weeks estimated gestational age (EGA) or less with a diagnosis of IVH between the years 2005 and 2014 using data from the New York and Nebraska State Inpatient Databases. Potential predictors for mortality were investigated with multivariable survival analysis.

RESULTS

The cohort included 7437 preterm infants with IVH. All-cause inpatient mortality occurred in 746 (10.0%). The majority of deaths were in infants born at less than 25 weeks EGA (378 or 50.7%) and with birthweight less than 750 g (459 or 61.5%). Mortality was highest for children with grade IV IVH (306/848 or 36.1%), followed by grades III (203/955 or 21.3%), II (103/1328 or 7.8%), and I (134/4306 or 3.1%). Hydrocephalus was diagnosed within 6 months in 627 (8.4%) patients, with cerebrospinal fluid shunts required in 237 (3.2%). Shunts were eventually revised in 122 (51.5% of shunts), and 43 (18.1%) had infections. Multivariable Cox survival analyses found male sex (HR 1.3 [95% CI 1.1-1.5]), Asian race (HR 1.5 [1.1-2.2]), lower EGA (HR 9.9 [6.3-15.5] for < 25 weeks), higher IVH grade (HR 6.1 [4.9-7.6] for grade IV), gastrostomy (HR 4.0 [2.0-7.7]), tracheostomy (HR 3.5 [1.7-7.1]), and shunt infection (HR 3.2 [1.0-9.9]) to be independently associated with increased mortality risk.

CONCLUSIONS

This database is the first of its kind assembled for population-based investigations of long-term neurosurgical outcomes in preterm infants with IVH.

Microvascular circulatory dysregulation driven in part by cystathionine gamma-lyase: A new paradigm for cardiovascular compromise in the preterm newborn

OBJECTIVE

H₂ S may explain the dysregulation of microvascular tone associated with poor outcome following preterm birth. In adult vasculature, H₂ S is predominantly produced by CSE. We hypothesized that vascular CSE activity contributes to microvascular tone regulation during circulatory transition.

METHODS

Preterm (GA62) and full-term (GA69) guinea pig fetuses and neonates were studied. Microvascular blood flow was assessed by laser Doppler flowmetry. Thiosulfate, primary urinary metabolite of H₂ S, was determined by high-performance liquid chromatography. Real-time H₂ S production was assessed using a microrespiration system in fetal and postnatal (10, 24 hours) skin and heart samples. CSE contribution was investigated by inhibition via propargylglycine.

RESULTS

In preterm animals, postnatal H₂ S production capacity in peripheral vasculature increased significantly and was significantly reduced by the inhibition of CSE. Urinary thiosulfate correlated with both microvascular blood flow and capacity of the vasculature to produce H₂ S. H₂ S produced via CSE did not correlate directly with microvascular blood flow.

CONCLUSIONS

In preterm neonates, H₂ S production increases during fetal-to-neonatal transition and CSE contribution to total H₂ S increases postnatally. CSE-dependent mechanisms may therefore underpin the increase in H₂ S production over the first 72 hours of life in preterm human neonates, associated with both central and peripheral cardiovascular instability.

A framework to address key issues of neonatal service configuration in England: the NeoNet multimethods study

Background

There is an inherent tension in neonatal services between the efficiency and specialised care that comes with centralisation and the provision of local services with associated ease of access and community benefits. This study builds on previous work in South West England to address these issues at a national scale.

Objectives

(1) To develop an analytical framework to address key issues of neonatal service configuration in England, (2) to investigate visualisation tools to facilitate the communication of findings to stakeholder groups and (3) to assess parental preferences in relation to service configuration alternatives.

Main outcome measures

The ability to meet nurse staffing guidelines, volumes of units, costs, mortality, number and distance of transfers, travel distances and travel times for parents.

Design

Descriptive statistics, location analysis, mathematical modelling, discrete event simulation and economic analysis were used. Qualitative methods were used to interview policy-makers and parents. A parent advisory group supported the study.

Setting

NHS neonatal services across England.

Data

Neonatal care data were sourced from the National Neonatal Research Database. Information on neonatal units was drawn from the National Neonatal Audit Programme. Geographic and demographic data were sourced from the Office for National Statistics. Travel time data were retrieved via a geographic information system. Birth data were sourced from Hospital Episode Statistics. Parental cost data were collected via a survey.

Results

Location analysis shows that to achieve 100% of births in units with ≥ 6000 births per year, the number of birth centres would need to be reduced from 161 to approximately 72, with more parents travelling > 30 minutes. The maximum number of neonatal intensive care units (NICUs) needed to achieve 100% of very low-birthweight infants attending high-volume units is 36 with existing NICUs, or 48 if NICUs are located wherever there is currently a neonatal unit of any level. Simulation modelling further demonstrated the workforce implications of different configurations. Mortality modelling shows that the birth of very preterm infants in high-volume hospitals reduces mortality (a conservative estimate of a 1.2-percentage-point lower risk) relative to these births in other hospitals. It is currently not possible to estimate the impact of mortality for infants transferred into NICUs. Cost modelling shows that the mean length of stay following a birth in a high-volume hospital is 9 days longer and the mean cost is £5715 more than for a birth in another neonatal unit. In addition, the incremental cost per neonatal life saved is £460,887, which is comparable to other similar life-saving interventions. The analysis of parent costs identified unpaid leave entitlement, food, travel, accommodation, baby care and parking as key factors. The qualitative study suggested that central concerns were the health of the baby and mother, communication by medical teams and support for families.

Limitations

The following factors could not be modelled because of a paucity of data – morbidity outcomes, the impact of transfers and the maternity/neonatal service interface.

Conclusions

An evidence-based framework was developed to inform the configuration of neonatal services and model system performance from the perspectives of both service providers and parents.

Future work

To extend the modelling to encompass the interface between maternity and neonatal services.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Determinants of perinatal mortality among cohorts of pregnant women in three districts of North Showa zone, Oromia Region, Ethiopia: Community based nested case control study

BACKGROUND

Statistics indicate that Ethiopia has made remarkable progress in reducing child mortality. It is however estimated that there is high rate of perinatal mortality although there is scarcity of data due to a lack of vital registration in the country. This study was conducted with the purpose of assessing the determinants and causes of perinatal mortality among babies born from cohorts of pregnant women in three selected districts of North Showa Zone, Oromia Region, Ethiopia. The study used community based data, which is believed to provide more representative and reliable information and also aimed to narrow the data gap on perinatal mortality.

METHODS

A community based nested case control study was conducted among 4438 (cohorts of) pregnant women. The cohort was followed up between March 2011 to December 2012 in three districts of Oromia region, Ethiopia, until delivery. The World Health Organization verbal autopsy questionnaire for neonatal death was used to collect data. A binary logistic regression model was used to identify determinants of perinatal mortality. Causes of deaths were assigned by a pediatrician and neonatologist. Cases are stillbirths and early neonatal death. Control are live births surviving of the perinatal period' RESULT: A total of 219 newborns (73 cases and 146 controls) were included in the analysis. Perinatal mortality rate was 16.5 per 1000 births. Mothers aged 35 years and above had a higher risk of losing their newborn babies to perinatal deaths than younger mothers [AOR 7.59, (95% CI, 1.91-30.10)]. Babies born to mothers who had a history of neonatal deaths were also more likely to die during the perinatal period than their counterparts [AOR 5.42, (95% CI, 2.27-12.96)]. Preterm births had a higher risk of perinatal death than term babies [AOR 8.58, (95% CI, 2.27-32.38)]. Similarly, male babies were at higher risk than female babies [AOR 5.47, (95% CI, 2.50-11.99)]. Multiple birth babies had a higher chance of dying within the perinatal period than single births [AOR 3.59, (95% CI, 1.20-10.79)]. Home delivery [AOR 0.23, (95% CI, 0.08-0.67)] was found to reduce perinatal deaths. Asphyxia, sepsis and chorioamnionitis were among the leading causes of perinatal deaths.

CONCLUSION

This study reported a lower perinatal mortality rate. The main causes of perinatal death identified were often related to maternal factors. There is still a need for greater focus on these interrelated issues for further intervention.

Perinatal health services organization for preterm births: a multinational comparison

OBJECTIVE

To explore population characteristics, organization of health services and comparability of available information for very low birth weight or very preterm neonates born before 32 weeks' gestation in 11 high-income countries contributing data to the International Network for Evaluating Outcomes of Neonates (iNeo).

STUDY DESIGN

We obtained population characteristics from public domain sources, conducted a survey of organization of maternal and neonatal health services and evaluated the comparability of data contributed to the iNeo collaboration from Australia, Canada, Finland, Israel, Italy, Japan, New Zealand, Spain, Sweden, Switzerland and UK.

RESULTS

All countries have nationally funded maternal/neonatal health care with >90% of women receiving prenatal care. Preterm birth rate, maternal age, and neonatal and infant mortality rates were relatively similar across countries. Most (50 to >95%) between-hospital transports of neonates born at non-tertiary units were conducted by designated transport teams; 72% (8/11 countries) had designated transfer and 63% (7/11 countries) mandate the presence of a physician. The capacity of 'step-down' units varied between countries, with capacity for respiratory care available in <10% to >75% of units. Heterogeneity in data collection processes for benchmarking and quality improvement activities were identified.

CONCLUSIONS

Comparability of healthcare outcomes for very preterm low birth weight neonates between countries requires an evaluation of differences in population coverage, healthcare services and meta-data.

Evaluation of the INTERGROWTH-21st project newborn standard for use in Canada

Objective

To evaluate the performance of the INTERGROWTH-21^st Project newborn standard vis-a-vis the current Canadian birth weight-for-gestational age reference.

Methods

All hospital-based singleton live births in Canada (excluding Quebec) between 2002 and 2012 with a gestational age between 33 and 42 weeks were included using information obtained from the Canadian Institute for Health Information. Small- and large-for gestational age centile categories of the INTERGROWTH standard and Canadian reference were contrasted in terms of frequency distributions and rates of composite neonatal morbidity/mortality.

Results

Among 2,753,817 singleton live births, 0.87% and 9.63% were <3^rd centile and >97^th centile, respectively, of the INTERGROWTH standard, while 2.27% and 3.55% were <3^rd centile and >97^th centile, respectively, of the Canadian reference. Infants <3^rd centile and >97^th centile had a composite neonatal morbidity/mortality rate of 46.4 and 12.9 per 1,000 live births, respectively, under the INTERGROWTH standard and 30.9 and 16.6 per 1,000 live births, respectively, under the Canadian reference. The INTERGROWTH standard <3^rd centile and >97^th centile categories had detection rates of 3.14% and 9.74%, respectively, for composite neonatal morbidity/ mortality compared with 5.48% and 4.60%, respectively for the Canadian reference. Similar patterns were evident in high- and low-risk subpopulations.

Conclusions

The centile distribution of the INTERGROWTH newborn standard is left shifted compared with the Canadian reference, and this shift alters the frequencies and neonatal morbidity/mortality rates associated with specific centile categories. Further outcome-based research is required for defining abnormal growth categories before the INTERGROWTH newborn standard can be used.

Causes of death in very preterm infants cared for in neonatal intensive care units: a population-based retrospective cohort study

Background

While there are good data to describe changing trends in mortality and morbidity rates for preterm populations, there is very little information on the specific causes and pattern of death in terms of age of vulnerability. It is well established that mortality increases with decreasing gestational age but there are limited data on the specific causes that account for this increased mortality. The aim of this study was to establish the common causes of hospital mortality in a regional preterm population admitted to a neonatal intensive care unit (NICU).

Methods

Retrospective analysis of prospectively collected data of the Neonatal Intensive Care Units' (NICUS) Data Collection of all 10 NICUs in the region. Infants <32 weeks gestation without major congenital anomalies admitted from 2007 to 2011 were included. Three authors reviewed all cases to agree upon the immediate cause of death.

Results

There were 345 (7.7%) deaths out of 4454 infants. The most common cause of death across all gestational groups was major IVH (cause-specific mortality rate [CMR] 22 per 1000 infants), followed by acute respiratory illnesses [ARI] (CMR 21 per 1000 infants) and sepsis (CMR 12 per 1000 infants). The most common cause of death was different in each gestational group (22–25 weeks [ARI], 26–28 weeks [IVH] and 29–31 weeks [perinatal asphyxia]). Pregnancy induced hypertension, antenatal steroids and chorioamnionitis were all associated with changes in CMRs. Deaths due to ARI or major IVH were more likely to occur at an earlier age (median [quartiles] 1.4 [0.3–4.4] and 3.6 [1.9–6.6] days respectively) in comparison to NEC and miscellaneous causes (25.2 [15.4–37.3] and 25.8 [3.2–68.9] days respectively).

Conclusions

Major IVH and ARI were the most common causes of hospital mortality in this extreme to very preterm population. Perinatal factors have a significant impact on cause-specific mortality. The varying timing of death provides insight into the prolonged vulnerability for diseases such as necrotising enterocolitis in our preterm population.

The reasons why cardiologists should consider prematurity at birth and intrauterine growth retardation among risk factors

The survival percentage of infants born preterm has risen steadily worldwide thanks to the giant steps forward made in the field of perinatal (the period immediately after birth) and neonatal (the first 4 weeks of birth following delivery) medicine. However, prematurity at birth and consequent low birth weight still represent the major causes of neonatal morbidity and mortality. Infants born preterm are at high risk of developing neurological, ophthalmological, and gastrointestinal complications as well. Furthermore, extensive more recent epidemiological findings have demonstrated an increase in risk factors and a higher mortality rate due to cardiovascular causes in patients born preterm and/or with intrauterine growth restriction. The aim of this review is to provide scientific evidence about how the cardiovascular system may be negatively influenced by prematurity and by a low birth weight that should by rights be viewed as new cardiovascular risk factors. This condition is referred to as 'cardiovascular perinatal programming'. In the light of the above, an early, constant, and prolonged cardiovascular follow-up should be implemented in former preterm individuals.

[Epidemiology and risk factors of preterm birth]

OBJECTIVE

To synthesize the available evidence regarding the incidence and several risk factors of preterm birth. To describe neonatal outcomes according to gestational age and to the context of delivery.

MATERIALS AND METHODS

Consultation of the Medline database.

RESULTS

In 2010, 11% of live births (15 million babies) occurred before 37 completed weeks of gestation worldwide. About 85% of these births were moderate to late preterm babies (32-36 weeks), 10% were very preterm babies (28-31 weeks) and 5% were extremely preterm babies (<28 weeks). In France, premature birth concerns 60,000 neonates every year, 12,000 of whom are born before 32 completed weeks of gestation. Half of them are delivered after spontaneous onset of labor or preterm premature rupture of the membranes, and the other half are provider-initiated preterm births. Several maternal factors are associated with preterm birth, including sociodemographic, obstetrical, psychological, and genetic factors; paternal and environmental factors are also involved. Gestational age is highly associated with neonatal mortality and with short- and long-term morbidities. Pregnancy complications and the context of delivery also have an impact on neonatal outcomes.

CONCLUSION

Preterm birth is one of the leading cause of the under-five mortality and of neurodevelopmental impairment worldwide; it remains a major public health issue.

Predicting 2-y outcome in preterm infants using early multimodal physiological monitoring

BACKGROUND

Preterm infants are at risk of adverse outcome. The aim of this study is to develop a multimodal model, including physiological signals from the first days of life, to predict 2-y outcome in preterm infants.

METHODS

Infants <32 wk gestation had simultaneous multi-channel electroencephalography (EEG), peripheral oxygen saturation (SpO2), and heart rate (HR) monitoring. EEG grades were combined with gestational age (GA) and quantitative features of HR and SpO2 in a logistic regression model to predict outcome. Bayley Scales of Infant Development-III assessed 2-y neurodevelopmental outcome. A clinical course score, grading infants at discharge as high or low morbidity risk, was used to compare performance with the model.

RESULTS

Forty-three infants were included: 27 had good outcomes, 16 had poor outcomes or died. While performance of the model was similar to the clinical course score graded at discharge, with an area under the receiver operator characteristic (AUC) of 0.83 (95% confidence intervals (CI): 0.69-0.95) vs. 0.79 (0.66-0.90) (P = 0.633), the model was able to predict 2-y outcome days after birth.

CONCLUSION

Quantitative analysis of physiological signals, combined with GA and graded EEG, shows potential for predicting mortality or delayed neurodevelopment at 2 y of age.

An Algorithm for Predicting Neonatal Mortality in Threatened Very Preterm Birth

OBJECTIVE

To develop a prediction model for neonatal mortality using information readily available in the antenatal period.

METHODS

A multiple logistic regression model of a complete population-based geographically defined cohort of very preterm infants of 23+0 to 30+6 weeks' gestation was used to identify antenatal factors which were predictive of mortality in this population. Infants lt; 23 weeks and those with major anomalies were excluded.

RESULTS

Between 1996 and 2012, 1240 live born infants lt; 31 weeks' gestation were born to women residing in Nova Scotia. Decreasing gestational age strongly predicted an increased mortality rate. Other factors significantly contributing to increased mortality included classification as small for gestational age, oligohydramnios, maternal psychiatric disorders, antenatal antibiotic therapy, and monochorionic twins. Reduced neonatal mortality was associated with antenatal use of antihypertensive agents and use of corticosteroids of any duration of therapy given at least 24 hours before delivery. An algorithm was developed to estimate the risk of mortality without the need for a calculator.

CONCLUSION

Prediction of the probability of neonatal mortality is influenced by maternal and fetal factors. An algorithm to estimate the risk of mortality facilitates counselling and informs shared decision making regarding obstetric management.

The effect of maternal hypertension on mortality in infants 22, 29weeks gestation

OBJECTIVE

To evaluate the effect of maternal hypertension on mortality risk prior to discharge, in infants 22+0 to 29+6weeks gestational age.

STUDY DESIGN

We evaluated 88,275 North American infants whose births were recorded in Vermont Oxford Network centers between 2008 and 2011 Infants born between 22+0 and 29+6weeks gestational age were evaluated in 2-week gestational age cohorts and followed until death or discharge. Logistic regression was used to adjust for birth weight, antenatal steroid exposure, infant sex, maternal race, inborn/outborn, prenatal care and birth year.

RESULTS

21,896 infants were born to hypertensive mothers; 13% died prior to Neonatal Intensive Care Unit discharge compared to 20% of the 66,379 infants born to mothers without hypertension. After adjustment, infants had significantly lower mortality compared to preterm infants not born to hypertensive mothers, at all gestational ages examined (22/23: odds ratio (OR)=0.65 (95% Confidence Interval (CI): 0.55, 0.77; 24/25); OR=0.77 (95% CI: 0.71, 0.84); 26/27: OR=0.66 (95% CI: 0.59, 0.74); 28/29: OR=0.58 (95% CI: 0.51, 0.67). Additionally, births associated with maternal hypertension increase dramatically by gestational age, resulting in a larger proportion of births associated with maternal hypertension at later gestational ages.

CONCLUSIONS

Preterm birth due to any cause carries significant risk of mortality, especially at the earliest of viable gestational ages. Maternal hypertension independently influences mortality, with lower odds of mortality seen in infants born to hypertensive mothers, after adjustment, and should be taken into consideration as an element in counseling parents.

Risk Factors for Cause-specific Mortality of Very-Low-Birth-Weight Infants in the Korean Neonatal Network

This study attempted to assess the risk factors for mortality of very-low-birth-weight (VLBW) infants in the neonatal intensive care unit (NICU, n=2,386). Using data from the Korean Neonatal Network, we investigated infants with birth weights <1,500 g and gestational ages (GAs) of 22-31 weeks born between January 2013 and June 2014. Cases were defined as death at NICU discharge. Controls were randomly selected from live VLBW infants and frequency matched to case subjects by GA. Relevant variables were compared between the cases (n=236) and controls (n=236) by Cox proportional hazards regression to determine their associations with cause-specific mortality (cardiorespiratory, neurologic, infection, gastrointestinal, and others). In a Cox regression analysis, cardiorespiratory death were associated with a foreign mother (hazard ratio, HR, 4.33; 95% confidence interval, CI, 2.08-9.02), multiple gestation (HR, 1.65; 95% CI, 1.07-2.54), small for gestational age (HR, 2.06; 95% CI, 1.25-3.41), male gender (HR, 1.69; 95% CI, 1.10-2.60), Apgar score ≤3 at 5 min (HR, 1.97; 95% CI, 1.18-3.31), and delivery room resuscitation (HR, 2.60; 95% CI, 1.53-4.40). An Apgar score ≤3 at 5 min was also associated with neurological death (HR, 2.95; 95% CI, 1.29-6.73). Death due to neonatal infection was associated with outborn delivery (HR, 5.09; 95% CI, 1.46-17.74). Antenatal steroid and preterm premature rupture of membranes reduced risk of cardiorespiratory death (HR, 0.43; 95% CI, 0.27-0.67) and gastrointestinal death (HR, 0.30; 95% CI, 0.13-0.70), respectively. In conclusion, foreign mother, multiple gestation, small gestation age, male gender, Apgar score ≤3 at 5 min, and resuscitation in the delivery room are associated with cardiorespiratory mortality of VLBW infants in NICU. An Apgar score ≤3 at 5 min and outborn status are associated with neurological and infection mortality, respectively.

Trends in Morbidity and Mortality of Extremely Preterm Multiple Gestation Newborns

OBJECTIVES

To examine the risk of mortality and major morbidities in extremely preterm multiple gestation infants compared with singletons over time.

METHODS

This is a retrospective study of 15,402 infants born ≤27 weeks' gestation, admitted to NICUs in the Australian and New Zealand Neonatal Network from 1995 to 2009. Mortality and major morbidities were compared between singletons and multiples across three 5-year epochs.

RESULTS

Extreme preterm multiples were more likely to have lower birth weight; higher maternal age; and higher rates of assisted conception, antenatal steroid use, and cesarean delivery compared with singletons. The mortality rate was significantly higher in multiples compared with singletons even as there was a trend of decreasing gestational-age stratified mortality in multiples over the time period investigated. The rates of major morbidities or composite adverse outcomes were not different between multiples and singletons across all epochs. The adjusted odds ratio (AOR) for mortality in multiples was significantly higher in multiples compared with singletons (AOR 1.20, 95% confidence interval [CI] 1.08-1.34). There were no differences in the adjusted odds for poor outcomes in multiples compared with singletons in the most recent epoch: mortality (AOR 1.00, 95% CI 0.84-1.19), major morbidity (0.95, 95% CI 0.81-1.10), and composite adverse outcome (0.96, 95% CI 0.83-1.11).

CONCLUSIONS

Over the 15-year period, the odds for mortality in extremely preterm NICU infants of multiple gestation was significantly higher compared with singletons. The adjusted odds of poor outcomes in multiples were not significantly different from that of singletons in the most recent epoch.

Preterm infant outcomes in New South Wales and the Australian Capital Territory

AIM

This study aimed to provide updated information on gestation-specific hospital outcomes of extreme to very preterm infants admitted to neonatal intensive care units.

METHODS

A population-based retrospective cohort study of infants born between 23(+0) and 31(+6) weeks gestation and admitted to a network of neonatal intensive care units between 2007 and 2011 in a well-defined geographic area of New South Wales and the Australian Capital Territory. Main outcome measures were survival and major morbidities prior to hospital discharge.

RESULTS

Of 4454 infants included, hospital survival rates based on gestational age alone were 27%, 59%, 76%, 85%, 91% and over 95% at 23, 24, 25, 26, 27 and 28-31 weeks, respectively. Survival rates for each week up to 29 weeks gestation differed by at least 5% when perinatal risk factors including birthweight percentile, exposure to antenatal steroids, birth outside a tertiary hospital and gender were included in the survival estimation. All the major outcome figures were then simplified and displayed in a simple, easy-to-understand preterm outcome table for counselling purposes.

CONCLUSION

We report the latest hospital outcomes of extreme to very preterm infants in New South Wales and the Australian Capital Territory. Survival rates based on gestational age alone may not provide the true estimate as the survival for these infants can vary based on the presence or absence of other relevant perinatal factors.

Comparing CRIB-II and SNAPPE-II as mortality predictors for very preterm infants

AIMS

This article compares the severity of illness scoring systems clinical risk index for babies (CRIB)-II and score for neonatal acute physiology with perinatal extension (SNAPPE)-II for discriminatory ability and goodness of fit in the same cohort of babies of less than 32 weeks gestation and aims to provide validation in the Australian population.

METHODS

CRIB-II and SNAPPE-II scores were collected on the same cohort of preterm infants born within a 2-year period, 2003 and 2004. The discriminatory ability of each score was assessed by the area under the receiver operator characteristic curve, and goodness of fit was assessed by the Hosmer-Lemeshow (HL) test. The outcome measure was in-hospital mortality. A multivariate logistic regression model was tested for perinatal variables that might add to the risk of in-hospital mortality.

RESULTS

Data for both scores were available for 1607 infants. Both scores had good discriminatory ability (CRIB-II area under the curve 0.913, standard error (SE) 0.014; SNAPPE-II area under the curve 0.907, SE 0.012) and adequate goodness of fit (HL χ²  = 11.384, 8 degrees of freedom, P = 0.183 for CRIB-II; HL χ²  = 4.319, 7 degrees of freedom, P = 0.742 for SNAPPE-II). The multivariate model did not reveal other significant variables.

CONCLUSIONS

Both severity of illness scores are ascertained during the first 12 h of life and perform similarly. Both can facilitate risk-adjusted comparisons of mortality and quality of care after the first post-natal 12 h. CRIB-II scores have the advantage of being simpler to collect and calculate.

Auditing Neonatal Intensive Care: Is PREM a Good Alternative to CRIB for Mortality Risk Adjustment in Premature Infants?

BACKGROUND

Comparing outcomes at different neonatal intensive care units (NICUs) requires adjustment for intrinsic risk. The Clinical Risk Index for Babies (CRIB) is a widely used risk model, but it has been criticized for being affected by therapeutic decisions. The Prematurity Risk Evaluation Measure (PREM) is not supposed to be prone to treatment bias, but has not yet been validated.

OBJECTIVES

We aimed to validate the PREM, compare its accuracy to that of the original and modified versions of the CRIB and CRIB-II, and examine the congruence of risk categorization.

METHODS

Very-low-birth-weight (VLBW) infants with a gestational age (GA) <33 weeks, who were admitted to NICUs in Baden-Württemberg from 2003 to 2008, were identified from the German neonatal quality assurance program. CRIB, CRIB-II and PREM scores were calculated and modified. Omitting variables that directly reflected therapeutic decisions [the applied fraction of inspired oxygen (FiO2)] or that may have been prone to early-treatment bias (base excess and temperature), non-NICU-therapy-influenced scores were obtained. Score performance was assessed by the area under their ROC curve (AUC).

RESULTS

The CRIB showed the largest AUC (0.89), which dropped significantly (to 0.85) after omitting the FiO2. The PREM birth condition model, PREM(bcm) (AUC 0.86), and the PREM birth model, PREM(bm) (AUC 0.82), also demonstrated good discrimination. PREM(bm) was superior to other non-therapy-affected scores and to GA, particularly in infants with <750 g birth weight. Congruence of risk categorization was low, especially among higher-risk cases.

CONCLUSIONS

The CRIB score had the largest AUC, resulting from its inclusion of FiO2. PREM(bm), as the most accurate score among those unaffected by early treatment, seems to be a good alternative for strict risk adjustment in NICU auditing. It could be useful to combine scores.

Perinatal factors associated with early neonatal deaths in very low birth weight preterm infants in Northeast Brazil

Background

In Brazil, the prevalence of prematurity has increased in recent years and it is a major cause of death in the neonatal period. Therefore, this study aims at assessing perinatal factors associated with early neonatal deaths in very low birth weight preterm infants born in a region of Brazil with low Human Development Index.

Methods

Prospective cohort study of inborns with gestational age 23^0/7-31^6/7 weeks and birthweight 500-1499 g without malformations in 19 public reference hospitals of the state capitals of Brazil’s Northeast Region. Perinatal variables associated with early neonatal death were determined by Cox regression analysis.

Result

Among 627 neonates, 179 (29%) died with 0–6 days after birth. Early death was associated to: absence of antenatal steroids (HR 1.59; 95% CI 1.11-2.27), multiple gestation (1.95; 1.28-3.00), male sex (2.01; 1.40-2.86), 5th minute Apgar <7 (2.93; 2.03-4.21), birthweight <1000 g (2.58; 1.70-3.88), gestational age <28 weeks (2.07; 1.42-3.02), use of surfactant (1.65; 1.04-2.59), and non-use of a pain scale (1.89; 1.24-2.89).

Conclusion

Biological variables and factors related to the quality of perinatal care were associated with the high chance of early death of preterm infants born in reference hospitals of Northeast Brazil.

The International Network for Evaluating Outcomes of very low birth weight, very preterm neonates (iNeo): a protocol for collaborative comparisons of international health services for quality improvement in neonatal care

BACKGROUND

The International Network for Evaluating Outcomes in Neonates (iNeo) is a collaboration of population-based national neonatal networks including Australia and New Zealand, Canada, Israel, Japan, Spain, Sweden, Switzerland, and the UK. The aim of iNeo is to provide a platform for comparative evaluation of outcomes of very preterm and very low birth weight neonates at the national, site, and individual level to generate evidence for improvement of outcomes in these infants.

METHODS/DESIGN

Individual-level data from each iNeo network will be used for comparative analysis of neonatal outcomes between networks. Variations in outcomes will be identified and disseminated to generate hypotheses regarding factors impacting outcome variation. Detailed information on physical and environmental factors, human and resource factors, and processes of care will be collected from network sites, and tested for association with neonatal outcomes. Subsequently, changes in identified practices that may influence the variations in outcomes will be implemented and evaluated using quality improvement methods.

DISCUSSION

The evidence obtained using the iNeo platform will enable clinical teams from member networks to identify, implement, and evaluate practice and service provision changes aimed at improving the care and outcomes of very low birth weight and very preterm infants within their respective countries. The knowledge generated will be available worldwide with a likely global impact.

Antenatal prediction of neonatal mortality in very premature infants

OBJECTIVE

To develop a prognostic model for antenatal prediction of neonatal mortality in infants threatening to be born very preterm (<32 weeks).

STUDY DESIGN

Nationwide cohort study in The Netherlands between 1999 and 2007. We studied 8500 singletons born between 25(+0) and 31(+6) weeks of gestation where fetus was alive at birth without congenital anomalies. We developed a multiple logistic regression model to estimate the risk of neonatal mortality within 28 days after birth, based on characteristics that are known before birth. We used bootstrapping techniques for internal validation. Discrimination (AUC), accuracy (Brier score) and calibration (graph, c-statistics) were used to assess the model's predictive performance.

RESULTS

Neonatal mortality occurred in 766 (90 per 1000) live births. The final model consisted of seven variables. Predictors were low gestational age, no antental corticosteroids, male gender, maternal age ≥35 years, Caucasian ethnicity, non-cephalic presentation and non-3rd level of hospital. The predicted probabilities ranged from 0.003 to 0.697 (IQR 0.02-0.11). The model had an AUC of 0.83, the Brier score was 0.065. The calibration graph showed good calibration, and the test for the Hosmer Lemeshow c-statistic showed no lack of fit (p=0.43).

CONCLUSIONS

Neonatal mortality can be predicted for very preterm births based on the antenatal factors gestational age, antental corticosteroids, fetal gender, maternal age, ethnicity, presentation and level of hospital. This model can be helpful in antenatal counseling.

Fatores associados ao obito neonatal de recem-nascidos de alto risco: estudo multicentrico em Unidades Neonatais de Alto Risco no Nordeste brasileiro

Este estudo pretendeu determinar os fatores associados à mortalidade intra-hospitalar, utilizando como variáveis explicativas as características individuais da mãe, da assistência ao pré-natal, parto e período neonatal e dos recém-nascidos internados em Unidades Neonatais de Alto Risco (UTIN) integrantes da Rede Norte-Nordeste de Saúde Perinatal no Nordeste do Brasil. Foi realizado estudo longitudinal, multicêntrico de base hospitalar. A população do estudo compreendeu 3.623 nascidos vivos internados em 34 UTIN. Após o ajuste para os três níveis hierárquicos do modelo de determinação do óbito em UTIN até o 27 o dia de vida, associaram-se: tipo de parto – cesariana (OR = 0,72; IC95%: 0,56-0,95); não uso de corticoide antenatal (OR = 1,51; IC95%: 1,01-2,25); pré-eclâmpsia (OR = 0,73; IC95%: 0,56-0,95); oligodramnia (OR = 1,57; IC95%: 1,17-2,10); peso ao nascer < 2.500g (OR = 1,40; IC95%: 1,03-1,90); escore de Apgar 5 o minuto < 7 (OR = 2,63; IC95%: 2,21-3,14); uso de tubo endotraqueal (OR = 1,95; IC95%: 1,31-2,91); não uso de surfactante (OR = 0,54; IC95%: 0,43-0,69). O óbito em UTIN é determinado pelas condições assistenciais à gestação, parto e recém-nato.

Use of risk stratification indices to predict mortality in critically ill children

The complexity and high cost of neonatal and pediatric intensive care has generated increasing interest in developing measures to quantify the severity of patient illness. While these indices may help improve health care quality and benchmark mortality across hospitals, comprehensive understanding of the purpose and the factors that influenced the performance of risk stratification indices is important so that they can be compared fairly and used most appropriately. In this review, we examined 19 indices of risk stratification used to predict mortality in critically ill children and critically analyzed their design, limitations, and purposes. Some pediatric and neonatal models appear well-suited for institutional benchmarking purposes, with relatively brief data acquisition times, limited potential for treatment-related bias, and reliance on diagnostic variables that permit adjustment for case mix. Other models are more suitable for use in clinical trials, as they rely on physiologic variables collected over an extended period, to better capture the interaction between organ systems function and specific therapeutic interventions in acutely ill patients. Irrespective of their clinical or research applications, risk stratification indices must be periodically recalibrated to adjust for changes in clinical practice in order to remain valid outcome predictors in pediatric intensive care units. Longitudinal auditing, education, training, and guidelines development are also critical to ensure fidelity and reproducibility in data reporting.

CONCLUSION

Risk stratification indices are valid tools to describe intensive care unit population and explain differences in mortality.

Infant mortality in a very low birth weight cohort from a public hospital in Rio de Janeiro, RJ, Brazil

OBJECTIVES: to evaluate infant mortality in very low birth weight newborns from a public hospital in Rio de Janeiro, Brazil (2002-2006). METHODS: a retrospective cohort study was performed using the probabilistic linkage method to identify infant mortality. Mortality proportions were calculated according to birth weight intervals and period of death. The Kaplan-Meier method was used to estimate overall cumulative survival probability. The association between maternal schooling and survival of very low birth weight infants was evaluated by means of Cox proportional hazard models adjusted for: prenatal care, birth weight, and gestational age. RESULTS: the study included 782 very low birth weight newborns. Of these, (28.6%) died before one year of age. Neonatal mortality was 19.5%, and earlyneonatal mortality was 14.9%. Mortality was highest in the lowest weight group (71.6%). Newborns whose mothers had less than four years of schooling had 2.5 times higher risk of death than those whose mothers had eight years of schooling or more, even after adjusting for intermediate factors. CONCLUSIONS: the results showed higher mortality among very low birth weight infants. Low schooling was an independent predictor of infant death in this low-income population sample.

Obstetric and neonatal care practices for infants 501 to 1500 g from 2000 to 2009

OBJECTIVE

To identify changes in clinical practices for infants with birth weights of 501 to 1500 g born from 2000 to 2009.

METHODS

We used prospectively collected registry data for 355,806 infants born from 2000 to 2009 and cared for at 669 North American hospitals in the Vermont Oxford Network. Main outcome measures included obstetric and neonatal practices, including cesarean delivery, antenatal steroids, delivery room interventions, respiratory practices, neuroimaging, retinal exams, and feeding at discharge.

RESULTS

Significant changes in many obstetric, delivery room, and neonatal practices occurred from 2000 to 2009. Use of surfactant treatment in the delivery room increased overall (adjusted difference [AD] 17.0%; 95% confidence interval [CI] 16.4% to 17.6%), as did less-invasive methods of respiratory support, such as nasal continuous positive airway pressure (AD 9.9%; 95% CI 9.1% to 10.6%). Use of any ventilation (AD -7.5%; 95% CI -8.0% to -6.9%) and steroids for chronic lung disease (AD -15.3%; 95% CI -15.8% to -14.8%) decreased significantly overall. Most of the changes in respiratory care were observed within each of 4 birth weight strata (501-750 g, 751-1000 g, 1001-1250 g, 1251-1500 g).

CONCLUSIONS

Many obstetric and neonatal care practices used in the management of infants 501 to 1500 g changed between 2000 and 2009. In particular, less-invasive approaches to respiratory support increased.

Aorta structural alterations in term neonates: the role of birth and maternal characteristics

AIM

To evaluate the influence of selected maternal and neonatal characteristics on aorta walls in term, appropriately grown-for-gestational age newborns.

METHODS

Age, parity, previous abortions, weight, height, body mass index before and after delivery, smoking, and history of hypertension, of diabetes, of cardiovascular diseases, and of dyslipidemia were all assessed in seventy mothers. They delivered 34 males and 36 females healthy term newborns who underwent ultrasound evaluation of the anteroposterior infrarenal abdominal aorta diameter (APAO), biochemical profile (glucose, insulin, total cholesterol, HDL and LDL cholesterol, triglycerides, fibrinogen, and D-dimers homeostasis model assessment [HOMAIR]index), and biometric parameters.

RESULTS

APAO was related to newborn length (r = +0.36; P = 0.001), head circumference (r = +0.37; P = 0.001), gestational age (r = +0.40, P = 0.0005), HOMA index (r = +0.24; P = 0.04), and D-dimers (r = +0.33, P = 0.004). Smoke influenced APAO values (odds ratio: 1.80; confidence interval 95%: 1.05-3.30), as well as diabetes during pregnancy (r = +0.42, P = 0.0002). Maternal height influenced neonatal APAO (r = +0.47, P = 0.00003). Multiple regression analysis outlined neonatal D-dimers as still significantly related to neonatal APAO values.

CONCLUSIONS

Many maternal and neonatal characteristics could influence aorta structures. Neonatal D-dimers are independently related to APAO.

Aorta structural alterations in term neonates: the role of birth and maternal characteristics

Aim. To evaluate the influence of selected maternal and neonatal characteristics on aorta walls in term, appropriately grown-for-gestational age newborns. Methods. Age, parity, previous abortions, weight, height, body mass index before and after delivery, smoking, and history of hypertension, of diabetes, of cardiovascular diseases, and of dyslipidemia were all assessed in seventy mothers. They delivered 34 males and 36 females healthy term newborns who underwent ultrasound evaluation of the anteroposterior infrarenal abdominal aorta diameter (APAO), biochemical profile (glucose, insulin, total cholesterol, HDL and LDL cholesterol, triglycerides, fibrinogen, and D-dimers homeostasis model assessment [HOMA_IR]index), and biometric parameters. Results. APAO was related to newborn length (r = +0.36; P = 0.001), head circumference (r = +0.37; P = 0.001), gestational age (r = +0.40, P = 0.0005), HOMA index (r = +0.24; P = 0.04), and D-dimers (r = +0.33, P = 0.004). Smoke influenced APAO values (odds ratio: 1.80; confidence interval 95%: 1.05–3.30), as well as diabetes during pregnancy (r = +0.42, P = 0.0002). Maternal height influenced neonatal APAO (r = +0.47, P = 0.00003). Multiple regression analysis outlined neonatal D-dimers as still significantly related to neonatal APAO values. Conclusions. Many maternal and neonatal characteristics could influence aorta structures. Neonatal D-dimers are independently related to APAO.

Outcomes of small for gestational age infants born at <27 weeks' gestation

OBJECTIVE

To determine whether small for gestational age (SGA) infants born at <27 weeks gestational age (GA) are at increased risk for mortality, morbidity, and growth and neurodevelopmental impairment at 18-22 months corrected age.

STUDY DESIGN

This was a retrospective cohort study from National Institute of Child Health and Human Development Neonatal Research Network's Generic Database and Follow-Up Studies. Infants born at <27 weeks GA between January 2006 and July 2008 were included. SGA was defined as birth weight <10th percentile for GA based on Olsen growth curves. Infants with birth weight ≥ 10th percentile for GA were classified as non-SGA. Maternal and infant characteristics, neonatal outcomes, and neurodevelopmental data were compared in SGA and non-SGA infants. Neurodevelopmental impairment was defined as any of the following: cognitive score <70 on the Bayley Scales of Infant Development III, moderate or severe cerebral palsy, bilateral hearing loss (with and without amplification), or blindness (bilateral vision <20/200). Logistic regression analysis was applied to evaluate the associations between SGA status and death or neurodevelopmental impairment.

RESULTS

The SGA group comprised 385 infants; the non-SGA group, 2586 infants. Compared with mothers of non-SGA infants, mothers of SGA infants were more likely to have a high school education, prenatal care, cesarean delivery, pregnancy-induced hypertension, and antenatal corticosteroid exposure. Compared with non-SGA infants, SGA infants had higher mortality and were more likely to have postnatal growth failure, prolonged mechanical ventilation, and postnatal steroid use. SGA status was associated with increased risk of death or neurodevelopmental impairment (OR, 3.91; 95% CI, 2.91-5.25; P < .001).

CONCLUSION

SGA status in infants born at <27 weeks GA is associated with an increased likelihood of postnatal steroid use, mortality, growth failure, and neurodevelopmental impairment at 18-22 months corrected age.

Cause-specific mortality of very preterm infants and antenatal events

OBJECTIVE

To assess the relationship between antenatal factors and cause-specific risk of death in a large area-based cohort of very preterm infants.

STUDY DESIGN

The ACTION (Accesso alle Cure e Terapie Intensive Ostetriche e Neonatali) study recruited during an 18-month period all infants 22-31 weeks' gestational age admitted to neonatal care in 6 Italian regions (n=3040). We analyzed the data of 2974 babies without lethal or acutely life-threatening malformations. Cause-specific risks of death adjusted for competing causes were calculated, and region-stratified multiple Cox regression analyses were used to study the association between cause-specific mortality and infants' characteristics, pregnancy complications, antenatal steroids, and place of birth.

RESULTS

Deaths attributable to respiratory problems and intraventricular hemorrhage prevailed in the first 2 weeks of life, and those attributable to infections and gastrointestinal diseases afterwards. Antepartum hemorrhage was associated with respiratory deaths (hazard ratio [HR] 1.6, 95% CI 1.1-2.4), and maternal infection with deaths attributable to asphyxia (HR 32.5, 95% CI 4.1-259.4) and to respiratory problems (HR 2.8, 95% CI 1.6-5.2). Preterm premature rupture of membranes increased the likelihood of deaths due to neonatal infection (HR 1.8, 95% CI 1.0-3.1), and preterm labor/contractions of those due to respiratory (HR 1.5, 95% CI 1.1-2.0) and gastrointestinal diseases (HR 5.8, 95% CI 2.1-16.3). In addition, a birth weight z-score<-1 was associated with increasing hazards of death resulting from asphyxia, late infections, respiratory, and gastrointestinal diseases.

CONCLUSIONS

Different complications of pregnancy lead to different cause-specific mortality patterns in very preterm infants.

Population-based estimates of in-unit survival for very preterm infants

BACKGROUND

Estimates of the probability of survival of very preterm infants admitted to NICU care are vital for counseling parents, informing care, and planning services. In 1999, easy-to-use charts of survival according to gestation, birth weight, and gender were published in the United Kingdom. These charts are widely used in clinical care and for benchmarking survival, and they form the core of the Clinical Risk Index for Babies II score. Since their publication, the survival of preterm infants has improved, and the charts therefore need updating.

METHODS

A logistic model was fitted with gestational age, birth weight, and gender. Nonlinear functions were estimated by using fractional polynomials. Bootstrap methods were used to assess the internal validity of the final model. The final model was assessed both overall and for subgroups of infants by using Farrington's statistic, the c-statistic, Cox regression coefficients, and the Brier score.

RESULTS

A total of 2995 white singleton infants born at 23(+0) to 32(+6) weeks' gestation in 2008 through 2010 were identified; 2751 (91.9%) infants survived to discharge. A prediction model was estimated and good model fit confirmed (area under receiver-operating characteristics curve = 0.86). Survival ranged from 27.7% (23 weeks) to 99.1% (32 weeks) for boys and from 34.5% (23 weeks) to 99.3% (32 weeks) for girls. Updated charts were produced showing estimated survival according to gestation, birth weight and gender, together with contour plots displaying points of equal survival.

CONCLUSIONS

These survival charts have been updated and will be of use to clinicians, parents, and managers.

Maternal preeclampsia is associated with increased risk of necrotizing enterocolitis in preterm infants

BACKGROUND

Necrotizing enterocolitis (NEC) is an important cause of mortality and morbidity in preterm infants.

AIMS

To evaluate the effect of maternal preeclampsia on the development and severity of NEC in premature infants.

STUDY DESIGN

Prospective observational study in a tertiary neonatal intensive care unit.

SUBJECTS

The preterm infants of ≤ 37 gestational age who were consecutively hospitalized were enrolled. The study group contained preterm infants born to a preeclamptic mother and the comparison group contained preterm infants born to a normotensive mother.

OUTCOME MEASURES

The primary outcome was to determine the association between preeclampsia and NEC.

RESULTS

A total of 88 infants had NEC diagnosis. The incidence of NEC in infants born to preeclamptic mothers (22.9%) was significantly higher compared with those born to normotensive mothers (14.6%). According to NEC stages, NEC was more advanced in preeclamptic mother infants. NEC developed significantly earlier in infants with NEC in the study group. The duration of NEC was also significantly longer in infants born to preeclamptic mothers. In multiple logistic regression model, preeclampsia was found to be predictive of NEC with an odds ratio of 1.74 (95% confidence interval 0.64-0.92).

CONCLUSIONS

Maternal preeclampsia may be an important risk factor for the development of NEC in premature infants as NEC incidence and severity of NEC were found to be significantly higher in premature infants born to preeclamptic mothers. The onset of NEC was significantly earlier and duration of NEC was longer in these infants.

Comparison of mortality and morbidity of very low birth weight infants between Canada and Japan

OBJECTIVE

To compare neonatal outcomes of very low birth weight (VLBW) infants admitted to NICUs participating in the Canadian Neonatal Network and the Neonatal Research Network of Japan.

METHODS

Secondary analyses of VLBW infants in both national databases between 2006 and 2008 were conducted. The primary outcome was a composite of mortality or any major morbidity defined as severe neurologic injury, bronchopulmonary dysplasia, necrotizing enterocolitis, or severe retinopathy of prematurity at discharge. Secondary outcomes included individual components of primary outcome and late-onset sepsis. Logistic regression adjusting for confounders was performed.

RESULTS

A total of 5341 infants from the Canadian Neonatal Network and 9812 infants from the Neonatal Research Network of Japan were compared. There were higher rates of maternal hypertension, diabetes mellitus, outborn, prenatal steroid use, and multiples in Canada, whereas cesarean deliveries were higher in Japan. Composite primary outcome was better in Japan in comparison with Canada (adjusted odds ratio [AOR] 0.87, 95% confidence interval [CI] 0.79-0.96). The odds of mortality (AOR 0.40, 95% CI 0.34-0.47), severe neurologic injury (AOR 0.57, 95% CI 0.49-0.66), necrotizing enterocolitis (AOR 0.23, 95% CI 0.19-0.29), and late-onset sepsis (AOR 0.22, 95% CI 0.19-0.25) were lower in Japan; however, the odds of bronchopulmonary dysplasia (AOR 1.24, 95% CI 1.10-1.42) and severe retinopathy of prematurity (AOR 1.98, 95%CI 1.69-2.33) were higher in Japan.

CONCLUSIONS

Composite outcome of mortality or major morbidity was significantly lower in Japan than Canada for VLBW infants. However, there were significant differences in various individual outcomes identifying areas for improvement for both networks.

Mortality risk after neonatal seizures in very preterm newborns

We analyzed clinical and instrumental data of 403 consecutive newborns with gestational age from 24 to 32 weeks, admitted to the University-Hospital of Parma between January 2000 and December 2007, to evaluate the possible relationship between neonatal mortality and occurrence of neonatal seizures in very preterm newborns. Seventy-four subjects died during hospital stay. Seizures were present in 35 neonates, in whom the mortality rate was 37.1%. Multivariate analysis revealed that birth-weight <1000 g (odds ratio: 4.48; 95% confidence interval: 1.47-13.68; P < .01), cardiopulmonary resuscitation (odds ratio: 5.35; 95% confidence interval: 1.19-23.98; P = .02), and moderately and severely abnormal cerebral ultrasound scan findings (odds ratio: 2.48; 95% confidence interval: 1.02-6.05; P < .04; odds ratio: 9.56; 95% confidence interval: 3.45-26.51; P < .01, respectively) were related to the in-hospital mortality but not the presence of neonatal seizures. Our study suggests that neonatal seizures alone are not an independent risk factor for early death in very preterm newborns.

Prediction of mortality in very premature infants: a systematic review of prediction models

Context

Being born very preterm is associated with elevated risk for neonatal mortality. The aim of this review is to give an overview of prediction models for mortality in very premature infants, assess their quality, identify important predictor variables, and provide recommendations for development of future models.

Methods

Studies were included which reported the predictive performance of a model for mortality in a very preterm or very low birth weight population, and classified as development, validation, or impact studies. For each development study, we recorded the population, variables, aim, predictive performance of the model, and the number of times each model had been validated. Reporting quality criteria and minimum methodological criteria were established and assessed for development studies.

Results

We identified 41 development studies and 18 validation studies. In addition to gestational age and birth weight, eight variables frequently predicted survival: being of average size for gestational age, female gender, non-white ethnicity, absence of serious congenital malformations, use of antenatal steroids, higher 5-minute Apgar score, normal temperature on admission, and better respiratory status. Twelve studies met our methodological criteria, three of which have been externally validated. Low reporting scores were seen in reporting of performance measures, internal and external validation, and handling of missing data.

Conclusions

Multivariate models can predict mortality better than birth weight or gestational age alone in very preterm infants. There are validated prediction models for classification and case-mix adjustment. Additional research is needed in validation and impact studies of existing models, and in prediction of mortality in the clinically important subgroup of infants where age and weight alone give only an equivocal prognosis.

Maternal preeclampsia is associated with an increased risk of retinopathy of prematurity

OBJECTIVE

To determine the effect of maternal preeclampsia on development and severity of retinopathy of prematurity (ROP) in preterm infants.

METHODS

This prospective study consisted of two groups: the study group, which is composed of preterm infants (≤32 weeks) born to a mother with preeclampsia, and the comparison group, which is composed of preterm infants (≤32 gestational age) born to normotensive mothers. We used the International Classification of Retinopathy of Prematurity Revisited for classifying ROP. The first eye examination was performed at postnatal age of 4 weeks.

RESULTS

A total of 385 infants were included in the study. ROP was diagnosed in 109 infants (28%). The incidence of ROP in infants born to preeclamptic mothers (40.5%) was significantly higher compared with those born to normotensive mothers (22.4%) (P<0.05). The number of infants with stage 1, 2, and 3 ROP was significantly higher in infants born to preeclamptic mothers compared with the control group (P<0.05). In multiple logistic regression model, preeclampsia was found to predict ROP (odds ratio 1.78, 95% confidence interval 0.66-1.90).

CONCLUSION

Maternal preeclampsia was found to be associated with increased ROP development risk in premature infants. ROP was also more severe in infants born to pre-eclamptic mothers. The role of maternal preeclampsia in the occurrence and severity of ROP remains to be elucidated.

Renal programming: cause for concern?

Development of the kidney can be altered in utero in response to a suboptimal environment. The intrarenal factors that have been most well characterized as being sensitive to programming events are kidney mass/nephron endowment, the renin-angiotensin system, tubular sodium handling, and the renal sympathetic nerves. Newborns that have been subjected to an adverse intrauterine environment may thus begin life at a distinct disadvantage, in terms of renal function, at a time when the kidney must take over the primary role for extracellular fluid homeostasis from the placenta. A poor beginning, causing renal programming, has been linked to increased risk of hypertension and renal disease in adulthood. However, although a cause for concern, increasingly, evidence demonstrates that renal programming is not a fait accompli in terms of future cardiovascular and renal disease. A greater understanding of postnatal renal maturation and the impact of secondary factors (genes, sex, diet, stress, and disease) on this process is required to predict which babies are at risk of increased cardiovascular and renal disease as adults and to be able to devise preventative measures.

Improving the quality of care for infants: a cluster randomized controlled trial

BACKGROUND

We developed and tested a new method, called the Evidence-based Practice for Improving Quality method, for continuous quality improvement.

METHODS

We used cluster randomization to assign 6 neonatal intensive care units (ICUs) to reduce nosocomial infection (infection group) and 6 ICUs to reduce bronchopulmonary dysplasia (pulmonary group). We included all infants born at 32 or fewer weeks gestation. We collected baseline data for 1 year. Practice change interventions were implemented using rapid-change cycles for 2 years.

RESULTS

The difference in incidence trends (slopes of trend lines) between the ICUs in the infection and pulmonary groups was - 0.0020 (95% confidence interval [CI] - 0.0007 to 0.0004) for nosocomial infection and - 0.0006 (95% CI - 0.0011 to - 0.0001) for bronchopulmonary dysplasia.

INTERPRETATION

The results suggest that the Evidence-based Practice for Improving Quality method reduced bronchopulmonary dysplasia in the neonatal ICU and that it may reduce nosocomial infection.

The establishment of the Australian and New Zealand Neonatal Network

The Australian and New Zealand Neonatal Network was established in 1994 to monitor high-risk newborns admitted for care. Uniquely, all units in both countries have participated since inception, making it integral to the care of babies. The network's objectives include auditing care, publishing aggregated results annually, providing feedback to units, monitoring technologies and developing clinical indicators. Networking provides a forum for clinicians and a consortium of knowledge and advice. It facilitates collaborative research and clinical groups, producing projects from observational studies to randomised controlled trials. Members take a major role in reviewing the evidence for care and ensuring its effective use in clinical practice.

Habilidades do desenvolvimento de prematuros

OBJETIVO: verificar o desempenho de habilidades do desenvolvimento linguístico, cognitivo, motor, de autocuidados e socialização em crianças prematuras. MÉTODOS: participaram 30 crianças nascidas prematuras, de ambos os sexos de seis a 24 meses. Os procedimentos de avaliação constaram de uma entrevista de anamnese e da aplicação do Inventário Portage Operacionalizado (IPO) (Wilhiams & Aiello, 2001). As crianças foram divididas em dois grupos, conforme a faixa etária, para análise estatística dos dados, considerando as idades de seis a 11 meses e de 12 a 24 meses. A análise dos dados foi realizada por meio da aplicação do teste Manny-Whitney comparando os valores obtidos no grupo de crianças prematuras com escores previstos para crianças típicas. RESULTADOS: os resultados indicam que a área mais defasada do grupo na faixa etária de seis a 12 meses foi à linguística e autocuidados e na faixa etária de 12 a 24 meses as áreas mais defasadas foram linguística, cognitiva e de autocuidados. CONCLUSÃO: ressalta-se a necessidade de um acompanhamento rigoroso de recém-nascidos prematuros, por meio do desenvolvimento de programas de acompanhamento e por uma equipe multidisciplinar para promover a detecção e intervenção precoce, minimizando assim o impacto de problemas no desenvolvimento global destas crianças.