Neonatal Outcomes of Very Low Birth Weight and Very Preterm Neonates: An International Comparison

Morbidity in ≤1500-Gram Births in Spain, 1993-2011: Study of a Sample of 1200 Cases

Background and Objective. Preterm birth has a major impact on growth, and very preterm birth is associated with disabilities in numerous developmental domains. This article describes and quantifies morbidities in a sample of 1200 ≤1500-g births in Spain between 1993 and 2011 based on parent information, and it highlights several variables that influence these morbidities. Methods. Multiple method surveys using computer-assisted telephones interviewing and computer-assisted web interviewing methods. Sample design was intentional. Most subjects were contacted via their referral hospitals. Data collection was done from April 2013 to June 2014. Prior to the survey, extensive qualitative fieldwork was conducted, including nonparticipant observation in neonatal units and the design and analysis of discussion groups and interviews with professionals and families, including preterm adolescents. Results. A total of 44.2% of the sample were experiencing morbidity (mean: 1.788 morbidities per child). The most prevalent types were learning difficulties (34.4%) and attention deficit/hyperactivity disorder (31.5%). The most influential variables were male gender, age, lower birthweight, private hospital admission for birth, scarcity of health resources in the family's residential area, non-Spanish maternal birthplace, and emotional distress in the primary carer. Conclusions. Overall, the total percentage of very low birth weight children with morbidities has decreased moderately between 1993 and 2011, thanks to major socio-sanitary improvements during this period. Biological and medical variables, rather than family factors, explain more accurately the presence of morbidities in children with birth weight ≤1500 g.

Morbidity and mortality of very low birth weight multiples compared with singletons

BACKGROUND

Previous studies comparing the neonatal outcome of very low birth weight (VLBW) multiples and singletons have suggested a worse outcome for multiples at gestational ages on the limits of viability.

OBJECTIVES

The objective of this study is to determine the neonatal mortality and morbidity of VLBW multiples compared to singletons.

METHODS

This is a retrospective study including all infants registered in the Spanish network for infants under 1500 g (SEN1500), over a 12-year period (from 2002 to 2013). Mortality and major morbidities were compared between singletons and multiples.

RESULTS

About 32,770 infants were included: 21,123 singletons (64.5%) and 11,647 multiples (35.5%), with a mean gestational age of 29.5 weeks (22-38), and mean birth weight of 1115 g (340-1500). When adjusted by other perinatal factors, multiple pregnancy has a significantly higher risk of mortality than singleton pregnancy (odds ratio (OR) 1.15; IC 95% 1.05-1.26, p = .002), but not a higher risk of major morbidity or composite adverse outcome. In the subgroup of infants born before 26 weeks, multiples showed a higher risk of mortality (63.9% versus 51%, OR 1.7; 95% CI 1.47-1.96) and a higher risk of composite adverse outcome (88.9% versus 81.5%, OR 1.82, 95% CI 1.28-2.24).

CONCLUSIONS

In preterm infants born with less than 1500 g, multiple pregnancy is a prognostic factor that can slightly increase mortality. Extremely preterm infants born before 26 weeks have a greater risk of mortality and major morbidity if they come from a multiple pregnancy.

Improvement in the Survival Rates of Very Low Birth Weight Infants after the Establishment of the Korean Neonatal Network: Comparison between the 2000s and 2010s

The survival rate (SR) of very low birth weight infants (VLBWIs) and extremely low birth weight infants (ELBWIs) is a health indicator of neonatal intensive care unit (NICU) outcomes. The Korean Neonatal Network (KNN) was established in 2013, and a system has been launched to manage the registration and quality improvement of VLBWIs. The SR of the VLBWIs significantly increased to 85.7% in the 2010s compared with 83.0% in the 2000s. There was also a significant increase in the SR of the ELBWIs from 66.1% to 70.7%. The equipment, manpower, and assistance systems of NICUs also improved in quantity and quality. In the international comparison of the SRs of VLBWIs, the SRs were 93.8%, 92.2%, 90.2%, 89.4%, 86.4%, 85.1%, and 80.6% in Japan, Australia and New Zealand, Canada, Europe, Korea, Taiwan, and United States, respectively. In conclusion, the SRs of the VLBWIs and ELBWIs improved in the 2010s compared with those in the 2000s in Korea. This improvement is considered to have been related to the role of the KNN built in 2013. However, the latest VLBWI and ELBWI SRs in 2015 are still low compared with those in Japan, Australia and New Zealand, Canada, and Europe. In the future, we must establish and develop the tasks that are presented as future tasks in this review.

Recent advances in the prevention of preterm birth

Preterm birth (PTB) remains a major obstetric healthcare problem and a significant contributor to perinatal morbidity, mortality, and long-term disability. Over the past few decades, the perinatal outcomes of preterm neonates have improved markedly through research and advances in neonatal care, whereas rates of spontaneous PTB have essentially remained static. However, research into causal pathways and new diagnostic and treatment modalities is now bearing fruit and translational initiatives are beginning to impact upon PTB rates. Successful PTB prevention requires a multifaceted approach, combining public health and educational programs, lifestyle modification, access to/optimisation of obstetric healthcare, effective prediction and diagnostic modalities, and the application of effective, targeted interventions. Progress has been made in some of these areas, although there remain areas of controversy and uncertainty. Attention is now being directed to areas where greater gains can be achieved. In this mini-review, we will briefly and selectively review a range of PTB prevention strategies and initiatives where progress has been made and where exciting opportunities await exploitation, evaluation, and implementation.

Methodological Challenges in International Comparisons of Perinatal Mortality

PURPOSE OF REVIEW

Several prestigious agencies routinely rank countries based on crude perinatal and infant mortality rates, while more recently, international neonatal networks have begun comparing neonatal mortality and morbidity rates among very preterm and very low-birth-weight infants. We discuss the methodologic challenges that compromise such comparisons and potential remedies.

RECENT FINDINGS

Crude perinatal mortality rates are biased by international variations in birth registration, especially at the borderline of viability. Such bias is demonstrated by significant differences in crude versus birth weight- and gestational age-specific comparisons of perinatal mortality. Comparisons of neonatal mortality among very preterm and very low-birth-weight infants are plagued by incorrect denominators, and this leads to paradoxical findings.

SUMMARY

A lack of standardization with regard to birth registration and inadequate appreciation of the methods for calculating gestational age-specific mortality rates are responsible for biasing international comparisons of perinatal mortality.

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.

Survival of Infants Born at Periviable Gestational Ages

Periviable births are those occurring from 20 0/7 through 25 6/7 weeks of gestation. Among and within developed nations, significant variation exists in the approach to obstetric and neonatal care for periviable birth. Understanding gestational age-specific survival, including factors that may influence survival estimates and how these estimates have changed over time, may guide approaches to the care of periviable births and inform conversations with families and caregivers. This review provides a historical perspective on survival following periviable birth, summarizes recent and new data on gestational age-specific survival rates, and addresses factors that have a significant impact on survival.

Bronchopulmonary Dysplasia: Where Have All the Stem Cells Gone?: Origin and (Potential) Function of Resident Lung Stem Cells

Celebrating its 50th anniversary in 2017, bronchopulmonary dysplasia (BPD)-the chronic lung disease of prematurity that follows ventilator and oxygen therapy for acute respiratory failure-remains the most frequent complication of extreme prematurity. Survival of premature infants born at increasingly earlier stages of gestation has made the prevention of lung injury increasingly challenging. BPD is postulated to be a misdirection of many functions in the developing lung, including growth factor signalling and matrix as well as cellular composition, resulting in impaired alveolar and lung vascular growth. Despite improvements in understanding the mechanisms that regulate normal lung development, BPD remains without therapies. Insights into stem cell biology have identified the repair potential of stem cells. Promising preclinical studies demonstrated the lung protective effects of stem cell-based therapies in animal models mimicking BPD, leading to early-phase clinical trials. Although the time is ripe to conduct well-designed early-phase clinical trials, much more needs to be learned about the biology of these cells to develop safe, efficient, high-quality, clinical-grade cell products. Stem cells are essential for normal organ development, maintenance, and repair. It is therefore biologically plausible that exhaustion/dysfunction of resident lung stem cells contributes to the inability of the immature lung to repair itself. Understanding how normal lung stem cells function and how these cells are perturbed in BPD may prove useful in designing superior cell products with enhanced repair capabilities to ensure the successful translation of basic research into clinical practice.

Role of cytokines and treatment algorithms in retinopathy of prematurity

PURPOSE OF REVIEW

Currently, severe retinopathy of prematurity (ROP) is diagnosed by clinical evaluation and not a laboratory test. Laser is still considered standard care. However, anti-vascular endothelial growth factor (VEGF) agents are being used and there are questions whether and/or if to use them, what dose or type of agent should be considered and what agent may be most beneficial in specific cases. Also unclear are the effects of laser or anti-VEGF on severe ROP, refractive outcomes or infant development. This article reviews recent studies related to these questions and other trials for severe ROP.

RECENT FINDINGS

Imaging studies identify biomarkers of risk (plus disease, stage 3 ROP, and ROP in zone I). Intravitreal bevacizumab or ranibizumab are reported effective in treating aggressive posterior ROP in small series. Recurrences and effects on myopia vary among studies. Use of anti-VEGF agents affects cytokines in the infant blood and reduces systemic VEGF for up to 2 months, raising potential safety concerns. The effects of treatment vary based on infant size and are not comparable. Evidence for most studies is not high.

SUMMARY

Studies support experimental evidence that inhibiting VEGF reduces stage 3 ROP and peripheral avascular retina. Ongoing large-scale clinical trials may provide clarity for best treatments of severe ROP. Current guidelines hold for screening and treatment for type 1 ROP.

[Family-Centered Care in Neonatal Intensive Care Units: Combining Intensive Care and Family Support]

Advances in treatment in neonatal intensive care units (NICU) for preterm and sick newborns have improved the mortality rate of patients, but admission to the NICU may disrupt parent-infant interaction, with adverse consequences for infants and their families because of physical, psychological, and emotional separation. The concept of family centered care (FCC), in which family members are part of the care team and infants are close to the family, is important and has become popular in NICU. In 2013, we created a team called "Kodomo-Kazoku Mannaka" to promote FCC in Japan, and visited the NICU at Uppsala University Hospital in Sweden, which is internationally famous for FCC. Since this fruitful visit, we have been promoting FCC in Japan by exhibitions and presentations of the FCC ideas at academic conferences and using internet services. A questionnaire survey conducted in 2015 revealed that the importance and the benefits of FCC in NICU are recognized, although there are some barriers to FCC in each facility. It is hard to change facilities and social systems right away, but it is easier and more important to change people's minds. Our role is to spread the concept of FCC and to help each facility find its own way to adopt it. We will continue to make efforts encourage to promote FCC in Japan.

Developing, implementing and disseminating a core outcome set for neonatal medicine

BACKGROUND

In high resource settings, 1 in 10 newborn babies require admission to a neonatal unit. Research evaluating neonatal care involves recording and reporting many different outcomes and outcome measures. Such variation limits the usefulness of research as studies cannot be compared or combined. To address these limitations, we aim to develop, disseminate and implement a core outcome set for neonatal medicine.

METHODS

A steering group that includes parents and former patients, healthcare professionals and researchers has been formed to guide the development of the core outcome set. We will review neonatal trials systematically to identify previously reported outcomes. Additionally, we will specifically identify outcomes of importance to parents, former patients and healthcare professionals through a systematic review of qualitative studies. Outcomes identified will be entered into an international, multi-perspective eDelphi survey. All key stakeholders will be invited to participate. The Delphi method will encourage individual and group stakeholder consensus to identify a core outcome set. The core outcome set will be mapped to existing, routinely recorded data where these exist.

DISCUSSION

Use of a core set will ensure outcomes of importance to key stakeholders, including former patients and parents, are recorded and reported in a standard fashion in future research. Embedding the core outcome set within future clinical studies will extend the usefulness of research to inform practice, enhance patient care and ultimately improve outcomes. Using routinely recorded electronic data will facilitate implementation with minimal addition burden.

TRIAL REGISTRATION NUMBER

Core Outcome Measures in Effectiveness Trials (COMET) database: 842 (www.comet-initiative.org/studies/details/842).