Improved survival and neurodevelopmental outcomes among extremely premature infants born near the limit of viability

A scoping review of the epidemiology and treatment of painful procedures in hospitalized neonates: What has changed in the past three decades?

BACKGROUND

Care of newborns hospitalized in the neonatal intensive care unit (NICU) includes multiple painful procedures/day. Epidemiologic studies have reported the frequency and nature of procedures and treatment interventions. However, evidence on the changing trends in the nature and frequency of neonatal pain procedures or treatments over time is absent or inconclusive. We aimed to determine the frequency and nature of painful procedures/neonate/day in the NICU.

DATABASES AND DATA TREATMENT

MEDLINE and Embase searches were conducted from database inception to July 2023. Studies that reported the nature and frequency of painful procedures and associated pain treatments in neonates were included. Standard inverse-variance random-effects meta-analyses were used to combine studies. Heterogeneity between studies was quantified using the I2 statistic.

RESULTS

Of 2622 unique citations, 64 full-text articles were reviewed; 23 were included. Six additional studies identified in a previous review, and six publications from reference lists were added, resulting in 35 studies. The mean number of painful procedures/neonate/day was 7.38 (95% CI 5.60, 9.17; range <2 to 17). Although the frequency of painful procedures in more recent studies was reduced, it was not statistically significant (p = 0.16). Painful procedures were more frequent during longer observation periods. Needle-related procedures were most common and did not change over time. Procedure-related treatment was suboptimal and inconsistently reported.

CONCLUSIONS

Frequency of painful procedures in the NICU has shown a clinically important decrease but has not significantly changed over time. A paradigm shift moving responsibility from providers to systems in changing pain practices in the NICU is required.

SIGNIFICANCE STATEMENT

The decrease in the daily frequency of painful procedures in hospitalized neonates might be clinically relevant but is not yet statistically significant. Pain treatment is insufficiently documented and reported. This lack of progress in neonatal care might be a result of the complexity of defining pain and stress; inconsistencies in determining the burden of procedural pain; the influence of barriers and facilitators on practice change; and the focus on an individual rather than system responsibility for pain prevention and treatment.

Risk assessment of survival and morbidity of infants born at <24 completed weeks of gestation

BACKGROUND

Infants born at the threshold of viability have a high risk of mortality and morbidity. The British Association of Perinatal Medicine (BAPM) provided updated guidance in 2019 advising a risk-based approach to balancing decisions about active versus redirected care at birth.

AIMS

To determine survival and morbidity of infants born between 22 and 24 completed weeks of gestation. To develop a scoring system to categorise infants at birth according to risk for mortality or severe adverse outcome.

METHODS

A retrospective, single centre observational study of infants who received neonatal care from 2011 to 2021. Data were collected on mortality, morbidity and two-year neurodevelopmental outcomes. Each infant was risk categorised utilising the proposed tools in the BAPM (2019) framework. A composite adverse score for either dying or surviving with severe impairment was created.

RESULTS

Four infants born at 22 weeks, 49 at 23 weeks and 105 at 24 weeks of gestation were included. The mortality rate was 23.4 %. Following risk categorisation there were 8 (5.1 %) extremely high risk, 44 (27.8 %) high risk and 106 (67.1 %) moderate risk infants. The rate of dying or surviving with severe impairment for extremely high risk, high risk and moderate risk were 100 %, 88.9 % and 53 % respectively. The proportions with the composite adverse outcome differed significantly according to the risk category (p < 0.001).

CONCLUSIONS

When applying a scoring system to risk categorise infants at birth, high rates of dying or surviving with severe impairment were found in infants born at 22 or 23 weeks of gestation.

Two-year neurodevelopmental outcome in children born extremely preterm: the EPI-DAF study

OBJECTIVE

In 2010, the Dutch practice regarding initiation of active treatment in extremely preterm infants was lowered from 25 completed weeks' to 24 completed weeks' gestation. The nationwide Extremely Preterm Infants - Dutch Analysis on Follow-up Study was set up to provide up-to-date data on neurodevelopmental outcome at 2 years' corrected age (CA) after this guideline change. Design: National cohort study.

PATIENTS

All live born infants between 24^0/7 weeks' and 26^6/7 weeks' gestational age who were 2 years' CA in 2018-2020.

MAIN OUTCOME MEASURE

Impairment at 2 years' CA, based on cognitive score (Bayley-III-NL), neurological examination and neurosensory function.

RESULTS

651 of 991 live born infants (66%) survived to 2 years' CA, with data available for 554 (85%). Overall, 62% had no impairment, 29% mild impairment and 9% moderate-to-severe impairment (further defined as neurodevelopmental impairment, NDI). The percentage of survivors with NDI was comparable for infants born at 24 weeks', 25 weeks' and 26 weeks' gestation. After multivariable analysis, severe brain injury and low maternal education were associated with higher odds on NDI. NDI-free survival was 48%, 67% and 75% in neonatal intensive care unit (NICU)-admitted infants at 24, 25 and 26 weeks' gestation, respectively.

CONCLUSIONS

Lowering the threshold has not been accompanied by a large increase in moderate-to-severely impaired infants. Among live-born and NICU-admitted infants, an increase in NDI-free survival was observed from 24 weeks' to 26 weeks' gestation. This description of a national cohort with high follow-up rates gives an accurate description of the range of outcomes that may occur after extremely preterm birth.

Longitudinal medical needs for periviable NICU survivors

OBJECTIVE

To evaluate the technologies required, medications needed, and early intervention services utilized from discharge to 12 months post-discharge for periviable infants (22 0/7 to 24 6/7 weeks gestational age) followed in a comprehensive NICU follow-up clinic.

STUDY DESIGN

Information regarding medication use, technology requirement, and early intervention services was collected prospectively at one, six, and twelve months after discharge. Neurodevelopmental assessment was completed at 12 months corrected age.

RESULT

69 periviable infants were actively treated and survived to discharge during the study period. 54 infants were enrolled and followed in the comprehensive NICU follow-up clinic. Use of technology and prescribed medications decreased with a 46% reduction of infants requiring ≥1 technology device (74.1% vs. 40.4%, p < 0.01) and 64% reduction in infants requiring ≥1 medication (88.9% vs 31.9%, p < 0.01) 12 months post discharge. There was an increase in early intervention services with 83% of infants receiving services by 12 months post discharge.

CONCLUSION

Technology and medication requirements were high at discharge but notably decreased in the first year after discharge concurrent with increased enrollment in early interventional services. Many periviable infants survive without severe short-term developmental delays.

Perspectives on Resuscitation Decisions at the Margin of Viability among Specialist Newborn Care Providers in Ghana and Ethiopia: A Qualitative Analysis

Background

In high income countries, guidelines exist recommending gestational age thresholds for offering and obligating neonatal resuscitation for extremely preterm infants. In low- and middle- income countries, this approach may be impractical due to limited/inconsistent resource availability and challenges in gestational dating. Scant literature exists on how clinicians in these settings conceptualize viability or make resuscitation decisions for premature infants.

Methods

Qualitative interviews of interprofessional neonatal clinicians were conducted in Kumasi, Ghana, at Komfo Anokye Teaching Hospital and Suntreso Government Hospital, and in Addis Ababa, Ethiopia, at St. Paul’s Hospital Millennium Medical College. Transcribed interviews were coded through the constant comparative method.

Results

Three discrete major themes were identified. The principal theme was a respect for all life, regardless of the likelihood for survival. This sense of duty arose from a duty to God, a duty to the patient, and a duty intrinsic to one’s role as a medical provider. The duty to resuscitate was balanced by the second major theme, an acceptance of futility for many premature infants. Lack of resources, inappropriate staffing, and historically high local neonatal mortality rates were often described. The third theme was a desire to meet global standards of newborn care, including having resources to adopt the 22–25-week thresholds used in high income countries and being able to consistently provide life-saving measures to premature infants.

Conclusions

Neonatal clinicians in Ghana and Ethiopia described respect for all life and desire to meet global standards of newborn care, balanced with an awareness of futility based on local resource limitations. In both countries, clinicians highlighted how wide variations in regional survival outcomes limited their ability to rely on structured resuscitation guidelines based on gestational age and/or birthweight.

Global incidence of intraventricular hemorrhage among extremely preterm infants: a systematic literature review

OBJECTIVES

To conduct a systematic literature review to evaluate the global incidence of intraventricular hemorrhage grade 2-4 among extremely preterm infants.

METHODS

We performed searches in MEDLINE and Embase for intraventricular hemorrhage and prematurity cited in English language observational studies published from May 2006 to October 2017. Included studies analyzed data from infants born at ≤28 weeks' gestational age and reported on intraventricular hemorrhage epidemiology.

RESULTS

Ninety-eight eligible studies encompassed 39 articles from Europe, 31 from North America, 25 from Asia, five from Oceania, and none from Africa or South America; both Europe and North America were included in two publications. The reported global incidence range of intraventricular hemorrhage grade 3-4 was 5-52% (Europe: 5-52%; North America: 8-22%; Asia: 5-36%; Oceania: 8-13%). When only population-based studies were included, the incidence range of intraventricular hemorrhage grade 3-4 was 6-22%. The incidence range of intraventricular hemorrhage grade 2 was infrequently documented and ranged from 5-19% (including population-based studies). The incidence of intraventricular hemorrhage was generally inversely related to gestational age.

CONCLUSIONS

Intraventricular hemorrhage is a frequent complication of extremely preterm birth. Intraventricular hemorrhage incidence range varies by region, and the global incidence of intraventricular hemorrhage grade 2 is not well documented.

Global prevalence of long-term neurodevelopmental impairment following extremely preterm birth: a systematic literature review

Objective

Neurodevelopmental impairment (NDI) is a major complication of extreme prematurity. This systematic review was conducted to summarize the worldwide long-term prevalence of NDI associated with extreme prematurity.

Methods

Embase and MEDLINE databases were searched for epidemiologic and observational/real-world studies, published in English between 2011 and 2016, reporting long-term prevalence of NDI (occurring from 1 year) among extremely preterm infants born at gestational age (GA) ≤28 weeks.

Results

Of 2406 articles identified through searches, 69 met the protocol NDI definition (24 North America, 25 Europe, 20 Rest of World). Prevalence of any severity NDI in North America was 8%–59% at 18 months to 2 years, and 11%–37% at 2–5 years; prevalence of moderate NDI in Europe was 10%–13% at 18 months to 2 years, 3% at 2–5 years, and 9%–19% at ≥5 years; prevalence of any NDI in Rest of World was 15%–61% at 18 months to 2 years, and 42% at 2–5 years (no North America/Rest of World studies reported any NDI at ≥5 years). A trend toward higher prevalence of NDI with lower GA at birth was observed.

Conclusions

Extreme prematurity has a significant long-term worldwide impact on neurodevelopmental outcomes.

Altered Right Ventricular Filling at Four-dimensional Flow MRI in Young Adults Born Prematurely

Purpose

To use four-dimensional (4D) flow MRI to measure intraventricular flow in young adults who were born prematurely to investigate mechanisms that may account for increased heart failure risk in this population.

Materials and Methods

In this secondary analysis of a prospective study, a total of 56 young adults participated in an observational cardiac 4D flow MRI study from 2016 to 2020. There were 35 participants who had been born moderately to extremely prematurely (birth weight <1500 g or gestational age ≤32 weeks; 23 women; mean age, 26 years ± 4) and 21 term-born participants (11 women; mean age, 25 years ± 3). Participants underwent cardiac MRI, including cine cardiac structure and function assessment, as well as 4D flow MRI. In each ventricle, normalized kinetic energy (KE/end diastolic volume) and flow through the atrioventricular valve were computed and compared between term-born and preterm participants at systolic and diastolic (early diastolic filling rate [E wave] and late diastolic filling [atrial contraction] rate [A wave]) time points by using Wilcoxon rank-sum tests.

Results

Preterm-born participants had lower right ventricular (RV) E wave/A wave (E/A) KE ratios (2.4 ± 1.7 vs 3.5 ± 1.4; P <.01) and lower E/A peak filling rate ratios (computed from RV volume-time curves; 2.3 ± 1.3 vs 3.5 ± 2.5; P = .03). Additionally, viscous energy dissipation was increased during systole (5.7 µW/mL ± 3.0 vs 4.2 µW/mL ± 1.6; P = .03), increased during late diastole (3.9 µW/mL ± 4.0 vs 2.2 µW/mL ± 1.6; P = .03), and summed over the cardiac cycle (2.4 µJ/mL ± 1.0 vs 1.9 µJ/mL ± 0.6; P = .02) in preterm relative to term participants.

Conclusion

These results suggest that RV diastolic filling is altered in young adults who were born moderately to severely prematurely.Supplemental material is available for this article. Keywords: Adults, Cardiac, Comparative Studies, MR-Imaging, Right Ventricle © RSNA, 2021.

Sildenafil administration improves right ventricular function on 4D flow MRI in young adults born premature

Extreme preterm birth conveys an elevated risk of heart failure by young adulthood. Smaller biventricular chamber size, diastolic dysfunction, and pulmonary hypertension may contribute to reduced ventricular-vascular coupling. However, how hemodynamic manipulations may affect right ventricular (RV) function and coupling remains unknown. As a pilot study, 4D flow MRI was used to assess the effect of afterload reduction and heart rate reduction on cardiac hemodynamics and function. Young adults born premature were administered sildenafil (a pulmonary vasodilator) and metoprolol (a β blocker) on separate days, and MRI with 4D flow completed before and after each drug administration. Endpoints include cardiac index (CI), direct flow fractions, and ventricular kinetic energy including E/A wave kinetic energy ratio. Sildenafil resulted in a median CI increase of 0.24 L/min/m2 (P = 0.02), mediated through both an increase in heart rate (HR) and stroke volume. Although RV ejection fraction improved only modestly, there was a significant increase (4% of end diastolic volume) in RV direct flow fraction (P = 0.04), consistent with hemodynamic improvement. Metoprolol administration resulted in a 5-beats/min median decrease in HR (P = 0.01), a 0.37 L/min/m2 median decrease in CI (P = 0.04), and a reduction in time-averaged kinetic energy (KE) in both ventricles (P < 0.01), despite increased RV diastolic E/A KE ratio (P = 0.04). Despite reduced right atrial workload, metoprolol significantly depressed overall cardiac systolic function. Sildenafil, however, increased CI and improved RV function, as quantified by the direct flow fraction. The preterm heart appears dependent on HR but sensitive to RV afterload manipulations.NEW & NOTEWORTHY We assessed the effect of right ventricular afterload reduction with sildenafil and heart rate reduction with metoprolol on cardiac hemodynamics and function in young adults born premature using 4D flow MRI. Metoprolol depressed cardiac function, whereas sildenafil improved cardiac function including right ventricular direct flow fraction by 4D flow, consistent with hemodynamic improvement. This suggests that the preterm heart is dependent on heart rate and sensitive to right ventricular afterload changes.

Dynamic FDG PET Imaging to Probe for Cardiac Metabolic Remodeling in Adults Born Premature

Individuals born very premature have an increased cardiometabolic and heart failure risk. While the structural differences of the preterm heart are now well-described, metabolic insights into the physiologic mechanisms underpinning this risk are needed. Here, we used dynamic fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET-MRI) in young adults born term and preterm during normoxic (N = 28 preterm; 18 term) and hypoxic exposure (12% O2; N = 26 preterm; 17 term) to measure the myocardial metabolic rate of glucose (MMRglc) in young adults born term (N = 18) and preterm (N = 32), hypothesizing that young adults born preterm would have higher rates of MMRglc under normoxic conditions and a reduced ability to augment glucose metabolism under hypoxic conditions. MMRglc was calculated from the myocardial and blood pool time-activity curves by fitting the measured activities to the 3-compartment model of FDG kinetics. MMRglc was similar at rest between term and preterm subjects, and decreased during hypoxia exposure in both groups (p = 0.02 for MMRglc hypoxia effect). There were no differences observed between groups in the metabolic response to hypoxia, either globally (serum glucose and lactate measures) or within the myocardium. Thus, we did not find evidence of altered myocardial metabolism in the otherwise healthy preterm-born adult. However, whether subtle changes in myocardial metabolism may preceed or predict heart failure in this population remains to be determined.

Transcutaneous carbon dioxide pattern and trend over time in preterm infants

BACKGROUND

Chronic lung disease remains a burden for extremely preterm infants. The changes in ventilation over time and optimal ventilatory management remains unknown. Newer, non-invasive technologies provide insight into these patterns.

METHODS

This single-center prospective cohort study enrolled infants ≤32 0/7 weeks. We obtained epochs of transcutaneous carbon dioxide (TcCO₂) measurements twice each week to describe the pattern of hypercarbia throughout their hospitalization.

RESULTS

Patterns of hypercarbia varied based on birth gestational age and post-menstrual age (PMA) (p = 0.03), regardless of respiratory support. Infants receiving the most respiratory support had values 16-21 mmHg higher than those on room air (p < 0.001). Infants born at the youngest gestational ages had the greatest total change but the rate of change was slower (p = 0.049) compared to infants born at later gestational ages. All infants had TcCO₂ values stabilize by 31-33 weeks PMA, when values were not significantly different compared to discharge. No rebound was observed when infants weaned off invasive support.

CONCLUSIONS

Hypercarbia improves as infants approached 31-33 weeks PMA. Hypercarbia was the highest in the most immature infants and improved with age and growth despite weaning respiratory support.

IMPACT

This study describes the evolution of hypercarbia as very preterm infants grow and develop. The pattern of ventilation is significantly different depending on the gestational age at birth and post-menstrual age. Average transcutaneous carbon dioxide (TCO₂) decreased over time as infants became more mature despite weaning respiratory support. This improvement was most significant in infants born at the lowest gestational ages.

Developmental Trajectories in Very Preterm Born Children Up to 8 Years: A Longitudinal Cohort Study

Aim: Long-term outcome data in preterm children is often limited to cross-sectional measurement of neurodevelopmental impairment (NDI) at the corrected age of 24-36 months. However, impairments may only become overt during childhood or resolve with time, and individual trajectories in outcome over time may vary. The primary aim of this study was to describe NDI in very preterm born children at three subsequent ages of 2, 5, and 8 years of age. As a secondary aim, a longitudinal analysis was performed on the individual longitudinal trajectories in NDI from 2 to 8 years of age. Methods: Single-center prospective cohort study including children born between 1990 and 2011 below 30 weeks' gestation and followed into 2019. The outcome measurement was NDI assessed at 2, 5, and 8 years of age. NDI is a composite score that includes cognitive, neurological, visual, and auditory functions, in which problems were categorized as none, mild, moderate, or severe. Cognitive function measured as total DQ/IQ score was assessed by standardized psychometric tests. Neurological, visual, and auditory functions were assessed by the neonatologist. Results: In total, 921 children were eligible for follow-up, of whom 726 (79%) children were assessed. No NDI was seen in 54, 54, and 62%, mild NDI was seen in 31, 36, and 30%, and moderate-to-severe NDI was seen in 15, 9.2, and 8.6% of the children at 2, 5, and 8 years, respectively. From 2 to 8 years, 63% of the children remained in the same NDI category, 20% of the children improved to a better NDI category, and 17% deteriorated toward a worse NDI category. No differences were found in baseline characteristics of infants that improved or deteriorated. Extreme prematurity, male gender and low parental education were associated with worse NDI status at all time points. Although we observed considerable individual variation over time in NDI status, the course of the trajectories in NDI were not associated with gestation, gender, and parental education. Conclusions: Continued follow-up until school life is essential in order to provide optimal and individually focused referrals and care when needed.

Paradoxes of professional autonomy: a qualitative study of U.S. neonatologists from 1978-2017

The professional autonomy of physicians often requires they take responsibility for life and death decisions, but they must also find ways to avoid bearing the full weight of such decisions. We conducted in-person, semi-structured interviews with neonatologists (n = 20) in four waves between 1978 and 2017 in a single Midwestern U.S. city. Using open coding analysis, we found over time that neonatologists described changes in their sense of professional autonomy and responsibility for decisions with life and death consequences. Through the early 1990s, as neonatology consolidated as a profession, physicians simultaneously enjoyed high levels of professional discretion and responsibility and were often constrained by bioethics and the law. By 2010s, high involvement of parents and collaboration with multiple subspecialties diffused the burden felt by individual practitioners, but neonatology's professional autonomy was correlatively diminished. Decision-making in the NICU over four decades reveal a complex relationship between the professional autonomy of neonatologist and the burden they bear, with some instances of ceding autonomy as a protective measure and other situations of unwelcomed erosion of professional autonomy that neonatologists see as complicating provision of care.

Aspects of the assessment and management of pharyngoesophageal dysphagia

Swallowing complaints are common and may have significant consequences for nutrition and pulmonary health. Etiology varies and different aspects of the deglutitive system may be affected. A thorough assessment from the oral cavity to the stomach will provide physiologic information that enables specific targeted management plans to be devised. Although the swallow trajectory bridges anatomic areas, there has previously been a tendency to compartmentalize assessment and treatment by arbitrary anatomic boundaries. It is now clear that this approach fails to appreciate the complexity of swallow mechanics and that systems (oral, pharyngeal, esophageal, and pulmonary) are intertwined and codependent. Swallowing specialists from different backgrounds and with complementary skill sets form a multidisciplinary team that can provide insight and address multiple areas of management. With the advent of new tools for instrumental evaluation, such as manometry, targeted rehabilitative strategies can be informed by physiology, increased in precision and breadth, and assessed quantitatively. Surgical approaches have evolved toward endoscopic techniques, and food technology is expanding options in dietary management. The multidisciplinary team is core to managing this varied and often neglected patient population. This review is for clinicians treating swallowing disorders and will explore the selected aspects of the assessment and management of pharyngoesophageal swallowing disorders.

Bioethical Decisions in Neonatal Intensive Care: Neonatologists' Self-Reported Practices in Greek NICUs

This study presents, for the first time, empirical data on practices regarding bioethical decision-making in treatment of preterm and ill newborns in Greece. The aim of the study was to: (a) record self-reported practices and involvement of Greek physicians in decisions of withholding and withdrawing neonatal intensive care, and (b) explore the implication of cultural, ethical, and professional parameters in decision-making. Methods: 71 physicians, employed fulltime in all public Neonatal Intensive Care Units (NICUs) (n = 17) in Greece, completed an anonymous questionnaire between May 2009 and May 2011. Results: One-third of the physicians in our sample admitted that they have, at least once in the past, decided the limitation of intensive care of a newborn close to death (37.7%) and/or a newborn with unfavorable neurological prognosis (30.8%). The higher the physicians’ support towards the value of quality of human life, the more probable it was that they had taken a decision to withhold or withdraw neonatal intensive care (p < 0.05). Conclusions: Our research shows that Greek NICU physicians report considerably lower levels of ethical decision-making regarding preterm and ill newborns compared to their counterparts in other European countries. Clinical practices and attitudes towards ethical decision-making appear to be influenced mainly by the Greek physicians’ values.

Global incidence of bronchopulmonary dysplasia among extremely preterm infants: a systematic literature review

BACKGROUND

Infants born extremely preterm (<28 weeks gestational age (GA)) face a high risk of neonatal mortality. Bronchopulmonary dysplasia (BPD) is the most common morbidity of prematurity.

OBJECTIVE

To evaluate the global incidence of BPD among infants born extremely preterm.

DESIGN

A systematic review of the literature was conducted in Embase and MEDLINE (via PubMed) using a prespecified search strategy for BPD and prematurity. Observational studies published in English between 16 May 2006 and 16 October 2017 reporting on the occurrence of BPD in infants born <28 weeks GA were included.

RESULTS

Literature searches yielded 103 eligible studies encompassing 37 publications from Europe, 38 publications from North America, two publications from Europe and North America, 19 publications from Asia, one publication from Asia and North America, six publications from Oceania, and zero publications from Africa or South America. The reported global incidence range of BPD was 10-89% (10-73% in Europe, 18-89% in North America, 18-82% in Asia, and 30-62% in Oceania). When only population-based observational studies that defined BPD as requiring supplemental oxygen at 36 weeks postmenstrual age were included, the global incidence range of BPD was 17-75%. The wide range of incidences reflected interstudy differences in GA (which was inversely related to BPD incidence), birthweight, and survival rates across populations and institutions.

CONCLUSIONS

BPD is a common health morbidity occurring with extremely preterm birth. Further study of factors that impact incidence, aside from low GA, may help to elucidate modifiable risks.

Neurodevelopmental Outcomes in Infants With Birth Weight ≤500 g at 3 Years of Age

OBJECTIVES

To determine neurodevelopmental outcomes at 3 years of age in children born with a birth weight (BW) of ≤500 g.

METHODS

Infants who were born with a BW of ≤500 g from 2003 to 2012 in the Neonatal Research Network of Japan and survived to discharge from the NICU were eligible in this study. The study population consisted of 460 children (56.7% of 811 surviving infants) who were evaluated at 36 to 42 months of age. Neurodevelopmental impairment (NDI) was defined as having cerebral palsy, visual impairment, hearing impairment, or a developmental quotient score of <70.

RESULTS

The overall proportion of NDI was 59.1% (95% confidence interval [CI]: 54.6%-63.5%). The trend revealed no significant change during the study period. In a multivariate modified Poisson regression analysis, NDI was associated with severe intraventricular hemorrhage (adjusted risk ratio [RR]: 1.42; 95% CI: 1.19-1.68; P < .01), cystic periventricular leukomalacia (adjusted RR: 1.40; 95% CI: 1.13-1.73; P < .01), severe necrotizing enterocolitis (adjusted RR: 1.31; 95% CI: 1.07-1.60; P < .01), surgical ligation for patent ductus arteriosus (adjusted RR: 1.29; 95% CI: 1.09-1.54; P < .01), and male sex (adjusted RR: 1.19; 95% CI: 1.01-2.40; P = .04).

CONCLUSIONS

This cohort showed that neurodevelopmental outcomes of infants with a BW of ≤500 g have not improved from 2003 to 2012. Multivariate analysis revealed that severe intracranial hemorrhage and cystic periventricular leukomalacia were the strongest risk factors for NDIs. Our data suggested that measures aimed at reducing neurologic morbidities will be important for improving outcomes of infants with a BW of ≤500 g.

Functional morphometry for the estimation of the alveolar surface area in prematurely-born infants

Conventionally, the alveolar surface area (S_A) has been measured by using post-mortem morphometry. Such studies have highlighted that S_A in prematurely-born infants is markedly smaller when compared to term-born infants as a result of postnatal impairment or arrest of alveolar development. We herein explore how, non-invasive measurements of the ventilation/perfusion ratio (V_A/Q) can be used to estimate S_A in prematurely-born surviving, convalescent infants. We also compare S_A in prematurely-born infants measured at term-corrected age, to term-born infants using previously published datasets of V_A/Q. Fick's first law of diffusion is employed for the conversion of V_A/Q measurements to S_A values after correcting for differences in pulmonary perfusion, thickness of the respiratory membrane and alveolar-arterial gradient. We report that S_A is fivefold smaller in prematurely-born compared to term-born infants. We conclude that non-invasive measurements of V_A/Q can be used for the functional estimation of S_A which could, in turn, be used as a future outcome measure in respiratory studies of prematurely-born infants.

Neurodevelopmental considerations in surgical necrotizing enterocolitis

The majority of surviving infants with surgical necrotizing enterocolitis (NEC) will have some degree of neurodevelopmental impairment. The impact of specific medial and surgical treatments for infants with severe NEC remains largely unknown but is being actively investigated. It is incumbent upon all providers caring for these infants to continue to focus on long term neurodevelopmental outcomes and to develop more widespread methods of neurodevelopmental assessment.

Rates of early intervention services in children born extremely preterm/extremely low birthweight

AIM

To determine the rates of early intervention (EI) service use in extremely preterm (EP, <28 weeks' gestation) or extremely low birthweight (ELBW, <1000 g) infants between 1991 and 2013, and identify biological or socio-economic factors associated with receiving EI.

METHODS

Participants comprised consecutive EP or ELBW survivors born in 1991-1992, 1997 or 2005 in Victoria, Australia, and randomly selected, matched term-born controls. The main outcome measure was parent-reported EI participation up to 8 years of age. Neurodevelopmental outcomes and socio-economic risk factors were compared with EI participation to identify associations among the preterm groups.

RESULTS

The rates of EI were higher in the preterm groups than the control groups overall (odds ratio 4.29, 95% confidence interval 3.28, 5.59, P < 0.001), and the rates of EI rose significantly over time - from 42% in the 1991-1992 preterm cohort to 64% in the 2005 preterm cohort. Among the preterm groups, post-natal corticosteroid therapy, cystic periventricular leukomalacia and surgery in the newborn period were all independently associated with increased odds of receiving EI. Increased severity of disability was associated with higher rates of EI. The majority (95%) of preterm children with a physical impairment received EI, compared with only 73% of children with a cognitive impairment alone. EI participation rates were independent of social risk.

CONCLUSION

EI participation is high in the EP population, and rates of EI use have increased over time. Contrary to previous reports, social risk factors were not found to be associated with EI use.

Changes in survival and neurodevelopmental outcomes of infants born at <25 weeks' gestation: a retrospective observational study in tertiary centres in Japan

OBJECTIVE

To evaluate changes in the outcomes of infants born at <25 weeks' gestation in the past decade.

DESIGN

Retrospective observational study.

SETTINGS

A multicentre database of the Neonatal Research Network, Japan.

PATIENTS

A total of 3318 infants born at 22-24 weeks' gestation between periods 1 (2003-2007) and 2 (2008-2012) from 52 tertiary centres.

MAIN OUTCOME MEASURES

We compared death and neurodevelopmental impairments (NDIs) at 3 years of age, including cerebral palsy (CP), visual impairments (VIs), hearing impairments (HIs) and the developmental quotient (DQ) of the Kyoto Scale of Psychological Development test <70, between two periods using multivariate logistic regression analyses adjusted for the centre, gender, multiple gestation, maternal age, caesarean delivery, antenatal steroid use, pregnancy-related hypertension, clinical chorioamnionitis, congenital anomalies and birth weight.

RESULTS

A total of 496/1479 infants (34%) in period 1 and 467/1839 (25%) in period 2 died by 3 years of age (adjusted OR 0.70, 95% CIs 0.59 to 0.83). Follow-up data were collected from 631 infants (64% of survivors) in period 1 and 832 (61% of survivors) in period 2. The proportions of CP with Gross Motor Function Classification System ≥2, VI and HI in the infants evaluated were lower, while that of DQ <70 was higher in period 2 than in period 1. Using multiple imputations to account for missing data, death or NDI decreased from 54% in period 1 to 47% in period 2 (0.83, 0.71 to 0.97). Significant decreases were observed in death or CP (0.65, 0.55 to 0.76), death or VI (0.59, 0.50 to 0.69) and death or HI (0.69, 0.58 to 0.81), but not in death or DQ <70 (0.91, 0.78 to 1.06).

CONCLUSION

Along with improved survival, CP, VI and HI, but not cognitive impairments decreased in infants born at <25 weeks' gestation between the two periods examined in the last decade. Further strategies are needed to reduce cognitive impairments in these infants.

Adults born preterm: a review of general health and system-specific outcomes

In this review of 126 publications, we report that an overwhelming majority of adults born at preterm gestations remain healthy and well. However, a small, but a significant fraction of them remain at higher risk for neurological, personality and behavioural abnormalities, cardio-pulmonary functional limitations, systemic hypertension and metabolic syndrome compared to their term-born counterparts. The magnitude of increased risk differed across organ systems and varied across reports. The risks were proportional to the degree of prematurity at birth and seemed to occur more frequently among preterm infants born in the final two decades of the 20th century and later. These findings have considerable public health and clinical practice relevance.

CONCLUSION

Preterm birth needs to be considered a chronic condition, with a slight increase in the risk for long-term morbidities among adults born preterm. Therefore, obtaining a history of gestational age and weight at birth should be a routine part of care for patients of all age groups.

Determinants of developmental outcomes in a very preterm Canadian cohort

OBJECTIVES

Identify determinants of neurodevelopmental outcome in preterm children.

METHODS

Prospective national cohort study of children born between 2009 and 2011 at <29 weeks gestational age, admitted to one of 28 Canadian neonatal intensive care units and assessed at a Canadian Neonatal Follow-up Network site at 21 months corrected age for cerebral palsy (CP), visual, hearing and developmental status using the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III). Stepwise regression analyses evaluated the effect of (1) prenatal and neonatal characteristics, (2) admission severity of illness, (3) major neonatal morbidities, (4) neonatal neuroimaging abnormalities, and (5) site on neurodevelopmental impairment (NDI) (Bayley-III score < 85, any CP, visual or hearing impairment), significant neurodevelopmental impairment (sNDI) (Bayley-III < 70, severe CP, blind or hearing aided and sNDI or death.

RESULTS

Of the 3700 admissions without severe congenital anomalies, 84% survived to discharge and of the 2340 admissions, 46% (IQR site variation 38%-51%) had a NDI, 17% (11%-23%) had a sNDI, 6.4% (3.1%-8.6%) had CP, 2.6% (2.5%-13.3%) had hearing aids or cochlear implants and 1.6% (0%-3.1%) had a bilateral visual impairment. Bayley-III composite scores of <70 for cognitive, language and motor domains were 3.3%, 10.9% and 6.7%, respectively. Gestational age, sex, outborn, illness severity, bronchopulmonary dysplasia, necrotising enterocolitis, late-onset sepsis, retinopathy of prematurity, abnormal neuroimaging and site were significantly associated with NDI or sNDI. Site variation ORs for NDI, sNDI and sNDI/death ranged from 0.3-4.3, 0.04-3.5 and 0.12-1.96, respectively.

CONCLUSION

Most preterm survivors are free of sNDI. The risk factors, including site, associated with neurodevelopmental status suggest opportunities for improving outcomes.

Trends in Overall Mortality, and Timing and Cause of Death among Extremely Preterm Infants near the Limit of Viability

Objective

To investigate the trends in mortality, as well as in the timing and cause of death, among extremely preterm infants at the limit of viability, and thus to identify the clinical factors that contribute to decreased mortality.

Methods

We retrospectively reviewed the medical records of 382 infants born at 23–26 weeks’ gestation; 124 of the infants were born between 2001 and 2005 (period I) and 258 were born between 2006 and 2011 (period II). We stratified the infants into two subgroups–“23–24 weeks” and “25–26 weeks”–and retrospectively analyzed the clinical characteristics and mortality in each group, as well as the timing and cause of death. Univariate and multivariate logistic regression analyses were done to identify the clinical factors associated with mortality.

Results

The overall mortality rate in period II was 16.7% (43/258), which was significantly lower than that in period I (30.6%; 38/124). For overall cause of death, there were significantly fewer deaths due to sepsis (2.4% [6/258] vs. 8.1% [10/124], respectively) and air-leak syndrome (0.8% [2/258] vs. 4.8% (6/124), respectively) during period II than during period I. Among the clinical factors of time period, 1-and 5-min Apgar score, antenatal steroid identified significant by univariate analyses. 5-min Apgar score and antenatal steroid use were significantly associated with mortality in multivariate analyses.

Conclusion

Improved mortality rate attributable to fewer deaths due to sepsis and air leak syndrome in the infants with 23–26 weeks’ gestation was associated with higher 5-minute Apgar score and more antenatal steroid use.

Monitoring Cerebral Oxygenation in Neonates: An Update

Cerebral oxygenation is not always reflected by systemic arterial oxygenation. Therefore, regional cerebral oxygen saturation (rScO₂) monitoring with near-infrared spectroscopy (NIRS) is of added value in neonatal intensive care. rScO₂ represents oxygen supply to the brain, while cerebral fractional tissue oxygen extraction, which is the ratio between rScO₂ and systemic arterial oxygen saturation, reflects cerebral oxygen utilization. The balance between oxygen supply and utilization provides insight in neonatal cerebral (patho-)physiology. This review highlights the potential and limitations of cerebral oxygenation monitoring with NIRS in the neonatal intensive care unit.

Antenatal Exposure to Magnesium Sulfate Is Associated with Reduced Cerebellar Hemorrhage in Preterm Newborns

OBJECTIVE

To determine the association of antenatal magnesium sulfate with cerebellar hemorrhage in a prospective cohort of premature newborns evaluated by magnetic resonance imaging (MRI).

STUDY DESIGN

Cross-sectional analysis of baseline characteristics from a prospective cohort of preterm newborns (<33 weeks gestation) evaluated with 3T-MRI shortly after birth. Exclusion criteria were clinical evidence of a congenital syndrome, congenital infection, or clinical status too unstable for transport to MRI. Antenatal magnesium sulfate exposure was abstracted from the medical records and the indication was classified as obstetric or neuroprotection. Two pediatric neuroradiologists, blinded to the clinical history, scored axial T2-weighted and iron susceptibility MRI sequences for cerebellar hemorrhage. The association of antenatal magnesium sulfate with cerebellar hemorrhage was evaluated using multivariable logistic regression, adjusting for postmenstrual age at MRI and known predictors of cerebellar hemorrhage.

RESULTS

Cerebellar hemorrhage was present in 27 of 73 newborns (37%) imaged at a mean ± SD postmenstrual age of 32.4 ± 2 weeks. Antenatal magnesium sulfate exposure was associated with a significantly reduced risk of cerebellar hemorrhage. Adjusting for postmenstrual age at MRI, and predictors of cerebellar hemorrhage, antenatal magnesium sulfate was independently associated in our cohort with decreased cerebellar hemorrhage (OR, 0.18; 95% CI, 0.049-0.65; P = .009).

CONCLUSION

Antenatal magnesium sulfate exposure is independently associated with a decreased risk of MRI-detected cerebellar hemorrhage in premature newborns, which could explain some of the reported neuroprotective effects of magnesium sulfate.