Diuresis-led volume replacement strategy in extremely low birth weight infants.

AIM: In extremely low birth weight infants, fluid overload has been associated with bronchopulmonary dysplasia and death. Excessive weight loss may increase the risk of meconium obstruction and intestinal perforation. As these infants display oliguria followed by polyuria, we embarked on a diuresis-led volume replacement strategy as of January 2020. METHODS: This single-centre analysis presents data of infants <1000 g birth weight surviving for more than 3 days admitted 2017-2019 (n = 217, daily volume increase) versus 2020-2022 (n = 2022, diuresis-led volume replacement). RESULTS: The second cohort had lower gestational age (median [interquartile range]: 253/7 [243/7-264/7] vs. 263/7 [251/7-282/7] weeks), less antenatal steroids (58% vs. 69%), more indomethacin (66% vs. 47%) and higher initial diuresis (5.6 [4.9-6.8] vs. 4.8 [4.2-5.5] mL/kg/h) but did not differ by relative weight loss at Day 7 of life. Employing binary logistic regression with gestational age, antenatal steroids and indomethacin as covariates, the cohorts did not differ by rates of patent ductus arteriosus, abdominal surgery or severe retinopathy of prematurity, while there were significant declines in sepsis (from 32% to 19%), bronchopulmonary dysplasia (from 26% to 23%) and mortality (from 13% to 7%). CONCLUSION: Diuresis-led volume replacement appears to be safe and maybe beneficial.

Next-generation phenotyping integrated in a national framework for patients with ultrarare disorders improves genetic diagnostics and yields new molecular findings.

Individuals with ultrarare disorders pose a structural challenge for healthcare systems since expert clinical knowledge is required to establish diagnoses. In TRANSLATE NAMSE, a 3-year prospective study, we evaluated a novel diagnostic concept based on multidisciplinary expertise in Germany. Here we present the systematic investigation of the phenotypic and molecular genetic data of 1,577 patients who had undergone exome sequencing and were partially analyzed with next-generation phenotyping approaches. Molecular genetic diagnoses were established in 32% of the patients totaling 370 distinct molecular genetic causes, most with prevalence below 1:50,000. During the diagnostic process, 34 novel and 23 candidate genotype-phenotype associations were identified, mainly in individuals with neurodevelopmental disorders. Sequencing data of the subcohort that consented to computer-assisted analysis of their facial images with GestaltMatcher could be prioritized more efficiently compared with approaches based solely on clinical features and molecular scores. Our study demonstrates the synergy of using next-generation sequencing and phenotyping for diagnosing ultrarare diseases in routine healthcare and discovering novel etiologies by multidisciplinary teams.

Bilirubin Exerts Protective Effects on Alveolar Type II Pneumocytes in an In Vitro Model of Oxidative Stress.

Newborn infants face a rapid surge of oxygen and a more protracted rise of unconjugated bilirubin after birth. Bilirubin has a strong antioxidant capacity by scavenging free radicals, but it also exerts direct toxicity. This study investigates whether cultured rat alveolar epithelial cells type II (AEC II) react differently to bilirubin under different oxygen concentrations. The toxic threshold concentration of bilirubin was narrowed down by means of a cell viability test. Subsequent analyses of bilirubin effects under 5% oxygen and 80% oxygen compared to 21% oxygen, as well as pretreatment with bilirubin after 4 h and 24 h of incubation, were performed to determine the induction of apoptosis and the gene expression of associated transcripts of cell death, proliferation, and redox-sensitive transcription factors. Oxidative stress led to an increased rate of cell death and induced transcripts of redox-sensitive signaling pathways. At a non-cytotoxic concentration of 400 nm, bilirubin attenuated oxidative stress-induced responses and possibly mediated cellular antioxidant defense by influencing Nrf2/Hif1α- and NFκB-mediated signaling pathways. In conclusion, the study demonstrates that rat AEC II cells are protected from oxidative stress-induced impairment by low-dose bilirubin.

The gut microbiome, resistome, and mycobiome in preterm newborn infants and mouse pups: lack of lasting effects by antimicrobial therapy or probiotic prophylaxis.

BACKGROUND: Enhancing our understanding of the underlying influences of medical interventions on the microbiome, resistome and mycobiome of preterm born infants holds significant potential for advancing infection prevention and treatment strategies. We conducted a prospective quasi-intervention study to better understand how antibiotics, and probiotics, and other medical factors influence the gut development of preterm infants. A controlled neonatal mice model was conducted in parallel, designed to closely reflect and predict exposures. Preterm infants and neonatal mice were stratified into four groups: antibiotics only, probiotics only, antibiotics followed by probiotics, and none of these interventions. Stool samples from both preterm infants and neonatal mice were collected at varying time points and analyzed by 16 S rRNA amplicon sequencing, ITS amplicon sequencing and whole genome shotgun sequencing. RESULTS: The human infant microbiomes showed an unexpectedly high degree of heterogeneity. Little impact from medical exposure (antibiotics/probiotics) was observed on the strain patterns, however, Bifidobacterium bifidum was found more abundant after exposure to probiotics, regardless of prior antibiotic administration. Twenty-seven antibiotic resistant genes were identified in the resistome. High intra-variability was evident within the different treatment groups. Lastly, we found significant effects of antibiotics and probiotics on the mycobiome but not on the microbiome and resistome of preterm infants. CONCLUSIONS: Although our analyses showed transient effects, these results provide positive motivation to continue the research on the effects of medical interventions on the microbiome, resistome and mycobiome of preterm infants.

Oxygen and HIF1α-dependent SDF1 expression in primary astrocytes.

In the naturally hypoxic in utero fetal environment of preterm infants, oxygen and oxygen-sensitive signaling pathways play an important role in brain development, with hypoxia-inducible factor-1α (HIF1α) being an important regulator. Early exposure to nonphysiological high oxygen concentrations by birth in room can induce HIF1α degradation and may affect neuronal and glial development. This involves the dysregulation of astroglial maturation and function, which in turn might contribute to oxygen-induced brain injury. In this study, we investigated the effects of early high oxygen exposure on astroglial maturation and, specifically, on astroglial stromal cell-derived factor 1 (SDF1) expression in vivo and in vitro. In our neonatal mouse model of hyperoxia preterm birth brain injury in vivo, high oxygen exposure affected astroglial development and cortical SDF1 expression. These results were further supported by reduced Sdf1 expression, impaired proliferation, decreased total cell number, and altered expression of astroglial markers in astrocytes in primary cultures grown under high oxygen conditions. Moreover, to mimic the naturally hypoxic in utero fetal environment, astroglial Sdf1 expression was increased after low oxygen exposure in vitro, which appears to be regulated by HIF1α activity. Additionally, the knockdown of Hif1α revealed HIF1α-dependent Sdf1 expression in vitro. Our results indicate HIF1α and oxygen-dependent chemokine expression in primary astrocytes and highlight the importance of oxygen conditions for brain development.

The Finnegan Score for Neonatal Opioid Withdrawal Revisited With Routine Electronic Data: Retrospective Study.

Background: The severity of neonatal abstinence syndrome (NAS) may be assessed with the Finnegan score (FS). Since the FS is laborious and subjective, alternative ways of assessment may improve quality of care. Objective: In this pilot study, we examined associations between the FS and routine monitoring data obtained from the electronic health record system. Methods: The study included 205 neonates with NAS after intrauterine (n=23) or postnatal opioid exposure (n=182). Routine monitoring data were analyzed at 60±10 minutes (t-1) and 120±10 minutes (t-2) before each FS assessment. Within each time period, the mean for each variable was calculated. Readings were also normalized to individual baseline data for each patient and parameter. Mixed effects models were used to assess the effect of different variables. Results: Plots of vital parameters against the FS showed heavily scattered data. When controlling for several variables, the best-performing mixed effects model displayed significant effects of individual baseline-controlled mean heart rate (estimate 0.04, 95% CI 0.02-0.07) and arterial blood pressure (estimate 0.05, 95% CI 0.01-0.08) at t-1 with a goodness of fit (R2m) of 0.11. Conclusions: Routine electronic data can be extracted and analyzed for their correlation with FS data. Mixed effects models show small but significant effects after normalizing vital parameters to individual baselines.

Trends in Apgar scores and umbilical artery pH: a population-based cohort study on 10,696,831 live births in Germany, 2008-2022.

Low Apgar scores and low umbilical arterial (UA) blood pH are considered indicators of adverse perinatal events. This study investigated trends of these perinatal health indicators in Germany. Perinatal data on 10,696,831 in-hospital live births from 2008 to 2022 were obtained from quality assurance institutes. Joinpoint regression analysis was used to quantify trends of low Apgar score and UA pH. Additional analyses stratified by mode of delivery were performed on term singletons with cephalic presentation. Robustness against unmeasured confounding was analyzed using the E-value sensitivity analysis. The overall rates of 5-min Apgar scores < 7 and UA pH < 7.10 in liveborn infants were 1.17% and 1.98%, respectively. For low Apgar scores, joinpoint analysis revealed an increase from 2008 to 2011 (annual percent change (APC) 5.19; 95% CI 3.66-9.00) followed by a slower increase from 2011 to 2019 (APC 2.56; 95% CI 2.00-3.03) and a stabilization from 2019 onwards (APC - 0.64; 95% CI - 3.60 to 0.62). The rate of UA blood pH < 7.10 increased significantly between 2011 and 2017 (APC 5.90; 95% CI 5.15-7.42). For term singletons in cephalic presentation, the risk amplification of low Apgar scores was highest after instrumental delivery (risk ratio 1.623, 95% CI 1.509-1.745), whereas those born spontaneous had the highest increase in pH < 7.10 (risk ratio 1.648, 95% CI 1.615-1.682).          Conclusion: Rates of low 5-min Apgar scores and UA pH in liveborn infants increased from 2008 to 2022 in Germany. What is Known: • Low Apgar scores at 5 min after birth and umbilical arterial blood pH are associated with adverse perinatal outcomes. • Prospective collection of Apgar scores and arterial blood pH data allows for nationwide quality assurance. What is New: • The rates of liveborn infants with 5-min Apgar scores < 7 rose from 0.97 to 1.30% and that of umbilical arterial blood pH < 7.10 from 1.55 to 2.30% between 2008-2010 and 2020-2022. • In spontaneously born term singletons in cephalic presentation, the rate of metabolic acidosis with pH < 7.10 and BE < -5 mmol/L in umbilical arterial blood roughly doubled between the periods 2008-2010 and 2020-2022.

Public Attitudes Toward Ethics and Practices in End-of-Life Decision-Making for Neonates.

Importance: Attitudes toward end-of-life decision-making in neonatology have been studied in physicians and other health care professionals and are mostly shaped by their clinical education and work experiences. In contrast, attitudes among the general public have not yet been investigated. Objective: To assess (1) attitudes in the general public toward euthanasia and withdrawal of life-prolonging treatment in neonates with severe life-limiting conditions, (2) knowledge of current German recommendations, and (3) values in the German society regarding ethical issues and proxy decisions at the beginning of life. Design, Setting, and Participants: This cross-sectional study was performed in Germany and used an exploratory design to analyze responses to an interview conducted by an independent, established commissioned polling institute in March and April 2022. Participants were 16 years or older, with German language fluency and comprehension and living in Germany. Main Outcomes and Measures: Knowledge about recommendations for euthanasia and withdrawal of life-prolonging treatment as well as personal attitudes toward (1) euthanasia and withdrawal of life-prolonging treatment and (2) surrogate end-of-life decision-making for newborn infants were assessed. Results: The study included 2116 participants (1077 females [50.9%]; mean [SD] age 52.1 [18.7] years). Of the participants, 16.8% (311 of 1851) reported knowing the German recommendations for euthanasia and withdrawal of life-prolonging treatment for neonates. Euthanasia and withdrawal of life-prolonging treatment were supported by 64.7% (1369 of 2116) and 77.9% (1649 of 2116) of respondents, respectively. Shared decision-making between parents and physicians for neonates in end-of-life situations was supported by 65.6% of participants (1388). In situations where shared decision-making was not possible, 73.4% of respondents (1019 of 1388) put the ultimate decision to the parents. The magnitude of the associations was low between sociodemographic factors and views on ethical issues and customary practices involved in end-of-life decisions for neonates. Conclusions and Relevance: Results of this cross-sectional study suggested that most respondents were not aware of the national German recommendations for euthanasia and withdrawal of life-prolonging treatment for sick and extremely preterm newborns. When counseling parents of periviable newborns, clinicians may need to exert more effort in explaining the legal and ethical framework; a highly individualized approach is warranted.

Pancreatic Insufficiency, Digestive Enzyme Supplementation, and Postnatal Growth in Preterm Babies.

BACKGROUND: Optimising postnatal growth facilitates better long-term neonatal neurodevelopmental outcomes. Early postnatal growth is often hindered by a variety of factors unique to the extrauterine environment and digestive immaturity both contributing to reduced enteral feed tolerance during the first few days and weeks after birth. Preterm infants display varying levels of pancreatic insufficiency that are related to gestational age and providing digestive enzyme supplementation, may be one way in which to improve postnatal growth in enterally fed preterm babies. SUMMARY: In this review, we explore which exocrine pancreatic enzymes are deficient in preterm babies, the methods by which exocrine pancreatic function is measured, potential avenues by which digestive enzyme replacement might improve postnatal growth failure, and which babies might benefit most from this intervention. KEY MESSAGES: Pancreatic exocrine function exhibits developmental immaturity in extremely preterm infants and may contribute to postnatal growth failure. Stool elastase is a simple, non-invasive method of assessing pancreatic function in preterm infants. Available evidence does not currently support routine use of digestive enzyme supplementation in preterm infants.

Retinal blood flow velocities in infants with retinopathy of prematurity after intravitreal administration of bevacizumab.

BACKGROUND/OBJECTIVES: Progression of retinopathy of prematurity (ROP) is associated with increased retinal blood flow velocities. We investigated changes of central retinal arterial and venous blood flow after intravitreal administration of bevacizumab. SUBJECTS/METHODS: Prospective observational study using serial ultrasound Doppler imaging in preterm infants with bevacizumab-treated ROP. Eyes were examined 1 [0-2] days before injection (median [interquartile range]), and at three time points after injection (1 [1-2] days, 6 [3-8] days, and 17 [9-28] days). Preterm infants with ROP stage 2 displaying spontaneous regression served as controls. RESULTS: In 21 eyes of 12 infants with bevacizumab-treated ROP, peak arterial systolic velocity declined from 13.6 [11.0-16.3] cm/s prior to intravitreal bevacizumab to 11.2 [9.4-13.9] cm/s, 10.6 [9.2-13.3] cm/s and 9.3 [8.2-11.0] cm/s at discharge (p = .002). There was also a decline of the arterial velocity time integral (from 3.1 [2.3-3.9] cm to 2.9 [2.4-3.5], 2.7 [2.3-3.2] cm and 2.2 [2.0-2.7], p = .021) and mean velocity in the central retinal vein (from 4.5 [3.6-5.8] cm/s to 3.7 [2.6-4.1] cm/s, 3.5 [3.0-4.3] cm/s, and 3.2 [2.8-4.6] cm/s, p = .012). Arterial end-diastolic velocity and resistance index remained unchanged. Blood flow velocities in bevacizumab-treated eyes examined before injection were significantly higher than those measured in untreated eyes that ultimately showed spontaneous regression of ROP. Sequential examinations in these controls did not reveal any declines of retinal blood flow velocities. CONCLUSION: Increased retinal arterial and venous blood flow velocities in infants with threshold ROP decline following intravitreal bevacizumab injection.

No change in mother's own milk provision and breastfeeding rates in preterm infants during the COVID-19 pandemic.

AIM: The aim of the study was to evaluate the duration of mother's own milk (MOM) provision to preterm very low-birth weight (VLBW, <1500 g) infants during the COVID-19 pandemic. We hypothesised that COVID-19 restrictions would reduce the duration of MOM provision. METHODS: This retrospective study compared VLBW infants born at the Berlin university hospital during the pandemic (15 March 2020 to 14 March 2021, n = 108) with infants born in the pre-pandemic year (01 January 2019 to 31 January 2019, n = 121). We calculated the duration of MOM provision and analysed factors associated with its early cessation. RESULTS: During the pandemic, the rate of primiparous mothers increased from 29% to 44% while the distribution of all other parental and infants' characteristics remained similar. There were no differences in the median duration of MOM provision (47 vs. 51 days), feeding type (MOM 67% vs. 65%) and breastfeeding rates at discharge (exclusive, 8% vs. 13%; partial 69% vs. 60%). Cox proportional hazard analysis revealed smoking during pregnancy and parental school education consistently as independent risk factors for early cessation of MOM provision. CONCLUSION: Supply of MOM for VLBW infants can be upheld also during pandemic restrictions.

Similar adverse outcome rates with high or low oxygen saturation targets in an area with low background mortality.

Background: Randomized controlled trials have indicated reduced mortality rates in very preterm infants assigned to high compared to low oxygen saturation (SpO2) target levels, accompanied by higher rates of retinopathy of prematurity and bronchopulmonary dysplasia. However, the benefit-to-harm ratio may depend on the local background mortality risk. We therefore aimed to quantify the risk-benefit ratios of different SpO2 target ranges in 10 tertiary newborn intensive care units (NICUs) in East Germany. Methods: In a retrospective multicenter study, 1,399 infants born between 2008 and 2012 at a gestational age between 24 0/7 and 27 6/7 weeks and with a birthweight below 1,250 g were grouped according to the hospital's target SpO2 range [high oxygen saturation group (HOSG) above 90%], low oxygen saturation group (LOSG) below 90%] and the compliance of units with their target SpO2 range. The association between neonatal morbidities, neurodevelopmental outcomes, selected treatment strategies, and target SpO2 ranges was calculated using chi-squared and Mann Whitney U tests. Results: Nine of the ten participating NICUs met their SpO2 target ranges. Five units were considered as HOSG, and five units were considered as LOSG. Necrotizing enterocolitis and intraventricular hemorrhage grade ≥ 2 occurred significantly more frequently in the HOSG than in the LOSG (8.4% vs. 5.1%, p = 0.02; and 26.6% vs. 17.7%, p < 0.001). No significant differences in the mortality rate and the rate of retinopathy of prematurity were found. Conclusion: In our patient population, a lower SpO2 target range was not associated with increased safety risks in extremely preterm infants. We cannot be sure that our outcome differences are associated with differences in oxygen saturations due to the retrospective study design and the differences in site practices.

Effect of Early Erythropoietin on Retinopathy of Prematurity: A Stratified Meta-Analysis.

BACKGROUND: Recombinant human erythropoietin (rhEPO) lost its role in minimizing red blood cell transfusion in very preterm infants after it had been associated with severe retinopathy of prematurity (ROP). Previous systematic reviews did not stratify ROP by gestation and birth weight (BW). OBJECTIVES: The aim of this study was to investigate the effect of early prophylactic rhEPO on ROP in a stratified meta-analysis of randomized controlled trials (RCTs). METHODS: The databases EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials were searched in January 2022 and complemented by citation searching. RCTs comparing early rhEPO treatment with no treatment or placebo were selected if they were published in a peer-reviewed journal and reported ROP outcomes. Previously unpublished data were requested from the study authors to allow stratified analyses by gestational age (GA) and BW. Data were extracted and analyzed using the standard methods of the Cochrane Neonatal Review Group. Pre-specified outcomes were "ROP stage ≥3" (primary outcome) and "any ROP." RESULTS: Fourteen RCTs, comprising 2,040 infants of <29 weeks of GA, were included for meta-analysis. Data syntheses showed no effects of rhEPO on ROP stage ≥3 or on any ROP, neither in infants of <29 weeks GA, nor in infants of <1,000 g BW, nor in any GA strata. The risk ratio (95% confidence interval) for ROP stage ≥3 in infants of <29 weeks of GA was 1.13 (0.84, 1.53), p = 0.41 (quality of evidence: moderate). CONCLUSIONS: The present meta-analysis detected no effects of early rhEPO on ROP in any comparison, but most stratified analyses were limited by low statistical power.

Cardioprotective Effects of Dexmedetomidine in an Oxidative-Stress In Vitro Model of Neonatal Rat Cardiomyocytes.

Preterm birth is a risk factor for cardiometabolic disease. The preterm heart before terminal differentiation is in a phase that is crucial for the number and structure of cardiomyocytes in further development, with adverse effects of hypoxic and hyperoxic events. Pharmacological intervention could attenuate the negative effects of oxygen. Dexmedetomidine (DEX) is an α2-adrenoceptor agonist and has been mentioned in connection with cardio-protective benefits. In this study, H9c2 myocytes and primary fetal rat cardiomyocytes (NRCM) were cultured for 24 h under hypoxic condition (5% O2), corresponding to fetal physioxia (pO2 32-45 mmHg), ambient oxygen (21% O2, pO2 ~150 mmHg), or hyperoxic conditions (80% O2, pO2 ~300 mmHg). Subsequently, the effects of DEX preconditioning (0.1 µM, 1 µM, 10 µM) were analyzed. Modulated oxygen tension reduced both proliferating cardiomyocytes and transcripts (CycD2). High-oxygen tension induced hypertrophy in H9c2 cells. Cell-death-associated transcripts for caspase-dependent apoptosis (Casp3/8) increased, whereas caspase-independent transcripts (AIF) increased in H9c2 cells and decreased in NRCMs. Autophagy-related mediators (Atg5/12) were induced in H9c2 under both oxygen conditions, whereas they were downregulated in NRCMs. DEX preconditioning protected H9c2 and NRCMs from oxidative stress through inhibition of transcription of the oxidative stress marker GCLC, and inhibited the transcription of both the redox-sensitive transcription factors Nrf2 under hyperoxia and Hif1α under hypoxia. In addition, DEX normalized the gene expression of Hippo-pathway mediators (YAP1, Tead1, Lats2, Cul7) that exhibited abnormalities due to differential oxygen tensions compared with normoxia, suggesting that DEX modulates the activation of the Hippo pathway. This, in the context of the protective impact of redox-sensitive factors, may provide a possible rationale for the cardio-protective effects of DEX in oxygen-modulated requirements on survival-promoting transcripts of immortalized and fetal cardiomyocytes.

Dexmedetomidine Protects Cerebellar Neurons against Hyperoxia-Induced Oxidative Stress and Apoptosis in the Juvenile Rat.

The risk of oxidative stress is unavoidable in preterm infants and increases the risk of neonatal morbidities. Premature infants often require sedation and analgesia, and the commonly used opioids and benzodiazepines are associated with adverse effects. Impairment of cerebellar functions during cognitive development could be a crucial factor in neurodevelopmental disorders of prematurity. Recent studies have focused on dexmedetomidine (DEX), which has been associated with potential neuroprotective properties and is used as an off-label application in neonatal units. Wistar rats (P6) were exposed to 80% hyperoxia for 24 h and received as pretreatment a single dose of DEX (5µg/kg, i.p.). Analyses in the immature rat cerebellum immediately after hyperoxia (P7) and after recovery to room air (P9, P11, and P14) included examinations for cell death and inflammatory and oxidative responses. Acute exposure to high oxygen concentrations caused a significant oxidative stress response, with a return to normal levels by P14. A marked reduction of hyperoxia-mediated damage was demonstrated after DEX pretreatment. DEX produced a much earlier recovery than in controls, confirming a neuroprotective effect of DEX on alterations elicited by oxygen stress on the developing cerebellum.

Protective Effect of Dexmedetomidine against Hyperoxia-Damaged Cerebellar Neurodevelopment in the Juvenile Rat.

Impaired cerebellar development of premature infants and the associated impairment of cerebellar functions in cognitive development could be crucial factors for neurodevelopmental disorders. Anesthetic- and hyperoxia-induced neurotoxicity of the immature brain can lead to learning and behavioral disorders. Dexmedetomidine (DEX), which is associated with neuroprotective properties, is increasingly being studied for off-label use in the NICU. For this purpose, six-day-old Wistar rats (P6) were exposed to hyperoxia (80% O2) or normoxia (21% O2) for 24 h after DEX (5 µg/kg, i.p.) or vehicle (0.9% NaCl) application. An initial detection in the immature rat cerebellum was performed after the termination of hyperoxia at P7 and then after recovery in room air at P9, P11, and P14. Hyperoxia reduced the proportion of Calb1+-Purkinje cells and affected the dendrite length at P7 and/or P9/P11. Proliferating Pax6+-granule progenitors remained reduced after hyperoxia and until P14. The expression of neurotrophins and neuronal transcription factors/markers of proliferation, migration, and survival were also reduced by oxidative stress in different manners. DEX demonstrated protective effects on hyperoxia-injured Purkinje cells, and DEX without hyperoxia modulated neuronal transcription in the short term without any effects at the cellular level. DEX protects hyperoxia-damaged Purkinje cells and appears to differentially affect cerebellar granular cell neurogenesis following oxidative stress.