Association of antenatal corticosteroids and the mode of delivery with the mortality and morbidity of infants weighing less than 1,500g at birth in Japan

Risk Factors for Mortality or Major Morbidities of Very Preterm Infants: A Study from Thailand

OBJECTIVE

 Very preterm neonates have high rates of composite outcomes featuring mortality and major morbidities. If the modifiable risk factors could be identified, perhaps the rates could be decreased especially in resource-limited settings.

STUDY DESIGN

 We performed a prospective study in a Thai neonatal intensive care unit to identify the risk factors of composite outcomes between 2014 and 2021. The inclusion criterion was neonates who were born in our hospital at a gestational age (GA) of less than 32 weeks. The exclusion criteria were neonates who died in the delivery room or had major congenital anomalies. The composite outcomes were analyzed by multivariable logistic regression with adjusted odds ratios (aORs) and a 95% confidence interval (CI).

RESULTS

 Over the 8-year study period, 555 very preterm inborn neonates without major birth defects were delivered. The composite outcomes were 29.4% (163/555). The medians (interquartile ranges) of GA and birth weights of the neonates were 29 (27-31) weeks and 1,180 (860-1,475) grams, respectively. By multivariable analysis, GA (aOR: 0.65; 95% CI: 0.55-0.77), small for GA (aOR: 4.93; 95% CI: 1.79-13.58), multifetal gestation (aOR: 2.23; 95% CI: 1.12-4.46), intubation within 24 hours (aOR: 5.39; 95% CI: 1.35-21.64), and severe respiratory distress syndrome (aOR: 5.00; 95% CI: 1.05-23.89) were significantly associated with composite outcomes.

CONCLUSION

 Very preterm infants who had a lower GA were small for GA, twins or more, respiratory failure on the first day of life, and severe respiratory distress syndrome were associated with mortality and/or major morbidities.

KEY POINTS

· In very preterm neonates, the composite outcomes and mortality rate were 29.4 and 12.3%.. · Composite outcomes were associated with lower GA, SGA, multifetal gestation, intubation, and severe RDS.. · Mortality was associated with lower GA or Apgar score at 5minutes, SGA, and PPHN..

Relationship between the mode of delivery, morbidity and mortality in preterm infants

BACKGROUND

The aim of the study, to evaluate the relationship between mode of delivery and preterm morbidities and mortality, who born ≤34 weeks of gestation within 1 year.

MATERIALS AND METHODS

Babies were divided into two groups as who were born by cesarean section (CS) and vaginal delivery (VD) between March 2019 and March 2020. Infants born at ≤28 weeks were also analyzed.

RESULTS

The rate of CS delivery was 76% (378) in the whole group and 73% (115) in the babies of ≤28 gestational weeks. The most common maternal factor causing CS was preeclampsia (25%). The antenatal corticosteroid (ACS) application rate was 30% (152) in the whole group and 30% (45) in infants of ≤28 weeks. Rate of babies with an Apgar score of <5 at 5th min, asphyxia, multiple organ failure, development of severe respiratory distress syndrome, severe intraventricular hemorrhage (IVH) and mortality were significantly increased in infants born VD (for all p < 0.05). Mortality was significantly higher when gestational age was ≤28 weeks, birth weight was ≤1500 g and ACS was not administered (p < 0.001 for all).

CONCLUSION

Mortality, severe IVH, neonatal asphyxia and multiple organ failure were found to be higher in those who were born by VD. These findings suggest that these results were due to inadequate prenatal care and follow-up and lack of ACS.

Influence of Anaemia on Multifactorial Disease Retinopathy of Prematurity: A Prospective Observational Study

Background: Retinopathy of prematurity (ROP), a preventable cause of childhood blindness, is a severe complication of preterm (PT) birth treatment.

Purpose: The purpose of this study is to analyse the risk factors (RF) associated with the development and progression of ROP. Particular focus is on the contribution of anaemia towards the development and progression of ROP.

Methods: This study is a prospective observational study done in the Department of Paediatrics at Meenakshi Mission Hospital & Research Centre, Madurai, over 12 months from May 2013 to April 2014. The study included all consecutively admitted neonates born in and out of the hospital with gestational age (GA) less than or equal to 35 weeks or birth weight (BW) less than or equal to 2 kg and assessed for the gestational, perinatal, and postnatal RF. In addition, at the time of ROP screening, haemoglobin (Hb) and haematocrit (Hct) were checked. The statistical analysis was performed by Stata 11.1 (StataCorp LLC, College Station, TX).

Result: The incidence of ROP in our study (46.7%) is higher than previously reported in India. In our study, GA and weight of the neonate at birth have a significant association with ROP incidence. Anaemia in our study is significantly associated with ROP incidence but not as an independent RF. The outcome of various stages of ROP is statistically significant, showing early stages 1 and 2 have more chances of spontaneous regression, and stages 3 and 4 are more likely to need treatment. Two cases in our study with stage 4 ROP had no complications, and none had stage 5 disease.

Conclusion: Anaemia should be avoided or corrected in PT newborns as it is a potential and avoidable RF for ROP development. The limitation of our study is the small sample size, and probably more extensive randomized trials will help make this association clear. We recommend ROP screening for PT babies with GA less than 35 weeks and BW less than 2 kg who have the RF amounting to screening and done as per protocol.

Delivery Mode and Neurological Complications in Very Low Birth Weight Infants

OBJECTIVE

 The risk of intraventricular hemorrhage (IVH) and periventricular leukomalacia is associated with low birth weight and gestational age. Caesarean section (CS) may reduce the risk of IVH, although it has been a matter of debate. The aim of this study was to evaluate the influence of the mode of delivery (MOD) on the development of IVH and cystic periventricular leukomalacia (cPVL).

STUDY DESIGN

 We analyzed an initial cohort of 11,023 very low birth weight (VLBW) infants born between January 2010 and December 2019. Infants with major malformations and gestational age <23 weeks and ≥32 weeks were excluded. A final cohort of 8,251 newborns was analyzed. Data was collected from Portuguese National very low birth weight registry. Cases were classified as vaginal delivery (VD) or CS. Outcome was assessed in univariate and logistic regression analyses.

RESULTS

 The median gestational age was 29 weeks (IQR 3.3) and the median weight was 1,100 g (IQR 555). The prevalence of IVH was significantly higher in the VD group versus the CS group, across all grading levels:1,144 newborns had grade I IVH (16% VD vs. 14% CS, p <0.01), 706 had grade II IVH (12% VD vs. 7.6% CS, p <0.01), and 777 had grade III IVH (14% VD vs. 7.9% CS, p <0.01). Post-hemorrhagic ventricular dilatation occurred in 457 newborns (8.3% VD vs. 4.6% CS, p <0.01) and 456 newborns had periventricular hemorrhagic infarction (8.4% VD vs. 4.5% CS, p <0.01). There was no association between MOD and cPVL. After applying a logistic regression analysis, including known risk factors for IVH and cPVL, VD was independently associated with an increased risk of IVH (odds ratio [OR] 1.600[1.423-1.799], p <0.001) and its complications (OR 1.440[1.195-1.735], p <0.001). MOD was not associated with an increased risk of cPVL.

CONCLUSION

 Our study suggests that CS is associated with a reduced risk of IVH and its complications in preterm VLBW infants < 32 weeks of gestational age. A CS should be considered in this group of infants to prevent the development of IVH and its complications.

KEY POINTS

· IVH and cPVL are risk factors for neurological disabilities.. · CS may decrease the risk of IVH in preterms <32 weeks GA.. · There is no association between the MOD and cPVL..

Risk Factors for Periventricular Leukomalacia in Preterm Infants: A Systematic Review, Meta-analysis, and GRADE-Based Assessment of Certainty of Evidence

BACKGROUND

We analyzed the certainty of evidence (CoE) for risk factors of periventricular leukomalacia (PVL) in preterm neonates, a common morbidity of prematurity.

METHODS

Medline, CENTRAL, Embase, and CINAHL were searched. Cohort and case-control studies and randomised randomized controlled trials were included. Data extraction was performed in duplicate. A random random-effects meta-analysis was utilizedused. CoE was evaluated as per Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines.

RESULTS

One hundred eighty-six studies evaluating 95 risk factors for PVL were included. Of the 2,509,507 neonates assessed, 16,569 were diagnosed with PVL. Intraventricular hemorrhage [adjusted odds ratio: 3.22 (2.52-4.12)] had moderate CoE for its association with PVL. Other factors such as hypocarbia, chorioamnionitis, PPROM >48 hour, multifetal pregnancy reduction, antenatal indomethacin, lack of antenatal steroids, perinatal asphyxia, ventilation, shock/hypotension, patent ductus arteriosus requiring surgical ligation, late-onset circulatory collapse, sepsis, necrotizing enterocolitis, and neonatal surgery showed significant association with PVL after adjustment for confounders (CoE: very low to low). Amongst the risk factors associated with mother placental fetal (MPF) triad, there was paucity of literature related to genetic predisposition and defective placentation. Sensitivity analysis revealed that the strength of association between invasive ventilation and PVL decreased over time (P < 0.01), suggesting progress in ventilation strategies. Limited studies had evaluated diffuse PVL.

CONCLUSION

Despite decades of research, our findings indicate that the CoE is low to very low for most of the commonly attributed risk factors of PVL. Future studies should evaluate genetic predisposition and defective placentation in the MPF triad contributing to PVL. Studies evaluating exclusively diffuse PVL are warranted.

Retinopathy of prematurity in Saudi Arabia: Exploring maternal risk factors

PURPOSE:

Retinopathy of prematurity (ROP) is a preventable blinding disorder affecting preterm infants. To date, maternal risk factors have not been studied in Saudi Arabia. This study aims to identify possible maternal risk factors for any stage and type 1 ROP.

MATERIALS AND METHODS:

A total of 295 preterm infants screened for ROP between November 2013 and December 2018 at a Saudi Arabian tertiary-care hospital were included. We included infants with a gestational age ≤ 32 weeks and/or birth weight (BW) ≤1500 g. We analyzed 28 maternal and neonatal risk factors.

RESULTS:

The incidence of ROP at any stage and Type 1 were 31.9% and 7%, respectively. In the univariate analysis, the only maternal factor associated with any stage of ROP was spontaneous vaginal delivery (P = 0.049), but no maternal factor was an independent risk factor for type 1 ROP. Multivariate logistic regression analysis identified lower BW, lower gestational age and longer neonatal intensive care unit stay as independent risk factors for the development of ROP at any stage (P < 0.05). For Type 1 ROP, lower BW, and intraventricular hemorrhage were significant independent risk factors (P < 0.05).

CONCLUSION:

The only maternal risk factor related to ROP was spontaneous vaginal delivery, which increased the risk of any stage of ROP. The single most predictive risk factor for any stage of ROP and Type 1 ROP was low BW. These findings emphasize the role of the obstetrician in promoting health care and modifying maternal risk factors to prevent preterm births related to a low BW.

Antenatal corticosteroid therapy is associated with a lower risk of cystic periventricular leukomalacia

AIM

To evaluate the association of antenatal corticosteroids (ACS) therapy on the risk for cystic periventricular leukomalacia (c-PVL) in very low birth weight (VLBW), very preterm infants, whilst accounting for the occurrence of major neonatal morbidities; sepsis, necrotising enterocolitis, intraventricular haemorrhage and bronchopulmonary dysplasia.

METHODS

Population-based observational cohort study applying data collected by the Israel national VLBW infant database from 1995-2016.

RESULTS

Cystic PVL was diagnosed in 692 (6.8%) of the 10,170 study infants. Among 7522 infants exposed to ACS, the rate of c-PVL was 5.4%, compared to 10.7% among those not exposed (p < 0.0001). ACS was associated with significantly lower odds for c-PVL (Odds Ratio [OR] 0.69, 95% confidence interval [CI] 0.57-0.84). In subgroup analyses, excluding infants with one or more morbidities the rates of c-PVL ranged from 2.7% to 5.4% among infants exposed to ACS compared to 5.6% to 10.7% in those not exposed (all p < 0.0001). ACS was associated with significantly lower OR's for c-PVL in all subgroups, ranging from 0.52 (95% CI 0.40-0.66) to 0.62 (95% CI 0.50-0.77).

CONCLUSION

Infants exposed to ACS had a significantly lower risk of c-PVL. Subgroup analyses excluding infants with major neonatal comorbidities showed a consistent reduction of 40%-50% in the risk for c-PVL following ACS therapy.

Evidence for the Management of Bronchopulmonary Dysplasia in Very Preterm Infants

Background: Very preterm birth often results in the development of bronchopulmonary dysplasia (BPD) with an inverse correlation of gestational age and birthweight. This very preterm population is especially exposed to interventions, which affect the development of BPD. Objective: The goal of our review is to summarize the evidence on these daily procedures and provide evidence-based recommendations for the management of BPD. Methods: We conducted a systematic literature research using MEDLINE/PubMed on antenatal corticosteroids, surfactant-replacement therapy, caffeine, ventilation strategies, postnatal corticosteroids, inhaled nitric oxide, inhaled bronchodilators, macrolides, patent ductus arteriosus, fluid management, vitamin A, treatment of pulmonary hypertension and stem cell therapy. Results: Evidence provided by meta-analyses, systematic reviews, randomized controlled trials (RCTs) and large observational studies are summarized as a narrative review. Discussion: There is strong evidence for the use of antenatal corticosteroids, surfactant-replacement therapy, especially in combination with noninvasive ventilation strategies, caffeine and lung-protective ventilation strategies. A more differentiated approach has to be applied to corticosteroid treatment, the management of patent ductus arteriosus (PDA), fluid-intake and vitamin A supplementation, as well as the treatment of BPD-associated pulmonary hypertension. There is no evidence for the routine use of inhaled bronchodilators and prophylactic inhaled nitric oxide. Stem cell therapy is promising, but should be used in RCTs only.

The development of the hypothalamus-pituitary-adrenal axis during infancy may be affected by antenatal glucocorticoid therapy

BACKGROUND

Developmental changes in the hypothalamus-pituitary-adrenal (HPA) axis during infancy have been reported in term infants, but those in preterm infants have yet to be elucidated. If developmental changes in the HPA axis of preterm infants are modulated by any factors, it may affect their future health. Few studies have examined the lasting consequences of antenatal glucocorticoids on the development of the HPA axis.

METHODS

We measured pre- and post-palivizumab vaccination salivary cortisol values in two conforming periods of three-months intervals during infancy, and compared cortisol values and the response of cortisol secretion between groups with and without antenatal glucocorticoid (AG) therapy.

RESULTS

Although the strength of the response of cortisol secretion to palivizumab fell age-dependently (until late infancy) in the Non-AG group, the opposite pattern was exhibited in the AG group. The changes of the delta cortisol values between the 2 groups were significant.

CONCLUSIONS

This study suggests that the HPA axis of preterm infants whose mothers receive AG therapy may be upregulated during infancy, possibly leading to long lasting health problems.

Primary prevention of ROP and the oxygen saturation targeting trials

Reducing the burden of visual morbidity from retinopathy of prematurity (ROP) begins with primary prevention, and improvements in neonatal care with a positive impact on ROP are possible in all settings. Strategies range from rigorous adoption of inexpensive evidence-based protocols, for example on temperature control, prevention of sepsis and support for breast-milk feeding, through to comprehensive quality improvement programmes, and fostering team work and camaraderie. Oxygen monitoring is essential for very preterm infants receiving supplementary oxygen. The Neonatal Oxygenation Prospective Meta-analysis (NeOProM) collaboration has reported analysis of five trials of oxygen saturation (SpO₂) targeting in very preterm infants and shown that a SpO₂ target of 85-89% compared to 91-95% was associated with increased mortality (on average 28 extra deaths for every 1000 infants treated). Adopting a SpO₂ target higher than 85-89% might increase the risk of ROP for some infants, highlighting the importance of pursuing all other means of prevention.

[Neonatal morbidity and mortality associated with low adherence to prenatal corticosteroids]

INTRODUCTION

Prenatal corticosteroids reduce neonatal mortality and morbidity; however, there are few studies in developing countries, and with inconsistent results. The purpose of this study was to quantify the frequency of the use of prenatal corticosteroids and to estimate its effect on the morbidity and mortality of premature newborns.

METHODS

A retrospective cohort study was performed on premature newborns selected from a census conducted between January 2016 and August 2017. The use of corticosteroids was taken from the maternal records, and the dependent variables from the neonatal records. An analysis was made of the relationship using logistic regression, adjusted to gestational age and weight.

RESULTS

The study included 1083 premature infants of which 53.3% were male. The mean gestational age was 33.4 weeks. Corticosteroids were received by 42%, with latency ≥24hours in 23.6% and ≥48hours in 13.8%. Respiratory distress syndrome was observed in 35% (379/1083), early neonatal sepsis in 4.4% (48/1083), late neonatal sepsis in 10.7% (116/1083), intraventricular haemorrhage in 15.1% (137/908), chronic lung disease in 51.4% (165/321), and death in 22.3% (242/1083). Prenatal corticosteroids decreased the risk of death in children under 34 weeks (OR 0.63, 95% CI 0.40-0.98). The decrease was greater if they presented with latency ≥48hours (OR 0.40, 95% CI 0.20-0.80). The rest of the dependent variables were not modified by the intervention.

CONCLUSIONS

In preterm infants, 42% received antenatal corticosteroids. In those with less than 34 weeks, there was a decrease in the risk of death without changes in morbidity.

Retinopathy of prematurity: a review of risk factors and their clinical significance

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

Late-onset circulatory collapse of prematurity

Late-onset circulatory collapse (LCC) is a refractory hypotension occurring after the early neonatal period (>day 7), in very low-birthweight infants. Typically, infants stabilized within the early neonatal period develop sudden onset of circulatory collapse after the early neonatal period. The underlying pathophysiology of LCC is considered to be relative adrenal insufficiency, which is well known in Japan, but is not widely accepted in North America or Europe. The current increase in LCC in Japan suggests that the principal trigger is related to recent trends in neonatal medicine and/or newly introduced treatments for preterm infants, but the pathophysiology has not been fully elucidated. In this review, based on current knowledge regarding LCC, the pathophysiology is discussed.

International variations and trends in the treatment for retinopathy of prematurity

OBJECTIVE

To compare the rates of retinopathy of prematurity (ROP) and treatment of ROP by laser or intravitreal anti-vascular endothelial growth factor among preterm neonates from high-income countries participating in the International Network for Evaluating Outcomes (iNeo) of neonates.

METHODS

A retrospective cohort study was conducted on extremely preterm infants weighing <1500 g at 24⁰ to 27⁶ weeks' gestation who were admitted to neonatal units in Australia/New Zealand, Canada, Finland, Israel, Japan, Spain, Sweden, Switzerland, Tuscany (Italy) and the UK between 2007 and 2013. Pairwise comparisons of ROP treatment in survivors between countries were evaluated by Poisson and multivariable logistic regression analyses after adjustment for confounders. A composite outcome of death or ROP treatment was compared between countries using logistic regression and standardised ratios.

RESULTS

Of 48 087 infants included in the analysis, 81.8% survived to 32 weeks postmenstrual age, and 95% of survivors were screened for ROP. Rates of any ROP ranged from 25.2% to 91.0% in Switzerland and Japan, respectively, among those examined. The overall rate of those receiving treatment was 24.9%, which varied from 4.3% to 30.4%. Adjusted risk ratios for ROP treatment were lower for Switzerland in all pairwise comparisons, whereas Japan displayed significantly higher ratios. Comparisons of the composite outcome between countries revealed similar, but less marked differences.

CONCLUSIONS

Rates of any ROP and ROP treatment varied significantly between iNeo members, while an overall decline in ROP treatment was observed during the study period. It is unclear whether these variations represent differences in care practices, diagnosis and/or treatment thresholds.

Infantile Respiratory Distress Syndrome and Its Probable Links With Parameters of the Maternal Patient History: A Forensic Case Report

Respiratory distress syndrome (RDS) has a major contribution to neonatal mortality worldwide. Multiple factors associated with increased risk for RDS have been documented to effectively understand the emergence and progression of this disorder. A portion of these parameters has been broadly examined whereas the role of others, despite being clinically described, has not been fully evaluated. In this report, we analyze a forensic RDS case of a late preterm infant. Taking the maternal medical history into account, we focused on 2 not widely established risk factors, oligohydramnios and maternal age, discussing their possible pathophysiological relation to the development of RDS. Simultaneously, the fundamental role of the histopathological examination as a diagnostic tool resurfaces. Following a multidisciplinary approach derived from the collaboration of clinicians and researchers, the identification of factors that precipitate or contribute to this syndrome can be enhanced, leading to novel prognostic and therapeutic strategies against RDS.