Trends in epidemiology and outcomes of respiratory distress syndrome in the United States

Non-invasive Respiratory Support or Intubation during Stabilization after Birth and Neonatal and Neurodevelopmental Outcomes in Infants Born Preterm at 23-25 Weeks of Gestation

OBJECTIVE

To examine the association between non-invasive respiratory support (NRS) or tracheal intubation (TI) during stabilization in infants born at 23-25 weeks of gestation and severe brain injury (sBI) or death, and significant neurodevelopmental impairment (sNDI).

STUDY DESIGN

A retrospective cohort study of infants born at 230/7-256/7 weeks of gestation in Canada. We compared infants successfully managed with NRS or TI during 30 minutes after birth. The primary outcomes were sBI or death before discharge, and sNDI among survivors with follow-up data at 18-24 months corrected age. The associations between exposures and outcomes were assessed using logistic regression models, and propensity score matched (PSM) analyses.

RESULTS

The mean (SD) of gestational age and birth weight were 24.6 (0.6), 24.3 (0.7) weeks [p <0.01], and 757 (173), 705 (130) grams [p <0.01] in the NRS, and TI groups, respectively, and 77% of infants in the NRS group were intubated by 7 days of age. sBI or death occurred in 25% (283/1118), and 36% (722/ 2012) of infants in the NRS and TI groups, respectively (adjusted odds ratio [aOR] and 95% confidence interval [CI] 0.74 [0.60, 0.91]). Among survivors with follow-up data, sNDI occurred in 17% (96/551), and 23% (218/937) of infants in the NRS and TI groups, respectively (aOR [95% CI] 0.77 [0.60, 0.99]). In the PSM analyses (NRS vs TI), results were consistent for sBI or death (OR [95% CI] 0.72 [0.60, 0.86]), but not for sNDI (OR [95% CI] 0.78 [0.58, 1.05]).

CONCLUSIONS

Infants born at 23-25 weeks who were successfully managed with NRS, compared with TI, in the first 30 minutes after birth had lower odds of sBI or death before discharge, but had no significant differences in neurodevelopmental outcomes among survivors.

Metabolic and Microbial Dysregulation in Preterm Infants with Neonatal Respiratory Distress Syndrome: An Early Developmental Perspective

Neonatal respiratory distress syndrome (NRDS) is one of the most severe respiratory disorders in preterm infants (PTIs) due to immature lung development. To delineate the serum metabolic alterations and gut microbiota variations in NRDS and assess their implications on neonatal development, we enrolled 13 NRDS neonates and 12 PTIs and collected fecal and serum specimens after birth. Longitudinal fecal sampling was conducted weekly for a month in NRDS neonates. NRDS neonates were characterized by notably reduced gestational ages and birth weights and a higher rate of asphyxia at birth relative to PTIs. Early postnatal disturbances in tryptophan metabolism were evident in the NRDS group, concomitant with elevated relative abundance of Haemophilus, Fusicatenibacter, and Vibrio. Integrative multiomics analyses revealed an inverse relationship between tryptophan concentrations and Blautia abundance. At one-week old, NRDS neonates exhibited cortisol regulation anomalies and augmented hepatic catabolism. Sequential microbial profiling revealed distinct gut microbiota evolution in NRDS subjects, characterized by a general reduction in potentially pathogenic bacteria. The acute perinatal stress of NRDS leads to mitochondrial compromise, hormonal imbalance, and delayed gut microbiota evolution. Despite the short duration of NRDS, its impact on neonatal development is significant and requires extended attention.

Establishment and Validation of a Risk Prediction Model for Non-Invasive Ventilation Failure After Birth in Premature Infants with Gestational Age < 32 Weeks

OBJECTIVES

This study was performed to construct and validate a risk prediction model for non-invasive ventilation (NIV) failure after birth in premature infants with gestational age < 32 weeks.

METHODS

The data were derived from the multicenter retrospective study program - Jiangsu Provincial Neonatal Respiratory Failure Collaboration Network from Jan 2019 to Dec 2021. The subjects finally included were preterm infants using NIV after birth with gestational age less than 32 weeks and admission age within 72 h. After screening by inclusion and exclusion criteria, 1436 babies were subsequently recruited in the study, including 1235 infants in the successful NIV group and 201 infants in the failed NIV group.

RESULTS

(1) Gestational age, 5 min Apgar, Max FiO2 during NIV, and FiO2 fluctuation value during NIV were selected by univariate and multivariate analysis. (2) The area under the curve of the prediction model was 0.807 (95% CI: 0.767-0.847) in the training set and 0.825 (95% CI: 0.766-0.883) in the test set. The calibration curve showed good agreement between the predicted probability and the actual observed probability (Mean absolute error = 0.008 for the training set; Mean absolute error = 0.012 for the test set). Decision curve analysis showed good clinical validity of the risk model in the training and test cohorts.

CONCLUSION

This model performed well on dimensions of discrimination, calibration, and clinical validity. This model can serve as a useful tool for neonatologists to predict whether premature infants will experience NIV failure after birth.

Respiratory distress syndrome is associated with increased morbidity and mortality in late preterm births

BACKGROUND

Respiratory distress syndrome is strongly associated with prematurity, including late preterm births. Respiratory distress syndrome has been shown to be associated with certain neonatal morbidities and mortality, but these associations are not well described among late preterm births.

OBJECTIVE

We sought to determine the association between respiratory distress syndrome and adverse neonatal outcomes among late preterm (34-36 weeks) born singleton neonates.

STUDY DESIGN

This is a retrospective cohort study using California's linked vital statistics and patient discharge data (2008-2019). We included singleton, nonanomalous births with a gestational age of 34-36 weeks. Outcomes of interest were interventricular hemorrhage, necrotizing enterocolitis, retinopathy of prematurity, neonatal sepsis, length of hospital stay, neonatal death, and infant death. Chi-square and multivariable Poisson regression analyses were used to examine the association of respiratory distress syndrome with outcomes at each gestational age. Adjusted risk ratio and 95% confidence interval values were estimated.

RESULTS

A total of 242,827 births were included, of which 11,312 (4.7%) had respiratory distress syndrome. We found that among neonates with respiratory distress syndrome, necrotizing enterocolitis was higher at 35 weeks (adjusted risk ratio, 3.97 [95% confidence interval, 1.88-8.41]) and 36 weeks (adjusted risk ratio, 4.53 [95% confidence interval, 1.45-14.13]). Intraventricular hemorrhage, retinopathy of prematurity, neonatal sepsis, and length of hospital stay were significantly higher at 34-36 weeks of gestation in neonates with respiratory distress syndrome. Neonatal death was significantly higher among neonates with respiratory distress syndrome at 35 weeks (adjusted risk ratio, 3.04 [95% confidence interval, 1.58-5.85]) and 36 weeks (adjusted risk ratio, 3.25; 95% confidence interval, 1.59-6.68). In addition, infant death was significantly higher at 35 weeks (adjusted risk ratio, 2.27 [95% confidence interval, 1.43-3.61]) and 36 weeks (adjusted risk ratio, 2.60 [95% confidence interval, 1.58-4.28]).

CONCLUSION

We found that respiratory distress syndrome was associated with intraventricular hemorrhage, retinopathy of prematurity, and sepsis at 34-36 weeks of gestation, whereas respiratory distress syndrome was associated with neonatal death, infant death, and necrotizing enterocolitis at 35 and 36 weeks. Clinicians should keep these outcomes in mind when making decisions about delivery timing, the potential benefits of antenatal steroids in pregnancies in the late preterm period, and the management of respiratory distress syndrome in late preterm neonates.

Intubation at Birth Is Associated with Death after Pulmonary Hemorrhage in Very Low Birth Weight Infants

OBJECTIVE

This retrospective cohort study was performed to clarify the association between intubation in the delivery room and the mortality after pulmonary hemorrhage in very low birth weight infants (VLBWIs) during hospitalization.

METHODS

The study participants were screened from the VLBWIs admitted to the neonatal intensive care unit (NICU) of the Children's Hospital Affiliated to Nanjing Medical University from 31 July 2019 to 31 July 2022. The newborns who ultimately were included were those infants who survived until pulmonary hemorrhage was diagnosed. These subjects were divided into the intubation-at-birth group (n = 29) and the non-intubation-at-birth group (n = 35), retrospectively.

RESULTS

Univariate analysis found that the intubation group had a higher mortality and shorter hospital stay than the non-intubation group (p < 0.05) (for mortality: 25/29 (86.21%) in intubation group versus 14/35 (40.00%) in non-intubation group). By multivariate analysis, the result further showed that intubation in the delivery room was related to shorter survival time and higher risk of death (adjusted hazard ratio: 2.341, 95% confidence interval: 1.094-5.009).

CONCLUSIONS

Intubation at birth suggested a higher mortality in the VLBWIs when pulmonary hemorrhage occurred in the NICU.

National Trends in Survival and Short-Term Outcomes of Periviable Births ≤24 Weeks Gestation in the United States, 2009 to 2018

OBJECTIVE

Data from the academic medical centers in the United States showing improvements in survival of periviable infants born at 22 to 24 weeks GA may not be nationally representative since a substantial proportion of preterm infants are cared for in community hospital-based neonatal intensive care units. Our objective was to examine the national trends in survival and other short-term outcomes among preterm infants born at ≤24 weeks gestational age (GA) in the United States from 2009 to 2018.

STUDY DESIGN

This was a retrospective, repeated cross-sectional analysis of the National Inpatient Sample for preterm infants ≤24 weeks GA. The primary outcome was the trends in survival to discharge. Secondary outcomes were the trends in the composite outcome of death or one or more major morbidity (bronchopulmonary dysplasia, necrotizing enterocolitis stage ≥2, periventricular leukomalacia, severe intraventricular hemorrhage, and severe retinopathy of prematurity). The Cochran-Armitage trend test was used for trend analysis. p-Value <0.05 was considered significant.

RESULTS

Among 71,854 infants born at ≤24 weeks GA, 34,251 (47.6%) survived less than 1 day and were excluded. Almost 93% of those who survived <1 day were of ≤23 weeks GA. Among the 37,603 infants included in the study cohort, 48.1% were born at 24 weeks GA. Survival to discharge at GA ≤ 23 weeks increased from 29.6% in 2009 to 41.7% in 2018 (p < 0.001), while survival to discharge at GA 24 weeks increased from 58.3 to 65.9% (p < 0.001). There was a significant decline in the secondary outcomes among all the periviable infants who survived ≥1 day of life.

CONCLUSION

Survival to discharge among preterm infants ≤24 weeks GA significantly increased, while death or major morbidities significantly decreased from 2009 to 2018. The postdischarge survival, health care resource use, and long neurodevelopmental outcomes of these infants need further investigation.

KEY POINTS

· Survival increased significantly in infants ≤24 weeks GA in the United States from 2009 to 2018.. · Death or major morbidity in infants ≤24 weeks GA decreased significantly from 2009 to 2018.. · Death or surgical procedures including tracheostomy, VP shunt placement, and PDA surgical closure in infants <=24 weeks GA decreased significantly from 2009 to 2018..

Risk Factors for Pneumothorax and Its Association with Ventilation in Neonates

OBJECTIVE

The mode of ventilation that is implicated in pneumothorax is the one at the time of its diagnosis. Although there is evidence that air leak starts many hours before it is clinically evident, there are no prior studies that have investigated the association of pneumothorax with the mode of ventilation few hours before rather than at the time of its diagnosis.

STUDY DESIGN

A retrospective case-control study was conducted in the neonatal intensive care unit (NICU) between 2006 and 2016 where cases of neonates with pneumothorax were compared with gestational age-matched control neonates without pneumothorax. Respiratory support associated with pneumothorax was classified as the mode of ventilation 6 hours before the clinical diagnosis of pneumothorax. We investigated the factors that were different between cases and controls, and between cases of pneumothorax on bubble continuous positive airway pressure (bCPAP) and invasive mechanical ventilation (IMV).

RESULT

Of the 8,029 neonates admitted in the NICU during the study period, 223 (2.8%) developed pneumothorax. Among these, 127 occurred among 2,980 (4.3%) neonates on bCPAP, 38 among 809 (4.7%) neonates on IMV, and the remaining 58 among 4,240 (1.3%) neonates on room air. Those with pneumothorax were more likely to be male, have higher body weight, require respiratory support and surfactant administration, and have bronchopulmonary dysplasia (BPD). Among those who developed pneumothorax, there were differences in the gestational age, gender, and use of antenatal steroids between those who were on bCPAP as compared to those on IMV. IMV was associated with increased odds of pneumothorax as compared to those on bCPAP in a multivariable regression analysis. Cases on IMV had higher incidence of intraventricular hemorrhage, retinopathy of prematurity, BPD, and necrotizing enterocolitis, as well as longer length of stay as compared to those on bCPAP.

CONCLUSION

Neonates who require any respiratory support have higher incidence of pneumothorax. Among those on respiratory support, those on IMV had higher odds of pneumothorax and worse clinical outcomes as compared to those on bCPAP.

KEY POINTS

· The process of air leak leading to pneumothorax in majority of neonates starts much before it is clinically diagnosed.. · It is possible to detect the air leak early in the process by subtle changes in the signs, symptoms and changes in lung function.. · True association of the ventilation associated with pneumothorax is not at the time of diagnosis of pneumothorax but few hours before it is diagnosed.. · There is higher incidence of pneumothorax in neonates on any respiratory support.. · There is significantly higher incidence of pneumothorax among neonates on invasive ventilations as compared to noninvasive ventilation after correction for all other clinical factors..

Advanced Diagnostics of Respiratory Distress Syndrome in Premature Infants Treated with Surfactant and Budesonide through Computer-Assisted Chest X-ray Analysis

This research addresses the respiratory distress syndrome (RDS) in preterm newborns caused by insufficient surfactant synthesis, which can lead to serious complications, including pneumothorax, pulmonary hypertension, and pulmonary hemorrhage, increasing the risk of a fatal outcome. By analyzing chest radiographs and blood gases, we specifically focus on the significant contributions of these parameters to the diagnosis and analysis of the recovery of patients with RDS. The study involved 32 preterm newborns, and the analysis of gas parameters before and after the administration of surfactants and inhalation corticosteroid therapy revealed statistically significant changes in values of parameters such as FiO2, pH, pCO2, HCO3, and BE (Sig. < 0.05), while the pO2 parameter showed a potential change (Sig. = 0.061). Parallel to this, the research emphasizes the development of a lung segmentation algorithm implemented in the MATLAB programming environment. The key steps of the algorithm include preprocessing, segmentation, and visualization for a more detailed understanding of the recovery dynamics after RDS. These algorithms have achieved promising results, with a global accuracy of 0.93 ± 0.06, precision of 0.81 ± 0.16, and an F-score of 0.82 ± 0.14. These results highlight the potential application of algorithms in the analysis and monitoring of recovery in newborns with RDS, also underscoring the need for further development of software solutions in medicine, particularly in neonatology, to enhance the diagnosis and treatment of preterm newborns with respiratory distress syndrome.

Descriptive and Functional Genomics in Neonatal Respiratory Distress Syndrome: From Lung Development to Targeted Therapies

In this up-to-date study, we first aimed to highlight the genetic and non-genetic factors associated with respiratory distress syndrome (RDS) while also focusing on the genomic aspect of this condition. Secondly, we discuss the treatment options and the progressing therapies based on RNAs or gene therapy. To fulfill this, our study commences with lung organogenesis, a highly orchestrated procedure guided by an intricate network of conserved signaling pathways that ultimately oversee the processes of patterning, growth, and differentiation. Then, our review focuses on the molecular mechanisms contributing to both normal and abnormal lung growth and development and underscores the connections between genetic and non-genetic factors linked to neonatal RDS, with a particular emphasis on the genomic aspects of this condition and their implications for treatment choices and the advancing therapeutic approaches centered around RNAs or gene therapy.

Ultrasound diagnosis and grading criteria of neonatal respiratory distress syndrome

Background: Respiratory distress syndrome (RDS) is a common critical lung disease in newborn infants, especially those in premature infants with higher mortality rate. Early and correct diagnosis is the key to improve its prognosis. Previously, the diagnosis of RDS mainly relied on chest X-ray (CXR) findings, and it has been graded into four stages based on the progression and severity of CXR changes. This traditional diagnosing and grading method may lead to high misdiagnosis rate or delayed diagnosis. Recently, using ultrasound to diagnose neonatal lung diseases and RDS is becoming increasingly popular, and the technology is gaining higher sensitivity and higher specificity. The management of RDS under lung ultrasound (LUS) monitoring has achieved significant results, reducing the misdiagnosis rate of RDS, thereby reducing the probability of mechanical ventilation and the use of exogenous pulmonary surfactant, and making the success rate of treatment of RDS up to 100%.Objective: The purpose of the article was to introduce the ultrasound grading methods and criteria of RDS, in order to promote the application of LUS in the diagnosis and treatment of RDS.Methods: Literature (in English and Chinese) on the use of ultrasound in the diagnosis of neonatal RDS between 2008 and 2022 was selected for inclusion in this study.Results: From the collected literature, the use of ultrasound in the diagnosis of RDS is increasing, and people's understanding of the ultrasound imaging findings of RDS is also changing. Among them, the research on ultrasound grading of RDS is the latest progress.Conclusion: Ultrasound is accurate and reliable in the diagnosis and differential diagnosis of RDS. It is of great clinical value to master the ultrasound diagnosis and grading criteria of RDS.

Dose pulmonary hemorrhage increase the risk of bronchopulmonary dysplasia in very low birth weight infants?

OBJECTIVE

To evaluate the association between pulmonary hemorrhage and bronchopulmonary dysplasia (BPD) in very low birth weight infants (VLBWIs).

METHODS

The study participants were all VLBW newborns admitted from January 1, 2019 to December 31, 2021. The BPD subjects finally included were VLBWIs who survived until the diagnosis was established. This study was divided into pulmonary hemorrhage group (PH group, n = 35) and non-pulmonary hemorrhage group (Non-PH group, n = 190).

RESULTS

By univariate analysis it was found that premature rupture of membranes, tracheal intubation in the delivery room, duration of mechanical ventilation, course of invasive ventilation (≥3 courses), pulmonary surfactant (>1 dose), medically and surgically treated patent ductus arteriosus, grade III-IV RDS, early onset sepsis, BPD and moderate to severe BPD showed significant differences between groups (p < .05). By Multivariate analysis, pulmonary hemorrhage did not increase the risks of BPD and moderate to severe BPD (adjusted OR for BPD = 1.710, 95% CI 0.581-5.039; adjusted OR for moderate to severe BPD = 2.401, 95% CI 0.736-7.834).

CONCLUSION

It suggests that pulmonary hemorrhage is not associated with the development of BPD and moderate to severe BPD in VLBWIs.

Cumulative evidence of the genetic association between SP-B C1580T polymorphisms and risk of neonatal respiratory distress syndrome

Objective: Surfactant protein SP-B, an important protein in pulmonary surfactant, is required for the stabilization of surfactant films in the lung and maintenance of postnatal lung function. Although the association between SP-B polymorphisms and the risk of neonatal respiratory distress syndrome (RDS) has been evaluated, the results have been inconsistent. We investigated the association between SP-B polymorphisms and the risk of neonatal RDS.Methods: Relevant studies were systematically searched in PubMed, EMBASE, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) electronic databases until June 2022. Data were collected independently by two reviewers and converted to odds ratios (ORs) with 95% confidence intervals (CIs). Meta-analysis, subgroup analysis, sensitivity analysis, and publication bias assessment were performed using Stata 12.1 software and Review Manager 5.3.Results: Fourteen studies were included. SP-B C1580T polymorphism was significantly associated with neonatal RDS in five genetic models (T vs. C: OR = 0.70, 95% CI 0.57-0.86, I² = 78%; TT vs. CC: OR = 0.63, 95% CI 0.53-0.86, I² = 39%; CT vs. CC: OR = 0.65, 95% CI 0.50-0.84, I² = 54%; TT + CT vs. CC: OR = 0.62, 95% CI 0.49-0.78, I² = 59%; TT vs. CC + CT: OR = 0.78, 95% CI 0.67-0.91, I² = 43%). The CT and TT genotypes may decrease the risk of RDS in neonates. Subgroup analyses revealed that the association of SP-B C1580T polymorphism with neonatal RDS was stable, independent of preterm birth and Hardy-Weinberg equilibrium. In addition, the Han Chinese were more likely to be affected by SP-B C1580T polymorphisms than Caucasians and Finnish.Conclusions: Our findings suggest that SP-B C1580T polymorphism may be a protective factor against neonatal RDS.

Effect of different courses and durations of invasive mechanical ventilation on respiratory outcomes in very low birth weight infants

This multicenter retrospective study was conducted to explore the effects of different courses and durations of invasive mechanical ventilation (MV) on the respiratory outcomes of very low birth weight infants (VLBWI) in China. The population for this study consisted of infants with birth weight less than 1500 g needing at least 1 course of invasive MV and admitted to the neonatal intensive care units affiliated with the Chinese Neonatal Network within 6 h of life from January 1st, 2019 to December 31st, 2020. Univariate and multivariate logistic regression analyses were performed to evaluate associations between invasive MV and respiratory outcomes. Adjusted odds ratios (ORs) were computed with the effects of potential confounders. (1) Among the 3183 VLBWs with a history of at least one course of invasive MV, 3155 (99.1%) met inclusion criteria and were assessed for the primary outcome. Most infants received one course (76.8%) and a shorter duration of invasive MV (62.16% with ventilation for 7 days or less). (2) In terms of the incidence of all bronchopulmonary dysplasia (BPD) (mild, moderate, and severe BPD), there were no significant differences between different invasive MV courses [For 2 courses, adjusted OR = 1.11 (0.88, 1.39); For 3 courses or more, adjusted OR = 1.07 (0.72, 1.60)]. But, with the duration of invasive MV prolonging, the OR of BPD increased [8-21 days, adjusted OR = 1.98 (1.59, 2.45); 22-35 days, adjusted OR = 4.37 (3.17, 6.03); ≥ 36 days, adjusted OR = 18.44 (10.98, 30.99)]. Concerning severe BPD, the OR increased not only with the course of invasive MV but also with the duration of invasive MV [For 2 courses, adjusted OR = 2.17 (1.07, 4.40); For 3 courses or more, adjusted OR = 2.59 (1.02, 6.61). 8-21 days, adjusted OR = 8.42 (3.22, 22.01); 22-35 days, adjusted OR = 27.82 (9.08, 85.22); ≥ 36 days, adjusted OR = 616.45 (195.79, > 999.999)]. (3) When the interaction effect between invasive MV duration and invasive MV course was considered, it was found that there were no interactive effects in BPD and severe BPD. Greater than or equal to three courses would increase the chance of severe BPD, death, and the requirement of home oxygen therapy. Compared with distinct courses of invasive MV, a longer duration of invasive MV (> 7 days) has a greater effect on the risk of BPD, severe BPD, death, and the requirement of home oxygen therapy.

Noninvasive Respiratory Support Effects on Sighs in Preterm Infants by Electrical Impedance Tomography

OBJECTIVE

To evaluate differences regarding sigh frequency between noninvasive respiratory support types and to assess regional ventilation distribution, delta Z, and end-expiratory lung impedance differences before and after sighs.

METHODS

Very low-birth-weight infants with gestational ages less than 32 wk were included in the study. Participants were split into two groups: those receiving continuous positive airway pressure and infants receiving high-flow nasal cannula therapy.

RESULTS

The study enrolled 30 infants. The high-flow nasal cannula therapy group had more sighs per 10-min period than infants receiving continuous positive airway pressure (p = 0.016). Ventilation distribution was similar in the anterior and right ventilation distribution compartments pre- and post-sigh (46.30% vs. 45.68% and 54.27% vs. 55.26%, respectively). No statistically significant increase in end-expiratory lung impedance or delta Z was observed in global or separate lung regions (p > 0.05).

CONCLUSION

The study has demonstrated that sighs are more frequent in infants receiving high-flow nasal cannula respiratory support compared to continuous positive airway pressure. Spontaneously occurring sighs on noninvasive respiratory support due to respiratory distress syndrome (RDS) do not increase end-expiratory lung impedance or alter delta Z, and appear to have limited clinical significance.

TRIAL REGISTRATION

Prospectively registered at www.

CLINICALTRIALS

gov , reg. No. NCT04542096, reg. date 01/09/2020.

Neonatal heavy metals levels are associated with the severity of neonatal respiratory distress syndrome: a case–control study

Background

This case–control study aimed to compare lead (Pb), cadmium (Cd), and arsenic (As) levels in neonates with respiratory distress syndrome (NRDS) with those levels in normal neonates and tested their associations with the severity of NRDS indicated by the levels of serum surfactant protein D (SP-D) and cord blood cardiac troponin I (CTnI), and high-sensitive C-reactive protein (hs-CRP).

Methods

The study included two groups: G1 (60 healthy neonates) and G2 (100 cases with NRDS). Cord blood Pb, erythrocytic Cd (E-Cd), neonatal scalp hair As (N-As), maternal urinary Cd (U-Cd), and arsenic (U-As) were measured by a Thermo Scientific iCAP 6200, while CTnI, hs-CRP, and SP-D by their corresponding ELISA kits.

Results

The levels of cord blood Pb, E-Cd, N-As, U-Cd, U-As, SP-D, CTnI, and hs-CRP were significantly higher in G2 than G1 (p = 0.019, 0.040, 0.003, 0.010, 0.011, < 0.001, 0.004, < 0.001, respectively). While the birth weight, and APGAR score at 1, 5 and 10 min were significantly lower in G2 than G1 (p = 0.002, < 0.001, < 0.001, < 0.001, respectively). The levels of the studied heavy metals correlated positively with the levels of SP-D, CTnI, and hs-CRP.

Conclusion

Heavy metals toxicity may be accused to be one of the causes of NRDS especially if other apparent causes are not there. Measuring and follow-up of heavy metal levels should be considered during pregnancy.

[Pulmonary hemorrhage in very low birth weight infants: risk factors and clinical outcome]

OBJECTIVES

To investigate the risk factors for pulmonary hemorrhage and its clinical outcome in very low birth weight infants (VLBWIs).

METHODS

The medical data were collected from all live VLBWIs (gestational age <35 weeks) who were admitted to Jiangsu Women and Children Health Hospital and Children's Hospital of Nanjing Medical University between January 1, 2020 and December 31, 2021. Based on inclusion and exclusion criteria, 574 VLBWIs were included in the study, with 44 VLBWIs in the pulmonary hemorrhage group and 530 VLBWIs in the non-pulmonary hemorrhage group. The clinical data were compared between the two groups. A multivariate logistic regression analysis was used to identify the risk factors for pulmonary hemorrhage.

RESULTS

There were significant differences between the two groups in maternal age, rate of positive-pressure ventilation for resuscitation, rate of tracheal intubation for resuscitation, and minimum body temperature within 1 hour after birth (P<0.05). The pulmonary hemorrhage group had a higher proportion of VLBWIs with grade Ⅲ-Ⅳ respiratory distress syndrome or early-onset sepsis than the non-pulmonary hemorrhage group (P<0.05). The pulmonary hemorrhage group also had a higher proportion of VLBWIs with a capillary refilling time of >3 seconds within 1 hour after birth and with the maximum positive end-expiratory pressure (PEEP) of <5 cmH2O within 24 hours after birth (P<0.05). The multivariate regression analysis showed that maternal age of 30-<35 years (OR=0.115, P<0.05) was a protective factor against pulmonary hemorrhage, while a lower temperature (<34°C) within 1 hour after birth, the maximum PEEP of <5 cm H2O within 24 hours after birth, and early-onset sepsis were risk factors for pulmonary hemorrhage (OR=11.609, 11.118, and 20.661, respectively; P<0.05). For all VLBWIs, the pulmonary hemorrhage group had a longer duration of invasive ventilation and a higher mortality rate than the non-pulmonary hemorrhage group (P<0.05); for the survival VLBWIs, the pulmonary hemorrhage group had a higher incidence rate of bronchopulmonary dysplasia than the non-pulmonary hemorrhage group (P<0.05).

CONCLUSIONS

Maintaining the stability of temperature, giving appropriate PEEP, and identifying sepsis as early as possible can reduce the incidence rate of pulmonary hemorrhage, thereby helping to reduce the incidence of bronchopulmonary dysplasia and mortality in VLBWIs.

Plasma apelin and vascular endothelial growth factor levels in preterm infants: relationship to neonatal respiratory distress syndrome

AIM

The study aimed to determine the association between cord plasma levels of apelin and vascular endothelial growth factor (VEGF) with respiratory distress syndrome (RDS) in preterm infants.

METHODS

This case-control study included 120 preterm infants admitted to the neonatal intensive care unit of our hospital between January 2019 and January 2020. The infants were divided into RDS (n = 60) and non-RDS groups (n = 60). The cord plasma apelin and VEGF levels, perinatal characteristics, and neonatal complications were compared between the two groups.

RESULTS

The plasma apelin levels in the RDS group were significantly higher than in the non-RDS group (158.9 ± 24.8 vs. 125.2 ± 18.2 pg/mL, respectively), whereas VEGF levels in the non-RDS group were significantly higher than in the RDS group (187.4 ± 28.5 vs. 245.1 ± 44.8 pg/mL, respectively) (both p < .001). Infants with more severe RDS had higher plasma apelin levels and lower plasma VEGF levels. In the receiver operating characteristic curve analysis for the prediction of RDS, a cutoff of 148.4 pg/mL for apelin level yielded a sensitivity of 63.3% and a specificity of 95.0%, whereas a cutoff of 214.2 pg/mL for VEGF level showed a sensitivity of 86.7% and a specificity of 75.0%. Apelin levels were negatively correlated with VEGF levels in infants with RDS (r = 0.84, p < .001).

CONCLUSION

Differences in cord plasma apelin and VEGF levels may aid in the early diagnosis and treatment of RDS in preterm infants.

Clusters of preterm live births and respiratory distress syndrome-associated neonatal deaths: spatial distribution and cooccurrence patterns

Background

Prematurity and respiratory distress syndrome (RDS) are strongly associated. RDS continues to be an important contributor to neonatal mortality in low- and middle-income countries. This study aimed to identify clusters of preterm live births and RDS-associated neonatal deaths, and their cooccurrence pattern in São Paulo State, Brazil, between 2004 and 2015. 

Methods

Population-based study of all live births with gestational age ≥ 22 weeks, birthweight ≥ 400 g, without congenital anomalies from mothers living in São Paulo State, Brazil, during 2004–2015. RDS-associated neonatal mortality was defined as deaths < 28 days with ICD-10 codes P22.0 or P28.0. RDS-associated neonatal mortality and preterm live births rates per municipality were submitted to first- and second-order spatial analysis before and after smoothing using local Bayes estimates. Spearman test was applied to identify the correlation pattern between both rates.

Results

Six hundred forty-five thousand two hundred seventy-six preterm live births and 11,078 RDS-associated neonatal deaths in São Paulo State, Brazil, during the study period were analyzed. After smoothing, a non-random spatial distribution of preterm live births rate (I = 0.78; p = 0.001) and RDS-associated neonatal mortality rate (I = 0.73; p = 0.001) was identified. LISA maps confirmed clusters for both, with a negative correlation (r = -0.24; p = 0.0000). Clusters of high RDS-associated neonatal mortality rates overlapping with clusters of low preterm live births rates were detected.

Conclusions

Asymmetric cluster distribution of preterm live births and RDS-associated neonatal deaths may be helpful to indicate areas for perinatal healthcare improvement.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13629-4.

Clinical effect of different maintenance doses of caffeine citrate in the treatment of preterm infants requiring assisted ventilation: a pilot multicenter study

OBJECTIVES

To explore the optimal maintenance dose of caffeine citrate for preterm infants requiring assisted ventilation and caffeine citrate treatment.

METHODS

A retrospective analysis was performed on the medical data of 566 preterm infants (gestational age ≤34 weeks) who were treated and required assisted ventilation and caffeine citrate treatment in the neonatal intensive care unit of 30 tertiary hospitals in Jiangsu Province of China between January 1 and December 31, 2019. The 405 preterm infants receiving high-dose (10 mg/kg per day) caffeine citrate after a loading dose of 20 mg/kg within 24 hours after birth were enrolled as the high-dose group. The 161 preterm infants receiving low-dose (5 mg/kg per day) caffeine citrate were enrolled as the low-dose group.

RESULTS

Compared with the low-dose group, the high-dose group had significant reductions in the need for high-concentration oxygen during assisted ventilation (P=0.044), the duration of oxygen inhalation after weaning from noninvasive ventilation (P<0.01), total oxygen inhalation time during hospitalization (P<0.01), the proportion of preterm infants requiring noninvasive ventilation again (P<0.01), the rate of use of pulmonary surfactant and budesonide (P<0.05), and the incidence rates of apnea and bronchopulmonary dysplasia (P<0.01), but the high-dose group had a significantly increased incidence rate of feeding intolerance (P=0.032). There were no significant differences between the two groups in the body weight change, the incidence rates of retinopathy of prematurity, intraventricular hemorrhage or necrotizing enterocolitis, the mortality rate, and the duration of caffeine use (P>0.05).

CONCLUSIONS

This pilot multicenter study shows that the high maintenance dose (10 mg/kg per day) is generally beneficial to preterm infants in China and does not increase the incidence rate of common adverse reactions. For the risk of feeding intolerance, further research is needed to eliminate the interference of confounding factors as far as possible.

Prenatal quantification of human foetal lung and liver elasticities between 24 and 39 weeks of gestation using 2D shear wave elastography

Objectives

To quantify and model normal foetal lung and liver elasticities between 24 and 39 weeks of gestation (WG) using two-dimensional shear wave elastography (2D-SWE). To assess the impact of the distance between the probe and the target organ on the estimation of elasticity values.

Methods

Measurements of normal foetal lungs and liver elasticity were prospectively repeated monthly between 24 and 39 WG in 72 foetuses using 2D-SWE. Elasticity was quantified in the proximal lung and in the region inside the hepatic portal sinus. The distance between the probe and the target organ was recorded. Trajectories representing foetal lung and liver maturation from at least 3 measurements over time were modelled.

Results

The average elasticity for the lung and liver was significantly different from 24 WG to 36 WG (p < 0.01). Liver elasticity increased during gestation (3.86 kPa at 24 WG versus 4.45 kPa at 39 WG). From 24 WG to 32 WG, lung elasticity gradually increased (4.12kPa at 24 WG, 4.91kPa at 28 WG, 5.03kPa at 32 WG, p < 0.002). After 32 WG, lung elasticity decreased to 4.54kPa at 36 WG and 3.94kPa at 39 WG. The dispersion of the average elasticity values was greater for the lung than for the liver (p < 0.0001). Variation in the elasticity values was less important for the liver than for the lung. The values were considered valid and repeatable except for a probe-lung distance above 8cm.

Conclusion

Foetal lung and liver elasticities evolve differently through gestation. This could reflect the tissue maturation of both organs during gestation.

Trial registration

clinicaltrials.gov identifier: NCT03834805

Key Points

• Prenatal quantification of foetal lung elasticity using 2D shear wave elastography could be a new prenatal parameter for exploring foetal lung maturity.

• Liver elasticity increased progressively from 24 weeks of gestation (WG) to 39 WG, while lung elasticity increased first between 24 and 32 WG and then decreased after 32 WG.

• The values of elasticity are considered valid and repeatable except for a probe-lung distance above 8cm.

Gastrostomy Tube Placement and Resource Use in Neonatal Hospitalizations With Down Syndrome

OBJECTIVES

To determine the trends in gastrostomy tube (GT) placement and resource utilization in neonates ≥35 weeks' gestational age with Down syndrome (DS) in the United States from 2006 to 2017.

METHODS

This was a serial cross-sectional analysis of neonatal hospitalizations of ≥35 weeks' gestational age with International Classification of Diseases diagnostic codes for DS within the National Inpatient Sample. International Classification of Diseases procedure codes were used to identify those who had GT. The outcomes of interest were the trends in GT and resource utilization and the predictors of GT placement. Cochran-Armitage and Jonckheere-Terpstra trend tests were used for trend analysis of categorical and continuous variables, respectively. Predictors of GT placement were identified using multivariable logistic regression. P value <.05 was considered significant.

RESULTS

Overall, 1913 out of 51 473 (3.7%) hospitalizations with DS received GT placement. GT placement increased from 1.7% in 2006 to 5.6% in 2017 (P <.001), whereas the prevalence of DS increased from 10.3 to 12.9 per 10 000 live births (P <.001). Median length of stay significantly increased from 35 to 46 days, whereas median hospital costs increased from $74 214 to $111 360. Multiple comorbidities such as prematurity, sepsis, and severe congenital heart disease were associated with increased odds of GT placement.

CONCLUSIONS

There was a significant increase in GT in neonatal hospitalizations with DS, accompanied by a significant increase in resource utilization. Multiple comorbidities were associated with GT placement and the early identification of those who need GT could potentially decrease length of stay and resource use.

Temporal trends in respiratory care and bronchopulmonary dysplasia in very preterm infants over a 10-year period in Spain

OBJECTIVE

To evaluate trends in respiratory care practices and bronchopulmonary dysplasia (BPD) among very preterm infants born in Spain between 2010 and 2019.

STUDY DESIGN

This was a retrospective cohort study of data obtained from a national population-based database (SEN1500 network). Changes in respiratory care and BPD-free survival of infants with gestational age (GA) of 23⁰-31⁶ weeks and <1500 g were assessed over two 5-year periods. Temporal trends were examined by joinpoint and Poisson regression models and expressed as the annual per cent change and adjusted relative risk (RR) for the change per year.

RESULTS

A total of 17 952 infants were included. In the second period, infants were less frequently intubated in the delivery room and during neonatal intensive care unit stay. This corresponded with an increase in use of non-invasive ventilation techniques. There were no significant differences between the periods in BPD-free survival or survival without moderate-to-severe BPD. After adjusting for covariates, the RR for the change per year was significant for the following variables: never intubated (RR 1.03, 95% CI 1.02 to 1.04); intubation in the delivery room (RR 0.98, 95% CI 0.97 to 0.99); use of nasal intermittent positive pressure ventilation (RR 1.08, 95% CI 1.05 to 1.11); and BPD-free survival (only in the group with the lowest GA; RR 0.98, 95% CI 0.97 to 0.99).

CONCLUSION

Our findings reveal significant changes in respiratory care practices between 2009 and 2019. Despite an increase in use of non-invasive respiratory strategies, BPD-free survival did not improve and even worsened in the group with the lowest GA (23⁰-25⁶).

Caregiver burden in cystic fibrosis: a systematic literature review

BACKGROUND

Cystic fibrosis (CF) affects more than 80,000 people worldwide, having a considerable impact on the quality of life of patients and their caregivers, who assist patients with time-consuming treatment regimens. Despite this, a review of the available evidence has not been previously undertaken. This systematic literature review aimed to identify the humanistic and economic burdens of CF on caregivers.

METHODS

A systematic literature review was conducted, in accordance with Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Publications reporting outcomes for the caregivers of people with CF, including utility data, health status, and occupational impact, were reviewed. Sources searched were Embase (OvidSP), Medline (PubMed), the Cochrane Database of Systematic Reviews, and the Epistemonikos database, from 2010 to March 2020. A subsequent search with updated terms identified articles up to April 2020. Electronic searches were supplemented by hand searches to capture all relevant literature.

RESULTS

A total of 889 articles reporting humanistic burden and 310 reporting economic burden were identified. Following full-text screening by two independent reviewers, 72 articles were included in the review, of which 65 and 17 reported data on humanistic and economic burdens, respectively, with 10 reporting on both. The reviewed literature covered several outcomes and identified multiple key findings: greater disease severity is associated with the reporting of greater caregiver burden and lower utility scores of quality of life; reduced patient lung function is associated with increased caregiver depression and anxiety; and caregiving causes significant occupational impact, with pulmonary exacerbations decreasing caregiver productivity by up to a third compared with the patient being in a 'well' state.

CONCLUSION

Findings from this systematic literature review highlight the substantial humanistic and economic burdens borne by the caregivers of people with CF. Future research would help to further inform on the link between disease severity and caregiver burden.

The Intertemporal Role of Respiratory Support in Improving Neonatal Outcomes: A Narrative Review

Defining improvements in healthcare can be challenging due to the need to assess multiple outcomes and measures. In neonates, although progress in respiratory support has been a key factor in improving survival, the same degree of improvement has not been documented in certain outcomes, such as bronchopulmonary dysplasia. By exploring the evolution of neonatal respiratory care over the last 60 years, this review highlights not only the scientific advances that occurred with the application of invasive mechanical ventilation but also the weakness of the existing knowledge. The contributing role of non-invasive ventilation and less-invasive surfactant administration methods as well as of certain pharmacological therapies is also discussed. Moreover, we analyze the cost-benefit of neonatal care-respiratory support and present future challenges and perspectives.

Optimizing respiratory management in preterm infants: a review of adjuvant pharmacotherapies

Adjuvant respiratory therapies in preterm neonates aim to reduce long-term morbidities and mortality. Commonly utilized therapies include caffeine, systemic glucocorticosteroids, inhaled steroids, inhaled bronchodilators, and diuretics. This review discusses the available literature that supports some of these practices and points out where clinical practices are not corroborated by evidence. Therapies with no proven clinical benefit must be weighed against potential adverse effects.

Malnutrition, poor post-natal growth, intestinal dysbiosis and the developing lung

In extremely preterm infants, poor post-natal growth, intestinal dysbiosis and bronchopulmonary dysplasia are common, and each is associated with long-term complications. The central hypothesis that this review will address is that these three common conditions are interrelated. Challenges to studying this hypothesis include the understanding that malnutrition and poor post-natal growth are not synonymous and that there is not agreement on what constitutes a normal intestinal microbiota in this evolutionarily new population. If this hypothesis is supported, further study of whether "correcting" intestinal dysbiosis in extremely preterm infants reduces postnatal growth restriction and/or bronchopulmonary dysplasia is indicated.

Aerosolized Surfactant for Preterm Infants with Respiratory Distress Syndrome

Currently, the administration of surfactant to preterm infants with respiratory distress syndrome (RDS) mainly relies on intratracheal instillation; however, there is increasing evidence of aerosolized surfactant being an effective non-invasive strategy. We present a historical narrative spanning sixty years of development of aerosolization systems. We also offer an overview of the pertinent mechanisms needed to create and manage the ideal aerosolization system, with a focus on delivery, distribution, deposition, and dispersion in the context of the human lung. More studies are needed to optimize treatment with aerosolized surfactants, including determination of ideal dosages, nebulizer types, non-invasive interfaces, and breath synchronization. However, the field is rapidly evolving, and widespread clinical use may be achieved in the near future.

Tracheostomy trends in preterm infants with bronchopulmonary dysplasia in the United States: 2008-2017

OBJECTIVE

To determine the trends in tracheostomy placement and resource use in preterm infants less than or equal to 30 weeks gestational age (GA) with bronchopulmonary dysplasia (BPD) in the United States from 2008 to 2017.

STUDY DESIGN

This was a retrospective, serial cross-sectional study using data from the NIS. Inclusion criteria were: GA less than or equal to 30 weeks, hospitalization at less than or equal to 28 days of age, assignment of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD9-CM) or ICD10-CM codes for BPD and tracheostomy. Trends in tracheostomy and resource utilization were assessed using Jonckheere-Terpstra test. p-value < .05 was considered significant.

RESULTS

Overall, 987 out of 68,953 (1.4%) hospitalizations with BPD had tracheostomy. Characteristics of the study population: 60.8% were male, 68.4% less than or equal to 26 weeks GA, 43.8% White, 60.5% with Medicaid or self-pay, 65.2% in the Midwest and South census regions of the United States, and 45.7% had gastrostomy tube placement. Tracheostomy placement (expressed as per 100,000 live births) decreased from 2.7 in 2008 to 1.9 in 2011. Thereafter, it increased from 1.9 in 2011 to 3.5 in 2017 (p < .001). GA less than or equal to 24 weeks was significantly associated with increased odds of tracheostomy placement. Median length of stay increased significantly from 170 to 231 days while median inflation adjusted hospital cost increased significantly from $323,091 in 2008-2009 to $687,141 between 2008-2009 and 2016-2017.

CONCLUSION

Although tracheostomy placement among preterm hospitalizations with BPD was rare, the frequency of its placement and its associated resource utilization significantly increased during the study period. Future studies should probe the reasons and factors behind these trends.

Risk factors for respiratory assistance in premature infants

Premature infants are prone to dyspnea after birth due to immature development, and some infants require respiratory assistance. However, the risk factors for respiratory assistance in premature infants are rarely reported. The present study enrolled 3,394 premature infants (665 infants had been provided with respiratory assistance and 2,729 had not used respiratory assistance) to retrospectively analyze the risk factors associated with respiratory aid. The multivariate logistic regression analysis demonstrated that placental abnormality [odds ratio (OR)=1.284; P=0.048], the male sex (OR=0.696; P=0.001), delivery via cesarean section (OR=1.538; P<0.001), low 1-min Apgar score (OR=0.727; P<0.001), low birth weight (OR=0.999; P=0.005) and low gestational age (OR=0.616; P<0.001) were independent risk factors for respiratory assistance in premature infants. Overall, a number of risk factors, including placental abnormality, cesarean section, low 1-min Apgar score, low birth weight and small gestational age, were identified for respiratory assistance in premature infants. By conducting a risk assessment of risk factors at birth and using this information to provide timely respiratory assistance, the survival rates of premature infants may increase.

Non-Invasive Ventilatory Strategies to Decrease Bronchopulmonary Dysplasia-Where Are We in 2021?

Recent advances in neonatology have led to the increased survival of extremely low-birth weight infants. However, the incidence of bronchopulmonary dysplasia (BPD) has not improved proportionally, partly due to increased survival of extremely premature infants born at the late-canalicular stage of lung development. Due to minimal surfactant production at this stage, these infants are at risk for severe respiratory distress syndrome, needing prolonged ventilation. While the etiology of BPD is multifactorial with antenatal, postnatal, and genetic factors playing a role, ventilator-induced lung injury is a major, potentially modifiable, risk factor implicated in its causation. Infants with BPD are at a higher risk of developing complications including sepsis, pulmonary arterial hypertension, respiratory failure, and death. Long-term problems include increased risk of hospital readmissions, respiratory infections, and asthma-like symptoms during infancy and childhood. Survivors who have BPD are also at increased risk of poor neurodevelopmental outcomes. While the ultimate solution for avoiding BPD lies in the prevention of preterm births, strategies to decrease its incidence are the need of the hour. It is time to focus on gentler modes of ventilation and the use of less invasive surfactant administration techniques to mitigate lung injury, thereby potentially decreasing the burden of BPD. In this article, we discuss the use of non-invasive ventilation in premature infants, with an emphasis on studies showing an effect on BPD with different modes of non-invasive ventilation. Practical considerations in the use of nasal intermittent positive pressure ventilation are also discussed, considering the significant heterogeneity in clinical practices and management strategies in its use.

Hospitalization charges for extremely preterm infants: a ten-year analysis in Shanghai, China

OBJECTIVES

Extreme prematurity exerts a substantial economic burden on families and societies worldwide, especially in developing countries with limited healthcare resources. This study aimed to estimate initial hospitalization charges after extremely preterm birth in China over the previous decade.

METHODS

A retrospective study was conducted in the largest tertiary neonatal intensive care unit in Shanghai, China, including 441 extremely preterm infants (gestational age <28 weeks) discharged between 2010 and 2019. Hospitalization data and medical charges were obtained from electronic inpatient medical records. Subgroup analysis was conducted to examine how the charges and length of stay varied by gestational age, discharge year, survival status, and major morbidities.

RESULTS

The median total hospitalization charge was $20,770.70 with a median length of stay of 70.0 days. Total and daily charges declined as gestational age increased. A rising trend was found over time for overall and daily medical charges. Compared with decedents, survivors had a longer length of stay and higher total hospitalization charges, but their charge per day was lower. Total hospitalization charges were significantly higher in infants with necrotizing enterocolitis (Stage II-III), bronchopulmonary dysplasia, and sepsis when compared with neonates of the same gestational age without these co-morbidities. Charges for treatments accounted for the highest proportion (31.3%).

LIMITATIONS

Local statistics collected retrospectively might limit generalizability to other regions. Long-term medical charges were not reported.

CONCLUSION

Economic burden of the initial hospitalization for extremely preterm infants was substantial in China. Such economic factors should be fully taken into account for perinatal consultations, medical insurance policy-making, and clinical decisions.

Intravenous sulforhodamine B reduces alveolar surface tension, improves oxygenation, and reduces ventilation injury in a respiratory distress model

In the neonatal respiratory distress syndrome (NRDS) and acute respiratory distress syndrome (ARDS), mechanical ventilation supports gas exchange but can cause ventilation-induced lung injury (VILI) that contributes to high mortality. Further, surface tension, T, should be elevated and VILI is proportional to T. Surfactant therapy is effective in NRDS but not ARDS. Sulforhodamine B (SRB) is a potential alternative T-lowering therapeutic. In anesthetized male rats, we injure the lungs with 15 min of 42 mL/kg tidal volume, V_T, and zero end-expiratory pressure ventilation. Then, over 4 h, we support the rats with protective ventilation-V_T of 6 mL/kg with positive end-expiratory pressure. At the start of the support period, we administer intravenous non-T-altering fluorescein (targeting 27 µM in plasma) without or with therapeutic SRB (10 nM). Throughout the support period, we increase inspired oxygen fraction, as necessary, to maintain >90% arterial oxygen saturation. At the end of the support period, we euthanize the rat; sample systemic venous blood for injury marker ELISAs; excise the lungs; combine confocal microscopy and servo-nulling pressure measurement to determine T in situ in the lungs; image fluorescein in alveolar liquid to assess local permeability; and determine lavage protein content and wet-to-dry ratio (W/D) to assess global permeability. Lungs exhibit focal injury. Surface tension is elevated 72% throughout control lungs and in uninjured regions of SRB-treated lungs, but normal in injured regions of treated lungs. SRB administration improves oxygenation, reduces W/D, and reduces plasma injury markers. Intravenous SRB holds promise as a therapy for respiratory distress.NEW & NOTEWORTHY Sulforhodmaine B lowers T in alveolar edema liquid. Given the problematic intratracheal delivery of surfactant therapy for ARDS, intravenous SRB might constitute an alternative therapeutic. In a lung injury model, we find that intravenously administered SRB crosses the injured alveolar-capillary barrier thus reduces T specifically in injured lung regions; improves oxygenation; and reduces the degree of further lung injury. Intravenous SRB administration might help respiratory distress patients, including those with the novel coronavirus, avoid mechanical ventilation or, once ventilated, survive.

Risk factors for treatment failure of heated humidified high-flow nasal cannula as an initial respiratory support in newborn infants with respiratory distress

BACKGROUND

Humidified high-flow nasal cannula (HHFNC) has gained popularity because it is easier to use, more comfortable for babies, and advantageous for mother-infant bonding. HHFNC is not inferior to other non-invasive ventilators for preventing adverse outcomes, but more studies are needed to ensure the safe use of HHFNC as an initial respiratory support for newborns. The aim of this study was to investigate risk factors for treatment failure of HHFNC as an initial respiratory support in newborns with respiratory distress after birth.

METHODS

We included 97 newborns who required non-invasive respiratory support within 24 h after birth. The success group included 68 infants who were successfully managed only on HHFNC, and 29 infants were the failure group who required other respiratory support because of respiratory acidosis, hypoxia, or apnea.

RESULTS

Compared with the success group, the failure group had lower GA, a higher rate of antenatal steroid use, prolonged rupture of membrane, lower pH, higher pCO₂ on blood-gas analysis after HHFNC application and higher incidence of respiratory distress syndrome of newborn (RDS). After adjusting for GA, higher FiO₂ settings during acidosis, hypercarbia after the application of HHFNC shown on blood-gas analysis and the presence of RDS remained significant. The rate of treatment failure was 16.2% for ≥36 weeks, 19.3% for ≥34 weeks, and 22.1% for ≥33 weeks.

CONCLUSION

Treatment failure of HHFNC should be considered a risk for newborns of less than 34 weeks and infants with respiratory distress from RDS. Higher FiO₂ settings during HHFNC, and acidosis and hypercarbia after the application of HHFNC shown on blood-gas analysis may help identify high-risk newborns for other non-invasive ventilators or intubation.

Extracorporeal Life Support in Pediatric Patients with Bronchopulmonary Dysplasia and Associated Pulmonary Hypertension

This retrospective study reviews outcomes of 281 pediatric patients with bronchopulmonary dysplasia (BPD) managed with extracorporeal life support (ECLS). Data from 1982 to 2018 from the Extracorporeal Life Support Organization (ELSO) registry were queried for children aged 60 days to 18 years with a prior diagnosis of BPD, and all patients with secondary pulmonary hypertension (PH) were identified. Overall survival of patients with and without PH was 86.7% and 68.0%, respectively (p = 0.23). There was no report of patients with PH before 2004. Patients with BPD + PH were more likely to have associated intraventricular hemorrhage (p = 0.002) and retinopathy of prematurity (p = 0.05), as well as a greater reported use of sildenafil (p = 0.0001) and milrinone (p = 0.008) before ECLS. The most common primary diagnosis in patients with BPD was viral respiratory infection (45.3%) and in patients with BPD + PH was respiratory failure without mention of infection (40.0%). Inotrope use was the most common complication reported (36.7%) with survival of 54.4%. We conclude that data from the ELSO registry demonstrate reasonable survival in both, patients with BPD and BPD + PH. Thus, patients with BPD and associated PH should be considered candidates for ECLS.

[Safety and efficacy of caffeine use started at different time in preterm infants: a multicenter study in Jiangsu Province, China]

OBJECTIVE

To study the efficacy and safety of caffeine used in the early (≤72 hours after birth) and late (>72 hours after birth) stage in preterm infants with a gestational age of ≤31 weeks.

METHODS

A retrospective analysis was performed for 640 preterm infants (with a gestational age of ≤31 weeks) who were admitted to the neonatal intensive care unit of eight hospitals in Jiangsu Province, China. Of the 640 preterm infants, 510 were given caffeine in the early stage (≤72 hours after birth; early use group) and 130 were given caffeine in the late stage (>72 hours after birth; late use group). The clinical data were compared between the two groups.

RESULTS

There were no significant differences in birth weight, Apgar score, sex, gestational age, and age on admission between the two groups (P>0.05). Compared with the late use group, the early use group had a significantly younger age at the beginning and withdrawal of caffeine treatment (P<0.05) and a significantly shorter duration of caffeine treatment (P<0.05). There was no significant difference in respiratory support on admission between the two groups (P>0.05). Compared with the late use group, the early use group had significantly lower incidence rate of apnea (P<0.05) and significantly shorter oxygen supply time and length of hospital stay (P<0.05). There were no significant differences between the two groups in the incidence rates of neonatal intracranial hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, retinopathy of prematurity, and patent ductus arteriosus at discharge and NBNA score at the corrected gestational age of 40 weeks (P>0.05). However, significant differences were found in the incidence of bronchopulmonary dysplasia and the rate of home oxygen therapy, but there was no significant difference in the mortality rate between the two groups (P>0.05).

CONCLUSIONS

Early use of caffeine can shorten the duration of caffeine treatment, oxygen supply time, and length of hospital stay, with little adverse effect, in preterm infants with a gestational age of ≤31 weeks.

Porcine versus bovine surfactant therapy for RDS in preterm neonates: pragmatic meta-analysis and review of physiopathological plausibility of the effects on extra-pulmonary outcomes

BACKGROUND

While porcine seems to be superior to bovine surfactants in terms of respiratory outcomes, it is unclear if a surfactant can improve extra-pulmonary outcomes in preterm neonates with respiratory distress syndrome and if there is any physiopathological/biological mechanism linking surfactant therapy to these outcomes. We aim to fill these knowledge gaps.

METHODS

Systematic and pragmatic review coupled with meta-analysis of randomized controlled trials of bovine or porcine surfactants administered to treat RDS in preterm neonates; common extra-pulmonary neonatal intensive care outcomes were considered. As additional analysis, animal or human translational studies about mechanisms linking surfactant replacement to extra-pulmonary neonatal outcomes were also systematically reviewed.

RESULTS

Porcine surfactant is associated with lower incidence of patent ductus arteriosus (OR:0.655; 95%CI:0.460-0.931); p = 0.018; 12 trials; 1472 patients); prenatal steroids (coeff.:-0.009, 95%CI:-0.03-0.009, p = 0.323) and gestational age (coeff.:0.079, 95%CI:-0.18-0.34, p = 0.554) did not influence this effect size. No significant differences were found between porcine and bovine surfactants on neonatal intensive care unit length of stay (mean difference (days):-2.977; 95%CI:-6.659-0.705; p = 0.113; 8 trials; 855 patients), intra-ventricular hemorrhage of any grade (OR:0.860; 95%CI:0.648-1.139); p = 0.293; 15 trials; 1703 patients), severe intra-ventricular hemorrhage (OR:0.852; 95%CI:0.624-1.163); p = 0.313; 15 trials; 1672 patients), necrotizing entero-colitis (OR:1.190; 95%CI:0.785-1.803); p = 0.412; 9 trials; 1097 patients) and retinopathy of prematurity (OR:0.801; 95%CI:0.480-1.337); p = 0.396; 10 trials; 962 patients).

CONCLUSIONS

Physiopathological mechanisms explaining the effect of surfactant have been found for patent ductus arteriosus only, while they are lacking for all other endpoints. Porcine surfactant is associated with lower incidence of PDA than bovine surfactants. As there are no differences in terms of other extra-pulmonary outcomes and no physiopathological plausibility, these endpoints should not be used in future trials.

REGISTRATION

PROSPERO n.CRD42018100906.

National Trends in the Epidemiology and Resource Use for Henoch-Schönlein Purpura (IgA Vasculitis) Hospitalizations in the United States From 2006 to 2014

OBJECTIVES

We examined the trends in the rate of Henoch-Schönlein purpura (HSP) hospitalizations and the associated resource use among children in the United States from 2006 through 2014.

METHODS

Pediatric hospitalizations with HSP were identified by using International Classification of Diseases, Ninth Revision, code 287.0 from the National Inpatient Sample. HSP hospitalization rate was calculated by using the US population as the denominator. Resource use was determined by length of stay (LOS) and hospital cost. We used linear regression for trend analysis.

RESULTS

A total of 16 865 HSP hospitalizations were identified, and the HSP hospitalization rate varied by age, sex, and race. The overall HSP hospitalization rate was 2.4 per 100 000 children, and there was no trend during the study period. LOS remained stable at 2.8 days, but inflation-adjusted hospital cost increased from $2802.20 in 2006 to $3254.70 in 2014 (P < .001).

CONCLUSIONS

HSP hospitalization rate in the United States remained stable from 2006 to 2014. Despite no increase in LOS, inflation-adjusted hospital cost increased. Further studies are needed to identify the drivers of increased hospitalization cost and to develop cost-effective management strategies.

Accuracy of oxygen saturation index in determining the severity of respiratory failure among preterm infants with respiratory distress syndrome

BACKGROUND

To evaluate the severity of respiratory failure among newborns with respiratory distress syndrome (RDS), oxygenation index (OI) has been implemented. In the present study, we assessed the accuracy of oxygen saturation index (OSI) in determining the severity of respiratory failure.

METHODS

A cross-sectional study was carried out in the NICUs of two Iranian Hospitals (Tehran, Iran) in 2018. Preterm neonates with RDS entered the study. Immediately after admission, the severity of RDS was determined based on RDS scoring system. Then, 2 CC of arterial blood was withdrawn and sent to laboratory determining blood gases. Simultaneously, the level of peripheral capillary oxygen saturation (SpO₂) was read using pulse oximeter and recorded. OI and OSI were measured using the formulae. Receiver Operating Characteristic curve, Kappa agreement coefficient and accuracy, sensitivity and specificity was used to compare the OI and OSI results.

RESULTS

In the study, 95 neonates were considered. Based on ROC curves, the appropriate cut off with AUC = 0.99 for severe respiratory failure was OSI >8. The sensitivity, specificity, negative predicted value, and positive predicted value for the OSI Cut off >8 were 100, 98, 0.97 and 100%, respectively. The overall accuracy and Kappa agreement between OSI and OI was 0.96 and 0.98%, respectively.

CONCLUSION

Our results showed that OSI with high sensitivity, specificity values could predict the severity of respiratory failure in preterm neonates with RDS.

Feasibility of two-dimensional ultrasound shear wave elastography of human fetal lungs and liver: A pilot study

PURPOSE

The first aim was to evaluate feasibility and reproducibility of 2-dimensional ultrasound (2D) shear wave elastography (SWE) of human fetal lungs and liver between 24 and 34weeks of gestation. The second aim was to model fetal lung-to-liver elastography ratio (LLE ratio) and to assess its variations according to gestational age and maternal administration of corticosteroids.

MATERIAL AND METHODS

2D-SWE examinations were prospectively performed in fetuses of women with an uncomplicated pregnancy (group 1) and fetuses of women with a threatened preterm labor requiring administration of corticosteroids (group 2). Two 2D-SWE examinations were performed at "day 0" and "day 2" in group 1; before and 24hours after a course of corticosteroid in group 2. Three operators performed 2 cycles of 3 measurements on the lung (regions A1, A2, A3) and the liver (regions IV, V, VI). Repeatability and reproducibility of measurements were calculated. The fetal LLE ratio was modeled from the most reproducible regions.

RESULTS

Fifty-five women were enrolled in group 1 and 48 in group 2. For the lung, 8.6% of measurements were considered invalid and 6.9% for the liver. The most reproducible region for the lung was A3 [ICC between 0.70 (95% CI: 0.42-0.85) and 0.78 (95% CI: 0.48-0.90)] and region VI for the liver [ICC between 0.70 (95% CI: 0.40-0.85) and 0.84 (95% CI: 0.60-0.94)]. According to gestational age, a moderate positive linear correlation was found for stiffness values of A3 (R=0.56), V (R=0.46) and VI (R=0.44). LLE ratio values at "day 0" were not different between the two groups but decreased at "day 2" in group 2 (0.2; 95% CI: 0.07-0.34; P<0.001).

CONCLUSION

Quantitative fetal lung and liver stiffness measurements are possible with 2D-SWE with acceptable reproducibility.