Prenatal diagnostic and intervention considerations in congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) is a life-threatening birth defect with significant morbidity and mortality. The prenatal management of a pregnancy with a fetus affected with CDH is complex and requires a multi-disciplinary team approach. An improved understanding of prenatal diagnosis and management is essential to developing strategies to optimize outcomes for these patients. In this review, we explore the current knowledge on diagnosis, severity stratification, prognostic prediction, and indications for fetal intervention in the fetus with CDH.

Congenital diaphragmatic hernia treated via fetal endoscopic tracheal occlusion improves outcome in a middle-income country.

OBJECTIVES: A recent European randomized trial - Tracheal Occlusion To Accelerate Lung Growth - demonstrated that fetoscopic endoluminal tracheal occlusion (FETO) is associated with increased postnatal survival among infants with severe congenital diaphragmatic hernia (CDH). However, this differs in middle-income countries such as Brazil, where abortion is illegal and neonatal intensive care is inadequate. This study evaluated the effects of FETO on improving the survival of infants with moderate-to-severe CDH in isolated and non-isolated cases. METHODS: This retrospective cohort study selected 49 fetuses with CDH, a normal karyotype, and a lung-to-head ratio (LHR) of <1 from a single national referral center for fetal surgery in São Paulo, Brazil, between January 2016 and November 2019. FETO was performed between 26 and 29 weeks of gestation. The primary outcomes were infant survival until discharge from the neonatal intensive care unit and survival until six months of age. RESULTS: Forty-six women with singleton fetuses having severe CDH underwent prenatal intervention with FETO. Infant survival rates until discharge and at six months of age were both 38 %. The observed-to-expected LHR increased by 25 % after FETO in neonates who survived until discharge. Spontaneous intrauterine death occurred in four growth-restricted fetuses after FETO. Preterm birth in <37 weeks and preterm rupture of membranes in <34 weeks occurred in 56.5 % (26) and 26 % (12) cases, respectively. CONCLUSIONS: FETO may increase neonatal survival in fetuses with severe CDH, particularly in countries with limited neonatal intensive care.

Fetoscopic Tracheal Occlusion for Isolated Severe Left Diaphragmatic Hernia: A Systematic Review and Meta-Analysis.

Background: We aimed to conduct a systematic review and meta-analysis to evaluate the fetoscopic tracheal occlusion in patients with isolated severe and left-sided diaphragmatic hernia. Methods: Cochrane Library, Embase, and PubMed (Medline) databases were searched from inception to February 2024 with no filters or language restrictions. We included studies evaluating the outcomes of fetoscopic intervention compared to expectant management among patients with severe congenital diaphragmatic hernia exclusively on the left side. A random-effects pairwise meta-analysis was performed using RStudio version 4.3.1. Results: In this study, we included 540 patients from three randomized trials and five cohorts. We found an increased likelihood of neonatal survival associated with fetoscopic tracheal occlusion (Odds Ratio, 5.07; 95% Confidence Intervals, 1.91 to 13.44; p < 0.01) across general and subgroup analyses. Nevertheless, there were higher rates of preterm birth (OR, 5.62; 95% CI, 3.47-9.11; p < 0.01) and preterm premature rupture of membranes (OR, 7.13; 95% CI, 3.76-13.54; p < 0.01) in fetal endoscopic tracheal occlusion group compared to the expectant management. Conclusions: Our systematic review and meta-analysis demonstrated the benefit of fetoscopic tracheal occlusion in improving neonatal and six-month postnatal survival in fetuses with severe left-sided CDH. Further studies are still necessary to evaluate the efficacy of tracheal occlusion for isolated right-sided CDH, as well as the optimal timing to perform the intervention.

Self-reported respiratory and gastrointestinal outcomes in children with isolated congenital diaphragmatic hernia: A prospective multicentre study.

OBJECTIVE: To evaluate medium-term self-reported respiratory and gastrointestinal (GI) outcomes in children with congenital diaphragmatic hernia (CDH). DESIGN: Self-reported respiratory and GI outcomes correlated with prenatal severity indicators. SETTING: Prospective study at three fetal medicine units. POPULATION: Families of children prenatally diagnosed with isolated, left-sided CDH surviving for >1 year. METHODS: Families received validated questionnaires for GI outcomes (Infant Gastroesophageal Reflux Questionnaire Revised, I-GERQ-R, for infants aged <2 years, or Paediatric Gastro-oesophageal Symptom and Quality of Life Questionnaire, PGSQ, for children aged aged 2-8 years or >9 years) and respiratory outcomes (preschool respiratory outcome questionnaire, for children aged ≤5 years, or the International Study of Asthma and Allergies in Childhood asthma questionnaire, for children aged 6-8 years or ≥9 years). Prenatal data collected from the medical records included lung size (percentage observed/expected lung-to-head ratio, O/E LHR %), liver position, fetal endoluminal tracheal occlusion (FETO) gestational age (GA) at delivery, and perinatal data included birthweight, location, patch repair and respiratory support. MAIN OUTCOME MEASURES: The GI and respiratory scores were correlated with O/E LHR using linear and logistic regression models. Univariate analysis was used to evaluate associations with perinatal variables. RESULTS: We obtained 142 responses from 342 families (representing a response rate of 45%). The baseline characteristics of participants and non-participants were comparable. No correlations between perinatal variables and respiratory or GI scores were identified. Children aged ≤5 years with lower O/E LHR values reported higher respiratory scores (P = 0.0175); this finding was not reported in older children. Overall, the children who underwent FETO (n = 51) had GI (P = 0.290) and respiratory (P = 0.052) scores that were comparable with those of children who were expectantly managed. CONCLUSIONS: Families and children with prenatally diagnosed CDH reported fewer respiratory symptoms with increasing age. There was no correlation between O/E LHR or the use of FETO and self-reported outcomes.

Management advances for congenital diaphragmatic hernia: integrating prenatal and postnatal perspectives.

In congenital diaphragmatic hernia (CDH), abdominal organs are displaced into the chest, compress the lungs, and cause mediastinal shift. This contributes to development of pulmonary hypoplasia and hypertension, which is the primary determinant of morbidity and mortality for affected newborns. The severity is determined using prenatal imaging as early as the first trimester and is related to the laterality of the defect, extent of lung compression, and degree of liver herniation. Comprehensive evaluation of fetal CDH includes imaging-based severity assessment, severity assessment, and evaluation for structural or genetic abnormalities to differentiate isolated from complex cases. Prenatal management involves multispecialty counseling, consideration for fetal therapy with fetoscopic endoluminal tracheal occlusion (FETO) for severe cases, monitoring and intervention for associated polyhydramnios or signs of preterm labor if indicated, administration of antenatal corticosteroids in the appropriate setting, and planned delivery to optimize the fetal condition at birth. Integrated programs that provide a smooth transition from prenatal to postnatal care produce better outcomes. Neonatal care involves gentle ventilation to avoid hyperinflation and must account for transitional physiology to avoid exacerbating cardiac dysfunction and decompensation. Infants who have undergone and responded to FETO have greater pulmonary capacity than expected, but cardiac dysfunction seems unaffected. In about 25-30% of CDH neonates extracorporeal life support is utilized, and this provides a survival benefit for patients with the highest predicted mortality, including those who underwent FETO. Surgical repair after initial medical management for the first 24-48 hours of life is preferred since later repair is associated with delayed oral feeding, increased need for tube feeds, and increased post-repair ventilation requirement and supplemental oxygen at discharge. With overall survival rates >70%, contemporary care involves management of chronic morbidities in the context of a multidisciplinary clinic setting.

Neurodevelopmental Outcomes in Children After Fetoscopic Endoluminal Tracheal Occlusion for Severe Congenital Diaphragmatic Hernia: Results From a Multidisciplinary Clinic.

BACKGROUND: We compared early neurodevelopmental morbidity in young children with severe CDH who underwent FETO to those without fetal therapy. METHODS: We conducted a prospective study of severe CDH patients undergoing FETO (n = 18) at a single North American center from 2015 to 2021 (NCT02710968). Outpatient survivors (n = 12) were evaluated by a multidisciplinary team and compared to expectantly managed CDH patients. Neurodevelopmental outcomes were assessed using the Capute Scales [Clinical Linguistic and Auditory Milestone Scales (CLAMS) and Cognitive Adaptive Test (CAT)], with a developmental quotient (DQ) < 85 indicative of at-risk for delay. RESULTS: At one year, 58% (n = 7) of FETO patients underwent evaluation, with notable concern for language delay (CLAMS median DQ, 80.1 [interquartile range, 67.6-86.7]). FETO scores improved by 24-months, whereas high severity/non-FETO scores declined [CLAMS median DQ (Difference in DQ), 92.3 (+12.2) vs. 77.1 (-13.4), respectively; p = 0.049]. On the initial CAT, FETO patients had concern for visual motor and problem-solving delays, with a median DQ of 81.3 (62.1-89.4). At 24-months, FETO patients had improving scores [Median CAT DQ, 90.8 (+9.5)], whereas high severity/non-FETO [87.5 (-3.0), p = 0.28] had declining scores. CONCLUSION: These initial data suggest that FETO is associated with favorable neurodevelopmental outcomes at 24-months compared to severe CDH under expectant management. LEVEL OF EVIDENCE: III.

Microinjection With Nanoparticles to Deliver Drugs in Prenatal Lung Explants - A Pilot Study for Prenatal Therapy in Congenital Diaphragmatic Hernia.

BACKGROUND: Fetoscopic endoluminal tracheal occlusion (FETO) improves the survival rate in fetuses with severe congenital diaphragmatic hernia (CDH). We hypothesize that prenatal therapies into the trachea during FETO can further improve outcomes. Here, we present an ex vivo microinjection technique with rat lung explants to study prenatal therapy with nanoparticles. METHODS: We used microsurgery to isolate lungs from rats on embryonic day 18. We injected chitosan nanoparticles loaded with fluorescein (FITC) into the trachea of the lung explants. We compared the difference in biodistribution of two types of nanoparticles, functionalized IgG-conjugated nanoparticles (IgG-nanoparticles) and bare nanoparticles after 24 h culture with immunofluorescence (IF). We used IF to mark lung epithelial cells with E-cadherin and to investigate an apoptosis (Active-caspase 3) and inflammatory marker (Interleukin, IL-6) and compared its abundance between the two experimental groups and control lung explants. RESULTS: We detected the presence of nanoparticles in the lung explants, and the relative number of nanoparticles to cells was 2.49 fold higher in IgG-nanoparticles than bare nanoparticles (p < 0.001). Active caspase-3 protein abundance was similar in the control, bare nanoparticles (1.20 fold higher), and IgG-nanoparticles (1.34 fold higher) groups (p = 0.34). Similarly, IL-6 protein abundance was not different in the control, bare nanoparticles (1.13 fold higher), and IgG-nanoparticles (1.12 fold higher) groups (p = 0.33). CONCLUSIONS: Functionalized nanoparticles had a higher presence in lung cells and this did not result in more apoptosis or inflammation. Our proof-of-principle study will guide future research with therapies to improve lung development prenatally. LEVELS OF EVIDENCE: N/A TYPE OF STUDY: Animal and laboratory study.

Surfactant Therapy in Congenital Diaphragmatic Hernia and Fetoscopic Endoluminal Tracheal Occlusion.

INTRODUCTION: Congenital diaphragmatic hernia (CDH) is a complex pathology with severe pulmonary morbidity. Administration of surfactant in CDH is controversial, and the advent of fetoscopic endoluminal tracheal occlusion (FETO) has added further complexity. While FETO has been shown to improve survival outcomes, there are risks of prematurity and potential surfactant deficiency. We aim to evaluate the characteristics and outcomes of surfactant administration for CDH infants and elucidate potential benefits or risks in this unique population. METHODS: A single-center retrospective cohort review of patients with unilateral CDH from September 2015 to July 2022 was performed. Demographics, prognostic perinatal imaging features, and outcomes were collected. Patients were stratified by surfactant administration and history of FETO. Data were analyzed with descriptive statistics, two-sample t-tests, chi-squared analyses, and logistic regression. RESULTS: Of 105 included patients, 19 (18%) underwent FETO and 25 (24%) received surfactant. Overall, surfactant recipients were born at earlier gestational ages and lower birthweights regardless of FETO history. Surfactant recipients possessed significantly worse prenatal prognostic features such as observed to expected total fetal lung volume, observed to expected lung to head ratio, and percent liver herniation. In CDH patients without FETO history, surfactant recipients demonstrated worse outcomes than nonrecipients. This association is notably absent in the FETO population, where surfactant recipients have more favorable survival and comparable outcomes. When controlling for defect severity or surfactant usage, as a proxy for respiratory status, surfactant recipients that underwent FETO trended toward improved survival and decreased ECMO use. CONCLUSIONS: Surfactant administration is not associated with increased morbidity and mortality and may be beneficial in CDH patients that have undergone FETO.

Fetoscopic endoluminal tracheal occlusion vs expectant management for fetuses with severe left-sided congenital diaphragmatic hernia.

BACKGROUND: The treatment of fetuses with a congenital diaphragmatic hernia is challenging, but there is evidence that fetoscopic endoluminal tracheal occlusion has a benefit over expectant care. In addition, standardization and expertism have a great impact on survival and are probably crucial in centers that rely on expectant management with extracorporeal membrane oxygenation after birth. OBJECTIVE: This study aimed to examine the survival and morbidity rates of fetuses with a severe isolated left-sided congenital diaphragmatic hernia who underwent fetoscopic endoluminal tracheal occlusion vs expectant management in high-volume centers. STUDY DESIGN: This was a multicenter, retrospective study that included all consecutive fetuses with severe isolated left-sided congenital diaphragmatic hernia who were expectantly managed in a German center or who underwent fetoscopic endoluminal tracheal occlusion in 3 other European centers (Belgium, France, and Italy). Severe congenital diaphragmatic hernia was defined as having an observed to expected total fetal lung volume ≤35% with intrathoracic position of the liver diagnosed with magnetic resonance imaging. All magnetic resonance images were centralized, and lung volumes were measured by 2 experienced operators who were blinded to the pre- and postnatal data. Multiple logistic regression analyses were performed to examine the effect of the management strategy in the 2 groups on the short- and long-term outcomes. RESULTS: A total of 147 patients who were managed expectantly and 47 patients who underwent fetoscopic endoluminal tracheal occlusion were analyzed. Fetuses who were managed expectantly had lower observed to expected total fetal lung volumes (20.6%±7.5% vs 23.7%±6.8%; P=.013), higher gestational age at delivery (median weeks of gestation, 37.4; interquartile range, 36.6-38.00 vs 35.1; interquartile range, 33.1-37.2; P<.001), and more frequent use of extracorporeal membrane oxygenation (55.8% vs 4.3%; P<.001) than the fetuses who underwent fetoscopic endoluminal tracheal occlusion. The survival rates at discharge and at 2 years of age in the expectant management group were higher than the survival rates of the fetoscopic endoluminal tracheal occlusion group (74.3% vs 44.7%; P=.001 and 72.8% vs 42.5%; P=.001, respectively). After adjustment for maternal age, gestational age at birth, observed to expected total fetal lung volume, and birth weight Z-score, the odds ratios were 4.65 (95% confidence interval, 1.9-11.9; P=.001) and 4.37 (95% confidence interval, 1.8-11.0; P=.001), respectively. CONCLUSION: Fetuses with a severe isolated left-sided congenital diaphragmatic hernia had a higher survival rate when treated in an experienced center in Germany with antenatal expectant management and frequent use of extracorporeal membrane oxygenation during the postnatal period than fetuses who were treated with fetoscopic endoluminal tracheal occlusion in 3 centers in Belgium, France, and Italy.

Effect of cannula insertion site during fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia on preterm prelabor rupture of membranes.

OBJECTIVE: To assess whether the cannula insertion site on the maternal abdomen during fetal endoscopic tracheal occlusion (FETO) for congenital diaphragmatic hernia (CDH) was associated with preterm prelabor rupture of membranes (PPROM) before balloon removal. METHODS: This was a multicenter retrospective study of consecutive pregnancies with isolated left- or right-sided CDH that underwent FETO in four centers between January 2009 and January 2021. The site for balloon insertion was categorized as above or below the umbilicus. One propensity score was analyzed in both groups to calculate an average treatment effect (ATE) by inverse probability of treatment weighting. Logistic regression and Cox proportional hazard regression including the ATE weights were performed to examine the effect size of entry point on the frequency and timing of PPROM before balloon removal. RESULTS: A total of 294 patients were included. The mean ± SD gestational age at PPROM was 33.45 ± 2.01 weeks and the mean rate of PPROM before balloon removal was 25.9% (76/294). Gestational age at FETO was later in the below-umbilicus group (mean ± SD, 29.47 ± 1.29 weeks vs 29.00 ± 1.25 weeks; P = 0.002) and the duration of FETO was longer in the above-umbilicus group (median, 14.49 min (interquartile range (IQR), 8.00-21.00 min) vs 11.00 min (IQR, 7.00-14.49 min); P = 0.002). After balancing for possible confounding factors, trocar entry point below the umbilicus did not increase the risk of PPROM before balloon removal (adjusted odds ratio, 1.56 (95% CI, 0.89-2.74); P = 0.120) and had no effect on the timing of PPROM before balloon removal (adjusted hazard ratio, 1.56 (95% CI, 0.95-2.55); P = 0.080). CONCLUSION: There was no evidence that uterine entry site for FETO was correlated with the risk of PPROM before balloon removal. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Congenital diaphragmatic hernia: quality improvement using a maximal lung protection strategy and early surgery-improved survival.

To evaluate the effectiveness of a novel protocol, adopted in our institution, as a quality improvement project for congenital diaphragmatic hernia (CDH). A maximal lung protection (MLP) protocol was implemented in 2019. This strategy included immediate use of high-frequency oscillatory ventilation (HFOV) after birth, during the stay at the Neonatal Intensive Care Unit (NICU), and during surgical repair. HFOV strategy included low distending pressures and higher frequencies (15 Hz) with subsequent lower tidal volumes. Surgical repair was performed early, within 24 h of birth, if possible. A retrospective study of all inborn neonates prenatally diagnosed with CDH and without major associated anomalies was performed at the NICU of Schneider Children's Medical Center of Israel between 2009 and 2022. Survival rates and pulmonary outcomes of neonates managed with MLP were compared to the historical standard care cohort. Thirty-three neonates were managed with the MLP protocol vs. 39 neonates that were not. Major adverse outcomes decreased including death rate from 46 to 18% (p = 0.012), extracorporeal membrane oxygenation from 39 to 0% (p < 0.001), and pneumothorax from 18 to 0% (p = 0.013). CONCLUSION:  MLP with early surgery significantly improved survival and additional adverse outcomes of neonates with CDH. Prospective randomized studies are necessary to confirm the findings of the current study. WHAT IS KNOWN: • Ventilator-induced lung injury was reported as the main cause of mortality in neonates with congenital diaphragmatic hernia (CDH). • Conventional ventilation is recommended by the European CDH consortium as the first-line ventilation modality; timing of surgery is controversial. WHAT IS NEW: • A maximal lung protection strategy based on 15-Hz high-frequency oscillatory ventilation with low distending pressures as initial modality and early surgery significantly reduced mortality and other outcomes.

Do FETO CDH survivors need the same follow-up program as non-FETO patients?

Congenital diaphragmatic hernia (CDH) survivors are at risk of developing significant chronic health conditions and disabilities. The main purpose of this study was to compare the outcomes of CDH infants at 2 years of age (2y) according to whether the infants had undergone fetoscopic tracheal occlusion (FETO) during the prenatal period and characterize the relationship between morbidity at 2y and perinatal characteristics. Retrospective cohort single center study. Eleven years of clinical follow-up data (from 2006 to 2017) were collected. Prenatal and neonatal factors as well as growth, respiratory, and neurological evaluations at 2y were analyzed. One hundred and fourteen CDH survivors were evaluated. Failure to thrive (FTT) was present in 24.6% of patients, gastroesophageal reflux disease (GERD) in 22.8%, 28.9% developed respiratory problems, and 22% had neurodevelopment disabilities. Prematurity and birth weight < 2500 g were related to FTT and respiratory morbidity. Time to reach full enteral nutrition and prenatal severity markers seemed to influence all outcomes, but FETO therapy itself only had an effect on respiratory morbidity. Some variables related to postnatal severity (ECMO, patch closure, days on mechanic ventilation, and vasodilator treatment) were associated with almost all outcomes.  Conclusion: CDH patients have specific morbidities at 2y, most of them related to lung hypoplasia severity. Only respiratory problems were related to FETO therapy itself. The implementation of a specific multidisciplinary follow-up program for CDH patients is essential to provide them the best standard of care, but, more severe patients, regardless of whether they received prenatal therapy, need a more intensive follow-up. What is Known: • Antenatal fetoscopic endoluminal tracheal occlusion (FETO) increases survival in more severe congenital diaphragmatic hernia patients. • Congenital diaphragmatic hernia survivors are at risk of developing significant chronic health conditions and disabilities. Very limited data are available about the follow-up in patients with congenital diaphragmatic hernia and FETO therapy. What is New: • CDH patients have specific morbidities at 2 years of age, most of them related to lung hypoplasia severity. • FETO patients present more respiratory problems at 2 years of age but they don't have an increased incidence of other morbidities. More severe patients, regardless of whether they received prenatal therapy, need a more intensive follow-up.

Characterization of Suboptimal Responses to Fetoscopic Endoluminal Tracheal Occlusion in Congenital Diaphragmatic Hernia.

INTRODUCTION: The aim of the study was to characterize the changes in fetal lung volume following fetoscopic endoluminal tracheal occlusion (FETO) that are associated with infant survival and need for extracorporeal membrane oxygenation (ECMO) in congenital diaphragmatic hernia (CDH). METHODS: Fetuses with CDH who underwent FETO at a single institution were included. CDH cases were reclassified by MRI metrics [observed-to-expected total lung volume (O/E TLV) and percent liver herniation]. The percent changes of MRI metrics after FETO were calculated. ROC-derived cutoffs of these changes were derived to predict infant survival to discharge. Regression analyses were done to determine the association between these cutoffs with infant survival and ECMO need, adjusted for site of CDH, gestational age at delivery, fetal sex, and CDH severity. RESULTS: Thirty CDH cases were included. ROC analysis demonstrated that post-FETO increases in O/E TLV had an area under the curve of 0.74 (p = 0.035) for the prediction of survival to hospital discharge; a cutoff of less than 10% was selected. Fetuses with a <10% post-FETO increase in O/E TLV had lower survival to hospital discharge [44.8% vs. 91.7%; p = 0.018] and higher ECMO use [61.1% vs. 16.7%; p = 0.026] compared to those with an O/E TLV increase ≥10%. Similar results were observed when the analyses were restricted to left-sided CDH cases. A post-FETO <10% increase in O/E TLV was independently associated with lower survival at hospital discharge (aOR: 0.073, 95% CI: 0.008-0.689; p = 0.022) and at 12 months of age (aOR: 0.091, 95% CI: 0.01-0.825; p = 0.036) as well as with higher ECMO use (aOR: 7.88, 95% CI: 1.31-47.04; p = 0.024). CONCLUSION: Fetuses with less than 10% increase in O/E TLV following the FETO procedure are at increased risk for requiring ECMO and for death in the postnatal period when adjusted for gestational age at delivery, CDH severity, and other confounders.

The metabolic and lipidomic profiling of the effects of tracheal occlusion in a rabbit model of congenital diaphragmatic hernia.

PURPOSE: Fetal tracheal occlusion (TO) reverses the pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH), but its mechanism of action remains poorly understood. 'Omic' readouts capture metabolic and lipid processing function, which aid in understanding CDH and TO metabolic mechanisms. METHODS: CDH was created in fetal rabbits at 23 days, TO at 28 days and lung collection at 31 days (Term ∼32 days). Lung-body weight ratio (LBWR) and mean terminal bronchiole density (MTBD) were determined. In a cohort, left and right lungs were collected, weighed, and samples homogenized, and extracts collected for non-targeted metabolomic and lipidomic profiling via LC-MS and LC-MS/MS, respectively. RESULTS: LBWR was significantly lower in CDH while CDH + TO was similar to controls (p = 0.003). MTBD was significantly higher in CDH fetuses and restored to control and sham levels in CDH + TO (p < 0.001). CDH and CDH + TO resulted in significant differences in metabolome and lipidome profiles compared to sham controls. A significant number of altered metabolites and lipids between the controls and CDH groups and the CDH and CDH + TO fetuses were identified. Significant changes in the ubiquinone and other terpenoid-quinone biosynthesis pathway and the tyrosine metabolism pathway were observed in CDH + TO. CONCLUSION: CDH + TO reverses pulmonary hypoplasia in the CDH rabbit, in association with a specific metabolic and lipid signature. A synergistic untargeted 'omics' approach provides a global signature for CDH and CDH + TO, highlighting cellular mechanisms among lipids and other metabolites, enabling comprehensive network analysis to identify critical metabolic drivers in disease pathology and recovery. TYPE OF STUDY: Basic Science, Prospective. LEVEL OF EVIDENCE: II.

Fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia: systematic review and meta-analysis.

OBJECTIVE: It is debated whether fetal endoscopic tracheal occlusion (FETO) is beneficial to fetuses with congenital diaphragmatic hernia (CDH) and whether FETO has different effects in moderate and severe CDH. We conducted a systematic review and meta-analysis including the latest evidence to assess the overall effects of FETO on clinical outcomes of CDH. METHODS: We searched PubMed, EMBASE, The Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database and Wanfang Database to retrieve eligible studies published before 8 September 2022. No language or study design restrictions were applied. Studies were included if CDH fetuses underwent FETO surgery and were compared with a cohort that underwent expectant management, with at least one outcome reported. The primary outcomes were mortality at 1, 6 and 12 months after birth, rates of pulmonary hypertension, use of extracorporeal membrane oxygenation (ECMO) and prematurity. Meta-analysis was conducted to obtain pooled odds ratios (ORs) and mean differences. The quality of included studies and pooled evidence was also assessed. RESULTS: A total of 1187 CDH fetuses from 20 studies were included in the quantitative synthesis. FETO significantly reduced 1-month (OR, 0.56 (95% CI, 0.34-0.93); P = 0.02, number needed to treat (NNT) = 7.67) and 6-month (OR, 0.34 (95% CI, 0.18-0.65); P = 0.0009, NNT = 5.26) CDH mortality (moderate/low quality of evidence). Subgroup analysis suggested that the effects of FETO on the rates of pulmonary hypertension and ECMO usage were significant in severe CDH (low/moderate quality of evidence) but not in moderate CDH (low/very low quality of evidence). FETO was also associated with an increased risk of preterm prelabor rupture of membranes before 37 weeks' gestation (OR, 4.94 (95% CI, 2.25-10.88); P < 0.0001, number needed to harm (NNH) = 3.13) and preterm birth before 37 weeks (OR, 5.24 (95% CI, 3.33-8.23); P < 0.00001, NNH = 2.79) (high/moderate quality of evidence). However, FETO was not associated with severe complications, such as preterm birth before 32 weeks, placental abruption or chorioamnionitis (very low/low quality of evidence). CONCLUSIONS: FETO is associated with a reduction in mortality, rate of pulmonary hypertension and ECMO usage in severe CDH, while it reduces only the risk of mortality in moderate CDH. Although FETO increases the risk of late prematurity, it does not result in extreme prematurity. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Plugging membranes after fetoscopy in congenital diaphragmatic hernia: early cost-effectiveness analysis.

OBJECTIVES: Fetal endoscopic tracheal occlusion (FETO) improves neonatal survival of fetuses with congenital diaphragmatic hernia (CDH). However, FETO also increases the risk of preterm prelabor rupture of membranes (PPROM) and preterm delivery (PTD), as fetal membrane defects after fetoscopy do not heal. To solve this issue, an advanced sealing plug for closing the membrane defect is being developed. Using early-stage health economic modeling, we aimed to estimate the potential value of this innovative plug in terms of costs and effects, and to determine the properties required for it to become cost-effective. METHODS: Early-stage health economic modeling was applied to the case of performing FETO in women with a singleton pregnancy whose fetus is diagnosed prenatally with CDH. We simulated a cohort of patients using a state-transition model over a 45-year time horizon. In our best-case-scenario analysis, we compared the current-care strategy with the perfect-plug strategy, which reduces the risk of PPROM and PTD by 100%, to determine the maximum quality-adjusted life years (QALYs) gained and costs saved. Using threshold analysis, we determined the minimum percentage reduction in the risk of PPROM and PTD required for the plug to be considered cost-effective. The impact of model parameters on outcome was investigated using a sensitivity analysis. RESULTS: Our model indicated that a perfect-plug strategy would yield on average an additional 1.94 QALYs at a cost decrease of €2554 per patient. These values were influenced strongly by the percentage of cases with early PTD (27-34 weeks). Threshold analysis showed that, for €500 per plug, the plug strategy needs a minimum percentage reduction of 1.83% in the risk of PPROM and PTD (i.e. reduction in the risk from 47.50% to 46.63% for PPROM and from 71.50% to 70.19% for PTD) to be cost-effective. CONCLUSIONS: Our model-based approach showed clear potential of the plug strategy when applied in the context of FETO for CDH fetuses, as only a minor reduction in the risk of PPROM and PTD is needed for the plug to be cost-effective. Its value is expected to be even higher when used in conditions associated with a higher rate of early PTD. Continued investment in research and development of the plug strategy appears to provide value for money. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Simulation training for urgent postnatal fetal tracheal balloon removal: Two learning methods.

OBJECTIVE: In fetuses with severe congenital diaphragmatic hernia, fetal endoluminal tracheal occlusion (FETO) with balloon increases survival and reduces morbidity. Balloon removal is often scheduled electively. In urgent cases, in-utero removal is impossible and removal immediately after delivery has to occur, posing risk of death from airway obstruction. Medical staff need training in urgent removal. Ideal training method is unclear; thus, we compared the performance of two groups trained by different methods. METHODS: 24 medical students were randomly assigned to two different learning methods for removal: Group 1 (in-person lecture) and Group 2 (online video). Both methods presented the same information: endoscopic instrument set-up, anatomical landmarks for intubation, and balloon removal. All participants were evaluated using the same instruments and high-fidelity simulator, comparing time for instrument set-up and simulate balloon removal (including removal attempts). RESULTS: Group 1 took significantly less time for instrument set-up compared to Group 2 [62 (30-92) secs vs 81 (57-108) secs; p < 0.01)]; no difference in time to intubate and locate the balloon [75 (50-173) secs vs 92 (32-232) secs; p 0.42], or number of attempts. CONCLUSION: There was no difference between video training and in-person training with regards to the time taken to locate the FETO balloon in the trachea and to simulate its removal.

Morbidity in children after fetoscopic endoluminal tracheal occlusion for severe congenital diaphragmatic hernia: Results from a multidisciplinary clinic.

BACKGROUND: Although fetoscopic endoluminal tracheal occlusion (FETO) was recently shown to improve survival in a multicenter, randomized trial of severe congenital diaphragmatic hernia (CDH), morbidity outcomes remain essentially unknown. The purpose of this study was to assess long-term outcomes in children with severe CDH who underwent FETO. METHODS: We conducted a prospective study of severe CDH patients undergoing FETO at an experienced North American center from 2015-2021 (NCT02710968). This group was compared to a cohort of non-FETO CDH patients with severe disease as defined by liver herniation, large defect size, and/or ECMO use. Clinical data were collected through a multidisciplinary CDH clinic. Statistics were performed with t-tests and Chi-squared analyses (p≤0.05). RESULTS: There were 18 FETO and 17 non-FETO patients. ECMO utilization was 56% in the FETO cohort. Despite significantly lower median observed/expected lung-to-head ratio (O/E LHR) in the FETO group, [FETO: 23% (IQR:18-25) vs. non-FETO: 36% (IQR: 28-41), p<0.001], there were comparable survival rates at discharge (FETO: 78% vs. non-FETO: 59%, p = 0.23) and at 5-years (FETO: 67% vs. non-FETO: 59%, p = 0.53) between the two cohorts. At a median follow up of 5.8 years, metrics of pulmonary hypertension, pulmonary morbidity, and gastroesophageal reflux disease improved among patients after FETO. However, most FETO patients remained on bronchodilators/inhaled corticosteroids (58%) and were feeding tube dependent (67%). CONCLUSIONS: These North American data show that prenatal tracheal occlusion, in conjunction with a long-term multidisciplinary CDH clinic, is associated with acceptable long-term survival and morbidity in children after FETO. LEVEL OF EVIDENCE: Level III.

Prenatal management of congenital diaphragmatic hernia.

Recently, two randomized controlled, prospective trials, the Tracheal Occlusion to Accelerate Lung Growth (TOTAL) trials, reported the outcomes on fetal endoluminal tracheal occlusion (FETO) for isolated left congenital diaphragmatic hernia (CDH). FETO significantly improved outcomes for severe hypoplasia. The effect in moderate cases, where the balloon was inserted later in pregnancy, did not reach significance. In a pooled analysis investigating the effect of the heterogeneity of the treatment effect by the time point of occlusion and severity, the difference may be explained by a difference in the duration of occlusion. Nevertheless, FETO carries a significant risk of preterm birth. The primary objective of this review is to provide an overview of the rationale for fetal intervention in CDH and the results of the randomized trials. The secondary objective is to discuss the technical aspects of FETO. Finally, recent developments of potential alternative fetal approaches will be highlighted.