Outcomes of congenital diaphragmatic hernia in the modern era of management

Increased Elastase and Matrix Metalloproteinase Levels in the Pulmonary Arteries of Infants With Congenital Diaphragmatic Hernia

BACKGROUND

Pulmonary vascular disease (PVD) complicated with pulmonary hypertension (PH) is a leading cause of mortality in congenital diaphragmatic hernia (CDH). Unfortunately, CDH patients are often resistant to PH therapy. Using the nitrogen CDH rat model, we previously demonstrated that CDH-associated PVD involves an induction of elastase and matrix metalloproteinase (MMP) activities, increased osteopontin and epidermal growth factor (EGF) levels, and enhanced smooth muscle cell (SMC) proliferation. Here, we aimed to determine whether the levels of the key members of this proteinase-induced pathway are also elevated in the pulmonary arteries (PAs) of CDH patients.

METHODS

Neutrophil elastase (NE), matrix metalloproteinase-2 (MMP-2), epidermal growth factor (EGF), tenascin-C, and osteopontin levels were assessed by immunohistochemistry in the PAs from the lungs of 11 CDH patients and 5 normal age-matched controls. Markers of proliferation (proliferating cell nuclear antigen (PCNA)) and apoptosis (cleaved (active) caspase-3) were also used.

RESULTS

While expressed by both control and CDH lungs, the levels of NE, MMP-2, EGF, as well as tenascin-C and osteopontin were significantly increased in the PAs from CDH patients. The percentage of PCNA-positive PA SMCs were also enhanced, while those positive for caspase-3 were slightly decreased.

CONCLUSIONS

These results suggest that increased elastase and MMPs, together with elevated tenascin-C and osteopontin levels in an EGF-rich environment may contribute to the PVD in CDH infants. The next step of this study is to expand our analysis to a larger cohort, and determine the potential of targeting this pathway for the treatment of CDH-associated PVD and PH.

TYPE OF STUDY

Therapeutic.

LEVEL OF EVIDENCE

LEVEL III.

Diaphragmatic Defects in Infants: Acute Management and Repair

Congenital diaphragmatic hernia (CDH) is a complex and highly variable disease process that should be treated at institutions with multidisciplinary teams designed for their care. Treatment in the neonatal period focuses on pulmonary hypoplasia, pulmonary hypertension, and cardiac dysfunction. Extracorporeal membrane oxygenation (ECMO) can be considered in patients refractory to medical management. Repair of CDH early during the ECMO course seems to improve mortality compared with other times for surgical intervention. The choice of surgical approach to CDH repair should consider the patient's physiologic status and the surgeon's familiarity with the operative approaches available, recognizing the pros/cons of each technique.

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.

Diagnosis, management and long term cardiovascular outcomes of phenotypic profiles in pulmonary hypertension associated with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a developmental defect of the diaphragm resulting in herniation of viscera into the chest. This condition is characterized by pulmonary hypoplasia, pulmonary hypertension (PH) and cardiac ventricular dysfunction. PH is a key component of the pathophysiology of CDH in neonates and contributes to morbidity and mortality. Traditionally, PH associated with CDH (CDH-PH) is thought to be secondary to increased pulmonary arterial resistance and vasoreactivity resulting from pulmonary hypoplasia. Additionally, there is increasing recognition of associated left ventricular hypoplasia, dysfunction and elevated end diastolic pressure resulting in pulmonary venous hypertension in infants with CDH. Thus, hemodynamic management of these infants is complex and cautious use of pulmonary vasodilators such as inhaled nitric oxide (iNO) is warranted. We aim to provide an overview of different phenotypic profiles of CDH associated PH and potential management options based on current evidence and pathophysiology.

Multicentre, randomised controlled trial of physiological-based cord clamping versus immediate cord clamping in infants with a congenital diaphragmatic hernia (PinC): statistical analysis plan

BACKGROUND

Infants born with congenital diaphragmatic hernia (CDH) are at high risk of respiratory insufficiency and pulmonary hypertension. Routine practice includes immediate clamping of the umbilical cord and endotracheal intubation. Experimental animal studies suggest that clamping the umbilical cord guided by physiological changes and after the lungs have been aerated, named physiological-based cord clamping (PBCC), could enhance the fetal-to-neonatal transition in CDH. We describe the statistical analysis plan for the clinical trial evaluating the effects of PBCC versus immediate cord clamping on pulmonary hypertension in infants with CDH (PinC trial).

DESIGN

The PinC trial is a multicentre, randomised controlled trial in infants with isolated left-sided CDH, born ≥ 35.0 weeks of gestation. The primary outcome is the incidence of pulmonary hypertension in the first 24 h after birth. Maternal outcomes include estimated maternal blood loss. Neonatal secondary outcomes include mortality before discharge, extracorporeal membrane oxygenation therapy, and number of days of mechanical ventilation. Infants are 1:1 randomised to either PBCC or immediate cord clamping using variable random permutated block sizes (4-8), stratified by treatment centre and estimated severity of pulmonary hypoplasia (i.e. mild/moderate/severe). At least 140 infants are needed to detect a relative reduction in pulmonary hypertension by one third, with 80% power and 0.05 significance level. A chi-square test will be used to evaluate the hypothesis that PBCC decreases the occurrence of pulmonary hypertension. This plan is written and submitted without knowledge of the collected data. The trial has been ethically approved.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04373902 (registered April 2020).

The etiology of congenital diaphragmatic hernia: the retinoid hypothesis 20 years later

Congenital diaphragmatic hernia (CDH) is a severe birth defect and a major cause of neonatal respiratory distress. Impacting ~2-3 in 10,000 births, CDH is associated with a high mortality rate, and long-term morbidity in survivors. Despite the significant impact of CDH, its etiology remains incompletely understood. In 2003, Greer et al. proposed the Retinoid Hypothesis, stating that the underlying cause of abnormal diaphragm development in CDH was related to altered retinoid signaling. In this review, we provide a comprehensive update to the Retinoid Hypothesis, discussing work published in support of this hypothesis from the past 20 years. This includes reviewing teratogenic and genetic models of CDH, lessons from the human genetics of CDH and epidemiological studies, as well as current gaps in the literature and important areas for future research. The Retinoid Hypothesis is one of the leading hypotheses to explain the etiology of CDH, as we continue to better understand the role of retinoid signaling in diaphragm development, we hope that this information can be used to improve CDH outcomes. IMPACT: This review provides a comprehensive update on the Retinoid Hypothesis, which links abnormal retinoic acid signaling to the etiology of congenital diaphragmatic hernia. The Retinoid Hypothesis was formulated in 2003. Twenty years later, we extensively review the literature in support of this hypothesis from both animal models and humans.

Place of birth and postnatal transfers in infants with congenital diaphragmatic hernia in England and Wales: a descriptive observational cohort study

OBJECTIVE

To describe clinical pathways for infants with congenital diaphragmatic hernia (CDH) and short-term outcomes.

DESIGN

Retrospective observational cohort study using the UK National Neonatal Research Database (NNRD).

PATIENTS

Babies with a diagnosis of CDH admitted to a neonatal unit in England and Wales between 2012 and 2020.

MAIN OUTCOME MEASURES

Clinical pathways defined by place of birth (with or without colocated neonatal and surgical facilities), transfers, clinical interventions, length of hospital stay and discharge outcome.

RESULTS

There were 1319 babies with a diagnosis of CDH cared for in four clinical pathways: born in maternity units with (1) colocated tertiary neonatal and surgical units ('neonatal surgical units'), 50% (660/1319); (2) designated tertiary neonatal unit and transfer to stand-alone surgical centre ('tertiary designated'), 25% (337/1319); (3) non-designated tertiary neonatal unit ('tertiary non-designated'), 7% (89/1319); or (4) non-tertiary unit ('non-tertiary'), 18% (233/1319)-the latter three needing postnatal transfers. Infant characteristics were similar for infants born in neonatal surgical and tertiary designated units. Excluding 149 infants with minimal data due to early transfer (median (IQR) 2.2 (0.4-4.5) days) to other settings, survival to neonatal discharge was 73% (851/1170), with a median (IQR) stay of 26 (16-44) days.

CONCLUSIONS

We found that half of the babies with CDH were born in hospitals that did not have on-site surgical services and required postnatal transfer. Similar characteristics between infants born in neonatal surgical units and tertiary designated units suggest that organisation rather than infant factors influence place of birth. Future work linking the NNRD to other datasets will enable comparisons between care pathways.

Rescuing lung development through embryonic inhibition of histone acetylation

A major barrier to the impact of genomic diagnosis in patients with congenital malformations is the lack of understanding regarding how sequence variants contribute to disease pathogenesis and whether this information could be used to generate patient-specific therapies. Congenital diaphragmatic hernia (CDH) is among the most common and severe of all structural malformations; however, its underlying mechanisms are unclear. We identified loss-of-function sequence variants in the epigenomic regulator gene SIN3A in two patients with complex CDH. Tissue-specific deletion of Sin3a in mice resulted in defects in diaphragm development, lung hypoplasia, and pulmonary hypertension, the cardinal features of CDH and major causes of CDH-associated mortality. Loss of SIN3A in the lung mesenchyme resulted in reduced cellular differentiation, impaired cell proliferation, and increased DNA damage. Treatment of embryonic Sin3a mutant mice with anacardic acid, an inhibitor of histone acetyltransferase, reduced DNA damage, increased cell proliferation and differentiation, improved lung and pulmonary vascular development, and reduced pulmonary hypertension. These findings demonstrate that restoring the balance of histone acetylation can improve lung development in the Sin3a mouse model of CDH.

Perfluorocarbons in Research and Clinical Practice: A Narrative Review

Perfluorocarbons (PFCs) are organic liquids derived from hydrocarbons in which some of the hydrogen atoms have been replaced by fluorine atoms. They are chemically and biologically inert substances with a good safety profile. They are stable at room temperature, easy to store, and immiscible in water. Perfluorocarbons have been studied in biomedical research since 1960 for their unique properties as oxygen carriers. In particular, PFCs have been used for liquid ventilation in unusual environments such as deep-sea diving and simulations of zero gravity, and more recently for drug delivery and diagnostic imaging. Additionally, when delivered as emulsions, PFCs have been used as red blood cell substitutes. This narrative review will discuss the multifaceted utilization of PFCs in therapeutics, diagnostics, and research. We will specifically emphasize the potential role of PFCs as red blood cell substitutes, as airway mechanotransducers during artificial placenta procedures, as a means to improve donor organ perfusion during the ex vivo assessment, and as an adjunct in cancer therapies because of their ability to reduce local tissue hypoxia.

Update on Management and Outcomes of Congenital Diaphragmatic Hernia

Infants with congenital diaphragmatic hernia (CDH) benefit from comprehensive multidisciplinary teams that have experience in caring for the unique and complex issues associated with CDH. Despite prenatal referral to specialized high-volume centers, advanced ventilation strategies and pulmonary hypertension management, and extracorporeal membrane oxygenation, mortality and morbidity remain high. These infants have unique and complex issues that begin in fetal and infant life, but persist through adulthood. Here we will review the literature and share our clinical care pathway for neonatal care and follow up. While many advances have occurred in the past few decades, our work is just beginning to continue to improve the mortality, but also importantly the morbidity of CDH.

Patent ductus arteriosus shunting direction and diameter predict inpatient outcomes in newborns with congenital diaphragmatic hernia

Objective

To evaluate whether the patent ductus arteriosus (PDA) can serve as a predictive factor for inpatient outcomes in congenital diaphragmatic hernia (CDH) patients.

Methods

A retrospective cohort study was conducted on 59 CDH patients at the Capital Institute of Pediatrics from January 2020 to August 2022. Echocardiography was performed at least three times: within 2-3 h after birth, pre-operatively, and post-operatively of CDH surgery. Based on the direction of the PDA shunt in the first echocardiogram, patients were classified into three groups: left-to-right shunting or closed PDA (L-R), bi-directional shunting, and right-to-left shunting (R-L).

Results

The mortality rate was 15.3% (9/59), with all non-survivors having R-L shunting and group mortality of 39.1% (9/23). The direction of the PDA shunt was significantly associated with the duration of ventilation and length of hospital stay (p < 0.05). Decreased PDA diameter or pre-operative shunting direction change towards L-R or bi-directional shunting were associated with higher survival rates, while increased PDA diameter or continuous R-L shunting were associated with higher mortality rates. Pre-operative PDA shunt direction, PDA size after birth and before surgery, gestational age of diagnosis, and shortening fraction before surgery were significantly correlated with patient outcomes. The direction of the preoperative PDA shunt was the most relevant factor among these relationships (p = 0.009, OR 20.6, CI 2.2∼196.1).

Conclusion

Our findings highlight the importance of monitoring changes in PDA shunt directionality and diameter in the early stage after birth, as these parameters may serve as valuable predictors of patient outcomes.

Quantitative Measures of Right Ventricular Size and Function by Echocardiogram Correlate with Cardiac Catheterization Hemodynamics in Congenital Diaphragmatic Hernia

OBJECTIVE

To evaluate associations between cardiac catheterization (cath) hemodynamics, quantitative measures of right ventricular (RV) function by echocardiogram, and survival in patients with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

This single-center retrospective cohort study enrolled patients with CDH who underwent index cath from 2003 to 2022. Tricuspid annular plane systolic excursion z score, RV fractional area change, RV free wall and global longitudinal strain, left ventricular (LV) eccentricity index, RV/LV ratio, and pulmonary artery acceleration time were measured from preprocedure echocardiograms. Associations between hemodynamic values, echocardiographic measures, and survival were evaluated by Spearman correlation and Wilcoxon rank sum test, respectively.

RESULTS

Fifty-three patients (68% left-sided, 74% liver herniation, 57% extracorporeal membrane oxygenation, 93% survival) underwent cath (39 during index hospitalization, 14 later) including device closure of a patent ductus arteriosus in 5. Most patients (n = 31, 58%) were on pulmonary hypertension treatment at cath, most commonly sildenafil (n = 24, 45%) and/or intravenous treprostinil (n = 16, 30%). Overall, hemodynamics were consistent with precapillary pulmonary hypertension. Pulmonary capillary wedge pressure was >15 mm Hg in 2 patients (4%). Lower fractional area change and worse ventricular strain were associated with higher pulmonary artery pressure while higher LV eccentricity index and higher RV/LV ratio were associated with both higher pulmonary artery pressure and higher pulmonary vascular resistance. Hemodynamics did not differ based on survival status.

CONCLUSIONS

Worse RV dilation and dysfunction by echocardiogram correlate with higher pulmonary artery pressure and pulmonary vascular resistance on cath in this CDH cohort. These measures may represent novel, noninvasive clinical trial targets in this population.

Congenital Heart Disease with Congenital Diaphragmatic Hernia: Surgical Decision Making and Outcomes

OBJECTIVE

To describe the types of congenital heart disease (CHD) in a congenital diaphragmatic hernia (CDH) cohort in a large volume center and evaluate surgical decision making and outcomes based on complexity of CHD and associated conditions.

STUDY DESIGN

A retrospective review of patients with CHD and CDH diagnosed by echocardiogram between 01/01/2005 and 07/31/2021. The cohort was divided into 2 groups based on survival at discharge.

RESULTS

Clinically important CHD was diagnosed in 19% (62/326) of CDH patients. There was 90% (18/20) survival in children undergoing surgery for both CHD and CDH as neonates, and 87.5 (22/24) in those undergoing repair initially for CDH alone. A genetic anomaly identified on clinical testing was noted in 16% with no significant association with survival. A higher frequency of other organ system anomalies was noted in nonsurvivors compared with survivors. Nonsurvivors were more likely to have unrepaired CDH (69% vs 0%, P < .001) and unrepaired CHD (88% vs 54%, P < .05), reflecting a decision not to offer surgery.

CONCLUSIONS

Survival was excellent in patients who underwent repair of both CHD and CDH. Patients with univentricular physiology have poor survival and this finding should be incorporated into pre and postnatal counseling about eligibility for surgery. In contrast, patients with other complex lesions including transposition of the great arteries have excellent outcomes and survival at 5 years follow-up at a large pediatric and cardiothoracic surgical center.

Enteric tube position on preoperative radiographs predicts clinical outcomes in neonatal congenital diaphragmatic hernia with and without prenatal diagnosis

OBJECTIVE

Congenital Diaphragmatic Hernia (CDH) is diagnosed prenatally in ~60% of cases. Prenatal measures typically guide management and prognostication. Simple postnatal prognosticators are needed when prenatal diagnosis is lacking. We hypothesized that preoperative orogastric tube (OGT) tip position relative to the contralateral diaphragm correlates with defect severity, resource utilization, and clinical outcomes regardless of diagnostic status.

STUDY DESIGN

150 neonates with left-posterolateral CDH were analyzed. Impact of intrathoracic and intraabdominal preoperative tip position on clinical outcomes was compared.

RESULTS

Ninety-nine neonates were prenatally diagnosed. Overall, intrathoracic position significantly correlated with larger diaphragmatic defects, advanced postnatal pulmonary support requirements (HFOV, pulmonary vasodilators, and ECMO), operative complexity, longer hospitalization, and poorer survival to discharge. These observations persisted when analyzing only cases lacking prenatal diagnosis.

CONCLUSIONS

Preoperative OGT tip position predicts defect severity, resource utilization, and outcomes in CDH. This observation enhances postnatal prognostication and care planning for neonates without a prenatal diagnosis.

Pathological findings in congenital diaphragmatic hernia on necropsy studies: A single-center case series

INTRODUCTION

Congenital diaphragmatic hernia (CDH) is associated with high mortality rates and significant pulmonary morbidities. The objective of this study was to delineate the histopathological features observed in necropsies of CDH patients and correlate these with their clinical manifestations.

METHODS

We retrospectively reviewed the postmortem findings and corresponding clinical characteristics in eight CDH cases from 2017 to July 2022.

RESULTS

The median survival time was 46 (8-624) hours. Autopsy reports showed that diffuse alveolar damage (congestion and hemorrhage) and hyaline membrane formation were the primary pathological lung changes observed. Notably, despite significant reduction in lung volume, the lung development appeared normal in 50% of the cases, while lobulated deformities were present in three (37.5%) cases. All patients displayed a large patent ductus arteriosus (PDA) and a patent foramen ovale, resulting in increased right ventricle (RV) volume, and myocardial fibers appeared slightly congested and swollen. The pulmonary vessels indicated thickening of the arterial media and adventitia. Lung hypoplasia and diffuse lung damage resulted in impaired gas exchange, while PDA and pulmonary hypertension led to RV failure, subsequent organ dysfunction and ultimately death.

CONCLUSIONS

Patients with CDH typically succumb to cardiopulmonary failure, a condition driven by a complex interplay of pathophysiological factors. This complexity accounts for the unpredictable response to currently available vasodilators and ventilation therapies.

Successful extracorporeal membrane oxygenation for postoperative cardiopulmonary failure in newborns with congenital diaphragmatic hernia: case reports and literature reviews

Introduction

Congenital diaphragmatic hernia (CDH) is a structural defect caused by inadequate fusion of the pleuroperitoneal membrane that forms the diaphragm, allowing peritoneal viscera to protrude into the pleural cavity. Up to 30% of newborns with CDH require extracorporeal membrane oxygenation (ECMO) support. As with all interventions, the risks and benefits of ECMO must be carefully considered in these patients. Cardiopulmonary function has been shown to worsen rather than improve after surgical CDH repair. Even after a detailed perioperative assessment, sudden cardiopulmonary failure after surgery is dangerous and requires timely and effective treatments.

Method

Three cases of cardiopulmonary failure after surgical CDH treatment in newborns have been reported. ECMO support was needed for these three patients and was successfully discontinued. We report our treatment experience.

Conclusion

ECMO is feasible for the treatment of postoperative cardiopulmonary failure in newborns with CDH.

In utero delivery of miRNA induces epigenetic alterations and corrects pulmonary pathology in congenital diaphragmatic hernia

Structural fetal diseases, such as congenital diaphragmatic hernia (CDH) can be diagnosed prenatally. Neonates with CDH are healthy in utero as gas exchange is managed by the placenta, but impaired lung function results in critical illness from the time a baby takes its first breath. MicroRNA (miR) 200b and its downstream targets in the TGF-β pathway are critically involved in lung branching morphogenesis. Here, we characterize the expression of miR200b and the TGF-β pathway at different gestational times using a rat model of CDH. Fetal rats with CDH are deficient in miR200b at gestational day 18. We demonstrate that novel polymeric nanoparticles loaded with miR200b, delivered in utero via vitelline vein injection to fetal rats with CDH results in changes in the TGF-β pathway as measured by qRT-PCR; these epigenetic changes improve lung size and lung morphology, and lead to favorable pulmonary vascular remodeling on histology. This is the first demonstration of in utero epigenetic therapy to improve lung growth and development in a pre-clinical model. With refinement, this technique could be applied to fetal cases of CDH or other forms of impaired lung development in a minimally invasive fashion.

Post-natal prognostic factors in CDH: experience of 11 years in a referral center in Brazil

OBJECTIVE

To describe post-natal risk factors associated with death in Newborns (NB) with Congenital Diaphragmatic Hernia (CDH) in a Brazilian reference center.

METHODS

In this retrospective cohort study, post-natal clinical factors of all NB diagnosed with CDH were reviewed in an 11-year period (2007‒2018). The primary outcome was death. Secondary outcomes included clinical features, prognostic indexes, type of mechanical ventilation, complications during hospitalization and surgical repair.

RESULTS

After applying the exclusion criteria, the authors analyzed 137 charts. Overall mortality was 59% (81/137), and the highest rates were observed for low-birth-weight NB (87%), syndromic phenotype (92%), and those with major malformations (100%). Prognostic indexes such as Apgar, SNAPPE-II and 24hOI (best oxygenation index in 24 hours) were all associated with poor evolution. In a multivariate analysis, only birth weight and 24hOI were statistically significant risk factors for mortality, with a reduction in mortality risk of 17.1% (OR = 0.829, 95% IC 0.72‒0.955, p = 0.009) for each additional 100g at birth and an increase by 26.5% (OR = 1.265, 95% IC 1.113‒1.436, p = 0.0003) for each unitary increase at the 24hOI.

CONCLUSION

Prognostic indexes are an important tool for predicting outcomes and improving resource allocation. Post-natal risk factors may be more suitable for settings where antenatal diagnosis is not universal. Classical risk factors, such as prematurity, low birth weight, higher need for supportive care, and poorer prognostic indexes were associated with mortality in our CDH population.

Fetal lung hypoxia and energetic cell failure in the nitrofen-induced congenital diaphragmatic hernia rat model

PURPOSE

Congenital diaphragmatic hernia (CDH) pathogenesis is poorly understood. We hypothesize that fetal CDH lungs are chronically hypoxic because of lung hypoplasia and tissue compression, affecting the cell bioenergetics as a possible explanation for abnormal lung development.

METHODS

To investigate this theory, we conducted a study using the rat nitrofen model of CDH. We evaluated the bioenergetics status using H1 Nuclear magnetic resonance and studied the expression of enzymes involved in energy production, the hypoxia-inducible factor 1α, and the glucose transporter 1.

RESULTS

The nitrofen-exposed lungs have increased levels of hypoxia-inducible factor 1α and the main fetal glucose transporter, more evident in the CDH lungs. We also found imbalanced AMP:ATP and ADP:ATP ratios, and a depleted energy cellular charge. Subsequent transcription levels and protein expression of the enzymes involved in bioenergetics confirm the attempt to prevent the energy collapse with the increase in lactate dehydrogenase C, pyruvate dehydrogenase kinase 1 and 2, adenosine monophosphate deaminase, AMP-activated protein kinase, calcium/calmodulin-dependent protein kinase 2, and liver kinase B1, while decreasing ATP synthase.

CONCLUSION

Our study suggests that changes in energy production could play a role in CDH pathogenesis. If confirmed in other animal models and humans, this could lead to the development of novel therapies targeting the mitochondria to improve outcomes.

Impact of a standardized management guideline for infants with CDH: A single-center experience

BACKGROUND

Infants with congenital diaphragmatic hernia (CDH) are at high risk of death, even despite extracorporeal membrane oxygenation (ECMO) support. In January 2012 we implemented a standardized clinical practice guideline (CPG) to manage infants with CDH. We hypothesized that infants with CDH managed with CPG had better clinical outcomes, less ECMO utilization, and increased survival to discharge.

METHODS

We conducted a retrospective pre-post study of infants with CDH admitted between January 2007 and July 2021 (n = 133). Patients were divided into Cohort 1, pre-CPG (January 2007 to December 2011, n = 54), and Cohort 2, post-CPG (January 2012 to July 2021, n = 79).

RESULTS

More patients in Cohort 1 were small for gestational age than in Cohort 2. No other patient demographics were different between cohorts. Cohort 2 had significantly lower ECMO utilization as compared to Cohort 1 (18% vs 50%, p<0.001). Cohort 2 had significantly higher survival to discharge compared to Cohort 1 (85% vs 57%, p<0.001). Survival for ECMO-treated patients in Cohort 2 was significantly higher than in Cohort 1 (71% vs 26%, p = 0.005). In Cohort 1, 70% of the non-survivors were repaired, of which 81% were repaired on ECMO. In Cohort 2, 8% of the non-survivors were repaired, none on ECMO. Only 3% in Cohort 2 were discharged with pulmonary hypertension medication.

CONCLUSIONS

A standardized CPG to manage patients with CDH decreased ECMO utilization and improved clinical outcomes including survival to discharge. Refinement of management strategies, implementation of new interventions, and meticulous care can improve outcomes in patients with CDH.

Long-term exercise and pulmonary function outcomes in a contemporary cohort of children with congenital diaphragmatic hernia

OBJECTIVE

Congenital diaphragmatic hernia (CDH) survivors are at risk for long-term exercise impairment and pulmonary morbidity, but the generalizability of prior reported cohorts are limited by reduced disease severity and older surgical eras. We assessed the mid-childhood exercise and pulmonary function outcomes in a contemporary cohort of CDH survivors.

STUDY DESIGN

In this retrospective cohort study, we identified 36 consecutive pediatric CDH survivors who underwent cardiopulmonary exercise testing (CPET) and spirometry from 2014 to 2021. Inferential statistics compared survivors with age-, sex-, and size-matched healthy controls; univariate analyses identified factors associated with abnormal testing.

RESULTS

Maximal effort CPET and resting spirometry were completed by 27/36 (75%) and 31/36 (86%) subjects, respectively (median age: 8.1 years [interquartile range: 7.5, 10]; 16 females [44%]). Abnormal CPET (percent predicted [pp] peak VO₂  < 80%) was more common in the CDH cohort (12 vs. 1, p < 0.001) and associated with longer neonatal intensive care unit (NICU) stay (p = 0.02) and oxygen therapy at discharge (p = 0.03). Exercise impairment was mild (pp peak VO₂ 70%-80%), moderate (60%-70%), and severe (<60%) in 6, 4, and 2 survivors, respectively. Abnormal spirometry was more common in the CDH cohort (21 vs. 3, p < 0.001; obstructive [n = 15], restrictive [n = 6]) and associated with decreased gestational age (p = 0.046), longer mechanical ventilation in the NICU (p = 0.02), and orthopedic abnormalities (p = 0.03).

CONCLUSION(S)

Exercise capacity was normal or mildly impaired in most CDH survivors, however, approximately two-thirds demonstrated abnormal spirometry. Impaired exercise capacity and lung function were associated with severity of lung disease postnatally. These data support cardiopulmonary follow-up throughout childhood.

Variability for Age at Successful Extubation in Infants with Congenital Diaphragmatic Hernia

OBJECTIVE

The objective of this study was to characterize clinical factors associated with successful extubation in infants with congenital diaphragmatic hernia.

STUDY DESIGN

Using the Children's Hospitals Neonatal Database, we identified infants with congenital diaphragmatic hernia from 2017 to 2020 at 32 centers. The main outcome was age in days at the time of successful extubation, defined as the patient remaining extubated for 7 consecutive days. Unadjusted Kaplan-Meier and multivariable Cox proportional hazards ratio equations were used to estimate associations between clinical factors and the main outcome. Observations occurred through 180 days after birth.

RESULTS

There were 840 eligible neonates with a median gestational age of 38 weeks and birth weight of 3.0 kg. Among survivors (n = 693), the median age at successful extubation was 15 days (interquartile range [IQR]: 8-29 days, 95th percentile: 71 days). For nonsurvivors (n = 147), the median age at death was 21 days (IQR: 11-39 days, 95th percentile: 110 days). Center (adjusted hazards ratio: 0.22-15, P < .01), low birth weight, intrathoracic liver position, congenital heart disease, lower 5-minute Apgar score, lower pH upon admission to Children's Hospitals Neonatal Database center, and use of extracorporeal support were independently associated with older age at successful extubation. Tracheostomy was associated with multiple failed extubations.

CONCLUSION

Our findings suggest that infants who have not successfully extubated by about 3 months of age may be candidates for tracheostomy with chronic mechanical ventilation or palliation. The variability of timing of successful extubation among our centers supports the development of practice guidelines after validating clinical criteria.

School age educational outcomes of infants born with congenital diaphragmatic hernia

BACKGROUND

To compare academic proficiency among children with congenital diaphragmatic hernia (CDH) versus controls and identify predictors of academic performance among children with CDH.

METHODS

Infants born with CDH in Arkansas, 2000-2005, were identified from the Arkansas Reproductive Health Monitoring System. For each case, two controls were selected from birth certificate data and matched for hospital and month of birth, sex, and race/ethnicity. Data on re-hospitalization within the first 5 years and payer data were collected from the Arkansas Hospital Inpatient Discharge database. Surviving cases and controls were linked to the Arkansas Department of Education database. Primary outcomes were odds of proficiency on fourth grade literacy and mathematics achievement tests. Multivariable logistic regression models evaluated the association between study characteristics and academic proficiency.

RESULTS

The final study cohort included 25 surviving CDH cases and 31 controls who were linked to their education data. After adjusting for differences in characteristics (5-min Apgar score and associated congenital anomalies) between cases and controls, there were no statistically significant differences in literacy (72% vs. 84%, p = .93) or mathematics (64% vs. 81%, p = .98) test proficiency between the two groups. In multivariable analyses, among CDH cases, oxygen at discharge and Medicaid payer/longer hospital stay were associated with worse fourth grade literacy and mathematics proficiency, respectively.

CONCLUSIONS

Oxygen at discharge, Medicaid payer, and longer hospital stay were associated with lower academic performance among CDH cases.

Case report: High-dose epoprostenol therapy in pediatric patients with pulmonary hypertension and developmental lung disease

Pulmonary hypertension (PH) with developmental lung disease is a life-threatening disease and accounts for 10%-12% of pediatric PH patients. Administration of specific pulmonary vasodilators to pediatric PH patients has brought about improvement of their long-term prognosis. Intravenous epoprostenol therapy is a gold standard therapy for severe idiopathic pulmonary arterial hypertension (IPAH), but there are few reports demonstrating the efficacy of epoprostenol for pediatric PH patients with developmental lung disease, especially when treating with high doses of epoprostenol. Two cases of pediatric PH patients with alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) and congenital diaphragmatic hernia (CDH) with bronchopulmonary dysplasia (BPD), respectively, treated with epoprostenol above 100 ng/kg/min are presented. In these two cases, severe PH was improved significantly by an aggressive increase of the epoprostenol infusion rate with administration of oral pulmonary vasodilators and appropriate respiratory management, without any significant adverse effects. High-dose epoprostenol therapy may be one of the therapeutic options in pediatric PH patients with developmental lung disease.

Being small for gestational age is not an independent risk factor for mortality in neonates with congenital diaphragmatic hernia: a multicenter study

BACKGROUND

Congenital diaphragmatic hernia (CDH) accounts for 8% of all major congenital anomalies. Neonates who are small for gestational age (SGA) generally have a poorer prognosis. We sought to identify risk factors and variables associated with outcomes in neonates with CDH who are SGA in comparison to neonates who are appropriate for gestational age (AGA).

METHODS

We used the multicenter Diaphragmatic Hernia Research & Exploration Advancing Molecular Science (DHREAMS) study to include neonates enrolled from 2005 to 2019. Chi-squared or Fisher's exact tests were used to compare categorical variables and t tests or Wilcoxon rank sum for continuous variables. Cox model analyzed time to event outcomes and logistic regression analyzed binary outcomes.

RESULTS

589 neonates were examined. Ninety were SGA (15.3%). SGA patients were more likely to be female (p = 0.003), have a left sided CDH (p = 0.05), have additional congenital anomalies and be diagnosed with a genetic syndrome (p < 0.001). On initial single-variable analysis, SGA correlated with higher frequency of death prior to discharge (p < 0.001) and supplemental oxygen requirement at 28 days (p = 0.005). Twice as many SGA patients died before repair (12.2% vs 6.4%, p = 0.04). Using unadjusted Cox model, the risk of death prior to discharge among SGA patients was 1.57 times the risk for AGA patients (p = 0.029). There was no correlation between SGA and need for ECMO, pulmonary hypertensive medication at discharge or oxygen at discharge. After adjusting for confounding variables, SGA no longer correlated with mortality prior to discharge or incidence of unrepaired defects but remained significant for oxygen requirement at 28 days (p = 0.03).

CONCLUSION

Infants with CDH who are SGA have worse survival and poorer lung function than AGA infants. However, the outcome of SGA neonates is impacted by other factors including gestational age, genetic syndromes, and particularly congenital anomalies that contribute heavily to their poorer prognosis.

Extracorporeal Membrane Oxygenation (ECMO) and its complications in newborns with congenital diaphragmatic hernia

BACKGROUND

Extracorporeal Membrane Oxygenation (ECMO) is offered to patients with congenital diaphragmatic hernia (CDH) who are in severe respiratory and cardiac failure. We aim to describe the types of complications among these patients and their impact on survival.

METHODS

A single-center, retrospective review of CDH patients cannulated onto ECMO between January 2005 and November 2020 was conducted. ECMO complications, as categorized by the Extracorporeal Life Support Organization (ELSO), were correlated with survival status. Descriptive statistics were used to compare observed complications between survivors and non-survivors.

RESULTS

In our cohort of CDH neonates, 21% (54/258) were supported with ECMO, of whom, 61% (33/54) survived. Survivors and non-survivors were similar in baseline characteristics except for birthweight z-score (p = 0.043). Seventy percent of CDH neonates experienced complications during their ECMO run, with the most common categories being metabolic (48.1%) and mechanical (38.9%), followed by hemorrhage (22.2%), neurological (18.5%), renal (11.1%), pulmonary (7.4%), and cardiovascular (7.4%). The median number of complications per patient was higher in the non-survivor group  (2 (IQR: 1-4) vs 1 (IQR: 0-2), p = 0.043). In addition, mechanical (57.1% vs 27.3%, p = 0.045) and renal (28.6% vs 0%, p = 0.002) complications were more common among non-survivors compared to survivors.

CONCLUSION

Complications occur frequently among ECMO-treated newborns with CDH, some of which have serious long-term consequences. Survivors had higher birth weight z-scores, shorter ECMO runs, and fewer complications per patient. Mechanical and renal complications were independently associated with mortality, emphasizing the utility of more focused strategies to target fluid balance and renal protection and to prevent circuit and cannula complications.

Perinatal Prognostic Factors for Congenital Diaphragmatic Hernia: A Korean Single-Center Study

Purpose: This study aimed to identify prognostic factors based on treatment outcomes for congenital diaphragmatic hernia (CDH) at a single-center and to identify factors that may improve these outcomes.Methods: Thirty-five neonates diagnosed with CDH between January 2011 and December 2021 were retrospectively analyzed. Pre- and postnatal factors were correlated and analyzed with postnatal clinical outcomes to determine the prognostic factors. Highest oxygenation index (OI) within 24 hours of birth was also calculated. Treatment strategy and outcome analysis of published literatures were also performed.Results: Overall survival rate of this cohort was 60%. Four patients were unable to undergo anesthesia and/or surgery. Three patients who commenced extracorporeal membrane oxygenation (ECMO) post-surgery were non-survivors. Compared to the survivor group, the non-survivor group had a significantly higher occurrence of pneumothorax on the first day, need for high-frequency ventilator and inhaled nitric oxide use, and high OI within the first 24 hours. The non-survivor group showed an early trend towards the surgery timing and a greater number of patch closures. Area under the receiver operating characteristic curve was 0.878 with a sensitivity of 76.2% and specificity of 92.9% at an OI cutoff value of 7.75.Conclusion: OI within 24 hours is a valuable predictor of survival. It is expected that the application of ECMO based on OI monitoring may help improve the opportunity for surgical repair, as well as the prognosis of CDH patients.

Early Abnormalities in Gas Exchange in Infants with Congenital Diaphragmatic Hernia

OBJECTIVE

To determine how blood gas exchange is altered during the transition in the first hour of life in infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

This was a prospective observational cohort study evaluating arterial blood gas (ABG) samples and ventilator support in 34 infants with CDH in the first hour of life. Infants were stratified into mild, moderate, and severe CDH. The first ABG was compared with the umbilical cord ABGs and response to intervention evaluated on subsequent ABGs among infants with different CDH severities.

RESULTS

Infants were intubated at a median of 120 seconds (range 50-240 seconds) and ABGs obtained at a median of 6 minutes (IQR 4, 8 minutes), 16 minutes (IQR 13.5, 22.5 minutes), and 60 minutes (IQR 56, 64 minutes). Compared with the cord ABG, first ABG mean partial pressure of carbon dioxide (PaCO₂) increased from 49.8 mm Hg to 82.1 mm Hg, mean base deficit decreased from -2.2 to -7.3, and mean pH from 7.298 to 7.060. With ventilator adjustments, second mean PaCO₂ decreased to 76.7 mm Hg and third mean PaCO₂ 48.5 mm Hg. When stratified, with all CDH severities PaCO₂ increased abruptly, remained elevated in moderate and severe CDH, and improved in all severities by 60 minutes after delivery.

CONCLUSIONS

Gas exchange is markedly altered in the first hour of life in infants with CDH with abrupt onset of acidemia and a mixed respiratory and metabolic acidosis. Early implementation of adequate cardiopulmonary support may contribute to more timely stabilization of gas exchange.

Long-term outcomes of congenital diaphragmatic hernia: A single institution experience

BACKGROUND/PURPOSE

As survival rates for patients with congenital diaphragmatic hernia (CDH) increase, long-term sequelae become increasingly prevalent. We present the outcomes of patients who underwent CDH repair at our institution and discuss standardization of follow-up care in our long-term multidisciplinary follow-up clinic.

METHODS

A retrospective review of patients followed in multidisciplinary clinic after CDH repair at our institution from January 1, 2005 to December 1, 2020.

RESULTS

A total of 193 patients met inclusion criteria, 73 females (37.8%) and 120 males (62.2%). Left-sided defects were most common (75.7%), followed by right-sided defects (20.7%). Median age at repair was 4 days (IQR 3-6) and 59.6% of all defects required patch repair. Median length of stay was 29 days (IQR 16.8-50.0). Median length of follow up was 49 months (IQR 17.8-95.3) with 25 patients followed for more than 12 years. Long-term outcomes included gastroesophageal reflux disease (42.0%), diaphragmatic hernia recurrence (10.9%), asthma (23.6%), neurodevelopmental delay (28.6%), attention deficit hyperactivity disorder (7.3%), autism (1.6%), chest wall deformity (15.5%), scoliosis (11.4%), and inguinal hernia (6.7%).

CONCLUSION

As survival of patients with CDH improves, long-term care must be continuously studied and fine-tuned to ensure appropriate surveillance and optimization of long-term outcomes.

Physiological-based cord clamping versus immediate cord clamping for infants born with a congenital diaphragmatic hernia (PinC): study protocol for a multicentre, randomised controlled trial

INTRODUCTION

Pulmonary hypertension is a major determinant of postnatal survival in infants with a congenital diaphragmatic hernia (CDH). The current care during the perinatal stabilisation period in these infants might contribute to the development of pulmonary hypertension after birth-in particular umbilical cord clamping before lung aeration. An ovine model of diaphragmatic hernia demonstrated that cord clamping after lung aeration, called physiological-based cord clamping (PBCC), avoided the initial high pressures in the lung vasculature while maintaining adequate blood flow, thereby avoiding vascular remodelling and aggravation of pulmonary hypertension. We aim to investigate if the implementation of PBCC in the perinatal stabilisation period of infants born with a CDH could reduce the incidence of pulmonary hypertension in the first 24 hours after birth.

METHODS AND ANALYSIS

We will perform a multicentre, randomised controlled trial in infants with an isolated left-sided CDH, born at ≥35.0 weeks. Before birth, infants will be randomised to either PBCC or immediate cord clamping, stratified by treatment centre and severity of pulmonary hypoplasia on antenatal ultrasound. PBCC will be performed using a purpose-built resuscitation trolley. Cord clamping will be performed when the infant is considered respiratory stable, defined as a heart rate >100 bpm, preductal oxygen saturation >85%, while using a fraction of inspired oxygen of <0.5. The primary outcome is pulmonary hypertension diagnosed in the first 24 hours after birth, based on clinical and echocardiographic parameters. Secondary outcomes include neonatal as well as maternal outcomes.

ETHICS AND DISSEMINATION

Central ethical approval was obtained from the Medical Ethical Committee of the Erasmus MC, Rotterdam, The Netherlands (METC 2019-0414). Local ethical approval will be obtained by submitting the protocol to the regulatory bodies and local institutional review boards.

TRIAL REGISTRATION NUMBER

NCT04373902.

Risk factors for hospitalisation in Welsh infants with a congenital anomaly

OBJECTIVES

To investigate risk factor associated with hospitalisation of infants with a congenital anomaly in Wales, UK.

DESIGN

A population-based cohort study.

SETTING

Data from the Welsh Congenital Anomaly Register and Information Service linked to the Patient Episode Database for Wales and livebirths and deaths from the Office for National Statistics.

PATIENTS

All livebirths between 1999 and 2015 with a diagnosis of a congenital anomaly, which was defined as a structural, metabolic, endocrine or genetic defect, as well as rare diseases of hereditary origin.

MAIN OUTCOME MEASURES

Adjusted OR (aOR) associated with 1 or 2+ hospital admissions in infancy versus no admissions were estimated for sociodemographic, maternal and infant factors using multinomial logistic regression for the subgroups of all, isolated, multiple and cardiovascular anomalies.

RESULTS

25 523 infants affected by congenital anomalies experienced a total of 50 705 admissions in infancy. Risk factors for ≥2 admissions were younger maternal age ≤24 years (aOR: 1.17; 95% CI 1.06 to 1.30), maternal smoking (aOR: 1.20; 1.10 to 1.31), preterm birth (aOR: 2.52; 2.25 to 2.83) and moderately severe congenital heart defects (aOR: 6.25; 4.47 to 8.74). Girls had an overall decreased risk of 2+ admissions (aOR: 0.84; 0.78 to 0.91). Preterm birth was a significant risk factor for admissions in all anomaly subgroups but the effect of the other characteristics varied according to anomaly subgroup.

CONCLUSIONS

Over two-thirds of infants with an anomaly are admitted to hospital during infancy. Our findings identified sociodemographic and clinical characteristics contributing to an increased risk of hospitalisation of infants with congenital anomalies.

Outcomes for infants with congenital diaphragmatic hernia: A single campus review with low extracorporeal membrane oxygenation utilisation

AIM

To report the outcome for infants with congenital diaphragmatic hernia (CDH) and identify clinical factors affecting outcome from a tertiary perinatal surgical campus where extracorporeal membrane oxygenation (ECMO) is available however rarely utilised.

METHODS

A retrospective cohort study of infants with CDH born in a co-located perinatal neonatal intensive care unit (NICU) or retrieved into and managed at a surgical NICU: 2003-2018.

RESULTS

One hundred and fifty-nine infants with CDH were identified. One hundred and twenty were born in the co-located hospital and 39 retrieved from outlying hospitals. Survival of all patients with CDH was 74.8%; The survival for all isolated left CDH was 89% and the survival of post-surgery was 93%. Two patients went onto ECMO and both died. Associated major congenital anomalies were seen in 13.2%. Low birthweight (< 2500 g), 5-min Apgar <5, antenatal diagnosis, right-sided diaphragmatic hernia, herniation of the liver, associated major congenital anomalies, high oxygenation index (>25) on day 1, inotrope use, inhaled nitric oxide and need for high-frequency ventilation were associated with increased mortality on univariate analysis. Neurodevelopmental follow-up was commenced in 2013. Forty-three infants were discharged and developmental data were available for 36 at 4 months (83%) and 32 at 1 year (73%). Outcomes revealed normal motor scores and expressive language with mild delay in the receptive language at 1 year.

CONCLUSION

Despite the low use of ECMO, our centre's results reveal excellent survival and neurodevelopmental outcomes consistent with or better than international data.

In-Hospital Morbidities for Neonates with Congenital Diaphragmatic Hernia: The Impact of Defect Size and Laterality

OBJECTIVE

To determine in-hospital morbidities for neonates with right-sided congenital diaphragmatic hernia (R-CDH) compared with those with left-sided defects (L-CDH) and to examine the differential effect of laterality and defect size on morbidities.

STUDY DESIGN

This retrospective, multicenter, cohort study from the international Congenital Diaphragmatic Hernia Study Group registry collected data from neonates with CDH surviving until hospital discharge from 90 neonatal intensive care units between January 1, 2007, and July 31, 2020. Major pulmonary, cardiac, neurologic, and gastrointestinal morbidities were compared between neonates with L-CDH and R-CDH, adjusted for prenatal and postnatal factors using logistic regression.

RESULTS

Of 4123 survivors with CDH, those with R-CDH (n = 598 [15%]) compared with those with L-CDH (n = 3525 [85%]) had an increased odds of pulmonary (1.7; 95% CI, 1.4-2.2, P < .0001), cardiac (1.4; 95% CI, 1.1-1.8; P = .01), gastrointestinal (1.3; 95% CI, 1.1-1.6; P = .01), and multiple (1.6; 95% CI, 1.2-2.0; P < .001) in-hospital morbidities, with a greater likelihood of morbidity with increasing defect size. There was no difference in neurologic morbidities between the groups.

CONCLUSIONS

Neonates with R-CDH and a larger defect size are at an increased risk for in-hospital morbidities. Counseling and clinical strategies should incorporate knowledge of these risks, and approach to neonatal R-CDH should be distinct from current practices targeted to L-CDH.

Pulmonary Hypertension in Children across Africa: The Silent Threat

Pulmonary hypertension (PH) is a complex puzzle in Africa, especially among children who present with a cocktail of issues including recurrent pulmonary infections, unoperated congenital heart disease, and advanced rheumatic heart disease. Sickle cell anemia and neonatal complications of transiting from fetal circulation also contribute to the burden of pulmonary hypertension. Mortality from pulmonary arterial hypertension (PAH) remains high in Africa (18-21%), claiming sufferers in the first 6 months after diagnosis. Unfortunately, PH remains underreported in sub-Saharan Africa since many centers lack the capacity to diagnose and confirm it by the recommended gold standard, right heart catheterization. The unresolved burden of unoperated congenital heart lesions and rheumatic heart disease, among other preventable causes, stand out as major causes of PH in African children. This paper highlights pediatric PAH as a result of major gaps in care and illustrates the need for its prevention as well as for the promotion of research into the most important drivers, to prevent premature mortality in the continent.

Magnetic Resonance Imaging Assessment of Pulmonary Vascularity in Infants with Congenital Diaphragmatic Hernia: A Novel Tool for Direct Assessment of Severity of Pulmonary Hypertension and Hypoplasia

OBJECTIVES

To assess the feasibility of magnetic resonance imaging (MRI) for postnatal assessment of pulmonary vascularity in infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

Infants with prenatally diagnosed CDH (n = 24) received postnatal pulmonary MRI. Infants with nonpulmonary birth defects served as controls (n = 5). Semiautomatic segmentation was performed to obtain total vascular volume using time of flight images to assess vascularity.

RESULTS

Average vascular density (vascular volume/lung volume) in control infants was 0.23 ± 0.06 mm³/mm³ compared with 0.18 ± 0.06 mm³/mm³ in infants with CDH is (P = .09). When stratified further based on CDH severity, the difference between control infants and moderate CDH group was statistically significant. (0.23 mm³/mm³ vs 0.15 mm³/mm³, P = .01). Ipsilateral vascular density on MRI in infants with CDH significantly correlated with the prenatal pulmonary hypertensive index (P = .0004, Spearman R = +0.87) and with number of days on mechanical ventilation (P = .04, Spearman R = -0.44), total days on inhaled nitric oxide (P = .02, Spearman R = -0.47), use of epoprostenol for acute pulmonary hypertension (PH) (0.14 mm³/mm³ vs 0.20 mm³/mm³, P = .005), and use of sildenafil for chronic PH (0.15 mm³/mm³ vs 0.19 mm³/mm³, P = .03).

CONCLUSIONS

Our results suggest that postnatal pulmonary vascularity assessed by MRI strongly correlates with prenatal and postnatal markers of PH severity and that pulmonary vascularity may serve as a direct measure of pulmonary vascular hypoplasia in infants with CDH.

Decreased neonatal morbidity in 'stomach-down' left congenital diaphragmatic hernia: implications of prenatal ultrasound diagnosis for counseling and postnatal management

OBJECTIVE

To evaluate the influence of stomach position on postnatal outcome in cases of left congenital diaphragmatic hernia (CDH) without liver herniation, diagnosed and characterized on prenatal ultrasound (US), by comparing those with ('stomach-up' CDH) to those without ('stomach-down' CDH) intrathoracic stomach herniation.

METHODS

Infants with left CDH who underwent prenatal US and postnatal repair at our institution between January 2008 and March 2017 were eligible for inclusion in this retrospective study. Detailed prenatal US examinations, fetal magnetic resonance imaging (MRI) studies, operative reports and medical records of infants enrolled in the pulmonary hypoplasia program at our institution were reviewed. Cases with liver herniation and those with an additional anomaly were excluded. Cases in which bowel loops were identified within the fetal chest on US while the stomach was intra-abdominal were categorized as having stomach-down CDH. Cases in which bowel loops and the stomach were visualized within the fetal chest on US were categorized as having stomach-up CDH. Prenatal imaging findings and postnatal outcomes were compared between the two groups.

RESULTS

In total, 152 patients with left CDH were initially eligible for inclusion. Seventy-eight patients had surgically confirmed liver herniation and were excluded. Of the 74 included CDH cases without liver herniation, 28 (37.8%) had stomach-down CDH and 46 (62.2%) had stomach-up CDH. Of the 28 stomach-down CDH cases, 10 (35.7%) were referred for a suspected lung lesion. Sixty-eight (91.9%) cases had postnatal outcome data available for analysis. There was no significant difference in median observed-to-expected (o/e) lung-area-to-head-circumference ratio (LHR) between cases with stomach-down CDH and those with stomach-up CDH (41.5% vs 38.4%; P = 0.41). Furthermore, there was no difference in median MRI o/e total lung volume (TLV) between the two groups (49.5% vs 44.0%; P = 0.22). Compared with stomach-up CDH patients, stomach-down CDH patients demonstrated lower median duration of intubation (18 days vs 9.5 days; P < 0.01), median duration of extracorporeal membrane oxygenation (495 h vs 223.5 h; P < 0.05), rate of supplemental oxygen requirement at 30 days of age (20/42 (47.6%) vs 3/26 (11.5%); P < 0.01) and rate of pulmonary hypertension at initial postnatal echocardiography (28/42 (66.7%) vs 9/26 (34.6%); P = 0.01). No neonatal death occurred in stomach-down CDH patients and one neonatal death was seen in a patient with intrathoracic stomach herniation.

CONCLUSIONS

In infants with left CDH without liver herniation, despite similar o/e-LHR and o/e-TLV, those with stomach-down CDH have decreased neonatal morbidity compared to those with stomach herniation. Progressive or variable physiological distension of the stomach over the course of gestation may explain these findings. Stomach-down left CDH is mistaken for a lung mass in a substantial proportion of cases. Accurate prenatal US characterization of CDH is crucial for appropriate prenatal counseling and patient management. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Rare and de novo variants in 827 congenital diaphragmatic hernia probands implicate LONP1 as candidate risk gene

Congenital diaphragmatic hernia (CDH) is a severe congenital anomaly that is often accompanied by other anomalies. Although the role of genetics in the pathogenesis of CDH has been established, only a small number of disease-associated genes have been identified. To further investigate the genetics of CDH, we analyzed de novo coding variants in 827 proband-parent trios and confirmed an overall significant enrichment of damaging de novo variants, especially in constrained genes. We identified LONP1 (lon peptidase 1, mitochondrial) and ALYREF (Aly/REF export factor) as candidate CDH-associated genes on the basis of de novo variants at a false discovery rate below 0.05. We also performed ultra-rare variant association analyses in 748 affected individuals and 11,220 ancestry-matched population control individuals and identified LONP1 as a risk gene contributing to CDH through both de novo and ultra-rare inherited largely heterozygous variants clustered in the core of the domains and segregating with CDH in affected familial individuals. Approximately 3% of our CDH cohort who are heterozygous with ultra-rare predicted damaging variants in LONP1 have a range of clinical phenotypes, including other anomalies in some individuals and higher mortality and requirement for extracorporeal membrane oxygenation. Mice with lung epithelium-specific deletion of Lonp1 die immediately after birth, most likely because of the observed severe reduction of lung growth, a known contributor to the high mortality in humans. Our findings of both de novo and inherited rare variants in the same gene may have implications in the design and analysis for other genetic studies of congenital anomalies.

Congenital diaphragmatic hernia: a single-centre experience at Kepler University Hospital Linz

Congenital diaphragmatic hernia (CDH) is found in about 1 of 3000 live births and is often complicated by pulmonary hypoplasia and alteration of the pulmonary arterial wall with resulting pulmonary hypertension. Since 2005, with the fusion of the children’s hospital and the maternity clinic of the Kepler University Hospital Linz, affected neonates have been treated according to a standard protocol at our perinatal centre. Some prenatally measured parameters have been used to predict mortality, e.g., observed-to-expected lung-to-head ratio or lung volume measurements by nuclear magnetic resonance imaging. We performed a retrospective chart review of 67 new-borns with CDH treated at our institution to detect any predictors of hospital mortality from parameters routinely collected within the first 24 h of life. The term “liver up” was identified as a predictor of hospital mortality; OR 9.2 (95% CI 1.9–51.1, p = 0.002, sensitivity 79%, specificity 71%). In addition, the need for application of high-frequency oscillatory ventilation during the first 24 h was associated with mortality; OR 44.4 (95% CI 6.3–412.1, p = 0.001, sensitivity 85.7%, specificity 88%).

Pediatric Pulmonary Hypertension: Definitions, Mechanisms, Diagnosis, and Treatment

Pediatric pulmonary hypertension (PPH) is a multifactorial disease with diverse etiologies and presenting features. Pulmonary hypertension (PH), defined as elevated pulmonary artery pressure, is the presenting feature for several pulmonary vascular diseases. It is often a hidden component of other lung diseases, such as cystic fibrosis and bronchopulmonary dysplasia. Alterations in lung development and genetic conditions are an important contributor to pediatric pulmonary hypertensive disease, which is a distinct entity from adult PH. Many of the causes of pediatric PH have prenatal onset with altered lung development due to maternal and fetal conditions. Since lung growth is altered in several conditions that lead to PPH, therapy for PPH includes both pulmonary vasodilators and strategies to restore lung growth. These strategies include optimal alveolar recruitment, maintaining physiologic blood gas tension, nutritional support, and addressing contributing factors, such as airway disease and gastroesophageal reflux. The outcome for infants and children with PH is highly variable and largely dependent on the underlying cause. The best outcomes are for neonates with persistent pulmonary hypertension (PPHN) and reversible lung diseases, while some genetic conditions such as alveolar capillary dysplasia are lethal. © 2021 American Physiological Society. Compr Physiol 11:2135-2190, 2021.

Fetal endoscopic tracheal occlusion and pulmonary hypertension in moderate congenital diaphragmatic hernia

OBJECTIVE

To study the role of fetal endoscopic tracheal occlusion (FETO) on resolution of pulmonary hypertension (PH) in fetuses with isolated moderate left-sided diaphragmatic hernia (CDH).

METHODS

This retrospective study included fetuses with CDH evaluated between February 2004 and July 2017. Using the tracheal occlusion to accelerate lung growth (TOTAL) trial definition, we classified fetuses into moderate left CDH if O/E-LHR (observed/expected-lung head ratio) was 25-34.9% regardless of liver position or O/E-LHR of 35-44.9% if liver was in the chest. Postnatal echocardiograms were used to diagnose PH. Logistic regression analyses were performed to determine the relationship of FETO with study outcomes.

RESULTS

Of 184 cases with no other major anomalies, 30 (16%) met criteria. There were nine FETO and 21 non-FETO cases. By hospital discharge, a higher proportion of infants in the FETO group had resolution of PH (87.5 (7/8) vs. 40% (8/20); p=.013). FETO was associated with adjusted odds ratio of 17.3 (95% CI: 1.75-171; p=.015) to resolve PH by hospital discharge. No significant differences were noted in need for ECMO or survival to discharge between groups.

CONCLUSIONS

Infants with moderate left-sided CDH according to O/E-LHR, FETO is associated with resolution of PH by the time of hospital discharge.

Neonatal respiratory and cardiac ECMO in Europe

Neonatal extracorporeal membrane oxygenation (ECMO) is a life-saving procedure for critically ill neonates suffering from a potentially reversible disease, causing severe cardiac and/or respiratory failure and refractory to maximal conventional management. Since the 1970s, technology, management, and clinical applications of neonatal ECMO have changed. Pulmonary diseases still represent the principal neonatal diagnosis, with an overall 74% survival rate, and up to one-third of cases are due to congenital diaphragmatic hernia. The overall survival rate in cardiac ECMO is lower, with congenital heart defect representing the main indication. This review provides an overview of the available evidence in the field of neonatal ECMO. We will address the changing epidemiology, basic principles, technologic advances in circuitry, and monitoring, and deliver a current multidisciplinary management framework, focusing on ECMO applications, complications, and long-term morbidities. Lastly, areas for further research will be highlighted.Conclusions: ECMO is a life support with a potential impact on long-term patients' outcomes. In the next years, advances in knowledge, technology, and expertise may push neonatal ECMO boundaries towards more premature and increasingly complex infants, with the final aim to reduce the burden of ECMO-related complications and improve overall patients' outcomes. What is Known: • ECMO is a life-saving option in newborns with refractory respiratory and/or cardiac failure. • The multidisciplinary ECMO management is challenging and may expose neonates to complications with an impact on long-term outcomes. What is New: • Advances in technology and biomaterials will improve neonatal ECMO management and, eventually, the long-term outcome of these complex patients. • Experimental models of artificial placenta and womb technology are under investigation and may provide clinical translation and future research opportunities.

Influence of Gestational Age and Mode of Delivery on Neonatal Outcomes in Prenatally Diagnosed Isolated Congenital Diaphragmatic Hernia

AIM

The optimal gestational age (GA) at delivery and mode of delivery (MoD) for pregnancies with fetal congenital diaphragmatic hernia (CDH) is undetermined. The impact of early term (37-38 weeks 6 days) versus full term (39-40 weeks 6 days) and MoD on immediate neonatal outcomes in prenatally diagnosed isolated CDH cases was evaluated.

MATERIAL AND METHODS

A retrospective chart review of pregnancies evaluated and delivered with the prenatal diagnosis of CDH between July 1, 2008, and December 31, 2018. The primary outcome was survival to hospital discharge. Secondary outcomes included neonatal intensive care unit (NICU) length of stay (LOS), extracorporeal membrane oxygenation (ECMO) requirement and need for supplemental oxygen at day 30 of life.

RESULTS

A total of 296 patients were prenatally evaluated for CDH and delivered in a single center during the study period. After applying exclusion criteria, data were available on 113 women who delivered early term and 72 women who delivered full term. Survival to hospital discharge was comparable between the 2 groups - 83.2% in the early term versus 93.1% in the full term (p = 0.07; 95% CI of 0.13-1.04). No difference was observed in any other secondary outcomes. MoD was stratified into spontaneous vaginal, induced vaginal, unplanned cesarean and scheduled cesarean delivery with associated neonatal survival rates of 74.2, 90.6, 89.7 and 88.2%, respectively, p = 0.13. The 5-min Apgar score was higher in the elective cesarean group (7.94) followed by the induced vaginal delivery group (7.8) compared to 7.17 and 7.18 in the spontaneous vaginal and unplanned cesarean groups, respectively (p = 0.03). The GA and MoD did not influence survival to hospital discharge nor NICU LOS in multivariate analysis.

CONCLUSIONS

Though there were no significant differences in neonatal outcomes for early term compared to full term deliveries of CDH neonates, a trend toward improved survival rates and lower ECMO requirements in the full term group may suggest an underlying importance GA at delivery. Further studies are warranted to validate these findings.

Congenital diaphragmatic hernia: a narrative review of controversies in neonatal management

The consequences of most hernias can be immediately corrected by surgical repair. However, this isn't always the case for children born with a congenital diaphragmatic hernia. The derangements in physiology encountered immediately after birth result from pulmonary hypoplasia and hypertension caused by herniation of abdominal contents into the chest early in lung development. This degree of physiologic compromise can vary from mild to severe. Postnatal management of these children remains controversial. Although heavily studied, multi-institutional randomized controlled trials are lacking to help determine what constitutes best practice. Additionally, the results of the many studies currently within the literature that have investigated differing aspect of care (i.e., inhaled nitric oxide, ventilator type, timing of repair, role of extracorporeal membrane oxygenation, etc.) are difficult to interpret due to the small numbers investigated, the varying degree of physiologic compromise, and the contrasting care that exists between institutions. The aim of this paper is to review areas of controversy in the care of these complex kids, mainly: the use of fraction of inspired oxygen, surfactant therapy, gentle ventilation, mode of ventilation, medical management of pulmonary hypertension (inhaled nitric oxide, sildenafil, milrinone, bosentan, prostaglandins), the utilization of extracorporeal membrane oxygenation, and the timing of surgical repair.

Treatment of pulmonary hypertension during initial hospitalization in a multicenter cohort of infants with congenital diaphragmatic hernia (CDH)

OBJECTIVE

Describe inpatient pulmonary hypertension (PH) treatment and factors associated with therapy at discharge in a multicenter cohort of infants with CDH.

METHODS

Six years linked records from Children's Hospitals Neonatal Database and Pediatric Health Information System were used to describe associations between prenatal/perinatal factors, clinical outcomes, echocardiographic findings and PH medications (PHM), during hospitalization and at discharge.

RESULTS

Of 1106 CDH infants from 23 centers, 62.8% of infants received PHM, and 11.6% of survivors were discharged on PHM. Survivors discharged on PHM more frequently had intrathoracic liver, small for gestational age, and low 5 min APGARs compared with those discharged without PHM (p < 0.0001). Nearly one-third of infants discharged without PHM had PH on last inpatient echo.

CONCLUSIONS

PH medication use is common in CDH. Identification of infants at risk for persistent PH may impact ongoing management. Post-discharge follow-up of all CDH infants with echocardiographic evidence of PH is warranted.

Risk factors for mortality in infants with congenital diaphragmatic hernia: a single center experience

Background

Despite current progress in research of congenital diaphragmatic hernia, its management remains challenging, requiring an interdisciplinary team for optimal treatment.

Objective

Aim of the present study was to evaluate potential risk factors for mortality of infants with congenital diaphragmatic hernia.

Methods

A single-center chart review of all patients treated with congenital diaphragmatic hernia over a period of 16 years, at the Medical University of Vienna, was performed. A comparison of medical parameters between survivors and non-survivors, as well as to published literature was conducted.

Results

During the observational period 66 patients were diagnosed with congenital diaphragmatic hernia. Overall survival was 84.6%. Left-sided hernia occurred in 51 patients (78.5%) with a mortality of 7.8%. In comparison, right-sided hernia occurred less frequently (n = 12) but showed a higher mortality (33.3%, p = 0.000). Critically instable patients were provided with venoarterial extracorporeal membrane oxygenation (ECMO, 32.3%, n = 21). Survival rate among these patients was 66.7%. Right-sided hernia, treatment with inhaled nitric oxide (iNO) over 15 days and the use of ECMO over 10 days were significant risk factors for mortality.

Conclusion

The survival rate in this cohort is comparable to the current literature. Parameters such as the side of the diaphragmatic defect, duration of ECMO and inhaled nitric oxide were assessed as mortality risk factors. This analysis of patients with congenital diaphragmatic hernia enhances understanding of risk factors for mortality, helping to improve management and enabling further evaluation in prospective clinical trials.

Pulmonary hypertension is an important co-morbidity in developmental lung diseases of infancy: Bronchopulmonary dysplasia and congenital diaphragmatic hernia

Bronchopulmonary dysplasia (BPD) following preterm birth and congenital diaphragmatic hernia (CDH) are both forms of developmental lung disease that may result in persistent pulmonary and pulmonary vascular morbidity in childhood. The pulmonary vascular disease (PVD) which accompanies BPD and CDH is due to developmental abnormalities and ongoing perinatal insults. This may be accompanied by evidence of elevated right heart pressures and pulmonary vascular resistance, leading to diagnosis of pulmonary hypertension (PH). The development of PH in these conditions is associated with increased morbidity and mortality in the vulnerable BPD and CDH populations. We present a review of PVD pathogenesis and evaluation in BPD and CDH and discuss management of related sequelae of PH co-morbidity for affected infants.

Early, Postnatal Pulmonary Hypertension Severity Predicts Inpatient Outcomes in Congenital Diaphragmatic Hernia

INTRODUCTION

Pulmonary hypertension (PH) is the major pathophysiologic consequence of congenital diaphragmatic hernia (CDH). We aimed to evaluate the association between early CDH-associated PH (CDH-PH) and inpatient outcomes.

METHODS

The CDH Study Group registry was queried for infants born 2015-2019 with echocardiograms before 48h of life. PH was categorized using echocardiographic findings: none, mild (right ventricular systolic pressure <2/3 systemic), moderate (between 2/3 systemic and systemic), or severe (supra-systemic). Univariate and multivariate analyses were performed. Adjusted Poisson regression was used to assess the primary composite outcome of mortality or oxygen support at 30 days.

RESULTS

Of 1,472 patients, 86.5% had CDH-PH: 13.9% mild (n = 193), 44.4% moderate (n = 631), and 33.2% severe (n = 468). On adjusted analysis, the primary outcome of mortality or oxygen support at 30 days occurred more frequently in infants with moderate (incidence rate ratio [IRR] 1.8, 95% confidence interval [CI], 1.2-2.6) and severe CDH-PH (IRR 2.0, 95% CI, 1.3-2.9). Extracorporeal life support (ECLS) utilization was associated only with severe CDH-PH after adjustment (IRR 1.8, 95% CI, 1.0-3.3).

DISCUSSION/CONCLUSION

Early, postnatal CDH-PH is independently associated with increased risk for mortality or oxygen support at 30 days and utilization of ECLS. Early echocardiogram is a valuable prognostic tool for early, inpatient outcomes in neonates with CDH.