Congenital Diaphragmatic Hernia Study Group. Estimating disease severity of congenital diaphragmatic hernia in the first 5 minutes of life

The promise and pitfalls of care standardization in congenital diaphragmatic hernia

The aim of standardizing care is to enhance patient outcomes and optimize healthcare delivery by minimizing variations in care and ensuring the efficient allocation of healthcare resources. Despite these potential benefits to patients, healthcare providers and the healthcare system, standardization may also disadvantage these groups. With a specific focus on congenital diaphragmatic hernia, this article will review the promise and pitfalls of standardization, as well as a potential path forward that uses standardization to improve outcomes in this rare and complex disease process.

Development of a prediction nomogram for 1-month mortality in neonates with congenital diaphragmatic hernia

OBJECTIVES

Although many prognostic factors in neonates with congenital diaphragmatic hernia (CDH) have been described, no consensus thus far has been reached on which and how many factors are involved. The aim of this study is to analyze the association of multiple prenatal and postnatal factors with 1-month mortality of neonates with CDH and to construct a nomogram prediction model based on significant factors.

METHODS

A retrospective analysis of neonates with CDH at our center from 2013 to 2022 was conducted. The primary outcome was 1-month mortality. All study variables were obtained either prenatally or on the first day of life. Risk for 1-month mortality of CDH was quantified by odds ratio (OR) with 95% confidence interval (CI) in multivariable logistic regression models.

RESULTS

After graded multivariable adjustment, six factors were found to be independently and consistently associated with the significant risk of 1-month mortality in neonates with CDH, including gestational age of prenatal diagnosis (OR, 95% CI, P value: 0.845, 0.772 to 0.925, < 0.001), observed-to-expected lung-to-head ratio (0.907, 0.873 to 0.943, < 0.001), liver herniation (3.226, 1.361 to 7.648, 0.008), severity of pulmonary hypertension (6.170, 2.678 to 14.217, < 0.001), diameter of defect (1.560, 1.084 to 2.245, 0.017), and oxygen index (6.298, 3.383 to 11.724, < 0.001). Based on six significant factors identified, a nomogram model was constructed to predict the risk for 1-month mortality in neonates with CDH, and this model had decent prediction accuracy as reflected by the C-index of 94.42%.

CONCLUSIONS

Our findings provide evidence for the association of six preoperational and intraoperative factors with the risk of 1-month mortality in neonates with CDH, and this association was reinforced in a nomogram model.

Pulmonary Artery Measurements as Postnatal Prognostic Tool in Right Congenital Diaphragmatic Hernia

BACKGROUND

Right-sided congenital diaphragmatic hernia (RCDH) is a rare and often fatal congenital anomaly, primarily attributed to lung hypoplasia, which is associated with small branch pulmonary artery (PA). This study investigated whether postnatal PA measurements obtained through echocardiography are associated with mortality or the extracorporeal membrane oxygenation (ECMO) requirement in neonates with RCDH.

METHODS

A retrospective study was conducted on neonates with RCDH born between 2008 and 2022. Echocardiography was performed on the day of birth. The diameter of the main PA (MPA) was measured at the maximal dimension, and the diameters of the left PA (LPA) and right PA (RPA) were measured at the bifurcation. The primary outcome was mortality or ECMO requirement. Parameters, including the LPA:MPA ratio, RPA:MPA ratio, Nakata index, McGoon ratio, and ejection fraction (EF), were analyzed and compared with the observed-to-expected lung-to-head ratio (o/e LHR), initial blood gas, and defect size as predictive values.

RESULTS

Among 39 neonates with RCDH, 25 (64.1 %) survived without ECMO. The non-survivor or ECMO group exhibited lower o/e LHR, reduced EF, smaller LPA and RPA diameters, and larger MPA diameter than survivors. Lower LPA:MPA ratio, Nakata index, McGoon ratio, and higher initial PaCO2 were associated with adverse outcomes. Notably, the LPA:MPA ratio showed the highest predictive capability (area under the curve, 0.983; p < 0.001).

CONCLUSION

The LPA:MPA ratio is a promising postnatal predictor of mortality or ECMO requirement in neonates with RCDH. Additionally, Nakata index, McGoon ratio, and initial PaCO2 are significantly correlated with outcomes.

LEVEL OF EVIDENCE

This is a level III.

TYPE OF STUDY

Prognostic study.

Predictors of Mortality in Very Low Birth Weight Neonates With Congenital Diaphragmatic Hernia

BACKGROUND

Limited data exists regarding the mortality of very low birth weight (VLBW) neonates with congenital diaphragmatic hernia (CDH). This study aims to quantify and determine predictors of mortality in VLBW neonates with CDH.

METHODS

This analysis of 829 U.S. NICUs included VLBW [birth weight ≤1500g] neonates, born 2011-2021 with and without CDH. The primary outcome was in-hospital mortality. A generalized estimating equation regression model determined the adjusted risk ratio (ARR) of mortality.

RESULTS

Of 426,140 VLBW neonates, 535 had CDH. In neonates with CDH, 48.4% had an additional congenital anomaly vs 5.5% without. In-hospital mortality for neonates with CDH was 70.4% vs 12.6% without. Of those with CDH, 73.3% died by day of life 3. Of VLBW neonates with CDH, 38% were repaired. A subgroup analysis was performed on 60% of VLBW neonates who underwent delivery room intubation or mechanical ventilation, as an indicator of active treatment. Mortality in this group was 62.7% for neonates with CDH vs 16.4% without. Higher Apgars at 1 min and repair of CDH were associated with lower mortality (ARR 0.91; 95%CI 0.87,0.96 and ARR 0.28; 0.21,0.39). The presence of additional congenital anomalies was associated with higher mortality (ARR 1.14; 1.01,1.30).

CONCLUSION

These benchmark data reveal that VLBW neonates with CDH have an extremely high mortality. Almost half of the cohort have an additional congenital anomaly which significantly increases the risk of death. This study may be utilized by providers and families to better understand the guarded prognosis of VLBW neonates with CDH.

TYPE OF STUDY

Level II.

LEVEL OF EVIDENCE

Level II.

The role of extracorporeal life support and timing of repair in infants with congenital diaphragmatic hernia

Extracorporeal life support (ECLS) serves as a rescue therapy for patients with congenital diaphragmatic hernia (CDH) and severe cardiopulmonary failure, and only half of these patients survive to discharge. This costly intervention has a significant complication risk and is reserved for patients with the most severe disease physiology refractory to maximal cardiopulmonary support. Some contraindications to ECLS do exist such as coagulopathy, lethal chromosomal or congenital anomaly, very preterm birth, or very low birth weight, but many of these limits are being evaluated through further research. Consensus guidelines from the past decade vary in recommendations for ECLS use in patients with CDH but this therapy appears to have a survival benefit in the most severe subset of patients. Improved outcomes have been observed for patients treated at high-volume centers. This review details the evolving literature surrounding management paradigms for timing of CDH repair for patients receiving preoperative ECLS. Most recent data support early repair following cannulation to avoid non-repair which is uniformly fatal in this population. Longer ECLS runs are associated with decreased survival, and patient physiology should guide ECLS weaning and eventual decannulation rather than limiting patients to arbitrary run lengths. Standardization of care across centers is a major focus to limit unnecessary costs and improve short-term and long-term outcomes for these complex patients.

The CDH Study Group: Past, Present, and Future

The Congenital Diaphragmatic Hernia Study Group (CDHSG) is an international consortium of medical centers actively collecting and voluntarily contributing data pertaining to live born congenital diaphragmatic hernia (CDH) patients born and/or managed at their institutions. These data are aggregated to construct a comprehensive registry that participating centers can access to address specific clinical inquiries and track patient outcomes. Since its establishment in 1995, 147 centers have taken part in this initiative, including 53 centers from 17 countries outside the United States, with 95 current active centers across the globe. The registry has amassed data on over 14,000 children, resulting in the creation of over 75 manuscripts based on registry data to date. International, multicenter consortia enable health care professionals managing uncommon, complex, and diverse diseases to formulate evidence-based hypotheses and draw meaningful and generalizable conclusions for clinical inquiries. This review will explore the formation and structure of the CDHSG and its registry, outlining their functions, center participation, and the evolution of data collection. Additionally, we will provide an overview of the evidence generated by the CDHSG, with a particular emphasis on contributions post-2014, and look ahead to the future directions the study group will take in addressing CDH.

Early Ventilator Management for Infants With Congenital Diaphragmatic Hernia: Impact of a Standardized Clinical Practice Guideline

BACKGROUND

Infants with congenital diaphragmatic hernia (CDH) experience high morbidity and mortality due to pulmonary arterial hypertension and hypoplasia. Mechanical ventilation is a central component of CDH management. Our objective was to evaluate the impact of a standardized clinical practice guideline (implemented in January 2012) on ventilator management for infants with CDH, and associate management changes with short-term outcomes, specifically extracorporeal membrane oxygenation (ECMO) utilization and survival to discharge.

METHODS

We conducted a retrospective pre-post study of 103 CDH infants admitted from January 2007-July 2021, divided pre- (n = 40) and post-guideline (n = 63). Clinical outcomes, ventilator settings, and blood gas values in the first 7 days of mechanical ventilation were compared between the pre- and post-guideline cohorts.

RESULTS

Post-guideline, ECMO utilization decreased (11% vs 38%, p = 0.001) and survival to discharge improved (92% vs 68%, p = 0.001). More post-guideline patients remained on conventional mechanical ventilation without need for escalation to high-frequency ventilation or ECMO, and had higher pressures and PaCO2 with lower FiO2 and PaO2 (p < 0.05).

CONCLUSIONS

Standardized ventilator management optimizing pressures for adequate lung expansion and minimizing oxygen toxicity improves outcomes for infants with CDH.

LEVEL OF EVIDENCE

III.

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.

Extracorporeal life support in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is the most common indication for ECLS in neonatal respiratory failure. The ultimate purpose of ECLS is to grant cardiopulmonary support, allowing time for operative intervention and optimization of cardiopulmonary function as the pathophysiologic processes of pulmonary hypertension, pulmonary hypoplasia, and ventricular dysfunction either improve or resolve. In CDH, ECLS plays a crucial role in the management of the most challenging patients, facilitating postnatal stabilization, allowing a ventilation strategy which minimizes barotrauma and volutrauma, and permitting treatment of and recovery from pulmonary hypertension and/or cardiac dysfunction. Understanding the nuances of CDH patients, which differ from other forms of neonatal respiratory failure, and the benefits of ECLS for these infants, is crucial for effective management. CDH patients present distinct challenges. Every aspect of ECLS, from mode of support and anticoagulation medication to pump selection, ventilation strategy, pulmonary hypertension management, and the weaning process, requires meticulous consideration. ECLS for CDH serves as a bridge to making informed decisions, granting clinicians stability and time to manage / recover from specific pathophysiologic consequences, and it offers the potential for survival among even the most challenging and complex patients. As overall care and management for infants with CDH receiving ECLS continue to improve, the focus has shifted toward managing survivor morbidity. Given the multisystem nature of the disease, this requires significant experience, expertise, and multidisciplinary teamwork to optimize long-term outcomes for these patients.

A novel congenital diaphragmatic hernia prediction model for Chinese subjects: A multicenter cohort investigation

Purpose of the study

Brindle et al. (2014) and the Congenital Diaphragmatic Hernia Study Group constructed a simplified clinical prediction rule (Brindle score) to stratify infants with congenital diaphragmatic hernia based on disease severity. We aimed to develop a predictive model applicable to Chinese patients with congenital diaphragmatic hernia and externally validate whether the Brindle score is applicable to the Chinese population.

Patients and the methods

Multiple imputations supplemented the missing data. A least absolute shrinkage and selection operator regression was used to screen the factors influencing adverse outcomes. Internal validation was performed by bootstrap resampling. The C-index, area under the receiver operating characteristic curve, and the Hosmer-Lemeshow test evaluated the predictive power.

Results

A nomogram named "CCDH score" (Chinese Congenital Diaphragmatic Hernia score), including pulmonary hypertension, low 5-min Apgar score (<7), chromosomal anomaly, major cardiac anomalies (MCAs), observed-to-expected lung-to-head ratio, and the percentage of liver herniation, was constructed. The CCDH score revealed good calibration and discriminative abilities, with a C-index of 0.941. In the training and external validation cohorts, the area under the receiver operating characteristic curve of the Brindle score were 0.820 and 0.881, respectively. The Brindle score has fair predictive power in the Chinese population, but the newly established CCDH score seems more suitable for Chinese patients with congenital diaphragmatic hernia.

Conclusion

The CCDH score is the first predictive model constructed based on the characteristics of the Chinese population and can accurately predict the survival outcomes of patients with congenital diaphragmatic hernia.

Mortality in Congenital Diaphragmatic Hernia: A Multicenter Registry Study of Over 5000 Patients Over 25 Years

OBJECTIVE

To determine if risk-adjusted survival of patients with CDH has improved over the last 25 years within centers that are long-term, consistent participants in the CDH Study Group (CDHSG).

SUMMARY BACKGROUND DATA

The CDHSG is a multicenter collaboration focused on evaluation of infants with CDH. Despite advances in pediatric surgical and intensive care, CDH mortality has appeared to plateau. Herein, we studied CDH mortality rates amongst long-term contributors to the CDHSG.

METHODS

We divided registry data into 5-year intervals, with Era 1 (E1) beginning in 1995, and analyzed multiple variables (operative strategy, defect size, and mortality) to assess evolution of disease characteristics and severity over time. For mortality analyses, patients were risk stratified using a validated prediction score based on 5-minute Apgar (Apgar5) and birth weight. A risk-adjusted, observed to expected (O:E) mortality model was created using E1 as a reference.

RESULTS

5203 patients from 23 centers with >22years of participation were included. Birth weight, Apgar5, diaphragmatic agenesis, and repair rate were unchanged over time (all P > 0.05). In E5 compared to E1, minimally invasive and patch repair were more prevalent, and timing of diaphragmatic repair was later (all P < 0.01). Overall mortality decreased over time: E1 (30.7%), E2 (30.3%), E3 (28.7%), E4 (26.0%), E5 (25.8%) ( P = 0.03). Risk-adjusted mortality showed a significant improvement in E5 compared to E1 (OR 0.78, 95% CI 0.62-0.98; P = 0.03). O:E mortality improved over time, with the greatest improvement in E5.

CONCLUSIONS

Risk-adjusted and observed-to-expected CDH mortality have improved over time.

Congenital Diaphragmatic Hernia: Perinatal Prognostic Factors and Short-Term Outcomes in a Single-Center Series

Background: Many prognostic factors for CDH patients are described and validated in the current literature: the size of diaphragmatic defects, need for patch repair, pulmonary hypertension and left ventricular dysfunction are recognized as the most influencing outcomes. The aim of this study is to analyze the influence of these parameters in the outcome of CDH patients in our department and identify any further prognostic factors. Methods: An observational retrospective single-center study was conducted including all patients treated at our centre with posterolateral CDH between 01.01.1997 and 12.31.2019. The main outcomes evaluated were mortality and length of hospital stay. A univariate and multivariate analysis was performed. Results: We identified 140 patients with posterolateral CDH; 34.8% died before discharge. The overall median length of stay was 24 days. A univariate analysis confirmed that both outcomes are associated with the size of diaphragmatic defects, need for patch repair and presence of spleen-up (p < 0.05). A multivariate analysis identified that the need for patch repair and maximum dopamine dose used for cardiac dysfunction are independent parameters associated with the length of stay only (p < 0.001). Conclusions: In our series, the duration of hospitalization is longer for newborns with CDH treated with higher doses of dopamine for left ventricular dysfunction or needing patch repair in large diaphragmatic defects.

Isolated aortic arch anomalies are associated with defect severity and outcome in patients with congenital diaphragmatic hernia

PURPOSE

Congenital diaphragmatic hernia (CDH) patients often have suspected isolated aortic arch anomalies (IAAA) on imaging. The purpose of this work was to describe the incidence and outcomes of CDH + IAAA patients.

METHODS

Cardiovascular data were collected for infants from the CDH Study Group born between 2007 and 2019. IAAA were defined as coarctation of aorta, hypoplastic aortic arch, interrupted aortic arch, and aortic aneurysmal disease on early, postnatal echocardiography. Patients with major cardiac malformations and/or chromosomal abnormalities were excluded. Primary outcomes included the rate of aortic intervention, rates of extracorporeal life support (ECLS) utilization, and mortality.

RESULTS

Of 6357 CDH infants, 432 (7%) were diagnosed with a thoracic aortic anomaly. Of these, 165 were diagnosed with IAAA, most commonly coarctation of the aorta (n = 106; 64%) or hypoplastic aortic arch (n = 58; 35%). CDH + IAAA patients had lower birthweights (3 kg vs. 2.9 kg) and Apgar scores (7 vs. 6) than patients without IAAA (both χ² p < 0.001). CDH + IAAA were less likely to undergo diaphragm repair (72 vs. 87%, p < 0.001), and overall mortality was higher for CDH + IAAA infants (58 vs. 24%, p < 0.001). When controlling for defect size, birth weight, and Apgar, IAAA were significantly associated with mortality (OR 3.3, 95% CI 2.2-5.0; p < 0.01) but not associated with ECLS (OR 0.98, 95% CI 0.65-1.50; p = 0.90). Only 17% (n = 28) of CDH + IAAA patients underwent aortic intervention.

CONCLUSIONS

IAAA in CDH are associated with increased mortality. This often simply reflects severity of the defect and thoracic anatomic derangement, as opposed to unique aortic pathology, given few CDH + IAAA patients undergo aortic intervention.

Association of timing of congenital diaphragmatic hernia repair with survival and morbidity for patients not requiring extra-corporeal life support

BACKGROUND

While physiologic stabilization followed by repair has become the accepted paradigm for management of congenital diaphragmatic hernia (CDH), few studies have examined the effect of incremental changes in operative timing on patient outcomes. We hypothesized that later repair would be associated with higher morbidity and mortality.

METHODS

Data were queried from the CDH Study Group (CDHSG) from 2007-2020. Patients with chromosomal or cardiac abnormalities and those who were never repaired or required pre-repair extra-corporeal life support (ECLS) were excluded. Time to repair was analyzed both as a continuous variable and by splitting the cohort into top/bottom percentiles. The primary outcome of interest was in-hospital mortality. Secondary outcomes included need for and duration of post-repair ventilatory and nutritional support.

RESULTS

A total of 4,104 CDH infants were included. Median time to repair was 4 days (IQR 2-6). On multivariable analysis, high-risk (CDHSG stage C/D) defects and lower birthweight predicted later repair. Overall, in-hospital mortality was 6%. On univariate analysis, there was no difference in the number of days to repair between survivors and non-survivors. On risk-adjusted analysis, single-day changes in day of repair were not associated with increased mortality. Later repair was associated with longer time to reach full oral feeds, increased post-repair ventilator days, and increased need for tube feeds and supplementary oxygen at discharge.

CONCLUSIONS

For infants with isolated CDH not requiring pre-operative ECLS, there is no difference in mortality based on timing of repair, but single-day delays in repair are associated with increased post-repair duration of ventilatory and nutritional support.

Development and internal validation of a prediction model to predict survival for congenital diaphragmatic hernia in the early postnatal period

PURPOSE

To develop an easily applied predictive model to predict survival rate for infants with congenital diaphragmatic hernia (CDH) in the early postnatal period according to the Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis (TRIPOD) guideline.

METHODS

The retrospective study was conducted including 225 neonates with prenatal or postnatal diagnosed CDH between 2001 and 2018. Patients did not receive the therapy of fetal endoscopic tracheal occlusion and extracorporeal membrane oxygenation. The study took into consideration these variables that are easily available in most centers within the first 1 h after admission. A multivariable prediction model to predict the survival rate for CDH was generated and its performance was analyzed.

RESULTS

The multiple logistic regression analysis was generated using five clinical variables that are routinely available in most centers, including birth weight, 1-min Apgar score, side of hernia, presence of liver herniation, and PaCO₂ in the admission arterial blood analysis. The area under the receiver operating characteristic curve value for this model was 0.912, which was greater than that of a single biomarker in predicting the survival rate of CDH. This model had a sensitivity of 90.6% and a specificity of 74.6%. This model demonstrated good calibration (Hosmer-Lemeshow goodness-of-fit test, p = .410). Besides, the model had a better discriminative ability compared to the previously established predictive models of CDH.

CONCLUSIONS

The simple and generalizable model was developed by five predictors for CDH in the early period using the TRIPOD checklist. It demonstrated good performance in predicting the survival rate of infants with CDH, holding promise for future clinical application.

Variation across centers in standardized mortality ratios for congenital diaphragmatic hernia receiving extracorporeal life support

BACKGROUND

We sought to elucidate the degree of variation across centers by calculating center-specific standardized mortality ratios (SMRs) for infants with congenital diaphragmatic hernia (CDH) requiring extracorporeal life support (ECLS).

METHODS

The Extracorporeal Life Support Organization (ELSO) registry data (2000-2019) were used to estimate SMRs. Center-specific SMRs and their 95% confidence intervals (CIs) were used to identify centers with mortality as significantly worse (SW), significantly better (SB), or not different (ND) relative to the median standardized mortality rate.

RESULTS

We identified 4,223 neonates with CDH from 109 centers. SMRs were risk-adjusted for pre-ECLS case-mix (birthweight, sex, race, 5 min Apgar, blood gases, gestational age, hernia side, prenatal diagnosis, pre-ECLS arrest, and comorbidities). Observed (unadjusted) mortality rates across centers varied substantially (range: 14.3%-90.9%; interquartile range [IQR]: 42.9%-62.1%). Thirteen centers (11.9%) had SB SMRs< 1 (SMR 0.52 to 0.84), 7 centers (6.4%) had SW SMRs>1 (SMR 1.25 to 1.43), and 89 centers (81.7%) had SMRs ND relative to the median SMR rate across all centers (i.e., SMR not different from one). Descriptive analyses demonstrated that SB centers had a lower proportion of cases with renal complications, infectious complications and discontinuation of ECLS owing to complications, as well as differences in pre-ECLS treatments and timing of CDH repair, compared to SW and ND centers.

CONCLUSION

This study specifically identified ECLS centers with higher and lower survival for patients with CDH, which may serve as a benchmark for institutional quality improvement. Future studies are needed to identify those specific processes at those centers that leads to favorable outcomes with the goal of improving care globally.

LEVEL OF EVIDENCE

Level III.

Image-based prenatal predictors correlate with postnatal survival, extracorporeal life support use, and defect size in left congenital diaphragmatic hernia

OBJECTIVE

To evaluate the association between prenatal imaging predictors of patients with left-sided congenital diaphragmatic hernia (LCDH) and postnatal outcomes.

STUDY DESIGN

CDH study group data were reviewed for LCDH infants born 2015-2019. Prenatal ultrasound (US) and magnetic resonance imaging (MRI) data were collected and correlated with postnatal information including CDHSG defect size (A through D or non-repair (NR)).

RESULTS

In total, 929 LCDH patients were included. Both US and MRI imaging predictors correlated with postnatal survival (72.2%) and ECLS use (29.6%). Logistic regression models confirmed increased survival and decreased ECLS use with larger values for all predictors. Importantly, all prenatal values evaluated showed no significant difference between defect size D and NR patients.

CONCLUSIONS

This is the largest cohort of LCDH patients and demonstrates that prenatal imaging factors correlate with postnatal outcomes and confirms that patients in the non-repair group are prenatally similar to type D defects.

Congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a rare birth defect characterized by incomplete closure of the diaphragm and herniation of fetal abdominal organs into the chest that results in pulmonary hypoplasia, postnatal pulmonary hypertension owing to vascular remodelling and cardiac dysfunction. The high mortality and morbidity rates associated with CDH are directly related to the severity of cardiopulmonary pathophysiology. Although the aetiology remains unknown, CDH has a polygenic origin in approximately one-third of cases. CDH is typically diagnosed with antenatal ultrasonography, which also aids in risk stratification, alongside fetal MRI and echocardiography. At specialized centres, prenatal management includes fetal endoscopic tracheal occlusion, which is a surgical intervention aimed at promoting lung growth in utero. Postnatal management focuses on cardiopulmonary stabilization and, in severe cases, can involve extracorporeal life support. Clinical practice guidelines continue to evolve owing to the rapidly changing landscape of therapeutic options, which include pulmonary hypertension management, ventilation strategies and surgical approaches. Survivors often have long-term, multisystem morbidities, including pulmonary dysfunction, gastroesophageal reflux, musculoskeletal deformities and neurodevelopmental impairment. Emerging research focuses on small RNA species as biomarkers of severity and regenerative medicine approaches to improve fetal lung development.

Clinical trials and outcome reporting in congenital diaphragmatic hernia overlook long-term health and functional outcomes-A plea for core outcomes

Aim

To review the selection, measurement and reporting of outcomes in studies of interventions in Congenital Diaphragmatic Hernia (CDH).

Methods

We searched the Cochrane Central Register of Controlled Trials from 2000–2020 for randomised trials and observational studies. Outcomes reported were classified into seven key domains modelled on the patient journey.

Results

Our search yielded 118 papers; 27 were eligible. The most frequent domains measured were ‘short‐term markers of disease activity’ (17/27), whereas long‐term outcomes (3/27) and outcomes relating to functional health status (8/27) were reported infrequently. There was heterogeneity in the methods and timing of outcome reporting. Primary outcomes were varied and not always clearly stated.

Conclusion

Long‐term health and functional outcomes involving interventional studies in CDH are infrequently reported, which hinders the process of shared decision‐making and evidence‐based healthcare. A CDH core outcome set is needed to standardise outcome reporting that is relevant to both families and healthcare teams.

Center Volume and Cost-Effectiveness in the Treatment of Congenital Diaphragmatic Hernia (CDH)

BACKGROUND

The care of patients with congenital diaphragmatic hernia (CDH) is expensive, yet little is known about variability in cost-of-care for these patients. The purpose of this study was to examine the cost-effectiveness of CDH treatment, comparing high- versus low-volume centers.

METHODS

This is a retrospective study of neonatal patients with CDH at U.S. hospitals using data from the Pediatric Health Information System database (2015-2018). Centers were considered high-volume if they had ≥10 patients with CDH for ≥ 2 y. Cost-effectiveness analysis was performed with cost per survivor as the outcome measure, and probabilistic sensitivity analysis was performed.

RESULTS

A total of 1687 patients were included in the study. Overall mortality was 24.4%. Patients at high-volume centers had a longer mean length of stay (64 d versus 48 d for low-volume centers, P = 0.0001) and higher extracorporeal life support (ECLS) rates (32% versus 24%, P = 0.002). Risk-adjusted mortality did not differ between high- and low-volume centers (23.9% versus 25.9%, P = 0.39), except when ECLS was involved (42% versus 56%, P = 0.011). Costs were significantly higher at high-volume centers ($395,291 ± 508,351 versus $255,074 ± 308,802, P < 0.0001). Survival status, ECLS use, operative repair, length of stay, high-volume status, and gestational age were identified as independent drivers of cost. On cost-effectiveness analysis, low-volume hospitals were more cost-effective in 95% of simulations.

CONCLUSIONS

High-volume centers have substantially higher costs without an associated survival benefit and are less cost-effective than low-volume centers. Standardization of care is necessary to minimize the delivery of low-value care.

Prediction of survival in infants with congenital diaphragmatic hernia and the response to inhaled nitric oxide

The use of inhaled nitric oxide (iNO) in treating pulmonary hypertension in infants with congenital diaphragmatic hernia (CDH) is controversial. Our aims were to identify factors associated with survival in CDH infants and whether this was influenced by the response to iNO. Results of CDH infants treated in a tertiary surgical and medical perinatal centre in a ten year period (2011-2021) were reviewed. Factors affecting survival were determined. To assess the response to iNO, blood gases prior to and 30 to 60 min after initiation of iNO were analysed and PaO₂/FiO₂ ratios and oxygenation indices (OI) calculated. One hundred and five infants were admitted with CDH; 46 (43.8%) infants died. The CDH infants who died had a lower median observed to expected lung to head ratio (O/E LHR) (p < 0.001) and a higher median highest OI on day 1 (HOId1) (p < 0.001). HOId1 predicted survival after adjusting for gestational age, Apgar score at 5 min and O/E LHR (odds ratio 0.948 (95% confidence intervals 0.913-0.983)). Seventy-two infants (68.6%) received iNO; 28 survived to discharge. The median PaO₂ (46.7 versus 58.8 mmHg, p < 0.001) and the median PaO₂/FiO₂ ratio (49.4 versus 58.8, p = 0.003) improved post iNO initiation. The percentage change in the PaO₂/FiO₂ ratio post iNO initiation was higher in infants who survived (69.4%) compared to infants who died (10.2%), p = 0.018.

CONCLUSION

The highest OI on day 1 predicted survival. iNO improved oxygenation in certain CDH infants and a positive response was more likely in those who survived.

WHAT IS KNOWN

• The use of iNO is controversial in infants with CDH with respect to whether it improves survival.

WHAT IS NEW

• We have examined predictors of survival in CDH infants including the response to iNO and demonstrated that the highest oxygenation index on day 1 predicted survival (AUCROC =0.908). • Certain infants with CDH responded to iNO and those with a greater response were more likely to survive.

Survival Benefit Associated With the Use of Extracorporeal Life Support for Neonates With Congenital Diaphragmatic Hernia

OBJECTIVE

To measure the survival among comparable neonates with CDH supported with and without ECLS.

SUMMARY OF BACKGROUND DATA

Despite widespread use in the management of newborns with CDH, ECLS has not been consistently associated with improved survival.

METHODS

A retrospective cohort study was performed using ECLS-eligible CDH Study Group registry patients born between 2007 and 2019. The primary outcome was in-hospital mortality. Neonates who did and did not receive ECLS were matched based on variables affecting risk for the primary outcome. Iterative propensity score-matched, survival (Cox regression and Kaplan-Meier), and center effects analyses were performed to examine the association of ECLS use and mortality.

RESULTS

Of 5855 ECLS-eligible CDH patients, 1701 (29.1%) received ECLS. "High-risk" patients were best defined as those with a lowest achievable first-day arterial partial pressure of CO2 of ≥60 mm Hg. After propensity score matching, mortality was higher with ECLS (47.8% vs 21.8%, odds ratio 3.3, 95% confidence interval 2.7-4.0, hazard ratio 2.3, P < 0.0001). For the subgroup of high-risk patients, there was lower mortality observed with ECLS (64.2% vs 84.4%, odds ratio 0.33, 95% confidence interval 0.17-0.65, hazard ratio 0.33, P = 0.001). This survival advantage was persistent using multiple matching approaches. However, this ECLS survival advantage was found to occur primarily at high CDH volume centers that offer frequent ECLS for the high-risk subgroup.

CONCLUSIONS

Use of ECLS is associated with excess mortality for low- and intermediate-risk neonates with CDH. It is associated with a significant survival advantage among high-risk infants, and this advantage is strongly influenced by center CDH volume and ECLS experience.

A nationwide database analysis of demographics and outcomes related to Extracorporeal Membrane Oxygenation (ECMO) in congenital diaphragmatic hernia

PURPOSE

The aim of the study was to understand the use of Extracorporeal Membrane Oxygenation (ECMO) in congenital diaphragmatic hernia (CDH) and its outcomes.

METHODS

The 2016 Kid's Inpatient Database (KID) obtained from the national Healthcare Cost and Utilization Project (HCUP) was used to obtain CDH birth, demographic, and outcome data associated with ECMO use. Categorical variables were analyzed and odds ratios (OR) with 95% confidence intervals (CI) are reported for variables found to have significance (p < 0.05). Appropriate regressions were used for comparing categorical and continuous data using SPSS 25 for Macintosh.

RESULTS

The database contained 1189 cases of CDH, of which 133 (11.2%) received ECMO. The overall mortality of neonates with CDH was 18.9% (225/1189). Newborns with CDH on ECMO had a survival of 46% (61/133) compared to 85.5% without ECMO (903/1056) (OR 6.966, p < 0.001, 95% CI 4.756-10.204). ECMO increased length of stay from 24.6 to 69.8 days (OR 2.834, p < 0.001, 95% CI 2.768-2.903) and average cost from $375,002.20 to $1641,586.83 (OR 4.378, p < 0.001, 95% CI 3.341-5.735).

CONCLUSIONS

Increased length of stay, costs, and outcomes with ECMO use in CDH should prompt an examination of criteria necessitating ECMO.

Birth weight predicts patient outcomes in infants who undergo congenital diaphragmatic hernia repair

PURPOSE

The purpose of this study was to analyze the clinical characteristics and outcomes of low birthweight (LBW) infants with congenital diaphragmatic hernia (CDH) compared to normal birthweight (NBW) infants with CDH. We hypothesized that LBW was associated with increased mortality, decreased extracorporeal life support (ECLS) utilization, and increased pulmonary morbidity in CDH patients.

METHODS

Patients in the CDH Study Group from 2007 to 2018 were included. LBW was defined as <2.5 kg. Clinical characteristics and outcomes for LBW patients were compared to normal birthweight (NBW) patients using univariate and multivariable analyses.

RESULTS

Of 5,586 patients, 1,157 (21%) were LBW. LBW infants had more congenital anomalies and larger diaphragmatic defects than NBW infants. ECLS utilization was decreased, and overall mortality was increased among LBW infants compared to NBW infants. A 1 kg increase in birthweight was associated with 34% higher odds of survival after repair (adjusted Odds Ratio 1.34, 95% CI 1.03-1.76; p = .03). LBW infants had longer durations of mechanical ventilation and were more likely to require supplemental oxygen at 30 days and at the time of discharge.

CONCLUSION

LBW is a risk factor for mortality and pulmonary morbidity in CDH. Prolonged oxygen requirement and increased length of stay are important considerations when managing this population.

Risk Factors for Hemolysis During Extracorporeal Life Support for Congenital Diaphragmatic Hernia

BACKGROUND

Neonates receiving extracorporeal life support (ECLS) for congenital diaphragmatic hernia (CDH) require prolonged support compared with neonates with other forms of respiratory failure. Hemolysis is a complication that can be seen during ECLS and can lead to renal failure and potentially to worse outcomes. The purpose of this study was to identify risk factors for the development of hemolysis in CDH patients treated with ECLS.

METHODS

The Extracorporeal Life Support Organization database was used to identify infants with CDH (2000-2015). The primary outcome was hemolysis (plasma-free hemoglobin >50 mg/dL). Potentially associated variables were identified in the data set. Descriptive statistics and a series of nested multivariable logistic regression models were used to identify associations between hemolysis and demographic, pre-ECLS, and on-ECLS factors.

RESULTS

There were 4576 infants with a mortality of 52.5%. The overall mean rate of hemolysis was 10.5% during the study period. In earlier years (2000-2005), the hemolysis rates were 6.3% and 52.7% for roller versus centrifugal pumps, whereas in later years (2010-2015), they were 2.9% and 26.5%, respectively. The fully adjusted model demonstrated that the use of centrifugal pumps was a strong predictor of hemolysis (odds ratio: 6.67, 95% confidence interval: 5.14-8.67). In addition, other risk factors for hemolysis included low 5-min Apgar score, on-ECLS complications (renal, metabolic, and cardiovascular), and duration of ECLS.

CONCLUSIONS

In our cohort of CDH patients receiving ECLS over 15 y, the use of centrifugal pumps increased over time, along with the rate of hemolysis. Patient- and treatment-level risk factors were identified contributing to the development of hemolysis.

Sources of regional and center-level variability in survival and cost of care for congenital diaphragmatic hernia (CDH)

PURPOSE

Enormous variability in management and cost occurs in CDH care. The purpose of this study was to identify regional mortality and cost patterns underlying this variability.

METHODS

This is a retrospective study of neonatal CDH patients at U.S. hospitals using data from the Pediatric Health Information System (PHIS) database (2015-2018). Patients were risk-stratified using CDH Study Group predicted survival (CDHSG-PS), and mortality and costs were assessed by region (East, West, Mid-West, and South) and center.

RESULTS

Higher mortality and extracorporeal life support (ECLS) rates were found in the Mid-West and South (p<0.0001). Higher mortality was seen with ECLS among low-volume centers in the South (p=0.007). When broken down by CHDSG-PS, higher severity patients had higher mortality in the Mid-West and South (p=0.038). Cost was significantly lower for high severity nonsurvivors than survivors ($244,005 vs $565,487, p=0.0008). The East spent more on high-severity patients with lower mortality compared to other regions, but also spent 3.5 times more on low severity nonsurvivors than survivors. Costs were higher at high-volume centers for low- and medium-severity patients, but all centers spent the same on high-severity patients.

CONCLUSION

Center volume, region, and patient severity all contribute to the complex survival and cost disparities that exist in CDH care. Standardization of care may improve survival and reduce cost variability.

TYPE OF STUDY

Retrospective database study.

LEVEL OF EVIDENCE

Level II.

Unraveling the Genetics of Congenital Diaphragmatic Hernia: An Ongoing Challenge

Congenital diaphragmatic hernia (CDH) is a congenital structural anomaly in which the diaphragm has not developed properly. It may occur either as an isolated anomaly or with additional anomalies. It is thought to be a multifactorial disease in which genetic factors could either substantially contribute to or directly result in the developmental defect. Patients with aneuploidies, pathogenic variants or de novo Copy Number Variations (CNVs) impacting specific genes and loci develop CDH typically in the form of a monogenetic syndrome. These patients often have other associated anatomical malformations. In patients without a known monogenetic syndrome, an increased genetic burden of de novo coding variants contributes to disease development. In early years, genetic evaluation was based on karyotyping and SNP-array. Today, genomes are commonly analyzed with next generation sequencing (NGS) based approaches. While more potential pathogenic variants are being detected, analysis of the data presents a bottleneck-largely due to the lack of full appreciation of the functional consequence and/or relevance of the detected variant. The exact heritability of CDH is still unknown. Damaging de novo alterations are associated with the more severe and complex phenotypes and worse clinical outcome. Phenotypic, genetic-and likely mechanistic-variability hampers individual patient diagnosis, short and long-term morbidity prediction and subsequent care strategies. Detailed phenotyping, clinical follow-up at regular intervals and detailed registries are needed to find associations between long-term morbidity, genetic alterations, and clinical parameters. Since CDH is a relatively rare disorder with only a few recurrent changes large cohorts of patients are needed to identify genetic associations. Retrospective whole genome sequencing of historical patient cohorts using will yield valuable data from which today's patients and parents will profit Trio whole genome sequencing has an excellent potential for future re-analysis and data-sharing increasing the chance to provide a genetic diagnosis and predict clinical prognosis. In this review, we explore the pitfalls and challenges in the analysis and interpretation of genetic information, present what is currently known and what still needs further study, and propose strategies to reap the benefits of genetic screening.

Prevalence and mortality in children with congenital diaphragmatic hernia: a multicountry study

PURPOSE

This study determined the prevalence, mortality, and time trends of children with congenital diaphragmatic hernia (CDH).

METHODS

Twenty-five hospital- and population-based surveillance programs in 19 International Clearinghouse for Birth Defects Surveillance and Research member countries provided birth defects mortality data between 1974 and 2015. CDH cases included live births, stillbirths, or elective termination of pregnancy for fetal anomalies. Prevalence, cumulative mortality rates, and 95% confidence intervals (CIs) were calculated using Poisson regression and a Kaplan-Meier product-limit method. Joinpoint regression analyses were conducted to assess time trends.

RESULTS

The prevalence of CDH was 2.6 per 10,000 total births (95% CI: 2.5-2.7), slightly increasing between 2001 and 2012 (average annual percent change = 0.5%; 95% CI:-0.6 to 1.6). The total percent mortality of CDH was 37.7%, with hospital-based registries having more deaths among live births than population-based registries (45.1% vs. 33.8%). Mortality rates decreased over time (average annual percent change = -2.4%; 95% CI: -3.8 to 1.1). Most deaths due to CDH occurred among 2- to 6-day-old infants for both registry types (36.3%, hospital-based; 12.1%, population-based).

CONCLUSIONS

The mortality of CDH has decreased over time. Mortality remains high during the first week and varied by registry type.

High-frequency vs. conventional ventilation at the time of CDH repair is not associated with higher mortality and oxygen dependency: a retrospective cohort study

PURPOSE

The VICI-trial reported that in patients with congenital diaphragmatic hernia (CDH), mortality or bronchopulmonary dysplasia (BPD) were equivalent using conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation. The purpose of this study was to determine if the mode of ventilation at the time of CDH repair affected mortality or oxygen dependence at 28 days.

METHODS

We performed a retrospective cohort study of infants born wih CDH from 1991 to 2015. A generalized linear model was applied to the data using a propensity score analysis.

RESULTS

Eighty patients met the inclusion criteria; at the time of surgery 39 (48.8%) patients were on HFV and 41 (51.3%) patients were on CMV. In the HFV group, 16 (47.1%) patients remained oxygen dependent and there were 5 (12.8%) deaths at 28 days. In the CMV group, 5 (12.2%) patients remained oxygen dependent at 28 days but none had died. The base model demonstrated that the HFV group had increased rates of oxygen dependence [OR = 6.40 (2.13, 22.2), p = 0.002]. However, after propensity score analysis, we found no difference between HFV and CMV.

CONCLUSION

Our study suggests that in infants with CDH, there is no significant difference between HFV and CMV in oxygen dependency or death.

A single-center observational study on congenital diaphragmatic hernia: Outcome, predictors of mortality and experience from a tertiary perinatal center in Singapore

BACKGROUND

Congenital diaphragmatic hernia (CDH) is a common birth defect associated with significant mortality and morbidity. There is limited outcome data on CDH in the Southeast Asian region. Rapid accessibility to our CDH Perinatal Center, as a consequence of the small geographic size of our country and efficient land transportation system, has largely eliminated deaths of live outborn babies prior arrival at our center. We selected a study period when extracorporeal membrane oxygenation (ECMO) support was not available at our institution. The data will therefore be relevant in developing management guidelines and antenatal counselling for perinatal centers in this region managing CDH with limited resources, without ECMO facilities.

METHODS

A retrospective study of antenatally or postnatally diagnosed CDH infants born between January 2002 and June 2005 was performed. We selected this study period as ECMO support was not available over this period. We studied the demographics, clinical characteristics, postnatal predictors of mortality and outcomes of CDH infants in a single tertiary institution.

RESULTS

A total of 24 patients with CDH were identified. Seventy-nine percent of liveborns with CDH survived to hospital discharge. Antenatal detection rate was 83.3%. Significant postnatal predictors of mortality were preoperative pneumothorax (p = 0.035), high CRIB score (p = 0.007), low one- and five-minute Apgar score (p = 0.011, p = 0.026 respectively) and high pCO2 on initial arterial blood gas (p = 0.007). At one-year follow-up, three patients had delayed gross motor milestones which resolved subsequently. Re-admissions were required for recurrent bronchiolitis (33%) and oesophageal reflux which resolved in all cases. Two (13.3%) infants had surgical complications and needed re-admission for probable adhesive intestinal obstruction; one required adhesiolysis and the other was managed conservatively with good outcome.

CONCLUSION

A single-center CDH outcome in Singapore, without ECMO use, was good. This is a cohort now with long-term survival outcome which will be valuable to the neonatology community.

Overexpression of miR-455-5p affects retinol (vitamin A) absorption by downregulating STRA6 in a nitrofen-induced CDH with lung hypoplasia rat model

Lung hypoplasia is the main cause of congenital diaphragmatic hernia (CDH)-associated death but pathogenesis remains unclear. MiR-455-5p is involved in lung hypoplasia. We hypothesized that nitrofen causes abnormal miR-455-5p expression during lung development and designed this study to determine the relationship between miR-455-5p, stimulated by retinoic acid 6 (STRA6), and retinol in a nitrofen-induced CDH with lung hypoplasia rat model. Nitrofen or olive oil was administered to Sprague-Dawley rats by gavage on day 9.5 of gestation, and the rats were divided into a nitrofen group and a control group (n = 6). The left lung of fetuses was dissected on day 15.5. The expression of miR-455-5p or STRA6 messenger RNA (mRNA) was determined by quantitative real-time polymerase chain reaction. Average integrated optical density (IOD) of STRA6 protein was determined by immunofluorescence histochemistry. The average retinol level was detected by enzyme-linked immunosorbent assay (n = 6 lungs, respectively). Compared with the control group, the nitrofen group exhibited significantly increased miR-455-5p expression levels (29.450 ± 9.253 vs 5.955 ± 2.330; P = .00045) and significantly decreased STRA6 mRNA levels (0.197 ± 0.097 vs 0.588 ± 0.184; P = .0047). In addition, the average IOD of the STRA6 protein was significantly lower in the nitrofen group (805.643 ± 291.182 vs 1616.391 ± 572.308, P = .015), and the average retinol level was significantly reduced (4.013 ± 0.195 vs 5.317 ± 0.337 µg/L, P = .000). In summary, the overexpression of miR-455-5p affected retinol absorption by downregulating STRA6 in the nitrofen-induced CDH with lung hypoplasia rat model, and this downregulation may be one cause of CDH with lung hypoplasia.

Is laterality of congenital diaphragmatic hernia a reliable prognostic factor? French national cohort study

OBJECTIVES

The objective of this study was to assess whether the laterality of congenital diaphragmatic hernia (CDH) was a prognostic factor for neonatal survival.

METHODS

This was a cohort study using the French national database of the Reference Center for Diaphragmatic Hernias. The principal endpoint was survival after hospitalization in intensive care. We made a comparative study between right CDH and left CDH by univariate and multivariate analysis. Terminations and stillbirths were excluded from analyses of neonatal outcomes.

RESULTS

A total of 506 CDH were included with 67 (13%) right CDH and 439 left CDH (87%). Rate of survival was 49% for right CDH and 74% for left CDH (P < .01). Multivariate analysis showed two factors significantly associated with mortality: thoracic herniation of liver (OR 2.27; IC 95% [1.07-4.76]; P = .03) and lung-to-head-ratio over under expected (OR 2.99; IC 95% [1.41-6.36]; P < .01). Side of CDH was not significantly associated with mortality (OR 1.87; IC 95% [0.61-5.51], P = .26).

CONCLUSION

Rate of right CDH mortality is more important than left CDH. Nevertheless after adjusting for lung-to-head-ratio and thoracic herniation of liver, right CDH does not have a higher risk of mortality than left CDH.

Validation of a Prediction Rule for Mortality in Congenital Diaphragmatic Hernia

BACKGROUND

Congenital diaphragmatic hernia (CDH) is a rare congenital anomaly with a mortality of ∼27%. The Congenital Diaphragmatic Hernia Study Group (CDHSG) developed a simple postnatal clinical prediction rule to predict mortality in newborns with CDH. Our aim for this study is to externally validate the CDHSG rule in the European population and to improve its prediction of mortality by adding prenatal variables.

METHODS

We performed a European multicenter retrospective cohort study and included all newborns diagnosed with unilateral CDH who were born between 2008 and 2015. Newborns born from November 2011 onward were included for the external validation of the rule (n = 343). To improve the prediction rule, we included all patients born between 2008 and 2015 (n = 620) with prenatally diagnosed CDH and collected pre- and postnatal variables. We build a logistic regression model and performed bootstrap resampling and computed calibration plots.

RESULTS

With our validation data set, the CDHSG rule had an area under the curve of 79.0%, revealing a fair predictive performance. For the new prediction rule, prenatal herniation of the liver was added, and absent 5-minute Apgar score was taken out. The new prediction rule revealed good calibration, and with an area under the curve of 84.6%, it had good discriminative abilities.

CONCLUSIONS

In this study, we externally validated the CDHSG rule for the European population, which revealed fair predictive performance. The modified rule, with prenatal liver herniation as an additional variable, appears to further improve the model's ability to predict mortality in a population of patients with prenatally diagnosed CDH.

Prediction tools in congenital diaphragmatic hernia

Because congenital diaphragmatic hernia (CDH) is characterized by a spectrum of severity, risk stratification is an essential component of care. In both the prenatal and postnatal periods, accurate prediction of outcomes may inform clinical decision-making, care planning, and resource allocation. This review examines the history and utility of the most well-established risk prediction tools currently available, and provides recommendations for their optimal use in the management of CDH patients.

Safety of delayed decannulation of venoarterial cannulas in patients with congenital diaphragmatic hernia

BACKGROUND

The practice of "cutting-away" from venoarterial extracorporeal life support (ECLS) and leaving indwelling heparinized cannulas prior to decannulation is controversial. This study aims to determine the safety and efficacy of this strategy in patients with congenital diaphragmatic hernia (CDH) who require ECLS.

METHODS

A single-center retrospective review of electronic health records was performed on all patients with CDH who underwent elective ECLS decannulation between January 2014 and September 2018. Descriptive statistics are presented as medians with interquartile range.

RESULTS

Seventy-three percent (19/26) of patients who underwent venoarterial ECLS for CDH were electively decannulated. After a median ECLS run of 10.7 days [6.1-19.5], patients were "cut-away" for a median of 26 h [19.8-43] prior to decannulation. One patient required re-initiation at 36 h for a pulmonary hypertensive crisis (5%). There were no major bleeding or embolic events while "cut-away", and four (21%) patients had clots removed from the cannulas without clinical sequelae. One patient was recannulated 16 days following initial decannulation.

CONCLUSIONS

Our data suggests that "cutting-away" from ECLS in patients with congenital diaphragmatic hernia is safe and allows a period of observation without significant complications. This strategy may be particularly helpful in patients at risk for recannulation, but better prognostic criteria are needed.

LEVEL OF EVIDENCE

Level IV.

TYPE OF STUDY

Treatment Study.

Development and Validation of Extracorporeal Membrane Oxygenation Mortality-Risk Models for Congenital Diaphragmatic Hernia

The purpose of our study was to develop and validate extracorporeal membrane oxygenation (ECMO)–specific mortality risk models for congenital diaphragmatic hernia (CDH). We utilized the data from the Extracorporeal Life Support Organization Registry (2000–2015). Prediction models were developed using multivariable logistic regression. We identified 4,374 neonates with CDH with an overall mortality of 52%. Predictive discrimination (C statistic) for pre-ECMO mortality model was C = 0.65 (95% confidence interval, 0.62–0.68). Within the highest risk group, based on the pre-ECMO risk score, mortality was 87% and 75% in the training and validation data sets, respectively. The pre-ECMO risk score included pre-ECMO ventilator settings, pH, prior diaphragmatic hernia repair, critical congenital heart disease, perinatal infection, and demographics. For the on-ECMO model, mortality prediction improved substantially: C = 0.73 (95% confidence interval, 0.71–0.76) with the addition of on-ECMO–associated complications. Within the highest risk group, defined by the on-ECMO risk score, mortality was 90% and 86% in the training and validation data sets, respectively. Mortality among neonates with CDH needing ECMO can be reliably predicted with validated clinical variables identified in this study. ECMO-specific mortality prediction tools can allow risk stratification to be used in research and quality improvement efforts, as well as with caution for individual case management.

Congenital heart disease associated with congenital diaphragmatic hernia: A systematic review on incidence, prenatal diagnosis, management, and outcome

PURPOSE

The purpose of this study was to evaluate the impact of congenital heart disease (CHD) on infants with congenital diaphragmatic hernia (CDH).

METHODS

Using a defined search strategy (PubMed, Cochrane, Embase, Web of Science MeSH headings), we searched studies reporting the incidence, management, and outcome of CDH infants born with associated CHD.

RESULTS

Of 6410 abstracts, 117 met criteria. Overall, out of 28,974 babies with CDH, 4427 (15%) had CHD, of which 42% were critical. CDH repair was performed in a lower proportion of infants with CHD (72%) than in those without (85%; p < 0.0001). Compared to CDH babies without CHD, those born with a cardiac lesion were more likely to have a patch repair (45% vs. 30%; p < 0.01) and less likely to undergo minimally invasive surgery (5% vs. 17%; p < 0.0001). CDH babies with CHD had a lower survival rate than those without CHD (52 vs. 73%; p < 0.001). Survival was even lower (32%) in babies with critical CHD.

CONCLUSION

CHD has a strong impact on the management and outcome of infants with CDH. The combination of CDH and CHD results in lower survival than those without CHD or an isolated cardiac defect. Further studies are needed to address some specific aspects of the management of this fragile CDH cohort.

TYPE OF STUDY

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level III.

Comparison of early postnatal prediction models for survival in congenital diaphragmatic hernia

OBJECTIVE

To compare the PF-PCO₂ equation-partial pressure of arterial oxygen (PaO₂)/fraction of inspired oxygen (FiO₂) minus partial pressure of carbon dioxide (PCO₂)-to three other tools for postnatal prediction of survival in infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

A retrospective analysis of 203 infants with CDH from 1 January 2003 to 30 June 2018. Area under the curve (AUC) analysis was performed for survival and secondary outcomes of survival without extracorporeal membrane oxygenation support (ECMO) and death despite ECMO. Predictive scores were calculated to determine cutoff for PF-PCO₂ score.

RESULTS

The PF-PCO₂ tool had the highest AUC (0.84 for survival, 0.92 for survival without ECMO, and 0.83 for death despite ECMO). PF-PCO₂ best predicted survival when >-60 and survival without ECMO when >+80. There was no optimal cutoff score for death despite ECMO.

CONCLUSION

The PF-PCO₂ tool best predicted postnatal survival in infants with CDH.

Prenatal prediction of survival in congenital diaphragmatic hernia: An audit of postnatal outcomes

PURPOSE

Effective antenatal counseling in congenital diaphragmatic hernia (CDH) relies on proper measurement of prognostic indices. This quality initiative audited the accuracy of prenatal imaging with postnatal outcomes at two tertiary pediatric referral centers.

METHODS

Prenatal lung-head ratio (LHR) and total fetal lung volume (TFLV) for CDH patients treated between 2006 and 2017 were retrieved. Study inclusion required at least one LHR or TFLV measurement between 24 and 32 weeks gestational age. Postnatal outcomes [mortality, extracorporeal life support (ECLS) need, patch repair, persistent pulmonary hypertension, oxygen requirement at 28 days] were abstracted from the Canadian Pediatric Surgery Network (CAPSNet) database and local chart review. Univariate and descriptive analyses were conducted.

RESULTS

Eighty-two of 121 eligible CDH patients (68%) were included. Overall mortality, ECLS rates, and patch repair were 33%, 12.5%, and 45%, respectively. Lower LHR values correlated with increased rates of each outcome and persisted despite multiple measurements. Values obtained were higher than those in published schemata. LHR values >45% were most associated with survival, avoidance of ECLS, and primary repair. TFLV values only correlated with mortality and patch repair.

CONCLUSIONS

This audit confirms that LHR and TFLV values predict CDH outcomes. However, absolute values obtained require careful interpretation and internal review.

LEVEL OF EVIDENCE

IV.

One-year outcomes for congenital diaphragmatic hernia

Background

Congenital diaphragmatic hernia (CDH) is a congenital anomaly with high mortality and long‐term morbidity. The aim of this study was to benchmark trends in 1‐year and hospital volume outcomes for this condition.

Methods

This study included all infants born with CDH in England between 2003 and 2016. This was a retrospective analysis of the Hospital Episode Statistics database. The main outcomes were: 1‐year mortality, neonatal length of hospital stay (nLOS), total bed‐days at 1 year and readmission rate. The association between hospital volume and outcomes was assessed for specialist paediatric surgery centres.

Results

A total of 2336 infants were included (incidence 2·5 per 10 000 live births). No significant time trends were found in incidence and main outcomes. Some 1491 infants (63·8 per cent) underwent surgical repair. The 1‐year mortality rate was 31·2 per cent. Median nLOS and total bed‐days were 17 and 19 days respectively. The readmission rate in specialist paediatric centres was 6·3 per cent. Higher mortality was associated with birthweight lower than 1 kg (OR 5·90, 95 per cent c.i. 1·03 to 33·75), gestational age of 36 weeks or less (OR 1·75, 1·12 to 2·75) and black ethnicity (OR 2·13, 1·03 to 4·48). Only 4·0 per cent had extracorporeal membrane oxygenation, which was associated with higher mortality (OR 5·34, 3·01 to 9·46), longer nLOS (OR 3·70, 2·14 to 6·14) and longer total bed‐days (OR 3·87, 2·19 to 6·83). Specialist paediatric centres showed variation in 30‐day mortality (4·6 per cent with 84 per cent coefficient of variation), nLOS (median 25 (i.q.r. 15–42) days) and total bed‐days (median 28 (i.q.r. 16–51) days), but no significant volume–outcome relationship.

Conclusion

Key outcomes for CDH were similar to those of other developed countries. High variation among specialist paediatric centres was found and should be investigated further to explore the value of regionalization of care.

Application of a postnatal prediction model of survival in CDH in the era of fetal therapy

Background: The disease severity in patients with a congenital diaphragmatic hernia (CDH) is highly variable. To compare patient outcomes, set up clinical trials and come to severity-based treatment guidelines, a performant prediction tool early in neonatal life is needed.Objective: The primary purpose of this study was to validate the CDH study group (SG) prediction model for survival in neonates with CDH, including patients who had fetal therapy. Secondary, we aimed to assess its predictive value for early morbidity.Methods: This is a retrospective single-center study at the University Hospitals Leuven on all infants with a diagnosis of CDH live-born between April 2002 and December 2016. The prediction model of the CDHSG was applied to evaluate its performance in determining mortality risk. Besides, we examined its predictive value for early morbidity parameters, including duration of ventilation, respiratory support on day 30, time to full enteral feeding and length of hospital stay.Results: The CDHSG prediction model predicted survival well, with an area under the curve of 0.796 (CI: 0.720-0.871). It had poor value in predicting infants who needed respiratory support on day 30 (area under the curve (AUC) 0.606; CI: 0.493-0.719), and correlated poorly with duration of ventilation, time to full enteral feeding and length of hospital stay.Conclusion: The CDHSG prediction model was in our hands also a useful tool in predicting mortality in neonates with CDH in the fetal treatment era. Correlation with early morbidity was poor.RationaleObjectives: (1) Validation of the CDHSG prediction model for survival in a cohort of neonates with CDH, in whom fetal endoscopic tracheal occlusion was applied according to the severity of lung hypoplasia. (2) Evaluation of performance of the model in the prediction of early morbidity.Main results: (1) Confirmation of the predictive value of the model for survival in neonates with CDH in the era of fetal therapy. (2) No correlation of the model with early morbidity parameters.

Congenital diaphragmatic hernia repair in patients on extracorporeal membrane oxygenation: How early can we repair?

BACKGROUND

The benefits to early repair (<72 h postcannulation) of infants with congenital diaphragmatic hernia (CDH) on extracorporeal membrane oxygenation (ECMO) are increasingly recognized. Yet it is not known if even earlier repair (<24 h) results in comparable or improved patient outcomes. The goal of this study was to compare "super-early" (<24 h) to early repair (24-72 h) of CDH patients on ECMO.

METHODS

A retrospective review of infants with CDH placed on ECMO (2004-2017; n = 72) was performed. Data collected on the patients repaired while on ECMO within 72 h of cannulation (n = 33) included pre- and postnatal disease severity stratification variables and postnatal outcomes. Comparison groups were those patients repaired within 24 h of cannulation (n = 14) and those repaired between 24 and 72 h postcannulation (n = 19).

RESULTS

Patients undergoing "super-early" (<24 h) repair had an average survival of 71.4% compared to the average survival of 59.7% in the early repair group. Pre- and postnatal variables predicting disease severity were not significantly different between the groups. Mean hospital stays, ventilator days, and cannulation days were statistically similar between the groups.

CONCLUSIONS

Repair of patients with CDH patients on ECMO at less than 24 h postcannulation achieves outcomes that are comparable to those of repair between 24 and 72 h. While the present data suggest that there is not a "too early" time point for CDH repair on ECMO, larger multicenter studies are needed to validate our findings and determine the overall benefits.

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

Level III.

Pulmonary Hypertension in Patients with Congenital Diaphragmatic Hernia: Does Lung Size Matter?

PURPOSE

 The relationship between pulmonary hypoplasia and pulmonary arterial hypertension (PHTN) in patients with congenital diaphragmatic hernia (CDH) remains ill-defined. We hypothesized that prenatal estimates of lung size would directly correlate with PHTN severity.

METHODS

 Infants with isolated CDH (born 2004-2015) at a single institution were included. Estimates of lung size included observed-to-expected LHR (o:eLHR) and %-predicted lung volumes (PPLV = observed/predicted volumes). The primary outcome was severity of PHTN (grade 0-3) on echocardiography performed between day of life 3 and 30.

RESULTS

 Among 62 patients included, there was 32% mortality and 65% ECMO utilization. PPLV (odds ratio [OR] = 0.94 per 1 grade in PHTN severity, 95% confidence interval [CI] = 0.89-0.98, p < 0.01) and o:eLHR (OR = 0.97, 95% CI = 0.94-0.99, p < 0.01) were significantly associated with PHTN grade. Among patients on ECMO, PPLV (OR = 0.92, 95% CI = 0.84-0.99, p = 0.03) and o:eLHR (OR = 0.95, 95% CI = 0.92-0.99, p = 0.01) were more strongly associated with PHTN grade. PPLV and o:eLHR were significantly associated with the use of inhaled nitric oxide (iNO) (OR = 0.90, 95% CI = 0.83-0.98, p = 0.01 and OR = 0.94, 95% CI = 0.91-0.98, p < 0.01, respectively) and epoprostenol (OR = 0.91, 95% CI = 0.84-0.99, p = 0.02 and OR = 0.93, 95% CI = 0.89-0.98, p < 0.01, respectively).

CONCLUSION

 Among infants with isolated CDH, PPLV, and o:eLHR were significantly associated with PHTN severity, especially among patients requiring ECMO. Prenatal lung size may help predict postnatal PHTN and associated therapies.

Population-Based Validation of a Clinical Prediction Model for Congenital Diaphragmatic Hernias

OBJECTIVE

To examine the external validity of a well-known congenital diaphragmatic hernia (CDH) clinical prediction model using a population-based cohort.

STUDY DESIGN

Newborns with CDH born in California between 2007 and 2012 were extracted from the Vital Statistics and Patient Discharge Data Linked Files. The total CDH risk score was calculated according to the Congenital Diaphragmatic Hernia Study Group (CDHSG) model using 5 independent predictors: birth weight, 5-minute Apgar, pulmonary hypertension, major cardiac defects, and chromosomal anomalies. CDHSG model performance on our cohort was validated for discrimination and calibration.

RESULTS

A total of 705 newborns with CDH were extracted from 3 213 822 live births. Newborns with CDH were delivered in 150 different hospitals, whereas only 28 hospitals performed CDH repairs (1-85 repairs per hospital). The observed mortality for low-, intermediate-, and high-risk groups were 7.7%, 34.3%, and 54.7%, and predicted mortality for these groups were 4.0%, 23.2%, and 58.5%. The CDHSG model performed well within our cohort with a c-statistic of 0.741 and good calibration.

CONCLUSIONS

We successfully validated the CDHSG prediction model using an external population-based cohort of newborns with CDH in California. This cohort may be used to investigate hospital volume-outcome relationships and guide policy development.

Predicting Survival of Congenital Diaphragmatic Hernia on the First Day of Life

BACKGROUND

This study aimed to determine perinatal risk factors for 30-day mortality of congenital diaphragmatic hernia (CDH) patients and develop a prognostic index to predict 30-day mortality of CDH patients. Identifying risk factors that can prognosticate outcome is critical to obtain the best management practices for patients.

METHODS

A retrospective study was performed for patients who were diagnosed with CDH from November 2000 to August 2016. A total of 10 prenatal risk factors and 14 postnatal risk factors were analyzed. All postnatal variables were measured within 24 h after birth.

RESULTS

A total of 95 CDH patients were enrolled in this study, including 61 males and 34 females with mean gestational age of 38.86 ± 1.51 weeks. The overall 30-day survival rate was 63.2%. Multivariate analysis revealed that five factors (polyhydramnios, gestational age at diagnosis <25 weeks, observed-to-expected lung-to-head ratio ≤45, best oxygenation index in 24 h  >11, and severity of tricuspid regurgitation ≥ mild) were independent predictors of 30-day mortality of CDH. Using these five factors, a perinatal prognostic index for 30-day mortality was developed. Four predictive models (poor, bad, good, and excellent) of the perinatal prognostic index were constructed, and external validation was performed.

CONCLUSIONS

Awareness of risk factors is very important for predicting prognosis and managing patients. Five independent perinatal risk factors were identified in this study. A perinatal prognostic index was developed for 30-day mortality for patients with CDH. This index may be used to help manage CDH patients.

Pumpless arteriovenous extracorporeal membrane oxygenation: A novel mode of respiratory support in a lamb model of congenital diaphragmatic hernia

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is commonly required in neonates with congenital diaphragmatic hernia (CDH) complicated by pulmonary hypertension (PH). ECMO carries significant risk, and is contraindicated in the setting of extreme prematurity or intracranial hemorrhage. Pumpless arteriovenous ECMO (P-ECMO) may represent an alternative for respiratory support. The present study summarizes our initial experience with P-ECMO in a lamb model of CDH.

STUDY DESIGN

Surgical creation of CDH was performed at 65-75days' gestation. At term (135-145days), lambs were delivered into the P-ECMO circuit. Three animals were maintained on a low-heparin infusion protocol (target ACT 160-180) and three animals were maintained with no systemic heparinization.

RESULTS

Animals were supported by the circuit for 380.7 +/- 145.6h (range, 102-504h). Circuit flow rates ranged from 97 to 208ml/kg/min, with adequacy of organ perfusion demonstrated by stable serum lactate levels (3.0 +/- 1.7) and pH (7.4 +/- 0.3). Necropsy demonstrated no evidence of thrombogenic complications.

CONCLUSION

Pumpless extracorporeal membrane oxygenation achieved support of CDH model lambs for up to three weeks. This therapy has the potential to bridge neonates with decompensated respiratory failure to CDH repair with no requirement for systemic anticoagulation, and may be applicable to patients currently precluded from conventional ECMO support.

Isolated impact of liver herniation on outcome in fetuses with congenital diaphragmatic hernia - A matched-pair analysis based on fetal MRI relative lung volume

PURPOSE

To evaluate liver-herniation as individual parameter on outcome in children with congenital diaphragmatic hernia.

MATERIALS AND METHODS

In a retrospective matched-pair analysis based on observed to expected fetal lung volume (o/e FLV), birth weight, gestational age at time-point of examination, status of tracheal occlusion therapy and side of the defect the individual impact of liver-herniation on survival, need for extracorporeal membrane oxygenation (ECMO) therapy and chronic lung disease (CLD) was investigated. In total 61 pairs (122 patients) were included. Fisher's exact test was used to evaluate influence of liver-herniation and a p-value of <0.05 was defined as statistically significant. The study was approved by the local review board.

RESULTS

Children with liver-herniation have lower survival rates (78.7% vs. 95.1%; p = 0.0073), need ECMO-therapy more often (41.0% vs. 16.4%; p = 0.0027) and are more likely to develop CLD (71.7% vs. 37.9%; p = 0.0004) than their corresponding matched-pair without liver-herniation.

CONCLUSION

Liver-herniation itself and not further lung-volume restriction due to liver-herniation is responsible for poor outcome in CDH.

Health-related quality of life in children and adolescents with congenital diaphragmatic hernia: a cross-sectional study

BACKGROUND

Patients with congenital diaphragmatic hernia (CDH) have a high residual morbidity rate. We compared self-reported health-related quality of life (HRQoL) between patients with CDH and healthy children.

METHODS

Forty-five patients with CDH who were born from January 1, 1990, through February 15, 2015, were matched to healthy, age-matched control participants at a 1:2 ratio. The health records of the study participants were reviewed to determine comorbid conditions, and HRQoL was assessed by both the participants and their parents with the Pediatric Quality of Life Inventory (PedsQL). The HRQoL scores of the patients with CDH and the control participants were compared by using analysis of variance to adjust for age group and sex. Among patients with CDH, analysis of variance was used to compare HRQoL scores across groups defined according to their characteristics at initial hospitalization, postdischarge events, and comorbid conditions.

RESULTS

Compared with control participants, patients with CDH had lower mean PedsQL scores, as reported by the parent and child, for the physical and psychosocial domains (P < 0.001). Risk factors associated with lower parent-reported HRQoL included bronchopulmonary dysplasia, longer initial hospitalization, severe cognitive impairment, and orthopedic symptoms; among patients with CDH, low HRQoL was associated with chronic respiratory issues.

CONCLUSION

Patients with CDH had lower HRQoL compared with healthy participants. Parent-reported HRQoL tended to be higher than child-reported HRQoL. Results were also inconsistent for the risk factors associated with HRQoL obtained by using child- and parent-reported scores. Therefore, when interpreting HRQoL in CDH survivors, a proxy report should not be considered a substitute for a child's self-report.

One-Year Outcome for Congenital Diaphragmatic Hernia: Results From the French National Register

OBJECTIVE

To evaluate the status of congenital diaphragmatic hernia (CDH) management in France and to assess predictors of adverse outcomes.

STUDY DESIGN

We reviewed the first-year outcome of all cases of CDH reported to the French National Register in 2011.

RESULTS

A total of 158 cases were included. Of these, 83% (131) were prenatally diagnosed, with a mortality rate of 39% (44 of 112) for live born infants with a known outcome at hospital discharge. Mortality increased to 47% (60 of 128) including those with termination of pregnancy and fetal loss. This contrasts with the 7% (2 of 27) mortality rate of the patients diagnosed postnatally (P = .002). Mortality worsened with 1 prenatal marker of CDH severity (OR 3.38 [1.30-8.83] P = .013) and worsened further with 2 markers (OR 20.64 [5.29-80.62] P < .001). Classic postnatal risk factors of mortality such as side of hernia (nonleft P = .001), prematurity (P < .001), low birth weight (P = .002), and size of the defect (P < .001) were confirmed. Of the 141 live births (114 prenatal and 27 postnatal diagnosis) with known outcomes, 93 (67%) survived to hospital discharge, 68 (60%) with a prenatal diagnosis and 25 (93%) with a postnatal diagnosis. The median time to hospital discharge was 34 days (IQR, 19.25-62). Of these survivors, 71 (76%) were followed up for 1 year.

CONCLUSIONS

Despite advances in management of CDH, mortality was high and associated with prenatal risk factors. Postnatally, severe persistent pulmonary hypertension was difficult to predict and presented persistent challenges in management.