Ventricular Dysfunction Is a Critical Determinant of Mortality in Congenital Diaphragmatic Hernia

Ventricular Dysfunction in Patients With Congenital Diaphragmatic Hernia Who Die After Repair

BACKGROUND

Quantitative echocardiographic (echo) measures of ventricular function predict mortality in pediatric pulmonary hypertension (PH), but studies in congenital diaphragmatic hernia (CDH)-related PH are limited. Few studies report quantitative echo data beyond the first week of life in CDH non-survivors.

METHODS

A single-center retrospective, cross-sectional, cohort study included CDH patients born between January 2013 and April 2022 who survived to surgical repair but died during the neonatal hospitalization. Quantitative measures of right (RV) and left ventricular (LV) size and function including tricuspid annular plane systolic excursion Z-score (TAPSEZ), RV fractional area change (FAC), RV/LV ratio, LV eccentricity index, LV M-mode dimensions, and RV/LV systolic strain were performed offline on the last echocardiogram before death. Data were compared between patients who died ≤30 days after repair ("early") vs. >30 days after repair ("late") using the Wilcoxon rank sum test.

RESULTS

Twenty-five (11 early, 14 late) deceased patients had echo images available for analysis. LV size by end-diastolic dimension Z-score was smaller in patients who died early vs. late after repair [-3.03 (-3.93, -2.51) vs. -0.24 (-2.11, 0.53), p = 0.021]. There were trends toward worse RV function (TAPSEZ, RVFAC, RV global and free wall strain) and LV function (apical 4 chamber strain) in patients who died early vs. late after repair.

CONCLUSION

These preliminary findings support future study of the impact of ventricular hypoplasia and dysfunction on mortality and opportunities for risk stratification based on quantitative echo findings in CDH.

LEVEL OF EVIDENCE

Cohort study, 4.

Patterns and Outcomes of Epoprostenol Use in Infants with Congenital Diaphragmatic Hernia Requiring Extracorporeal Life Support

OBJECTIVE

To describe our experience utilizing epoprostenol for pulmonary hypertension (PH) in infants with congenital diaphragmatic hernia (CDH) requiring extracorporeal life support (ECLS).

STUDY DESIGN

We retrospectively reviewed infants diagnosed with CDH who required ECLS at our institution from 2013 to 2023. Data collected included demographics, disease characteristics, medication administration patterns, and hospital outcomes. We first compared infants who received intravenous epoprostenol and those who did not. Among infants who received epoprostenol, we compared survivors and nonsurvivors. χ² test/Fisher's exact and Mann-Whitney tests were used, with significance defined at P < .05.

RESULTS

Fifty-seven infants were included; 40 (70.2%) received epoprostenol. Infants receiving epoprostenol had lower observed/expected total fetal lung volume (O/E TFLV) on magnetic resonance imaging (20 vs 26.2%, P = .042) as well as higher prenatal frequency of liver-up (90 vs 64.7%, P = .023) and "severe" classification (67.5 vs 35.3%, P = .007). Survival with and without epoprostenol was comparable (60% vs 64%, P = .23). Of those receiving epoprostenol, both survivors and nonsurvivors had similar prenatal indicators of disease severity. Most (80%) of hernia defects were classified as type C/D and 68% were repaired <72 hours after ECLS cannulation. The median age at initiation of epoprostenol was day of life 6 (IQR: 4, 7) in survivors and 8 (IQR: 7, 16) in nonsurvivors (P = .012). Survivors had shorter ECLS duration (11 vs 20 days, P = .049). Of nonsurvivors, refractory PH was the cause of death for 13 infants (81%).

CONCLUSIONS

In infants with CDH requiring ECLS, addition of epoprostenol appears promising and earlier initiation may affect survival.

Congenital heart disease and arrhythmia disorders in newborns with congenital diaphragmatic hernia: a 23-year experience at a UK university pediatric surgical centre

PURPOSE

Congenital diaphragmatic hernia (CDH) is associated with congenital heart disease (CHD) and index newborns reportedly may experience cardiac arrhythmia disorders [Tella et al.-Pediatric Critical Care Medicine 2022]. This study analyses, details and reports contemporary outcome metrics of CHD and cardiac rhythm disease (CRD) in CDH babies attending a university surgical centre.

METHODS

Retrospective analysis of medical records of all newborns undergoing Bochdalek CDH repair between 1999 and 2021 at a university paediatric surgical centre. CDH newborns with CHD and neonatal arrythmias were identified from echocardiogram and electrocardiogram (ECG) investigative studies. Operative native diaphragm and / or use of patch repair(s) was documented. Outcome(s) measured-(i) mortality and (ii) cardiopulmonary interventions including ventilatory strategies-ECMO (%), inotropes and anti-arrhythmic therapy(s).

RESULTS

Of 173 CDH neonates, 95 (55%) had CHD of which 9 babies (10%) had cardiac arrhythmias. CDH and co-existing CHD was linked with (a) lower infant birth weights (3130 g vs 3357 g, p = 0.05), (b) increased use of inotrope agents (48.4% vs 39.3%, p = 0.03) and (c) greater use of high-frequency oscillatory ventilation (38.9% vs 23%, p = 0.004). CDH babies experiencing arrythmias were at higher risk (%) of developing pulmonary hypertension (66.7% vs 28.7%, p = 0.01). No significant differences were observed in ECMO utilisation (12% vs 6%, p = 0.46) or patch repair(s) (53% vs 46%, p = 0.06) in CDH patients with and without CHD. CHD was not associated with increased risk(s) of mortality (OR 2.58, 95% CI 0.81-8.24, p = 0.11). Of 9 index CDH patients with arrhythmias-4 babies (44%) required interventional treatments.

CONCLUSION

CHD was prevalent in a high percentage (%) of CDH newborns treated at this university centre and associated with increased use (%) of cardiovascular respiratory support including patch repair. A minority of patients (2.3%) had cardiac rhythm disorders requiring treatment(s). In those developing arrhythmias pulmonary hypertension may be a risk-linked event. Optimising outcomes to offset pulmonary hypertension requires further appraisal. Future large-scale population studies may help underscore the 'real apparent incidence' of cardiac rhythm disorders in CDH.

Echocardiographic Changes in Infants with Severe Congenital Diaphragmatic Hernia After Fetoscopic Endoluminal Tracheal Occlusion (FETO)

Fetoscopic endoluminal tracheal occlusion (FETO) induces lung growth and may improve survival in congenital diaphragmatic hernia (CDH) but the effect on post-natal right (RV) and left (LV) ventricular size and cardiac function is unknown. Quantitative measures of heart size and function including tricuspid annular plane systolic excursion Z-score (TAPSEZ), RV fractional area change (RVFAC), RV global longitudinal and free wall strain (RVGLS, RVFWS), RV/LV ratio, LV eccentricity index (LVEI), and LV M-mode diastolic and systolic Z-scores (LVIDDZ, LVIDSZ) were compared between FETO and control patients on first post-natal echocardiogram, prior to and post CDH repair, and on last available echocardiogram using non-parametric Wilcoxon rank-sum test in a single-center, retrospective cohort study. Linear regression models evaluated change over time, adjusting for clustering and interaction of echocardiogram parameters with time. Thirty-two patients (10 FETO, 22 control) met inclusion criteria. At first echocardiogram, FETO patients demonstrated lower RV/LV ratio and LVEI (p = 0.01 for both) indicating less RV dilation and less ventricular septal displacement, respectively. LV hypoplasia was less severe in FETO patients (p = 0.01 for both LVIDDZ and LVIDSZ) initially. After repair, FETO patients demonstrated better RV systolic function compared to control patients by FAC (p < 0.01), RVGLS (p = 0.02), and RVFWS (p = 0.05). Over time, FETO patients demonstrated greater improvements in RV/LV ratio and LVEI but smaller increases in LV dimensions compared to control patients. Improvements in RV function were similar between the groups. FETO patients demonstrate differences in cardiac size and function compared to control patients.

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.

Could a Two-Staged Repair Be the Solution to the Dilemma of Repair Timing for Severe Congenital Diaphragmatic Hernia Requiring Extracorporeal Membrane Oxygenation?

PURPOSE OF REVIEW

Congenital diaphragmatic hernia (CDH) remains a significant challenge, particularly in severe cases with persistent pulmonary hypertension (PPHN) and hypoplastic lungs and heart. For patients unresponsive to conventional therapies, ECMO is required. While the surgical repair is relatively simple, determining the optimal timing for surgery in patients requiring ECMO is particularly challenging. This review explores the dilemma of surgical timing and proposes a two-staged approach: a reduction in herniated organs and the creation of a silo to relieve abdominal pressure before initiating ECMO, with defect closure following ECMO decannulation.

RECENT FINDINGS

Studies support pre-, on-, and post-ECMO repair, each with its own risks and benefits. Pre-ECMO repair may enhance ECMO efficacy by relieving organ compression but poses risks due to instability. Post-ECMO repair is safer but may result in losing the chance to repair. On-ECMO repair has significant hemorrhage risks, but early repair with careful anticoagulation management is currently recommended. Recently, the author reported a successful case using a two-staged approach-reducing herniated organs and creating a silo before ECMO, followed by defect closure after ECMO decannulation-which suggests a potential alternative strategy for managing severe CDH.

SUMMARY

A two-staged approach may offer a solution for severe CDH patients requiring ECMO.

Feasibility of automated measurement of fetal right ventricular modified myocardial performance index with development of reference values and clinical application

To establish normal reference ranges for fetal right ventricular modified myocardial performance index (RV Mod-MPI) using automatic synchronization of the RV inflow and outflow images (MPI+TM). Additionally, we aimed to clinically apply RV Mod-MPI to investigate its changes in fetal right congenital diaphragmatic hernia (CDH) compared to normal fetuses. This prospective study included uncomplicated singleton pregnancies between 16 and 38 weeks of gestational age. Cases with any maternal or fetal complications that developed during the enrollment period were excluded. Two experienced operators measured the RV Mod-MPI using the automated and manual methods. The intraclass correlation coefficients (ICC) were calculated for intra- and inter-operator reproducibility. The mean differences between the manual and automated measurements were also compared. The RV Mod-MPI was then compared between the right CDH fetuses and normal fetuses. Seventy normal fetuses were analyzed for the feasibility of an automated system, and 364 examinations from 272 fetuses were analyzed for developing the normal references. The automated system showed significantly higher intra- and inter-operator reproducibility of Mod-MPI than those of manual measurements (ICC = 0.962 vs. 0.913 and 0.961 vs. 0.889, respectively). The mean difference in Mod-MPI between the manual and automated method was 0.0002 ± 0.0586 with a 95% confidence interval of -0.0095-0.0099. The Mod-MPI and isovolumetric relaxation time increased throughout the gestational weeks. The isovolumetric contraction time increased until 24 weeks of gestation and then slightly decreased afterwards, and the ejection time also increased until 31 weeks of gestation and then decreased. There was no significant difference in the Mod-MPI between right CDH and normal fetuses. The automated system showed high inter- and intra-operator reproducibility. Furthermore, the normal reference values of Mod-MPI for each gestational age were established. Our results suggest that the automated system might be clinically feasible for evaluating fetal cardiac function.

Neonatal high-frequency oscillatory ventilation: where are we now?

High-frequency oscillatory ventilation (HFOV) is an established mode of respiratory support in the neonatal intensive care unit. Large clinical trial data is based on first intention use in preterm infants with acute respiratory distress syndrome. Clinical practice has evolved from this narrow population. HFOV is most often reserved for term and preterm infants with severe, and often complex, respiratory failure not responding to conventional modalities of respiratory support. Thus, optimal, and safe, application of HFOV requires the clinician to adapt mean airway pressure, frequency, inspiratory:expiratory ratio and tidal volume to individual patient needs based on pathophysiology, lung volume state and infant size. This narrative review summarises the status of HFOV in neonatal intensive care units today, the lessons that can be learnt from the past, how to apply HFOV in different neonatal populations and conditions and highlights potential new advances. Specifically, we provide guidance on how to apply an open lung approach to mean airway pressure, selecting the correct frequency and use of volume-targeted HFOV.

The role of ECLS in the management of congenital diaphragmatic hernia

In the complex arena of Congenital Diaphragmatic Hernia (CDH) management, Extracorporeal Life Support (ECLS) provides a strategic window for stabilization and surgical correction, during which time marginal gains in patient stability can tip the scales towards survival. In modern neonatal ECLS, the focus is increasingly on minimizing survivor morbidity, which calls for considerable multidisciplinary expertise to enhance patient outcomes. This review will delve into the most up-to-date literature on the management of CDH in the context of ECLS, providing a comprehensive synthesis of current insights.

Congenital diaphragmatic hernia-associated pulmonary hypertension

Congenital diaphragmatic hernia (CDH) is characterized by a developmental insult which compromises cardiopulmonary embryology and results in a diaphragmatic defect, allowing abdominal organs to herniate into the hemithorax. Among the significant pathophysiologic components of this condition is pulmonary hypertension (PH), alongside pulmonary hypoplasia and cardiac dysfunction. Fetal pulmonary vascular development coincides with lung development, with the pulmonary vasculature evolving alongside lung maturation. However, in CDH, this embryologic development is impaired which, in conjunction with external compression, stifle pulmonary vascular maturation, leading to reduced lung density, increased muscularization of the pulmonary vasculature, abnormal vascular responsiveness, and altered molecular signaling, all contributing to pulmonary arterial hypertension. Understanding CDH-associated PH (CDH-PH) is crucial for development of novel approaches and effective management due to its significant impact on morbidity and mortality. Antenatal and postnatal diagnostic methods aid in CDH risk stratification and, specifically, pulmonary hypertension, including fetal imaging and gas exchange assessments. Management strategies include lung protective ventilation, fluid optimization, pharmacotherapies including pulmonary vasodilators and hemodynamic support, and extracorporeal life support (ECLS) for refractory cases. Longitudinal re-evaluation is an important consideration due to the complexity and dynamic nature of CDH cardiopulmonary physiology. Emerging therapies such as fetal endoscopic tracheal occlusion and pharmacological interventions targeting key CDH pathophysiological mechanisms show promise but require further investigation. The complexity of CDH-PH underscores the importance of a multidisciplinary approach for optimal patient care and improved outcomes.

Cardiac function in congenital diaphragmatic hernia

Cardiac function is known to play critical role in the pathophysiological progression and ultimate clinical outcome of patients with congenital diaphragmatic hernia (CDH). While often anatomically normal, the fetal and neonatal heart in CDH can suffer from both right and left ventricular dysfunction. Here we explore the abnormal fetal heart, early postnatal right and left ventricular dysfunction, the interplay between cardiac dysfunction and pulmonary hypertension, evaluation and echocardiographic assessment of the heart, and therapeutic strategies for managing and supporting the pathophysiologic heart and CDH. Further, we take a common clinical scenario and provide clinically relevant guidance for the diagnosis and management of this complex process.

Congenital Diaphragmatic Hernia Patients with Left Heart Hypoplasia and Left Ventricular Dysfunction Have Highest Odds of Mortality

OBJECTIVES

To describe the scope of left ventricular (LV) dysfunction and left heart hypoplasia (LHH) in infants with congenital diaphragmatic hernia (CDH), to determine associations with CDH severity, and to evaluate the odds of extracorporeal membrane oxygenation (ECMO) and death with categories of left heart disease.

STUDY DESIGN

Demographic and clinical variables were collected from a single-center, retrospective cohort of patients with CDH from January 2017 through May 2022. Quantitative measures of LV function and LHH were prospectively performed on initial echocardiograms. LHH was defined as ≥2 of the following: z score ≤ -2 of any left heart structure or LV end-diastolic volume <3 mL. LV dysfunction was defined as shortening fraction <28%, ejection fraction <60%, or global longitudinal strain <20%. The exposure was operationalized as a 4-group categorical variable (LV dysfunction +/-, LHH +/-). Logistic regression models evaluated associations with ECMO and death, adjusting for CDH severity.

RESULTS

One hundred eight-two patients (80.8% left CDH, 63.2% liver herniation, 23.6% ECMO, 12.1% mortality) were included. Twenty percent demonstrated normal LV function and no LHH (LV dysfunction-/LHH-), 37% normal LV function with LHH (LV dysfunction-/LHH+), 14% LV dysfunction without LHH (LV dysfunction+/LHH-), and 28% both LV dysfunction and LHH (LV dysfunction+/LHH+). There was a dose-response effect between increasing severity of left heart disease, ECMO use, and mortality. LV dysfunction+/LHH + infants had the highest odds of ECMO use and death, after adjustment for CDH severity [OR (95% CI); 1.76 (1.20, 2.62) for ECMO, 2.76 (1.63, 5.17) for death].

CONCLUSIONS

In our large single-center cohort, patients with CDH with LV dysfunction+/LHH + had the highest risk of ECMO use and death.

Arterial hypertension in infants with congenital diaphragmatic hernia following surgical repair

Pulmonary hypertension (PH) and cardiac dysfunction are established comorbidities of congenital diaphragmatic hernia (CDH). However, there is very little data focusing on arterial hypertension in CDH. This study aims to investigate the incidence of arterial hypertension in neonates with CDH at hospital discharge. Archived clinical data of 167 CDH infants who received surgical repair of the diaphragmatic defect and survived for > 60 days were retrospectively analyzed. Blood pressure (BP) values were averaged for the last 7 days before discharge and compared to standard BP values for sex, age, and height provided by the AHA in 2004. BP values reaching or extending the 95th percentile were defined as arterial hypertension. The use of antihypertensive medication was analyzed at discharge and during hospitalization. Arterial hypertension at discharge was observed in 19 of 167 infants (11.3%) of which 12 (63%) were not receiving antihypertensive medication. Eighty patients (47.9%) received antihypertensive medication at any point during hospitalization and 28.9% of 152 survivors (n = 44) received antihypertensive medication at discharge, although in 45.5% (n = 20) of patients receiving antihypertensive medication, the indication for antihypertensive medication was myocardial hypertrophy or frequency control. BP was significantly higher in ECMO compared to non-ECMO patients, despite a similar incidence of arterial hypertension in both groups (13.8% vs. 10.1%, p = 0.473). Non-isolated CDH, formula feeding, and minimal creatinine in the first week of life were significantly associated with arterial hypertension on univariate analysis. Following multivariate analysis, only minimal creatinine remained independently associated with arterial hypertension.   Conclusion: This study demonstrates a moderately high incidence of arterial hypertension in CDH infants at discharge and an independent association of creatinine values with arterial hypertension. Physicians should be aware of this risk and include regular BP measurements and test of renal function in CDH care and follow-up. What is Known: • Due to decreasing mortality, morbidity is increasing in surviving CDH patients. • Pulmonary hypertension and cardiac dysfunction are well-known cardiovascular comorbidities of CDH. What is New: • There is a moderately high incidence of arterial hypertension in CDH infants at discharge even in a population with frequent treatment with antihypertensive medication. • A more complicated hospital course (ECMO, higher degree of PH, larger defect size) was associated with a higher risk for arterial hypertension.

Left atrial strain in neonates with congenital diaphragmatic hernia and length of stay in pediatric intensive care unit

Introduction

The role of cardiac left ventricle (LV) dysfunction in children with congenital diaphragmatic hernia (CDH) has gained increasing attention. The hernia allows abdominal mass to enter thorax and subsequently both dislocating and compressing the heart. The pressure on vessels and myocardium alters blood flow and may interfere with normal development of the LV. A dysfunctional LV is concerning and impacts the complex pathophysiology of CDH. Hence, assessing both the systolic and diastolic LV function in the newborn with CDH is important, and it may add value for medical treatment and prognostic factors as length of stay (LOS) in pediatric intensive care unit (PICU). LV strain is considered an early marker of systolic dysfunction used in the pediatric population. Left atrial (LA) strain is an echocardiographic marker of LV diastolic dysfunction used in the adult population. When filling pressure of the LV increases, the strain of the atrial wall is decreased. We hypothesized that reduced LA strain and LV strain are correlated with the LOS in the PICU of newborns with CDH.

Methods

This retrospective observational cohort study included data of 55 children born with CDH between 2018 and 2020 and treated at Karolinska University Hospital, Sweden. Overall, 46 parents provided consent. Echocardiograms were performed in 35 children <72 h after birth. The LA reservoir strain (LASr), LV global longitudinal strain, LV dimensions, and direction of blood flow through the patent foramen ovale (PFO) were retrospectively assessed using the echocardiograms.

Results

Children with LASr <33% (n = 27) had longer stays in the PICU than children with LA strain ≥33% (n = 8) (mean: 20.8 vs. 8.6 days; p < 0.002). The LASr was correlated with the LOS in the PICU (correlation coefficient: -0.378; p = 0.025). The LV dimension was correlated with the LOS (correlation coefficient: -0.546; p = 0.01). However, LV strain was not correlated to LOS.

Conclusion

Newborns with CDH and a lower LASr (<33%) had longer stays in the PICU than children with LASr ≥33%. LASr is a feasible echocardiographic marker of diastolic LV dysfunction in newborns with CDH and may indicate the severity of the condition.

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.

Hemodynamic management of congenital diaphragmatic hernia: the role of targeted neonatal echocardiography

Congenital diaphragmatic hernia (CDH) is a major congenital anomaly, resulting from the herniation of abdominal contents into the thoracic cavity, thereby impeding the proper development of the lungs and pulmonary vasculature. CDH severity correlates with a spectrum of pulmonary hypoplasia, pulmonary hypertension (PHT), and cardiac dysfunction, constituting the pathophysiological triad of this complex condition. The accurate diagnosis and effective management of PHT and cardiac dysfunction is pivotal to optimizing patient outcomes. Targeted neonatal echocardiography is instrumental in delivering real-time data crucial for the bespoke, pathophysiology-targeted hemodynamic management of CDH-associated PHT.

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.

"Heart of the Matter": Cardiac Dysfunction in Congenital Diaphragmatic Hernia

Despite advances in caring for neonates with congenital diaphragmatic hernia (CDH), mortality and morbidity continues to be high. Additionally, the pathophysiology of cardiac dysfunction in this condition is poorly understood. Postnatal cardiac dysfunction in neonates with CDH may be multifactorial with origins in fetal life. Mechanical obstruction, competition from herniated abdominal organs into thoracic cavity combined with redirection of ductus venosus flow away from patent foramen ovale leading to smaller left-sided structures may be a contributing factor. This shunting decreases left atrial and left ventricular blood volume, which may result in altered micro- and macrovascular aberrations affecting cardiac development in the prenatal period. Direct mass effect from herniated intra-abdominal contents restricting cardiac growth and/or reduced left ventricular preload may contribute independently to left ventricular dysfunction in the absence of right ventricular dysfunction and or pulmonary hypertension. With variable clinical phenotypes of cardiac dysfunction, pulmonary hypertension, and respiratory failure in patients with CDH, there is increased need for individualized diagnosis and tailored therapy. Routine use of therapy such as inhaled nitric oxide and sildenafil that induces significant pulmonary vasodilation may be detrimental in left ventricle dysfunction, whereas in a patient with pure right ventricle dysfunction, they may be beneficial. Targeted functional echocardiography serves as a real-time tool for defining the pathophysiology and aids optimization of vasoactive therapy in affected neonates. KEY POINTS: · Cardiac dysfunction in neonates with CDH is multifactorial.. · Postnatal cardiac dysfunction in patients with CDH has its origins in fetal life.. · Right ventricular dysfunction contributes to systemic hypotension.. · Left ventricular dysfunction contributes to systemic hypotension.. · Supportive therapy should be tailored to clinical phenotype..

Diagnosis and management of congenital diaphragmatic hernia: a 2023 update from the Canadian Congenital Diaphragmatic Hernia Collaborative

OBJECTIVE

The Canadian Congenital Diaphragmatic Hernia (CDH) Collaborative sought to make its existing clinical practice guideline, published in 2018, into a 'living document'.

DESIGN AND MAIN OUTCOME MEASURES

Critical appraisal of CDH literature adhering to Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Evidence accumulated between 1 January 2017 and 30 August 2022 was analysed to inform changes to existing or the development of new CDH care recommendations. Strength of consensus was also determined using a modified Delphi process among national experts in the field.

RESULTS

Of the 3868 articles retrieved in our search that covered the 15 areas of CDH care, 459 underwent full-text review. Ultimately, 103 articles were used to inform 20 changes to existing recommendations, which included aspects related to prenatal diagnosis, echocardiographic evaluation, pulmonary hypertension management, surgical readiness criteria, the type of surgical repair and long-term health surveillance. Fifteen new CDH care recommendations were also created using this evidence, with most related to the management of pain and the provision of analgesia and neuromuscular blockade for patients with CDH.

CONCLUSIONS

The 2023 Canadian CDH Collaborative's clinical practice guideline update provides a management framework for infants and children with CDH based on the best available evidence and expert consensus.

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.

[Characteristics and Outcome of Neonates With Postnatally Diagnosed Congenital Diaphragmatic Hernia]

INTRODUCTION

Congenital diaphragmatic hernia (CDH) is one of the most severe neonatal malformations with a mortality of 20-35%. Currently, the rate of prenatally recognized CDHs is 60-80%. This study investigated the characteristics and outcome data of children with prenatally unrecognized CDH.

METHODS

Postnatally diagnosed CDH newborns treated at the University Hospital Bonn between 2012 and 2021 were included. Treatment and outcome data were compared according to type of maternity hospital, Apgar values, and between prenatally and postnatally diagnosed CDH.

RESULTS

Of 244 CDH newborns, 22 were included. Comparison for birth in a facility with vs. without pediatric care showed for mortality: 9% vs. 27%, p=0.478; ECMO rate: 9% vs. 36%, p=0.300; age at diagnosis: 84 vs. 129 min, p=0.049; time between intubation and diagnosis: 20 vs. 86 min, p=0.019. Newborns in the second group showed significantly worse values for pH and pCO2. Furthermore, there was a tendency for higher mortality and ECMO rates in children with an Apgar score<7 vs.≥7. Children diagnosed postnatally were significantly more likely to have moderate or severe PH and tended to have cardiac dysfunction more often than those diagnosed prenatally.

DISCUSSION

In our cohort, ca. one in 10 newborns received a postnatal CDH diagnosis. Birth in a facility without pediatric care is associated with later diagnosis, which may favor hypercapnia/acidosis and more severe pulm.

HYPERTENSION

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.

Targeted Neonatal Echocardiography in the Management of Neonatal Pulmonary Hypertension

Pulmonary hypertension (PH) in neonates, originating from a range of disease states with heterogeneous underlying pathophysiology, is associated with significant morbidity and mortality. Although the final common pathway is a state of high right ventricular afterload leading to compromised cardiac output, multiple hemodynamic phenotypes exist in acute and chronic PH, for which cardiorespiratory treatment strategies differ. Comprehensive appraisal of pulmonary pressure, pulmonary vascular resistance, cardiac function, pulmonary and systemic blood flow, and extrapulmonary shunts facilitates delivery of individualized cardiovascular therapies in affected newborns.

Mechanical ventilation in special populations

Optimal respiratory support can only be achieved if the ventilator strategy utilized for each individual patient at any given point in the evolution of their disease process is tailored to the underlying pathophysiology. The critically ill newborn infant requires individualized patient care when it comes to mechanical ventilation. This can only occur if the clinician has a good understanding of the different pathophysiologies of a variety of conditions that can lead to respiratory failure. In this chapter we describe the key pathophysiological features of bronchopulmonary dysplasia, meconium aspiration syndrome and lung hypoplasia syndromes with emphasis on congenital diaphragmatic hernia. We review available evidence to guide management an provide specific recommendations for pathophysiologically-based mechanical ventilation support.

The role of point-of-care ultrasound in the management of neonates with congenital diaphragmatic hernia

In the last few years, current evidence has supported the use of point-of-care ultrasound (POCUS) for a number of diagnostic and procedural applications. Considering the valuable information that POCUS can give, we propose a standardized protocol for the management of neonates with a congenital diaphragmatic hernia (CDH-POCUS protocol) in the neonatal intensive care unit. Indeed, POCUS could be a valid tool for the neonatologist through the evaluation of 1) cardiac function and pulmonary hypertension; 2) lung volumes, postoperative pleural effusion or pneumothorax; 3) splanchnic and renal perfusion, malrotations, and/or signs of necrotizing enterocolitis; 4) cerebral perfusion and eventual brain lesions that could contribute to neurodevelopmental impairment. In this article, we discuss the state-of-the-art in neonatal POCUS for which concerns congenital diaphragmatic hernia (CDH), and we provide suggestions to improve its use. IMPACT: This review shows how point-of-care ultrasound (POCUS) could be a valid tool for managing neonates with congenital diaphragmatic hernia (CDH) after birth. Our manuscript underscores the importance of standardized protocols in neonates with CDH. Beyond the well-known role of echocardiography, ultrasound of lungs, splanchnic organs, and brain can be useful. The use of POCUS should be encouraged to improve ventilation strategies, systemic perfusion, and enteral feeding, and to intercept any early signs related to future neurodevelopmental impairment.

A comparative analysis of the Vasoactive-Inotropic Score, the Vasoactive-Ventilation-Renal Score, and the Oxygenation Index as outcome predictors in infants with a congenital diaphragmatic hernia

OBJECTIVES

To date, different severity scores and indices are available to predict outcome in infants with a congenital diaphragmatic hernia (CDH). The Oxygenation Index (OI) and the Vasoactive-Inotropic Score (VIS) has already been evaluated in the CDH population. The Vasoactive-Ventilation-Renal (VVR) Score was recently evaluated as new severity score in several studies on infants with need for cardiac surgery. The score was shown to outperform the VIS and OI as outcome predictors in these infants, but no data are available regarding the evaluation of the VVR Score in CDH infants.

PATIENTS AND METHODS

This was a retrospective single-center analysis at the University Children's Hospital, Bonn, Germany, during the study period from January 2019 until December 2022. Of 108 CDH infants treated at our institution, a final cohort of 100 neonates met the inclusion criteria.

INCLUSION CRITERIA

diagnosis of CDH (right-sided, left-sided, or bilateral).

EXCLUSION CRITERIA

early mortality (before surgical correction of the diaphragm), palliative care after birth, no available data for OI, VIS, and VVR Score calculation. The OI, the VIS, and the VVR Score were calculated at three selected timepoints: at 48-72 h after birth (T1), before surgery (T2), and after surgery (T3).

MAIN RESULTS

The primary clinical endpoint (in-hospital mortality) was reached in 21% of the infants. Infants surviving to discharge were allocated to group A, infants with fatal outcome to group B. In the univariate analysis, the OI was significantly higher in infants allocated to group B at T2 (p < .001), and T3 (p < .001). The VIS was significantly higher only at T1 in infants allocated to group B (p = .001). The VVR Score was significantly higher at T1 (p = .017), and at T3 (p = .002) in infants not surviving to discharge. In the multivariate analysis, the OI at T2 + T3 (p < .001), the VIS at T1 (p = .048), and the VVR Score at T1 + T3 (p = .023, and p = .048, respectively) remained significantly associated with in-hospital mortality. The OI presented the highest area under the curve (AUC) at T2 and T3 (T2:0.867, p = .001; T3:0.833, p = .000) regarding the primary endpoint in the overall cohort. In the subgroup of infants without need for extracorporeal membrane oxygenation (ECMO) therapy (n = 60) the VVR Sore presented the best performance with an AUC of 0.942 (p = .000) at T3.

CONCLUSION

The severity scores OI, VIS, and VVR-Score are independent predictors of in-hospital mortality in CDH infants. The OI seems to outperform the VIS and VVR-Score as outcome predictor immediately before and after CDH surgery, whereas the VVR Score presented the best performance in the subgroup of CDH infants without need for ECMO and mild-to-moderate CDH defects.

Congenital Diaphragmatic Hernia: Pulmonary Hypertension and Pulmonary Vascular Disease

This review provides a comprehensive summary of the current understanding of pulmonary hypertension (PH) in congenital diaphragmatic hernia, outlining the underlying pathophysiologic mechanisms, methods for assessing PH severity, optimal management strategies, and prognostic implications.

Spontaneous breathing in selected neonates with very mild congenital diaphragmatic hernia

AIMS

Current treatment guidelines recommend immediate postnatal intubation in all neonates with congenital diaphragmatic hernia (CDH). This study aimed to investigate the feasibility and outcomes of a spontaneous breathing approach (SBA) versus immediate intubation in neonates with prenatally diagnosed very mild CDH.

METHODS

A retrospective study was conducted comparing neonates with very mild CDH (left-sided, liver-down, observed-to-expected lung-to-head ratio ≥45%) undergoing SBA and matched controls receiving standard treatment. Data on early echocardiographic findings, respiratory support, length of hospital stay, and clinical outcomes were analyzed.

RESULTS

Of 151 CDH neonates, eight underwent SBA, while 31 received standard treatment. SBA was successful in six of eight patients. SBA patients had shorter length of stay (14 vs. 30 days, p = .005), mechanical ventilation (3.5 vs. 8.7 days, p = .011), and oxygen supplementation (3.2 vs. 9.3 days, p = .013) compared to matched controls. Echocardiographic evidence of pulmonary hypertension and cardiac dysfunction were significantly lower in SBA neonates after admission but similar before surgical repair. The SBA group tolerated enteral feeding earlier (day of life 7 vs. 16, p = .019).

CONCLUSIONS

SBA appears feasible and beneficial for prenatally diagnosed very mild CDH. It was associated with a shortened hospital stay supportive therapies. However, larger trials are needed to confirm these findings and determine optimal respiratory support.

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

To evaluate the effectiveness of a novel protocol, adopted in our institution, as a quality improvement project for congenital diaphragmatic hernia (CDH). A maximal lung protection (MLP) protocol was implemented in 2019. This strategy included immediate use of high-frequency oscillatory ventilation (HFOV) after birth, during the stay at the Neonatal Intensive Care Unit (NICU), and during surgical repair. HFOV strategy included low distending pressures and higher frequencies (15 Hz) with subsequent lower tidal volumes. Surgical repair was performed early, within 24 h of birth, if possible. A retrospective study of all inborn neonates prenatally diagnosed with CDH and without major associated anomalies was performed at the NICU of Schneider Children's Medical Center of Israel between 2009 and 2022. Survival rates and pulmonary outcomes of neonates managed with MLP were compared to the historical standard care cohort. Thirty-three neonates were managed with the MLP protocol vs. 39 neonates that were not. Major adverse outcomes decreased including death rate from 46 to 18% (p = 0.012), extracorporeal membrane oxygenation from 39 to 0% (p < 0.001), and pneumothorax from 18 to 0% (p = 0.013).

CONCLUSION

 MLP with early surgery significantly improved survival and additional adverse outcomes of neonates with CDH. Prospective randomized studies are necessary to confirm the findings of the current study.

WHAT IS KNOWN

• Ventilator-induced lung injury was reported as the main cause of mortality in neonates with congenital diaphragmatic hernia (CDH). • Conventional ventilation is recommended by the European CDH consortium as the first-line ventilation modality; timing of surgery is controversial.

WHAT IS NEW

• A maximal lung protection strategy based on 15-Hz high-frequency oscillatory ventilation with low distending pressures as initial modality and early surgery significantly reduced mortality and other outcomes.

Guidelines and Recommendations for Targeted Neonatal Echocardiography and Cardiac Point-of-Care Ultrasound in the Neonatal Intensive Care Unit: An Update from the American Society of Echocardiography

Targeted neonatal echocardiography (TNE) involves the use of comprehensive echocardiography to appraise cardiovascular physiology and neonatal hemodynamics to enhance diagnostic and therapeutic precision in the neonatal intensive care unit. Since the last publication of guidelines for TNE in 2011, the field has matured through the development of formalized neonatal hemodynamics fellowships, clinical programs, and the expansion of scientific knowledge to further enhance clinical care. The most common indications for TNE include adjudication of hemodynamic significance of a patent ductus arteriosus, evaluation of acute and chronic pulmonary hypertension, evaluation of right and left ventricular systolic and/or diastolic function, and screening for pericardial effusions and/or malpositioned central catheters. Neonatal cardiac point-of-care ultrasound (cPOCUS) is a limited cardiovascular evaluation which may include line tip evaluation, identification of pericardial effusion and differentiation of hypovolemia from severe impairment in myocardial contractility in the hemodynamically unstable neonate. This document is the product of an American Society of Echocardiography task force composed of representatives from neonatology-hemodynamics, pediatric cardiology, pediatric cardiac sonography, and neonatology-cPOCUS. This document provides (1) guidance on the purpose and rationale for both TNE and cPOCUS, (2) an overview of the components of a standard TNE and cPOCUS evaluation, (3) disease and/or clinical scenario-based indications for TNE, (4) training and competency-based evaluative requirements for both TNE and cPOCUS, and (5) components of quality assurance. The writing group would like to acknowledge the contributions of Dr. Regan Giesinger who sadly passed during the final revisions phase of these guidelines. Her contributions to the field of neonatal hemodynamics were immense.

Abnormal Shape and Size of the Cardiac Ventricles Are Associated with a Higher Risk of Neonatal Death in Fetuses with Isolated Left Congenital Diaphragmatic Hernia

INTRODUCTION

The objective of this study was to evaluate the association between fetal cardiac deformation analysis (CDA) and cardiac function with severe adverse perinatal outcomes in fetuses with isolated left congenital diaphragmatic hernia (CDH).

METHODS

CDA in each ventricle (contractility, size, and shape), evaluated by speckle tracking and novel FetalHQ software, and markers of cardiac function (E/A ratios, pulmonary and aortic peak systolic velocities, and sigmoid annular valve diameters), were evaluated in fetuses with isolated left CDH. Two evaluations were performed: at referral (CDA and function) and within 3 weeks of delivery (CDA). Severe adverse neonatal outcomes were considered neonatal death (ND) or survival with CDH-associated pulmonary hypertension (CDH-PH). Differences and associations between CDA, cardiac function, and severe adverse outcomes were estimated.

RESULTS

Fifty fetuses were included, and seventeen (34%) had severe adverse neonatal outcomes (11 ND and 6 survivors with CDH-PH). At first evaluation, the prevalence of a small left ventricle was 34% (17/50) with a higher prevalence among neonates presenting severe adverse outcomes (58.8 [10/17] vs. 21.2% [7/33]; p = 0.01; OR, 5.03 [1.4-19.1; p = 0.01]) and among those presenting with neonatal mortality (8/11 [72.7] vs. 9/39 [23.0%]; p = 0.03; OR, 8.9 [1.9-40.7; p = 0.005]). No differences in cardiac function or strain were noted between fetuses with or without severe adverse outcomes. Within 3 weeks of delivery, the prevalence of small left ventricle was higher (19/34; 55.8%) with a more globular shape (reduced transverse/longitudinal ratio). A globular right ventricle was significantly associated with ND or survival with CDH-PH (OR, 14.2 [1.5-138.3]; p = 0.02).

CONCLUSION

Fetuses with isolated CDH at risk of perinatal death or survival with CDH-PH had a higher prevalence of a small left ventricle and abnormal shape of the right ventricle.

Fetal MRI-Based Mediastinal Shift Angle (MSA) and Percentage Area of Left Ventricle (pALV) as Prognostic Parameters for Congenital Diaphragmatic Hernia

OBJECTIVE

Fetal magnetic resonance imaging (MRI) is broadly used as a method for assessing prognosis in congenital diaphragmatic hernia (CDH). In addition to the extent of lung hypoplasia, determined by measuring the lung volume, cardiac impairment due to pulmonary hypertension and left cardiac hypoplasia is decisive for the prognosis. The percentage area of left ventricle (pALV) describes the percentage of the inner area of the left ventricle in relation to the total area, whereas the mediastinal shift angle (MSA) quantifies the extent of cardiac displacement. The prognostic value of pALV and MSA should be evaluated in terms of survival, the need for extracorporeal membrane oxygenation (ECMO) therapy, and the development of chronic lung disease (CLD).

METHODS

In a total of 122 fetal MRIs, the MSA and pALV were measured retrospectively and complete outcome parameters were determined regarding survival for all 122 subjects, regarding ECMO therapy in 109 cases and about the development of CLD in 78 cases. The prognostic value regarding the endpoints was evaluated using logistic regression and ROC analysis.

RESULTS

The MSA was significantly higher in children who received ECMO therapy (p = 0.0054), as well as in children who developed CLD (p = 0.0018). ROC analysis showed an AUC of 0.68 for ECMO requirement and 0.77 with respect to CLD development. The pALV showed a tendency towards higher levels in children who received ECMO therapy (p = 0.0824). The MSA and the pALV had no significant effect on survival (MSA: p = 0.4293, AUC = 0.56; pALV: p = 0.1134, AUC = 0.57).

CONCLUSIONS

The MSA determined in fetal MRI is a suitable prognostic parameter for ECMO requirement and CLD development in CDH patients and can possibly be used as a supplement to the established parameters.

Comparison of the Surgical Outcomes in Neonates with Left-sided Congenital Diaphragmatic Hernia with Only Skin Closure versus Abdominal Muscle Closure

Aim

This study aims to compare the outcome of neonatal left congenital diaphragmatic hernia (CDH, Bochdalek type) repair through laparotomy with and without abdominal muscle closure.

Materials and Methods

This retrospective study was conducted between January 2012 and May 2021 at a neonatal surgical unit of a Tertiary Care Center. Demographic details, preoperative management, Two-dimensional-echo, intra-operative findings, postoperative course, and follow-up data were collected and analyzed.

Results

The study group comprised 50 neonates with a mean standard deviation (SD) age at admission: 4.44 (5.12) days, male: female ratio of 3:2, and mean (SD) weight: 2.73 (0.51) kg. Following repair of the diaphragmatic defect through laparotomy, 26 (52%) underwent skin closure alone, whereas 24 (48%) underwent abdominal muscle closure. Postoperatively, there was a significant fall in the level of platelets (P = 0.021), increase in pressure support by at least 4-5 cm H2O (P = 0.027), and increase in the blood urea (P < 0.001), creatinine (P = 0.005), lactate (P = 0.019), and acidosis (P = 0.048) in the muscle closure group. Although not statistically significant, there was a fall in the urine output and blood pressure in this group. There was no significant difference in the duration of inotropes. Mortality was 8 (32%) in the skin closure group, and 14 (61%) in the muscle closure group (P = 0.05).

Conclusions

Neonates undergoing left CDH repair through the abdominal route with skin closure alone, had better survival, as well as hematological, renal, and ventilatory parameters than those who underwent muscle closure. It is a useful surgical modification to improve outcome in centers with limited facilities.

Hemolysis during Venovenous Extracorporeal Membrane Oxygenation in Neonates with Congenital Diaphragmatic Hernia: A Prospective Observational Study

OBJECTIVE

To investigate the incidence of hemolysis and its association with outcome in neonates with congenital diaphragmatic hernia (CDH) requiring venovenous extracorporeal membrane oxygenation (ECMO) treatment using a Medos Deltastream circuit with a DP3 pump, a hilite 800 LT oxygenator system, and a ¼' tubing.

STUDY DESIGN

Plasma free hemoglobin (PFH) was prospectively measured once daily during ECMO using spectrophotometric testing. Patients (n = 62) were allocated into two groups according to presence or absence of hemolysis. Hemolysis was defined as PFH ≥ 50 mg/dL on at least 2 consecutive days during ECMO treatment. Hemolysis was classified as either moderate with a maximum PFH of 50-100 mg/dL or severe with a maximum PFH >100 mg/dL.

RESULTS

Hemolysis was detected in 14 patients (22.6%). Mortality was 100% in neonates with hemolysis compared with 31.1% in neonates without hemolysis (P < .001). In 21.4% hemolysis was moderate and in 78.6% severe. Using multivariable analysis, hemolysis (hazard ratio: 6.8; 95%CI: 1.86-24.86) and suprasystemic pulmonary hypertension (PH) (hazard ratio: 3.07; 95%CI: 1.01-9.32) were independently associated with mortality. Hemolysis occurred significantly more often using 8 French (Fr) cannulae than 13 Fr cannulae (43% vs 17%; P = .039). Cutoff for relative ECMO flow to predict hemolysis were 115 ml/kg/ minute for patients with 8 Fr cannulae (Area under the curve [AUC] 0.786, P = .042) and 100 ml/kg/ minute for patients with 13 Fr cannulae (AUC 0.840, P < .001).

CONCLUSIONS

Hemolysis in CDH neonates receiving venovenous ECMO is independently associated with mortality.

Unique Cardiopulmonary Interactions in Congenital Diaphragmatic Hernia: Physiology and Therapeutic Implications

Congenital diaphragmatic hernia (CDH) results in abdominal contents entering the thoracic cavity, affecting both cardiac and pulmonary development. Maldevelopment of the pulmonary vasculature occurs within both the ipsilateral lung and the contralateral lung. The resultant bilateral pulmonary hypoplasia and associated pulmonary hypertension are important components of the pathophysiology of this disease that affect outcomes. Despite prenatal referral to specialized high-volume centers, advanced ventilation strategies, pulmonary hypertension management, and the option of extracorporeal membrane oxygenation, overall CDH mortality remains between 25% and 30%. With increasing recognition that cardiac dysfunction plays a large role in morbidity and mortality in patients with CDH, it becomes imperative to understand the different clinical phenotypes, thus allowing for individual patient-directed therapies. Further research into therapeutic interventions that address the cardiopulmonary interactions in patients with CDH may lead to improved morbidity and mortality outcomes.

Prognostic value of echocardiographic parameters in congenital diaphragmatic hernia: a systematic review and meta-analysis

BACKGROUND

Prognostication of mortality and decision to offer extracorporeal membrane oxygenation (ECMO) treatment in infants with congenital diaphragmatic hernia (CDH) can inform clinical management.

OBJECTIVE

To summarise the prognostic value of echocardiography in infants with CDH.

METHODS

Electronic databases Ovid MEDLINE, Embase, Scopus, CINAHL, the Cochrane Library and conference proceedings up to July 2022 were searched. Studies evaluating the prognostic performance of echocardiographic parameters in newborn infants were included. Risk of bias and applicability were assessed using the Quality Assessment of Prognostic Studies tool. We used a random-effect model for meta-analysis to compute mean differences (MDs) for continuous outcomes and relative risk (RR) for binary outcomes with 95% CIs. Our primary outcome was mortality; secondary outcomes were need for ECMO, duration of ventilation, length of stay, and need for oxygen and/or inhaled nitric oxide.

RESULTS

Twenty-six studies were included that were of acceptable methodological quality. Increased diameters of the right and left pulmonary arteries at birth (mm), MD 0.95 (95% CI 0.45 and 1.46) and MD 0.79 (95% CI 0.58 to 0.99), respectively) were associated with survival. Left ventricular (LV) dysfunction, RR 2.40, (95% CI 1.98 to 2.91), right ventricular (RV) dysfunction, RR 1.83 (95% CI 1.29 to 2.60) and severe pulmonary hypertension (PH), RR 1.69, (95% CI 1.53 to 1.86) were associated with mortality. Left and RV dysfunctions, RR 3.30 (95% CI 2.19 to 4.98) and RR 2.16 (95% CI 1.85 to 2.52), respectively, significantly predicted decision to offer ECMO treatment. Limitations are lack of consensus on what parameter is optimal and standardisation of echo assessments.

CONCLUSIONS

LV and RV dysfunctions, PH and pulmonary artery diameter are useful prognostic factors among patients with 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.

Early echocardiographic pulmonary artery measurements as prognostic indicators in left congenital diaphragmatic hernia

BACKGROUND

To predict whether the left pulmonary artery (LPA) to the main pulmonary artery (MPA) ratio measured by echocardiography in left congenital diaphragmatic hernia (CDH) was related to death or need for extracorporeal membrane oxygenation (ECMO).

METHODS

This retrospective study analyzed neonates with left CDH born between 2018 and 2022 in a single tertiary medical institution. Echocardiography was performed immediately after birth. The diameter of the LPA was measured at the bifurcation, and the diameter of the MPA was measured at the maximal dimension during the systolic phase. The Nakata index, McGoon ratio, and ejection fraction (EF) were analyzed and compared with the LPA: MPA ratio as predictive values.

RESULTS

Seventy-two neonates with left CDH were included, 19 (26.4%) died or needed ECMO, and 53 (73.6%) survived without ECMO. The lower observed/expected lung-to-head ratio, lower EF, lower LPA: MPA ratio, lower RPA: MPA ratio, lower Nakata index, and lower McGoon ratio were associated with death or need for ECMO. By multivariate analysis, lower LPA: MPA ratio, RPA: MPA ratio, and Nakata index were independent postnatal risk factors for death or need for ECMO. Among the measurements, the LPA: MPA ratio had the highest area under the curve (0.957) with a sensitivity of 84.2% and specificity of 96.3% at a cut-off value of 31.2%.

CONCLUSION

In patients with left CDH, the LPA: MPA ratio measured by echocardiography could be used as an independent postnatal predictor of death or need for ECMO.

Failure to Normalize Biventricular Function Is Associated with Extracorporeal Membrane Oxygenation Use in Neonates with Congenital Diaphragmatic Hernia

We examined postnatal echocardiograms for 62 infants with congenital diaphragmatic hernia born from 2014 through 2020. Left and right ventricular dysfunction on D0 were sensitive, whereas persistent dysfunction on D2 was specific for extracorporeal membrane oxygenation requirement. Biventricular dysfunction had the strongest association with extracorporeal membrane oxygenation. Serial echocardiography may inform prognosis in congenital diaphragmatic hernia.

Dynamics of pulmonary hypertension severity in the first 48 h in neonates with prenatally diagnosed congenital diaphragmatic hernia

Introduction

Pulmonary hypertension (PH) is one of the major contributing factors to the high morbidity and mortality in neonates with congenital diaphragmatic hernia (CDH). The severity and duration of postnatal PH are an established risk factor for patient outcome; however, the early postnatal dynamics of PH have not been investigated. This study aims to describe the early course of PH in CDH infants, and its relation to established prognostic markers and outcome measures.

Methods

We performed a monocentric retrospective review of neonates with prenatally diagnosed CDH, who received three standardized echocardiographic examinations at 2-6 h, 24, and 48 h of life. The degree of PH was graded as one of three categories: mild/no, moderate, or severe PH. The characteristics of the three groups and their course of PH over 48 h were compared using univariate and correlational analyses.

Results

Of 165 eligible CDH cases, initial PH classification was mild/no in 28%, moderate in 35%, and severe PH in 37%. The course of PH varied markedly based on the initial staging. No patient with initial no/mild PH developed severe PH, required extracorporeal membrane oxygenation (ECMO)-therapy, or died. Of cases with initial severe PH, 63% had persistent PH at 48 h, 69% required ECMO, and 54% died. Risk factors for any PH included younger gestational age, intrathoracic liver herniation, prenatal fetoscopic endoluminal tracheal occlusion (FETO)-intervention, lower lung to head ratio (LHR), and total fetal lung volume (TFLV). Patients with moderate and severe PH showed similar characteristics, except liver position at 24- (p = 0.042) and 48 h (p = 0.001), mortality (p = 0.001), and ECMO-rate (p = 0.035).

Discussion

To our knowledge, this is the first study to systematically assess the dynamics of PH in the first postnatal 48 h at three defined time points. CDH infants with initial moderate and severe PH have a high variation in postnatal PH severity over the first 48 h of life. Patients with mild/no PH have less change in PH severity, and an excellent prognosis. Patients with severe PH at any point have a significantly higher risk for ECMO and mortality. Assessing PH within 2-6 h should be a primary goal in the care for CDH neonates.

Early nitric oxide is not associated with improved outcomes in congenital diaphragmatic hernia

BACKGROUND

Inhaled nitric oxide (iNO) is widely used for the management of infants with congenital diaphragmatic hernia (CDH); however, evidence of benefit is limited.

METHODS

This is a multicenter cohort study using data from the Congenital Diaphragmatic Hernia Study Group between 2015 and 2020. The impact of early iNO use in the first 3 days of life prior to ECLS use on mortality or ECLS use was explored using multivariate logistic regression models and subgroup analyses.

RESULTS

Of the 1777 infants, 863 (48.6%) infants received early iNO treatment. Infants receiving iNO had lower birth weight, larger defect size, more severe pulmonary hypertension, and abnormal ventricular size and function. After controlling for these factors, early iNO use was associated with increased mortality (aOR 2.06, 95% CI 1.05-4.03, P = 0.03) and increased ECLS use (aOR 3.44, 95% CI 2.11-5.60, P < 0.001). Subgroup analyses after stratification by echocardiographic characteristics and defect size revealed no subgroup with a reduction in mortality or ECLS use.

CONCLUSIONS

Use of iNO in the first 3 days of life prior to ECLS was not associated with a reduction in mortality or ECLS use in either the regression models or the subgroup analyses. The widespread use of iNO in this vulnerable population requires reconsideration.

IMPACT

Evidence to support widespread use of iNO for infants with congenital diaphragmatic hernia is limited. The use of iNO in the first 3 days of life was associated with significantly increased mortality and ECLS use. Stratification by echocardiographic characteristics and defect size did not reveal a subgroup that benefited from iNO. Even the subset of patients with R-to-L shunts at both ductal and atrial levels, a surrogate for elevated pulmonary arterial pressures in the absence of significantly decreased LV compliance, did not benefit from early iNO use. Early iNO therapy was of no benefit in the management of acute pulmonary hypertension in infants with congenital diaphragmatic hernia, supporting reconsideration of its use in this population.

Beyond the diaphragm and the lung: a multisystem approach to understanding congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a birth defect characterized by the incomplete closure of the diaphragm and herniation of abdominal organs into the chest during gestation. This invariably leads to an impairment in fetal lung development (pulmonary hypoplasia) that involves the pulmonary vessels (vascular remodeling) leading to postnatal pulmonary hypertension. Moreover, approximately 60% of CDH survivors have long-term comorbidities, including critical cardiac anomalies, neurodevelopmental impairment, gastroesophageal reflux, and musculoskeletal malformations. While the pathophysiology of the diaphragmatic defect and pulmonary hypoplasia have been studied in detail over the decades, less is known about the other organs affected in CDH. In this review, we searched the literature for reports on other organs beyond the lung and diaphragm in human and experimental models of CDH. We found studies reporting gross morphometric changes and alterations to biological pathways in the heart, brain, liver, kidney, gastrointestinal tract, and musculoskeletal system. Given the paucity of literature and the importance that these comorbidities play in the life of patients with CDH, further studies are needed to comprehensively uncover the pathophysiology of the changes observed in these other organs.

Role of microRNAs in Congenital Diaphragmatic Hernia-Associated Pulmonary Hypertension

Epigenetic regulators such as microRNAs (miRNAs) have a key role in modulating several gene expression pathways and have a role both in lung development and function. One of the main pathogenetic determinants in patients with congenital diaphragmatic hernia (CDH) is pulmonary hypertension (PH), which is directly related to smaller lung size and pulmonary microarchitecture alterations. The aim of this review is to highlight the importance of miRNAs in CDH-related PH and to summarize the results covering this topic in animal and human CDH studies. The focus on epigenetic modulators of CDH-PH offers the opportunity to develop innovative diagnostic tools and novel treatment modalities, and provides a great potential to increase researchers’ understanding of the pathophysiology of CDH.

Preliminary study on the predictive value of the vasoactive-inotropic score for the prognosis of neonatal congenital diaphragmatic hernia

BACKGROUND

No study has reported on the relationship between the vasoactive-inotropic score (VIS) and the prognosis of neonates with a severe congenital diaphragmatic hernia (CDH). This study aimed to identify potential risk factors for mortality in patients with CDH. We calculated the VIS based on the vasoactive drugs used during the perioperative period to investigate the relationship between VIS and infant prognosis.

METHODS

We retrospectively analyzed the clinical data of 75 neonates with CDH who were treated at our center between January 2016 and October 2021. We calculated the maximum and mean VIS during the first 24 h of hospitalization (hosVIS [24max] and hosVIS [24mean], respectively) and after surgery (postVIS [24max] and postVIS [24mean], respectively). The relationship between the VIS and the prognosis of neonates with CDH was analyzed using a receiver operating characteristic (ROC) curve, t-test, chi-square test, rank-sum test, and logistic regression analysis.

RESULTS

In total, 75 participants with CDH were included in the study. The chance of survival was 80%. Our results showed that hosVIS (24max) was an accurate predictor of prognosis (area under the ROC curve = 0.925, p = 0.007). The calculated optimal critical value of hosVIS (24max) for predicting a poor prognosis was 17 (J = 0.75). Multivariate analysis revealed that hosVIS (24max) was an independent risk factor for death in neonates with CDH.

CONCLUSION

In neonates with CDH, a higher VIS, especially hosVIS (24max), suggests worsened cardiac function, a more severe condition, and a higher risk of death. The rising VIS score in infants prompts physicians to implement more aggressive treatment to improve cardiovascular function.

Ductus arteriosus flow predicts outcome in neonates with congenital diaphragmatic hernia

OBJECTIVE

To investigate whether the pattern of flow through the ductus arteriosus (DA) is associated with the need for extracorporeal membrane oxygenation support (ECMO) or death in neonates with congenital diaphragmatic hernia (CDH).

DESIGN

Retrospective observational study.

SETTING

German level III Neonatal Intensive Care Unit.

PARTICIPANTS

One hundred and nine CDH neonates were born between March 2009 and May 2021.

METHODS

DA flow pattern was assessed in echocardiograms obtained within 24 h of life by measuring flow time and velocity time integral (VTI) for both left-to-right (LR) and right-to-left (RL) components of the ductal shunt. A VTI ratio (VTILR/VTIRL) < 1.0 and an RL relative flow time (flow timeRL/(Flow timeLR+Flow timeRL)) >33% were defined as markers of abnormal flow patterns. The primary outcome was the need for ECMO. The secondary outcome was death.

RESULTS

Seventy-two patients (51.8%) had a VTI ratio <1.0, 73 (52.5%) an RL relative flow time >33%. Fifty-nine patients (42.4%) had an alteration of both values. Need for ECMO was present in 37.4% (n = 52), while 19.4% (n = 27) died. A VTI ratio <1.0 had the highest diagnostic accuracy for the need for ECMO, (sensitivity 82.7%, specificity 66.7%, negative predictive value [NPV] 86.6%, and positive predictive value [PPV] 59.7%) as well as for death (sensitivity 77.8%, specificity 54.5%, NPV 91.0%, and PPV 29.2%). Patients with VTI ratio <1.0 were 4.7 times more likely to need ECMO and 3.3 times more likely to die. VTI ratio values correlated significantly with pulmonary hypertension (PH) severity (r = -0.516, p < 0.001).

CONCLUSIONS

A VTI ratio <1.0 is a valuable threshold to identify high-risk CDH neonates. For improved risk stratification, other parameters-for example, left ventricular cardiac dysfunction-should be combined with DA flow assessment.