Management of congenital diaphragmatic hernia: A systematic review from the APSA outcomes and evidence based practice committee

Mortality trends in neonatal ECMO for pulmonary hypoplasia: A review of the Extracorporeal Life Support Organization database from 1981 to 2016

BACKGROUND

The purpose of this review is to provide ECMO outcome data for medical personnel who counsel families of patients with pulmonary hypoplasia (PH), often secondary to renal abnormalities. We report diagnoses and outcomes associated with PH in neonates that were treated with ECMO over the past 35 years.

METHODS

Retrospective cohort study using the ELSO database for neonates born between 1981 and 2016 with a primary or secondary diagnosis of PH. Five patient groups were created based on ICD-9 codes. Mortality rates were compared and trends over time were investigated.

RESULTS

Thirty-three percent of the 1385 patients survived to discharge. Congenital diaphragmatic hernia (CDH) patients had significantly higher mortality than PH patients secondary to renal dysplasia (p < 0.001). Mortality decreased significantly over time for all groups (p < 0.001). The proportion of patients alive at discharge increased over time for CDH patients (p < 0.001), whereas survival decreased for patients with PH secondary to renal dysplasia (p = 0.012).

CONCLUSIONS

Neonates with PH that require ECMO have high mortality rates, which have generally decreased over the past 35 years; however, mortality for neonates with PH secondary to renal dysplasia continues to increase. We speculate that the apparent rise in mortality for these patients is because of changes in patient selection subsequent to improvements in non-ECMO ventilatory support.

LEVEL OF EVIDENCE

II.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

DISCUSSION/CONCLUSION

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

Porcine dermal patches as a risk factor for recurrence after congenital diaphragmatic hernia repair

PURPOSE

Recurrence of congenital diaphragmatic hernia (CDH) is a treatment-related morbidity which can be preventable. There is no consensus about the ideal material for diaphragmatic substitution. The aim of our study is to identify if the use of porcine dermis patches increases the risk of CDH recurrence.

METHODS

Retrospective review of medical records of CDH patients treated between 2013 and 2017 in our center was carried out. Demographic, clinical and surgical variables were collected. Regression analysis was performed to identify which factors increase the risk of recurrence.

RESULTS

50 patients entered the study. 94% of the patients had a left CDH, mean observed/expected lung-to-head ratio was 46%. 17 patients underwent a primary closure, the rest a patch closure: 25 Gore-Tex^® and 8 porcine dermis patches were used. Seven patients presented recurrence (14%). Median follow-up time was 3.5 years (1.2-6.2). Univariate analysis revealed that the use of a porcine dermis patch (75%) increased the risk of recurrence compared with Gore-Tex^® patch (4%) and primary closure (0%) p < 0.001 (HR 58.7; IC 95%: 6.9-501.2; p < 0.001).

CONCLUSION

The main risk factor for CDH recurrence is the use of a porcine dermis patch. We do not recommend the use of these patches for CDH repair.

Respiratory Support of Infants With Congenital Diaphragmatic Hernia

Optimisation of respiratory support of infants with congenital diaphragmatic hernia (CDH) is critical. Infants with CDH often have severe lung hypoplasia and abnormal development of their pulmonary vasculature, leading to ventilation perfusion mismatch. It is vital that lung protective ventilation strategies are employed during both initial stabilisation and post-surgical repair to avoid ventilator induced lung damage and oxygen toxicity to prevent further impairment to an already diminished gas-exchanging environment. There is a lack of robust evidence for the routine use of surfactant therapy during initial resuscitation of infants with CDH and thus administration cannot be recommended outside clinical trials. Additionally, inhaled nitric oxide has been shown to have no benefit in reducing the mortality rates of infants with CDH. Other therapeutic agents which beneficially act on pulmonary hypertension are currently being assessed in infants with CDH in randomised multicentre trials. The role of novel ventilatory modalities such as closed loop automated oxygen control, liquid ventilation and heliox therapy may offer promise for infants with CDH, but the benefits need to be determined in appropriately designed clinical trials.

ATS Core Curriculum 2020. Pediatric Pulmonary Medicine

The American Thoracic Society Core Curriculum updates clinicians annually in adult and pediatric pulmonary disease, medical critical care, and sleep medicine, in a 3- to 4-year recurring cycle of topics. These topics will be presented at the 2020 International Conference. Below is the pediatric pulmonary medicine core, including pediatric hypoxemic respiratory failure; modalities in noninvasive management of chronic respiratory failure in childhood; surgical and nonsurgical management of congenital lung malformations; an update on smoke inhalation lung injury; an update on vaporizers, e-cigarettes, and other electronic delivery systems; pulmonary complications of sarcoidosis; pulmonary complications of congenital heart disease; and updates on the management of congenital diaphragmatic hernia.

Predicting lethal pulmonary hypoplasia in congenital diaphragmatic hernia (CDH): Institutional experience combined with CDH registry outcomes

BACKGROUND

The Severe Pulmonary Hypoplasia and Evaluation for Resuscitative Efforts (SPHERE) protocol was developed to attempt to identify CDH patients with likely lethal pulmonary hypoplasia. We present our experience with this protocol and utilize the CDH Registry to critically assess the protocol.

METHODS

SPHERE patients identified based on prenatal imaging (10/2009-1/2018) were offered ECMO if meeting postnatal physiologic criteria, while others received comfort measures. Within the CDH Registry, patients with suspected severe CDH were identified and separated into "passed" (lowest pCO2 ≤100) versus "failed" (lowest pCO2 >100) groups.

RESULTS

Of 23 SPHERE patients, 57% (13/23) passed criteria for ECMO and survival was 46% (6/13) in that cohort. Of 4912 patients in the CDH Registry, 265 met criteria. There was no difference in survival rates between those that "passed" (122/227; 54%) versus "failed" (18/38; 47%). However, the latter had longer ECMO runs and more required ventilator/ECMO support at 30 days. Amongst survivors, the "failed" group had longer hospital stays and more frequently required tube feeds at discharge.

CONCLUSIONS

The SPHERE protocol did not predict mortality in the CDH Registry. However, our data suggest resource utilization is significant when unable to reach pCO2 ≤100 despite resuscitation. Morbidity remains high in this group.

LEVEL OF EVIDENCE

Level III ANNOTATION OF CHANGES: Institutional Review Board Approval at University of Michigan (HUM00031524 and HUM00044010) TYPE OF STUDY: Retrospective Review.

Update on Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) is a rare developmental defect of the diaphragm, characterized by herniation of abdominal contents into the chest that results in varying degrees of pulmonary hypoplasia and pulmonary hypertension (PH). Significant advances in the prenatal diagnosis and identification of prognostic factors have resulted in the continued refinement of the approach to fetal therapies for CDH. Postnatally, protocolized approaches to lung-protective ventilation, nutrition, prevention of infection, and early aggressive management of PH have led to improved outcomes in infants with CDH. Advances in our understanding of the associated left ventricular (LV) hypoplasia and myocardial dysfunction in infants with severe CDH have allowed for the optimization of hemodynamics and management of PH. This article provides a comprehensive review of CDH for the anesthesiologist, focusing on the complex pathophysiology, advances in prenatal diagnosis, fetal interventions, and optimal postnatal management of CDH.

Extracellular vesicles influence the pulmonary arterial extracellular matrix in congenital diaphragmatic hernia

OBJECTIVE

Abnormal pulmonary vasculature directly affects the development and progression of congenital diaphragmatic hernia (CDH)-associated pulmonary hypertension (PH). Though overarching structural and cellular changes in CDH-affected pulmonary arteries have been documented, the precise role of the extracellular matrix (ECM) in the pulmonary artery (PA) pathophysiology remains undefined. Here, we quantify the structural, compositional, and mechanical CDH-induced changes in the main and distal PA ECM and investigate the efficacy of mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) as a therapy to ameliorate pathological vascular ECM changes.

METHODS

Pregnant Sprague-Dawley rodents were administered nitrofen to induce CDH-affected pulmonary vasculature in the offspring. A portion of CDH-affected pups was treated with intravenous infusion of MSC-EVs (1 × 10¹⁰ /mL) upon birth. A suite of histological, mechanical, and transmission electron microscopic analyses were utilized to characterize the PA ECM.

RESULTS

The CDH model main PA presented significantly altered characteristics-including greater vessel thickness, greater lysyl oxidase (LOX) expression, and a relatively lower ultimate tensile strength of 13.6 MPa compared to control tissue (25.1 MPa), suggesting that CDH incurs ECM structural disorganization. MSC-EV treatment demonstrated the potential to reverse CDH-related changes, particularly through rapid inhibition of ECM remodeling enzymes (LOX and MMP-9). Additionally, MSC-EV treatment bolstered structural aspects of the PA ECM and mitigated pathological disorganization as exhibited by increased medial wall thickness and stiffness that, while not significantly altered, trends away from CDH-affected tissue.

CONCLUSIONS

These data demonstrate notable ECM remodeling in the CDH pulmonary vasculature, along with the capacity of MSC-EVs to attenuate pathological ECM remodeling, identifying MSC-EVs as a potentially efficacious therapeutic for CDH-associated pulmonary hypertension.

Using airway resistance measurement to determine when to switch ventilator modes in congenital diaphragmatic hernia: a case report

Background

Congenital diaphragmatic hernia is a deficiency of the fetal diaphragm resulting in herniation of the abdominal viscera into the thoracic cavity. The best method of respiratory management of congenital diaphragmatic hernia is unclear, but high frequency oscillatory ventilation is often used as the initial ventilator mode for severe congenital diaphragmatic hernia. When it becomes impossible to maintain the pre-ductal saturations, the timing of successful switching of the ventilation mode from high frequency oscillatory ventilation to conventional mechanical ventilation remains unclear. Herein, we reported two cases in which airway resistance measurements based on pulmonary function tests were used for making the decision to switch the ventilator mode from high frequency oscillatory ventilation to conventional mechanical ventilation in patients with left isolated congenital diaphragmatic hernia.

Case presentation

Two 0-day-old infants with congenital diaphragmatic hernia were admitted to our hospital. In both patients, high frequency oscillatory ventilation was started initially, and the levels of saturation gradually rose within a few hours after birth. After 24 h of high frequency oscillatory ventilation, the level of saturation decreased, and the dissociation of pre-ductal and post-ductal saturation re-occurred. The respiratory-system resistance was 515 and 403 cmH₂O·kg/L/s, respectively. Because the respiratory-system resistance was elevated, we decided to change the ventilator mode from high frequency oscillatory ventilation to conventional mechanical ventilation. After switching to conventional mechanical ventilation, the patients’ heart rate and saturation increased immediately.

Conclusions

In patients with congenital diaphragmatic hernia, resistance levels of > 400 cmH₂O·kg/L/s may indicate high airway resistance and suggest greater alveolar vibration attenuation. When respiratory-system resistance reaches over 400 cmH₂O·kg/L/s, it may be an optimal time for switching from high frequency oscillatory ventilation to conventional mechanical ventilation.

Left-sided congenital diaphragmatic hernia: can we improve survival while decreasing ECMO?

BACKGROUND

Mortality and ECMO rates for congenital diaphragmatic hernia (CDH) remain ~30%. In 2016, we changed our CDH guidelines to minimize stimulation while relying on preductal oxygen saturation, lower mean airway pressures, stricter criteria for nitric oxide (iNO), and inotrope use. We compared rates of ECMO, survival, and survival without ECMO between the two epochs.

DESIGN/METHODS

Retrospective review of left-sided CDH neonates at the University of Utah/Primary Children's Hospital NICUs during pre (2003-2015, n = 163) and post (2016-2019, n = 53) epochs was conducted. Regression analysis controlled for defect size and intra-thoracic liver.

RESULTS

Following guideline changes, we identified a decrease in ECMO (37 to 13%; p = 0.001) and an increase in survival without ECMO (53 to 79%, p = 0.0001). Overall survival increased from 74 to 89% (p = 0.035).

CONCLUSION(S)

CDH management guideline changes focusing on minimizing stimulation, using preductal saturation and less aggressive ventilator/inotrope support were associated with decreased ECMO use and improved survival.

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

Rationale: Congenital diaphragmatic hernia (CDH) is an anomaly with a high morbidity and mortality. Cardiac dysfunction may be an important and underrecognized contributor to CDH pathophysiology and determinant of disease severity.Objectives: Our aim was to investigate the association between early, postnatal ventricular dysfunction and outcome among infants with CDH.Methods: Multicenter, prospectively collected data in the CDH Study Group (CDHSG) registry, abstracted between 2015 and 2018, were evaluated. Ventricular function on early echocardiograms, defined as obtained within the first 48 hours of life, was categorized into four hierarchical groups: normal function, right ventricular dysfunction only (RV_dys), left ventricular dysfunction only (LV_dys), and combined RV and LV dysfunction (RV&LV_dys). Univariate, multivariate, and Cox proportional hazards regression analyses were performed.Measurements and Main Results: Cardiac function data from early echocardiograms were available for 1,173 (71%) cases and categorized as normal in 711 (61%), RV_dys in 182 (15%), LV_dys in 61 (5%), and combined RV&LV_dys in 219 (19%) cases. Ventricular dysfunction was significantly associated with prenatal diagnosis, CDHSG stage, intrathoracic liver, and patch repair (all P < 0.001). Survival varied by category: normal function, 80%; RV_dys, 74%; LV_dys, 57%; and RV&LV_dys, 51% (P < 0.001). The adjusted risk of death (hazard ratio) for cases with LV_dys was 1.96 (95% confidence interval [CI], 1.29-2.98; P = 0.020) and for cases with RV&LV_dys was 2.27 (95% CI, 1.77-2.92; P = 0.011). All cardiac dysfunction categories were associated with use of extracorporeal membrane oxygenation (P < 0.005).Conclusions: Early ventricular dysfunction occurs frequently in CDH and is an independent determinant of severity and clinical outcome.

Inhaled Nitric Oxide Is Associated with Improved Oxygenation in a Subpopulation of Infants with Congenital Diaphragmatic Hernia and Pulmonary Hypertension

OBJECTIVES

To determine which patients with congenital diaphragmatic hernia (CDH) and pulmonary hypertension (PH) benefit from inhaled nitric oxide (iNO) treatment by comparing characteristics and outcomes of iNO responders to nonresponders.

STUDY DESIGN

We performed a retrospective chart review of infants with CDH treated at our center between 2011 and 2016. In a subset of patients, iNO was initiated for hypoxemia or echocardiographic evidence of extrapulmonary right to left shunting. Initial post-treatment blood gases were reviewed, and patients were classified as responders (increased PaO₂ >20 mm Hg) or nonresponders. Baseline characteristics, echocardiograms and outcomes were compared between groups with Fisher exact tests and Mann-Whitney t tests, as appropriate.

RESULTS

During the study period, 95 of 131 patients with CDH (73%) were treated with iNO. All patients with pretreatment echocardiograms (n = 90) had echocardiographic evidence of PH. Thirty-eight (40%) patients met treatment response criteria. Responders had significant improvements in PaO₂ (51 ± 3 vs 123 ± 7 mm Hg, P < .01), alveolar-arterial gradient (422 ± 30 vs 327 ± 27 mm Hg, P < .01), and PaO₂ to FiO₂ ratio (82 ± 10 vs 199 ± 15 mm Hg, P < .01). Nonresponders were more likely to have left ventricular systolic dysfunction (27% vs 8%, P = .03) on echocardiogram. Responders were less likely to require extracorporeal membrane support (50 vs 24%, P = .02).

CONCLUSIONS

iNO treatment is associated with improved oxygenation and reduced need for ECMO in a subpopulation of patients with CDH with PH and normal left ventricular systolic function.

Surgical Complications in Children with CDH: A Multivariate Analysis

Introduction

Several medical and surgical improvements in the treatment of congenital diaphragmatic hernia (CDH) patients have led to a higher survival rate. However, some of these improvements also lead to an increased morbidity rate. This study aims to determine the contribution different medical and surgical treatments have had on the development of surgical complications.

Method

All CDH patients treated in a single centre between 2000 and 2015 were retrospectively evaluated. Multivariate logistic regression was used to estimate the independent effects of several treatment options that could influence the surgical outcome by adjustment for multiple risk factors.

Results

Sixty of the 197 surgically repaired CDH patients had surgical complications. There were more haemorrhagic complications in the ECMO compared to non-ECMO group (27% vs. 2%, p < 0.001). The use of inhaled nitric oxide was also significantly related to haemorrhage (OR = 13.0 (95% CI 1.1–159)). After adjustment for other risk factors, chylothorax was neither significantly associated with ECMO treatment (OR = 1.6 (95% CI 0.5–5.2) nor with patch repair (OR = 2.1: 95% CI 0.7–6.1). A recurrence occurred more often in patients with pulmonary hypertension (OR = 10.0 (95% CI 1.5–65.8) and after treatment with an abdominal patch (OR = 11.3: 95% CI 1.5–84.4).

Conclusion

ECMO treatment and the inhalation of nitric oxide are used in the most severe CDH patients but are associated with a higher risk on surgical haemorrhage. The recurrence rate is associated with both the use of an abdominal patch and the presence of pulmonary hypertension, regardless of medical treatment.

Comparative outcomes of right versus left congenital diaphragmatic hernia: A multicenter analysis

BACKGROUND

Congenital diaphragmatic hernia (CDH) occurs in 1 out of 2500-3000 live births. Right-sided CDHs (R-CDHs) comprise 25% of all CDH cases, and data are conflicting on outcomes of these patients. The aim of our study was to compare outcomes in patients with right versus left CDH (L-CDH).

METHODS

We analyzed a multicenter prospectively enrolled database to compare baseline characteristics and outcomes of neonates enrolled from January 2005 to January 2019 with R-CDH vs. L-CDH.

RESULTS

A total of 588, 495 L-CDH, and 93 R-CDH patients with CDH were analyzed. L-CDHs were more frequently diagnosed prenatally (p=0.011). Lung-to-head ratio was similar in both cohorts. R-CDHs had a lower frequency of primary repair (p=0.022) and a higher frequency of need for oxygen at discharge (p=0.013). However, in a multivariate analysis, need for oxygen at discharge was no longer significantly different. There were no differences in long-term neurodevelopmental outcomes assessed at two year follow up. There was no difference in mortality, need for ECMO, pulmonary hypertension, or hernia recurrence.

CONCLUSION

In this large series comparing R to L-CDH patients, we found no significant difference in mortality, use of ECMO, or pulmonary complications. Our study supports prior studies that R-CDHs are relatively larger and more often require a patch or muscle flap for repair.

TYPE OF STUDY

Prognosis study LEVEL OF EVIDENCE: Level II.

Congenital diaphragmatic eventration and hernia sac compared to CDH with true defects: a retrospective cohort study

Congenital diaphragmatic eventration (CDE) and congenital diaphragmatic hernia (CDH) with or without hernia sac are three different types of congenital diaphragmatic malformations, which this study evaluates. All surgically treated patients with CDE or Bochdalek type CDH between 2000 and 2016 were included in this retrospective analysis. Demographics, CDH-characteristics, treatment, and clinical outcome were evaluated. In total, 200 patients were included. Patients with an eventration or hernia sac had no significant differences and were compared as patients without a true defect to patients with a true defect. The 1-year survival of patients with a true defect was significantly lower than patients with no true defect (76% versus 97%, p = 0.001). CDH with no true defect had significantly better short-term outcomes than CDH with true defect requiring patch repair. However, at 30 days, they more often required oxygen supplementation (46% versus 26%, p = 0.03) and had a higher recurrence rate (8% versus 0%, p = 0.006) (three eventration and two hernia sac patients). Conclusion: Patients without a true defect seem to have a more similar clinical outcome than CDH patients with a true defect, with a better survival. However, the recurrence rate and duration of oxygen supplementation at 30 days are higher than CDH patients with a true defect.What is Known:• Congenital diaphragmatic hernia with or without hernia sac and congenital diaphragmatic eventration (incomplete muscularization) are often treated similarly.• Patients with hernia sac and eventration are thought to have a relatively good outcome, but exact numbers are not described.What is New:• Congenital diaphragmatic eventration and patients with hernia sac seem to have a more similar clinical outcome than Bochdalek type CDH with a true defect.• Patients without a true defect (eventration or hernia sac) have a high recurrence rate.

Longitudinal Analysis of Pulmonary Function in Survivors of Congenital Diaphragmatic Hernia

OBJECTIVE

To analyze longitudinal trends of pulmonary function testing in patients with congenital diaphragmatic hernia (CDH) followed in our multidisciplinary clinic.

STUDY DESIGN

This was a retrospective cohort study of CDH patients born between 1991 and 2013. A linear mixed effects model was fitted to estimate the trends of percent predicted forced expiratory volume in 1 second (FEV₁pp), percent predicted forced vital capacity (FVCpp), and FEV₁/FVC over time.

RESULTS

Of 268 patients with CDH who survived to discharge, 119 had at least 1 pulmonary function test study. The FEV₁pp (P < .001), FVCpp (P = .017), and FEV₁/FVC (P = .001) decreased with age. Compared with defect size A/B, those with defect size C/D had lower FEV₁pp by an average of 11.5% (95% CI, 2.9%-20.1%; P = .010). A history of oxygen use at initial hospital discharge also correlated with decreased FEV₁pp by an average of 8.0% (95% CI, 1.2%-15.0%; P = .023).

CONCLUSIONS

In a select cohort of CDH survivors, average pulmonary function declines with age relative to expected population normative values. Those with severe CDH represent a population at risk for worsening pulmonary function test measurements who may benefit from recognition and monitoring for complications.

A multifactorial severity score for left congenital diaphragmatic hernia in a high-risk population using fetal magnetic resonance imaging

BACKGROUND

Adverse outcomes for infants born with left congenital diaphragmatic hernia (CDH) have been correlated with fetal imaging findings.

OBJECTIVE

We sought to corroborate these correlations in a high-risk cohort and describe a predictive mortality algorithm combining multiple imaging biomarkers for use in prenatal counseling.

MATERIALS AND METHODS

We reviewed fetal MRI examinations at our institution from 2004 to 2016 demonstrating left-side CDH. MRI findings, hospital course and outcomes were recorded and analyzed using bivariate and multivariable analysis. We generated a receiver operating curve (ROC) to determine a cut-off relation for mortality. Finally, we created a predictive mortality calculator.

RESULTS

Of 41 fetuses included in this high-risk cohort, 41% survived. Per bivariate analysis, observed-to-expected total fetal lung volume (P=0.007), intrathoracic position of the stomach (P=0.049), and extracorporeal membrane oxygenation (ECMO) requirement (P<0.001) were significantly associated with infant mortality. Youden J statistic optimized the ROC for mortality at 24% observed-to-expected total fetal lung volume (sensitivity 64%, specificity 82%, area under the curve 0.72). On multivariable analysis, observed-to-expected total fetal lung volume ± 24% was predictive of mortality (adjusted odds ratio, 95% confidence interval: 0.09 [0.02, 0.55]; P=0.008). We derived a novel mortality prediction calculator from this analysis.

CONCLUSION

In this high-risk cohort, decreased observed-to-expected total fetal lung volume and stomach herniation were significantly associated with mortality. The novel predictive mortality calculator utilizes information from fetal MR imaging and provides prognostic information for health care providers. Creation of similar predictive tools by other institutions, using their distinct populations, might prove useful in family counseling, especially where there are discordant imaging findings.

Surgical management of critical congenital malformations in the delivery room

Newborn emergencies that occur in the delivery room are frequently the result of life-threatening congenital anomalies that can result in death or severe disability if not treated in the immediate postnatal period. Prompt recognition and treatment of such disorders are paramount to ensuring the wellbeing of the infant. As congenital anomalies are frequently being diagnosed earlier due to improved prenatal detection, the coordination of planned interventions for life-threatening malformations is also becoming more common. This article serves as a guide for the presentation and initial management of the most common non-cardiac, newborn surgical emergencies.

Effect of lung hypoplasia on the cardiorespiratory transition in newborn lambs

Newborns with lung hypoplasia (LH) commonly have limited respiratory function and often require ventilatory assistance after birth. We aimed to characterize the cardiorespiratory transition and respiratory function in newborn lambs with LH. LH was induced by draining fetal lung liquid in utero [110-133 days (d), term = 147d, n = 6]. At ~133d gestation, LH and Control lambs (n = 6) were instrumented and ventilated for 3 h to monitor blood-gas status, oxygenation, ventilator requirements, and hemodynamics during the transition from fetal to newborn life. Lambs with LH had significantly reduced relative wet and dry lung weights indicating hypoplastic lungs compared with Control lambs. LH lambs experienced persistent hypercapnia and acidosis during the ventilation period, had lower lung compliance, and had higher alveolar-arterial differences in oxygen and oxygenation index compared with Control lambs. As a result, LH lambs required greater respiratory support and more supplemental oxygen. Following delivery, LH lambs experienced periods of significantly lower pulmonary artery blood flow and higher carotid artery blood flow in association with the lower oxygenation levels. The detrimental effects of LH can be attributed to a reduction in lung size and poorer gas exchange capabilities. This study has provided greater understanding of the effect of LH itself on the physiology underpinning the transition from fetal to newborn life. Advances in this area is the key to identifying improved or novel management strategies for babies with LH starting in the delivery room, to favorably alter the fetal-to-newborn transition toward improved outcomes and reduced lifelong morbidity.NEW & NOTEWORTHY Current clinical management of newborns with lung hypoplasia (LH) is largely based on expert opinion rather than scientific evidence. We have generated physiological evidence for detrimental effects of LH on hemodynamics and respiratory function in newborn lambs, which mimics the morbidity observed in LH newborns clinically. The unfavorable consequences of LH can be attributed to a reduction in lung size and poorer gas exchange capabilities.

Potential survival benefit with repair of congenital diaphragmatic hernia (CDH) after extracorporeal membrane oxygenation (ECMO) in select patients: Study by ELSO CDH Interest Group

PURPOSE

Studying the timing of repair in CDH is prone to confounding factors, including variability in disease severity and management. We hypothesized that delaying repair until post-ECMO would confer a survival benefit.

METHODS

Neonates who underwent CDH repair were identified within the ELSO Registry. Patients were then divided into on-ECMO versus post-ECMO repair. Patients were 1:1 matched for severity based on pre-ECMO covariates using the propensity score (PS) for the timing of repair. Outcomes examined included mortality and severe neurologic injury (SNI).

RESULTS

After matching, 2,224 infants were included. On-ECMO repair was associated with greater than 3-fold higher odds of mortality (OR 3.41, 95% CI: 2.84-4.09, p<0.01). The odds of SNI was also higher for on-ECMO repair (OR 1.49, 95% CI: 1.13-1.96, p<0.01). A sensitivity analysis was performed by including the length of ECMO as an additional matching variable. On-ECMO repair was still associated with higher odds of mortality (OR 2.38, 95% CI: 1.96-2.89, p<0.01). Results for SNI were similar but were no longer statistically significant (OR 1.33, 95% CI: 0.99-1.79, p=0.06).

CONCLUSIONS

Of the infants who can be liberated from ECMO and undergo CDH repair, there is a potential survival benefit for delaying CDH repair until after decannulation.

TYPE OF STUDY

Treatment Study LEVEL OF EVIDENCE: III.

Left ventricular cardiac output is a reliable predictor of extracorporeal life support in neonates with congenital diaphragmatic hernia

OBJECTIVE

Congenital diaphragmatic hernia (CDH) is a treatable condition but despite optimal management, some patients require extracorporeal life support (ECLS). This study evaluates the association of left ventricular (LV) cardiac output and the need for ECLS.

STUDY DESIGN

Single center, retrospective chart review from 1/1/2012 through 7/1/2018. Twenty-seven patients met criteria for evaluation with six patients (22%) requiring ECLS. Echocardiography was used to assess ventricular function.

RESULTS

There was a statistically significant decrease in LV cardiac index of 1.33 L /min/m² vs 1.80 L /min/m² (p = 0.04) for patients requiring ECLS and non-ECLS, respectively. There was no difference between the 2 groups with regards to vasoactive medication use, surfactant use, iNO use, severity of pulmonary hypertension, or right ventricular (RV) function.

CONCLUSION

In newborns with CDH, decreased LV cardiac output is more strongly associated with need for ECLS than severity of pulmonary hypertension or RV dysfunction.

Management preferences in ECMO mode for congenital diaphragmatic hernia

PURPOSE

The purpose of this study was to identify management preferences that may exist in the care of infants with CDH receiving ECMO with emphasis on VV-ECMO.

METHODS

A survey was created to measure treatment preferences regarding ECMO use in CDH. The survey was distributed to all APSA and ELSO/Euro-ELSO members via e-mail. Survey results were summarized using descriptive statistics.

RESULTS

The survey had 230 respondents. The survey participants were surgeons (75%), neonatologists/intensivists (23%), and "other" (2%). The mean annual center volume was 11.6(±9.6) CDH cases, and the average number treated with ECMO was 4.5 (±6.4) cases/yr. The most agreed upon criteria for ECMO initiation were preductal O₂ saturation <80% refractory to ventilator manipulation and medical therapy (89%), oxygenation index >40 (80%), severe air-leak (79%), and mixed acidosis (75%). Over 60% of respondents agreed the VV-ECMO would be optimum for average risk neonates. However, this preference diminished as the pre-ECMO level of cardiac support increased. When asked about why each respondent would choose VA-ECMO over VV-ECMO, the responses varied significantly between surgeons and non-surgeons.

CONCLUSION

While there seem to be areas of consensus among practitioners, such as criteria for initiation of ECMO, this survey revealed substantial variation in individual practice patterns regarding the use of ECMO for CDH.

TYPE OF STUDY

Qualitative, Survey.

LEVEL OF EVIDENCE

IV.

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.

Generation of a Functioning and Self-Renewing Diaphragmatic Muscle Construct

Surgical repair of large muscular defects requires the use of autologous graft transfer or prosthetic material. Naturally derived matrices are biocompatible materials obtained by tissue decellularization and are commonly used in clinical practice. Despite promising applications described in the literature, the use of acellular matrices to repair large defects has been only partially successful, highlighting the need for more efficient constructs. Scaffold recellularization by means of tissue engineering may improve not only the structure of the matrix, but also its ability to functionally interact with the host. The development of such a complex construct is challenging, due to the complexity of the native organ architecture and the difficulties in recreating the cellular niche with both proliferative and differentiating potential during growth or after damage. In this study, we tested a mouse decellularized diaphragmatic extracellular matrix (ECM) previously described by our group, for the generation of a cellular skeletal muscle construct with functional features. The decellularized matrix was stored using different conditions to mimic the off‐the‐shelf clinical need. Pediatric human muscle precursors were seeded into the decellularized scaffold, demonstrating proliferation and differentiation capability, giving rise to a functioning three‐dimensional skeletal muscle structure. Furthermore, we exposed the engineered construct to cardiotoxin injury and demonstrated its ability to activate a regenerative response in vitro promoting cell self‐renewal and a positive ECM remodeling. Functional reconstruction of an engineered skeletal muscle with maintenance of a stem cell pool makes this a promising tool toward future clinical applications in diaphragmatic regeneration. stem cells translational medicine2019;8:858&869

Preoperative cardiopulmonary evaluation in specific neonatal surgery

Preoperative assessment of surgical neonates often relates to issues of prematurity, low birth weight, or associated malformations. This review explores the preoperative cardiopulmonary evaluation in specific newborn surgical populations, the role of echocardiography in congenital diaphragmatic hernia perioperative management, the impact of bronchopulmonary dysplasia in the ex-preterm surgical neonate and a brief discussion on the risk of general anesthesia and specific anesthetic considerations for any surgical neonate. Newborns with congenital anomalies requiring early general surgical intervention should have an assessment for congenital heart disease. In the asymptomatic neonate, a thorough physical exam may be sufficient preoperatively. Neonates born with esophageal atresia or anorectal malformations should have a full evaluation for VACTERL associations. Initial echocardiography in congenital diaphragmatic hernia is used to evaluate anatomy, but there is emerging evidence to suggest the use of echocardiography in the ongoing surveillance of CDH to influence the timing of surgical intervention. Bronchopulmonary dysplasia is present in up to 40% of ex-premature neonates and increases the risk of postoperative apneas and need for ventilatory support. However, all surgical neonates have an increased risk of post-operative apneas, and the need for surgical intervention should be balanced with the risk of general anesthesia.

Extracorporeal Membrane Oxygenation in Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) is characterized by failure of diaphragmatic development with lung hypoplasia and persistent pulmonary hypertension of the newborn (PPHN). If conventional treatment with gentle ventilation and optimized vasoactive medication fails, extracorporeal membrane oxygenation (ECMO) may be considered. The benefits of ECMO in CDH are still controversial, since there are only few randomized trials demonstrating the advantages of this therapeutic option. At present, there is no precise prenatal and/or early postnatal prognostication parameter to predict reversibility of PPHN in CDH patients. Indications for initiating ECMO include either respiratory or circulatory parameters, which are also undergoing continuous refinement. Centers with higher case numbers and the availability of ECMO published promising survival rates, but data on long-term results, including morbidity and quality of life, are rare. Survival might be influenced by the timing of ECMO initiation and the timing of surgical repair. In this regard a trend toward early initiation of ECMO and early surgery on ECMO exists. The results concerning the cannulation modes are similar and a consensus on time limit for ECMO runs does not exist. The use of ECMO in CDH will continue to be evaluated, and prospective randomized trials and registry network are necessary to help answering the addressed questions of patient selection and management.

Relationship between volume and outcome for congenital diaphragmatic hernia: a systematic review protocol

BACKGROUND

Congenital diaphragmatic hernia is a rare and life-threatening anomaly that occurs during fetal development and results in an incomplete or incorrect formation of the diaphragm. Surgical therapy of the diaphragm should be performed after clinical stabilization of the neonate. Higher hospital or surgeon volume has previously been found to be associated with better clinical outcomes for different especially high-risk, low-volume procedures. Therefore, we aim to examine the relationship between hospital or surgeon volume and outcomes for congenital diaphragmatic hernia.

METHODS

This systematic review protocol has been designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol. We will perform a systematic literature search in MEDLINE, Embase, CINAHL and Biosis Previews without applying any limitations. In addition, we will search for relevant conference abstracts. We will screen titles and abstracts of retrieved studies, obtain potentially relevant full texts, and assess the eligibility of those full texts against our inclusion criteria. We will include comparative studies analyzing the relationship between hospital or surgeon volume and clinical outcomes. We will systematically assess risk of bias of included studies and extract data on the study design, patient characteristics, case-mix adjustments, statistical methods, hospital and surgeon volume, and outcomes into standardized tables. Title and abstract screening, full-text screening, critical appraisal, and data extraction of results will be conducted by two reviewers independently. Other data will be extracted by one reviewer and checked for accuracy by a second one. Any disagreements will be resolved by discussion. We will not perform a meta-analysis as we expect included studies to be clinically and methodologically very diverse. We will synthesize findings from primary studies in a structured narrative way and using GRADE.

DISCUSSION

Given the lack of a comprehensive summary of findings on the relationship between hospital or surgeon volume and outcomes for congenital diaphragmatic hernia, this systematic review will put things right. Results can be used to inform decision makers or clinicians and to adapt medical care.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO ( CRD42018090231 ).

Early population-based outcomes of infants born with congenital diaphragmatic hernia

PURPOSE

This study aims to describe short-term outcomes of live-born infants with congenital diaphragmatic hernia (CDH) and to identify prognostic factors associated with early mortality.

DESIGN

A prospective population cohort study was undertaken between April 2009 and September 2010, collecting data on live-born infants with CDH from all 28 paediatric surgical centres in the UK and Ireland using an established surgical surveillance system. Management and outcomes are described. Prognostic factors associated with death before surgery are explored.

RESULTS

Two hundred and nineteen live-born infants with CDH were reported within the data collection period. There were 1.5 times more boys than girls (n=133, 61%). Thirty-five infants (16%) died without an operation. This adverse outcome was associated with female sex (adjusted OR (aOR) 3.96, 95% CI 1.66 to 9.47), prenatal diagnosis (aOR 4.99, 95% CI 1.31 to 18.98), and the need for physiological support in the form of inotropes (aOR 9.96, 95% CI 1.19 to 83.25) or pulmonary vasodilators (aOR 4.09, 95% CI 1.53 to 10.93). Significant variation in practice existed among centres, and some therapies potentially detrimental to infant outcomes were used, including pulmonary surfactant in 45 antenatally diagnosed infants (34%). Utilisation of extracorporeal membrane oxygenation was very low compared with published international studies (n=9/219, 4%). Postoperative 30-day survival was 98% for 182 infants with CDH who were adequately physiologically stabilised and underwent surgery.

CONCLUSION

This is the first British Isles population-based study reporting outcome metrics for infants born with CDH. 16% of babies did not survive to undergo surgery. Factors associated with poor outcome included female sex and prenatal diagnosis. Early postoperative survival in those who underwent surgical repair was excellent.

Controversies in extracorporeal membrane oxygenation (ECMO) utilization and congenital diaphragmatic hernia (CDH) repair using a Delphi approach: from the American Pediatric Surgical Association Critical Care Committee (APSA-CCC)

PURPOSE

Review current practices and expert opinions on contraindications to extracorporeal membrane oxygenation (ECMO) in congenital diaphragmatic hernia (CDH) and contraindications to repair of CDH following initiation of ECMO.

METHODS

Modified Delphi method was employed to achieve consensus among members of the American Pediatric Surgical Association Critical Care Committee (APSA-CCC).

RESULTS

Overall response rate was 81% including current and former members of the APSA-CCC. An average of 5-15 CDH repairs were reported annually per institution; 26-50% of patients required ECMO. 100% of respondents would not offer ECMO to a patient with a complex or unrepairable cardiac defects or lethal chromosomal abnormality; 94.1% would not in the setting of severe intracranial hemorrhage (ICH). 76.5% and 72.2% of respondents would not offer CDH repair to patients on ECMO with grade III-IV ICH or new diagnosis of lethal genetic or metabolic abnormalities, respectively. There was significant variability in whether or not to repair CDH if unable to wean from ECMO at 4-5 weeks.

CONCLUSIONS

Significant variability in practice pattern and opinions exist regarding contraindications to ECMO and when to offer repair of CDH for patients on ECMO. Ongoing work to evaluate outcomes is needed to standardize management and minimize potentially futile interventions.

LEVEL OF EVIDENCE

V (expert opinion).

Outcomes of infants with congenital diaphragmatic hernia treated with venovenous versus venoarterial extracorporeal membrane oxygenation: A propensity score approach

PURPOSE

Previous studies comparing extracorporeal membrane oxygenation (ECMO) modality for congenital diaphragmatic hernia (CDH) have not accounted for confounding by indication. We therefore hypothesized that using a propensity score (PS) approach to account for selection bias may identify outcome differences based on ECMO modality for infants with CDH.

METHODS

We utilized ELSO Registry data (2000-2016). Patients with CDH were divided to either venoarterial (VA) or venovenous (VV) ECMO. Patients were matched by PS to control for nonrandom treatment assignment. Subgroup analyses were conducted based on timing of CDH repair relative to ECMO. Primary analysis was the "intent-to-treat" cohort based on the initial ECMO mode. Mortality was the primary outcome, and severe neurologic injury (SNI) was a secondary outcome.

RESULTS

PS matching (3:1) identified 3304 infants (VA = 2470, VV = 834). In the main group, mortality was not different between VA and VV ECMO (OR = 1.01, 95% CI: 0.86-1.18) and there was no difference in SNI between VA and VV (OR = 0.80; 95% CI: 0.63-1.01). For the pre-ECMO CDH repair subgroup, 175 VA cases were matched to 70 VV. In these neonates, mortality was higher for VV compared to VA (OR = 2.10, 95% CI: 1.19-3.69), without any difference in SNI (OR = 1.48; 95% CI: 0.59-3.71). For the subgroup that did not have pre-ECMO CDH repair, 2030 VA cases were matched to 683 VV cases. In this subgroup, VV was associated with 27% lower risk of SNI relative to VA (OR = 0.73, 95% CI: 0.56-0.95) without any difference in mortality (OR = 0.94, 95% CI: 0.79-1.11).

CONCLUSION

This study revalidates that ECMO mode does not significantly affect mortality or SNI in infants with CDH. In the subset of infants who require pre-ECMO CDH repair, VA favors survival, whereas, in the subgroup of infants that did not have pre-ECMO CDH repair, VV favors lower rates of SNI. We conclude that neither mode appears consistently superior across all situations, and clinical judgment should remain a multifactorial decision.

LEVEL OF EVIDENCE

Level III.

Hemoglobin oxygen saturation targets in the neonatal intensive care unit: Is there a light at the end of the tunnel? 1

The optimal oxygenation target needed to prevent the extremes of hypoxia and oxygen toxicity in premature and sick newborns has been the subject of much research and debate. The advent of the pulse oximeter has allowed the continuous monitoring of oxyhemoglobin saturation and the delivery of oxygen with greater precision. Well-run, large clinical trials to determine the safest oxygen concentration have led to several revisions in guidelines for neonatal care. However, monitoring of oxyhemoglobin saturation has its limitations and does not provide a comprehensive assessment of tissue oxygenation. To identify optimal oxygen therapy, various other factors (partial pressure of arterial carbon dioxide, hemoglobin concentration, blood pH, and tissue metabolic demand) that influence perfusion and tissue oxygenation need to be considered.

Improving outcome in congenital diaphragmatic hernia - experience of a tertiary center without ECMO

BACKGROUND

Congenital diaphragmatic hernia (CDH) has a high mortality rate, representing a therapeutic challenge. Prenatal diagnosis (PND) is essential in defining optimal perinatal strategy, particularly delivery planning. Hospital Pediátrico de Coimbra is the referral centre for all neonatal surgery, particularly CDH, for the central region of Portugal. The aim was to evaluate clinical management and outcome of newborns with CDH.

METHODS

An exploratory retrospective study made up of newborns admitted to PICU with CDH was undertaken between January 1995 and December 2014. Two groups were formed based on their year of admission: group A (1995- 2004) and group B (2005- 2014) and were compared.

RESULTS

The mean birth weight of the 69 newborns admitted was 2.762 ± 696 g; the median of the gestational age was 38 weeks. Associated malformations were observed in 28 (40.5%) and 15 (21.7%) had a right-sided diaphragm defect. The global mortality was 13.0%; in group A was significantly higher than in group B (22.2 vs 3.0%; p = 0.029). A reduction in mortality throughout the years was confirmed after adjusting for POS score (OR = 0.77; 95% CI: 0.62- 0.96, p = 0.021). PND was made in 30.6% of cases in the group A and 66.7% in the group B (p = 0.03). Tertiary perinatal hospital birth was achieved in 60% of newborns in the group A versus 84.8% in group B (p = 0.022). Maximum fraction of inspired oxygen showed a statistically significant difference between the two study groups (60% vs 40%; p = 0.009).

CONCLUSIONS

A significant decrease in mortality was observed throughout the study. The authors highlight the increase in prenatal diagnosis and an improvement in perinatal care with planning delivery as important contributors to these results.

Extracorporeal Membrane Oxygenation (ECMO) Risk Stratification in Newborns with Congenital Diaphragmatic Hernia (CDH)

BACKGROUND

A means for early postnatal stratification of ECMO risk in CDH newborns could be used to comparatively assess the utilization and outcomes of ECMO use between centers. While multiple CDH mortality risk calculators are available, no validated tool exists specifically for prediction of ECMO use. The purpose of this study was to derive and validate an ECMO risk stratification model.

METHODS

The study population was obtained from CDH Study Group registry for the period between 2007 and 2016. Only centers offering ECMO were included. The cohort was restricted to ECMO candidates and then divided into derivation and validation sets. Using all relevant perinatal predictors in the registry, univariate analysis was performed for the composite outcome of ECMO use or death without ECMO use. The model was derived using the derivation cohort with multivariable logistic regression and automatic stepwise forward selection (P < 0.05 for qualifying variables), and a c-statistic was obtained. The model was then tested on the validation cohort. Sample reuse validation and bootstrap validation were performed. The validated model was then tested for accuracy on CDH subgroups.

RESULTS

There were 1992 patients in the derivation cohort. Four significant variables were identified in the final ECMO risk model: 1-min and 5-min Apgar scores and highest and lowest post-ductal partial pressure of CO2 during the first 24 h of life. The model c-statistic was 0.824 which was confirmed with cross-validation and bootstrap optimism correction. The validation cohort c-statistic was 0.823 (N = 993). The model had good discrimination for left and right CDH, inborn and outborn patients, patients born before and after 2011, and high and low volume centers. The model performed significantly better for postnatally diagnosed patients.

CONCLUSIONS

This study represents proof-of-concept that a risk model can accurately estimate the probability of ECMO use in CDH newborns. This stratification could assist centers as a metric for assessment of ECMO usage and outcomes. Refinement and prospective validation of this model should be carried out prior to clinical application.

LEVEL OF EVIDENCE

3.

Lung function and pulmonary artery blood flow following prenatal maternal retinoic acid and imatinib in the nitrofen model of congenital diaphragmatic hernia

BACKGROUND

Lung and pulmonary vascular maldevelopment in congenital diaphragmatic hernia (CDH) results in significant morbidity and mortality. Retinoic acid (RA) and imatinib have been shown to improve pulmonary morphology following prenatal administration in the rat nitrofen-induced CDH model. It remains unclear if these changes translate into improved function. We evaluated the effect of prenatal RA and imatinib on postnatal lung function, structure, and pulmonary artery (PA) blood flow in the rat CDH model.

METHODS

Olive oil or nitrofen was administered alone or in combination with RA or imatinib to pregnant rats. Pups were assessed for PA blood flow by ultrasound and pulmonary function/morphology following delivery, intubation, and short-term ventilation.

RESULTS

Neither RA nor imatinib had a negative effect on lung and body growth. RA accelerated lung maturation indicated by increased alveoli number and thinner interalveolar septa and was associated with decreased PA resistance and improved oxygenation. With the exception of a decreased PA pulsatility index, no significant changes in morphology and pulmonary function were noted following imatinib.

CONCLUSION

Prenatal treatment with RA but not imatinib was associated with improved pulmonary morphology and function, and decreased pulmonary vascular resistance. This study highlights the potential of prenatal pharmacologic therapies, such as RA, for management of CDH.

Fetal lung transcriptome patterns in an ex vivo compression model of diaphragmatic hernia

BACKGROUND

The purpose of this study was to employ a novel ex vivo lung model of congenital diaphragmatic hernia (CDH) to determine how a mechanical compression affects early pulmonary development.

METHODS

Day-15 whole fetal rat lungs (n = 6-12/group) from nitrofen-exposed and normal (vehicle only) dams were explanted and cultured ex vivo in compression microdevices (0.2 or 0.4 kPa) for 16 h to mimic physiologic compression forces that occur in CDH in vivo. Lungs were evaluated with significance set at P < 0.05.

RESULTS

Nitrofen-exposed lungs were hypoplastic and expressed lower levels of surfactant protein C at baseline. Although compression alone did not alter the α-smooth muscle actin (ACTA2) expression in normal lungs, nitrofen-exposed lungs had significantly increased ACTA2 transcripts (0.2 kPa: 2.04 ± 0.15; 0.4 kPa: 2.22 ± 0.11; both P < 0.001). Nitrofen-exposed lungs also showed further reductions in surfactant protein C expression at 0.2 and 0.4 kPa (0.53 ± 0.04, P < 0.01; 0.69 ± 0.23, P < 0.001; respectively). Whereas normal lungs exposed to 0.2 and 0.4 kPa showed significant increases in periostin (POSTN), a mechanical stress-response molecule (1.79 ± 0.10 and 2.12 ± 0.39, respectively; both P < 0.001), nitrofen-exposed lungs had a significant decrease in POSTN expression (0.4 kPa: 0.67 ± 0.15, P < 0.001), which was confirmed by immunohistochemistry.

CONCLUSIONS

Collectively, these pilot data in a model of CDH lung hypoplasia suggest a primary aberration in response to mechanical stress within the nitrofen lung, characterized by an upregulation of ACTA2 and a downregulation in SPFTC and POSTN. This ex vivo compression system may serve as a novel research platform to better understand the mechanobiology and complex regulation of matricellular dynamics during CDH fetal lung development.

Evaluating the utility of the "late ECMO repair": a congenital diaphragmatic hernia study group investigation

PURPOSE

Optimal timing of congenital diaphragmatic hernia (CDH) repair in patients requiring extracorporeal membrane oxygenation (ECMO) remains controversial. The "late ECMO repair" is an approach where the patient, once deemed stable for decannulation, is repaired while still on ECMO to enable expeditious return to ECMO if surgery induces instability. The goal of this study was to investigate the potential benefit of this approach by evaluating the rate of return to ECMO after repair.

METHODS

The CDH Study Group database was used to analyze CDH patients requiring ECMO support. The primary outcome was return to ECMO within 72 h of CDH repair among those repaired following ECMO decannulation ("post-ECMO" patients). Secondary outcomes were death within 72 h of repair and cumulative death and return to ECMO rate.

RESULTS

A total of 668 patients were repaired post-ECMO decannulation. Six patients (0.9%) in the post-ECMO group required return to ECMO within 72 h of surgery and a total of 19 (2.8%) died or returned to ECMO within 72 h of surgery.

CONCLUSION

The rate of return to ECMO and death following CDH repair is extremely low and does not justify the risks inherent to "on-ECMO" repair. Patients stable to come off ECMO should undergo repair after decannulation.

Treatment of rat congenital diaphragmatic hernia with sildenafil and NS-304, selexipag's active compound, at the pseudoglandular stage improves lung vasculature

Patients with congenital diaphragmatic hernia (CDH) often suffer from severe pulmonary hypertension, and the choice of current vasodilator therapy is mostly based on trial and error. Because pulmonary vascular abnormalities are already present early during development, we performed a study to modulate these pulmonary vascular changes at an early stage during gestation. Pregnant Sprague-Dawley rats were treated with nitrofen at day 9.5 of gestation (E9.5) to induce CDH in the offspring, and subsequently, the phosphodiesterase-5 inhibitor sildenafil and/or the novel prostaglandin-I receptor agonist selexipag (active compound NS-304) were administered from E17.5 until E20.5. The clinical relevant start of the treatment corresponds to week 20 of gestation in humans, when CDH is usually detected by ultrasound. CDH pups showed increased density of air saccules that was reverted after the use of only sildenafil. The pulmonary vascular wall was thickened, and right ventricular hypertrophy was present in the CDH group and improved both after single treatment with sildenafil or selexipag, whereas the combination therapy with both compounds did not have additive value. In conclusion, antenatal treatment with sildenafil improved airway morphogenesis and pulmonary vascular development, whereas selexipag only acted positively on pulmonary vascular development. The combination of both compounds did not act synergistically, probably because of a decreased efficiency of both compounds caused by cytochrome- P450 3A4 interaction and induction. These new insights create important possibilities for future treatment of pulmonary vascular abnormalities in CDH patients already in the antenatal period of life.

Acquired Infection and Antimicrobial Utilization During Initial NICU Hospitalization in Infants With Congenital Diaphragmatic Hernia

BACKGROUND

In addition to substantial medical and surgical intervention, neonates with congenital diaphragmatic hernia often have concurrent concerns for acquired infection. However, few studies focus on infection and corresponding antimicrobial utilization in this population.

METHODS

The Children's Hospital Neonatal Database was queried for congenital diaphragmatic hernia infants hospitalized from January 2010 to February 2016. Patient charts were linked to the Pediatric Health Information Systems database. Descriptive clinical data including delivery history, cultures sent, diagnosed infection, antimicrobial use and outcomes were reported.

RESULTS

A total of 1085 unique patients were identified after data linkages; 275 (25.3%) were born at <37 weeks' gestation. Bacteremia at delivery (2/1085) and in the first 7 days of life (8/1085) was less common than later infection, but 976 patients (89.9%) were treated with antibiotics. Median number of days on antibiotics was 6 [3,11] for those without a documented infection and 21 [13,36] for those with positive cultures. Incidence of urinary tract infection, bacteremia and pneumonia increased significantly over time and was most common after 28 days. Antibiotic use, conversely, decreased over time (92% of infants in week 1 to 44% in week 4 and beyond).

CONCLUSIONS

Although culture positivity increased with age, risk of these selected infections was relatively low for a population in neonatal intensive care unit. An important mismatch is observed between culture negativity and high rates of antibiotic utilization. These data identify opportunities for antibiotic stewardship quality improvement programs.

Role of ECMO in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is typified morphologically by failure of diaphragmatic development with accompanying lung hypoplasia and persistent pulmonary hypertension of the newborn (PPHN). Patients who have labile physiology and low preductal saturations despite optimal ventilatory and inotropic support may be considered for extracorporeal membrane oxygenation (ECMO). Systematic reviews into the benefits of ECMO in CDH concluded that any benefit is unclear. Few randomised trials exist to demonstrate clear benefit and guide management. However, ECMO may have its uses in those that have reversibility of their respiratory disease. A few centres and networks have demonstrated an increase in survival rate by post hoc analysis (based on a difference in referral patterns with the availability of ECMO) in their series. One issue may be that of careful patient selection with regard to reversibility of pathophysiology. At present, there is no single test or prognostication that predicts reversibility of PPHN and criteria for referral for ECMO is undergoing continued refinement. Overall survival is similar between cannulation modes. There is no consensus on the time limit for ECMO runs. The optimal timing of surgery for patients on ECMO is difficult to definitively establish, but it seems that repair at an early stage (with careful perioperative management) is becoming less of a taboo, and may improve outcome and help with either coming off ECMO or decisions on withdrawal later. The provision of ECMO will continue to be evaluated, and prospective randomised trial are needed to help answer question of patient selection and management.

Ventricular Performance is Associated with Need for Extracorporeal Membrane Oxygenation in Newborns with Congenital Diaphragmatic Hernia

OBJECTIVE

To compare echocardiography (ECHO) findings of patients with congenital diaphragmatic hernia (CDH) who required extracorporeal membrane oxygenation (ECMO) to non-ECMO treated patients.

STUDY DESIGN

We reviewed clinical and ECHO data of newborns with CDH born between 2009 and 2016. Exclusions included major anomalies, genetic syndromes, or no ECHO prior to ECMO. Pulmonary hypertension was assessed by ductal shunting and tricuspid regurgitant jet. Speckle tracking echocardiography (STE) assessed function by quantifying deformation.

RESULTS

Patients with CDH (15 ECMO and 29 with no ECMO) were analyzed. Most patients had a left CDH (88.6%). Age at ECHO was similar between groups. Outborn status (P = .009) and liver position (P = .009) were associated with need for ECMO. Compared with non-ECMO patients, patients who required ECMO had significantly decreased left and right ventricular function by both conventional and STE measures, as well as decreased right and left ventricular output. The right ventricular eccentricity index was higher in ECMO vs non-ECMO patients (2.2 vs 1.8, P = .02). There was no difference in pulmonary hypertension between CDH groups.

CONCLUSIONS

Need for ECMO was associated with decreased left and right ventricular function, as assessed by standard and STE measures. There was no difference in pulmonary hypertension between non ECMO and ECMO patients. Abnormal cardiac function may explain nonresponse to pulmonary vasodilators in patients with CDH. Management strategies to improve cardiac function may reduce the need for ECMO in newborns with CDH.

Changes in vasoactive pathways in congenital diaphragmatic hernia associated pulmonary hypertension explain unresponsiveness to pharmacotherapy

BACKGROUND

Patients with congenital diaphragmatic hernia (CDH) have structural and functional different pulmonary vessels, leading to pulmonary hypertension. They often fail to respond to standard vasodilator therapy targeting the major vasoactive pathways, causing a high morbidity and mortality. We analyzed whether the expression of crucial members of these vasoactive pathways could explain the lack of responsiveness to therapy in CDH patients.

METHODS

The expression of direct targets of current vasodilator therapy in the endothelin and prostacyclin pathway was analyzed in human lung specimens of control and CDH patients.

RESULTS

CDH lungs showed increased expression of both ETA and ETB endothelin receptors and the rate-limiting Endothelin Converting Enzyme (ECE-1), and a decreased expression of the prostaglandin-I₂ receptor (PTGIR). These data were supported by increased expression of both endothelin receptors and ECE-1, endothelial nitric oxide synthase and PTGIR in the well-established nitrofen-CDH rodent model.

CONCLUSIONS

Together, these data demonstrate aberrant expression of targeted receptors in the endothelin and prostacyclin pathway in CDH already early during development. The analysis of this unique patient material may explain why a significant number of patients do not respond to vasodilator therapy. This knowledge could have important implications for the choice of drugs and the design of future clinical trials internationally.

Congenital diaphragmatic hernias: from genes to mechanisms to therapies

Congenital diaphragmatic hernias (CDHs) and structural anomalies of the diaphragm are a common class of congenital birth defects that are associated with significant morbidity and mortality due to associated pulmonary hypoplasia, pulmonary hypertension and heart failure. In ∼30% of CDH patients, genomic analyses have identified a range of genetic defects, including chromosomal anomalies, copy number variants and sequence variants. The affected genes identified in CDH patients include transcription factors, such as GATA4, ZFPM2, NR2F2 and WT1, and signaling pathway components, including members of the retinoic acid pathway. Mutations in these genes affect diaphragm development and can have pleiotropic effects on pulmonary and cardiac development. New therapies, including fetal endoscopic tracheal occlusion and prenatal transplacental fetal treatments, aim to normalize lung development and pulmonary vascular tone to prevent and treat lung hypoplasia and pulmonary hypertension, respectively. Studies of the association between particular genetic mutations and clinical outcomes should allow us to better understand the origin of this birth defect and to improve our ability to predict and identify patients most likely to benefit from specialized treatment strategies.

Risk stratification for congenital diaphragmatic hernia by factors within 24 h after birth

OBJECTIVE

To establish a simple risk stratification system for patients with congenital diaphragmatic hernia (CDH) based on postnatal information within 24 h after birth.

STUDY DESIGN

A multi-institutional retrospective cohort study was conducted including 348 neonates who had isolated CDH born between 2006 and 2010. Based on the two most powerful variables for 90-day survival selected by multivariate analyses, a risk stratification system was established.

RESULTS

Multiple logistic regression analysis identified two adverse prognostic factors: an Apgar score at 1 min (Ap1) of 0-4 (odds ratio (OR) 3.3, P=0.004), and a best oxygenation index (OI) ⩾8.0 (OR 11.4, P<0.001). Based on a combinations of these two factors, patients were classified into three risk categories. The 90-day survival rates in categories 1-3 were 100, 88 and 52%, respectively (P<0.001).

CONCLUSION

Our simple risk stratification system based on Ap1 and best OI was capable of predicting mortality well.