Genomic Contributors to Esophageal Atresia and Tracheoesophageal Fistula: A 12 Year Retrospective Review.

OBJECTIVE: To evaluate genetic testing utilization and diagnostic yield in infants with esophageal atresia (EA)/tracheoesophageal fistula (TEF) over the past 12 years to inform future practices and individualize prognostication and management. STUDY DESIGN: A retrospective cohort study was performed for all infants with EA or EA/TEF hospitalized between January 2011 and January 2023 at a quaternary children's hospital. For each infant, demographic information, prenatal and postnatal history, and genetic testing were reviewed. RESULTS: There were 212 infants who were classified as follows: 1) complex/syndromic with EA/TEF plus an additional major anatomic anomaly (n = 114, of which 74 met VACTERL criteria); 2) isolated/nonsyndromic EA/TEF (n = 88) and 3) isolated/nonsyndromic EA (n = 10). A range of genetic tests were sent with varying diagnostic rates including karyotype analysis in 12 (all with complex/syndromic phenotypes and all positive), chromosomal microarray analysis in 189 (114 of whom were complex/syndromic with an overall diagnostic rate of 3/189), single gene testing for CHD7 in 18 (4 positive), and exome analysis in 37 complex/syndromic patients (8 positive). CONCLUSIONS: EA/TEF with and without additional anomalies is genetically heterogeneous with a broad range of associated phenotypes. While the genetic etiology of EA/TEF with or without VACTERL remains largely unknown, genome wide testing (exome or genome) including copy number analysis is recommended over chromosomal microarray testing. We anticipate that expanded genetic/genomic testing modalities such as RNA sequencing and tissue specific molecular testing are needed in this cohort to improve our understanding of the genomic contributors to EA/TEF.

The Delivery Room Resuscitation of Infants with Congenital Diaphragmatic Hernia Treated with Fetoscopic Endoluminal Tracheal Occlusion: Beyond the Balloon.

INTRODUCTION: Randomized controlled trials found that fetoscopic endoluminal tracheal occlusion (FETO) resulted in increased fetal lung volume and improved survival for infants with isolated, severe left-sided congenital diaphragmatic hernia (CDH). The delivery room resuscitation of these infants is particularly unique, and the specific delivery room events are largely unknown. The objective of this study was to compare the delivery room resuscitation of infants treated with FETO to standard of care (SOC) and describe lessons learned. METHODS: Retrospective single-center cohort study of infants treated with FETO compared to infants who met FETO criteria during the same period but who received SOC. RESULTS: FETO infants were more likely to be born prematurely with 8/12 infants born <35 weeks gestational age compared to 3/35 SOC infants. There were 5 infants who required emergent balloon removal (2 ex utero intrapartum treatment and 3 tracheoscopic removal on placental bypass with delayed cord clamping) and 7 with prenatal balloon removal. Surfactant was administered in 6/12 FETO (50%) infants compared to 2/35 (6%) in the SOC group. Extracorporeal membrane oxygenation use was lower at 25% and survival was higher at 92% compared to 60% and 71% in the SOC infants, respectively. CONCLUSION: The delivery room resuscitation of infants treated with FETO requires thoughtful preparation with an experienced multidisciplinary team. Given increased survival, FETO should be offered to infants with severe isolated left-sided CDH, but only in high-volume centers with the experience and capability of removing the balloon, emergently if needed. The neonatal clinical team must be skilled in managing the unique postnatal physiology inherent to FETO where effective interdisciplinary teamwork is essential. Empiric and immediate surfactant administration should be considered in all FETO infants to lavage thick airway secretions, particularly those delivered <48 h after balloon removal.

Prenatal treprostinil improves pulmonary arteriolar hypermuscularization in the rabbit model of congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) is a congenital malformation characterized by pulmonary hypoplasia, pulmonary hypertension, and cardiac dysfunction. Pulmonary hypertension represents the major cause of neonatal mortality and morbidity. Prenatal diagnosis allows assessment of severity and selection of foetal surgery candidates. We have shown that treprostinil, a prostacyclin analogue with an anti-remodelling effect, attenuates the relative hypermuscularization of the pulmonary vasculature in rats with nitrofen-induced CDH. Here we confirm these observations in a large animal model of surgically-created CDH. In the rabbit model, subcutaneous maternal administration of treprostinil at 150 ng/kg/min consistently reached target foetal concentrations without demonstrable detrimental foetal or maternal adverse effects. In pups with CDH, prenatal treprostinil reduced pulmonary arteriolar proportional medial wall thickness and downregulated inflammation and myogenesis pathways. No effect on alveolar morphometry or lung mechanics was observed. These findings provide further support towards clinical translation of prenatal treprostinil for CDH.

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.

Prenatally Diagnosed Large Lung Lesions: Timing of Resection and Perinatal Outcomes.

INTRODUCTION: Fetuses with large lung lesions including congenital cystic adenomatoid malformations (CCAMs) are at risk for cardiopulmonary compromise. Prenatal maternal betamethasone and cyst drainage for micro- and macrocystic lesions respectively have improved outcomes yet some lesions remain large and require resection before birth (open fetal surgery, OFS), at delivery via an Ex Utero Intrapartum Treatment (EXIT), or immediately post cesarean section (section-to-resection, STR). We sought to compare prenatal characteristics and outcomes in fetuses undergoing OFS, EXIT, or STR to inform decision-making and prenatal counseling. METHODS: A single institution retrospective review was conducted evaluating patients undergoing OFS, EXIT, or STR for prenatally diagnosed lung lesions from 2000 to 2021. Specimens were reviewed by an anatomic pathologist. Lesions were divided into "CCAMs" (the largest pathology group) and "all lung lesions" since pathologic diagnosis is not possible during prenatal evaluation when care decisions are made. Prenatal variables included initial, greatest, and final CCAM volume-ratio (CVR), betamethasone use/frequency, cyst drainage, and the presence of hydrops. Outcomes included survival, ECMO utilization, NICU length of stay (LOS), postnatal nitric oxide use, and ventilator days. RESULTS: Sixty-nine percent (59 of 85 patients) of lung lesions undergoing resection were CCAMs. Among patients with pathologic diagnosis of CCAM, the initial, largest, and final CVRs were greatest in OFS followed by EXIT and STR patients. Similarly, the incidence of hydrops was significantly greater and the rate of hydrops resolution was lower in the OFS group. Although the rate of cyst drainage did not differ between groups, maternal betamethasone use varied significantly (OFS 60.0%, EXIT 100.0%, STR 74.3%; p = 0.0378). Notably, all OFS took place prior to 2014. There was no difference in survival, ventilator days, nitric oxide, NICU LOS, or ECMO between groups. In multiple variable logistic modeling, determinants of survival to NICU discharge among patients undergoing resection with a pathologic diagnosis of CCAM included initial CVR <3.5 and need for <3 maternal betamethasone doses. CONCLUSION: For CCAMs that remain large despite maternal betamethasone or cyst drainage, surgical resection via OFS, EXIT, or STR are viable options with favorable and comparable survival between groups. In the modern era there has been a shift from OFS and EXIT procedures to STR for fetuses with persistently large lung lesions. This shift has been fueled by the increased use of maternal betamethasone and introduction of a Special Delivery Unit during the study period and the appreciation of similar fetal and neonatal outcomes for STR vs. EXIT and OFS with reduced maternal morbidity associated with a STR. Accordingly, efforts to optimize multidisciplinary perinatal care for fetuses with large lung lesions are important to inform patient selection criteria and promote STR as the preferred surgical approach in the modern era. LEVEL OF EVIDENCE: Level IV.

Ethics Considerations Regarding Artificial Womb Technology for the Fetonate.

Since the early 1980's, with the clinical advent of in vitro fertilization resulting in so-called "test tube babies," a wide array of ethical considerations and concerns regarding artificial womb technology (AWT) have been described. Recent breakthroughs in the development of extracorporeal neonatal life support by means of AWT have reinitiated ethical interest about this topic with a sense of urgency. Most of the recent ethical literature on the topic, however, pertains not to the more imminent scenario of a physiologically improved method of neonatal care through AWT, but instead to the remote scenario of "complete ectogenesis" that imagines human gestation occurring entirely outside of the womb. This scoping review of the ethical literature on AWT spans from more abstract concerns about complete ectogenesis to more immediate concerns about the soon-to-be-expected clinical life support of what we term the fetal neonate or fetonate. Within an organizing framework of different stages of human gestational development, from conception to the viable premature infant, we discuss both already identified and newly emerging ethical considerations and concerns regarding AWT and the care of the fetonate.

Tube cecostomy versus appendicostomy for antegrade enemas in the management of fecal incontinence in children: A systematic review.

BACKGROUND: Few studies have directly compared between cecostomy and appendicostomy for the management of fecal incontinence in pediatric population. This systematic review of the literature describes outcomes and complications following both procedures. We also reviewed studies reporting impact on quality of life and patient satisfaction. METHODS: MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar were searched for chronic constipation pediatric patients who underwent cecostomy or appendicostomy. Two reviewers independently screened studies, extracted data, and assessed quality. RESULTS: An initial literature search retrieved 633 citations. After review of all abstracts, 40 studies were included in the final analysis, assessing a total of 2086 patients. The overall rate of complications was lower in the cecostomy group compared to the appendicostomy group (16.6% and 42.3%, respectively). Achievement of fecal continence and improvement in patient quality of life were found to be similar in both groups, however the need for revision of surgery was approximately 15% higher in the appendicostomy group. CONCLUSION: Cecostomy has less post procedural complications, however rates of patient satisfaction and impact on quality of life were similar following both procedures. LEVEL OF EVIDENCE: III.

Neurologic outcomes of the premature lamb in an extrauterine environment for neonatal development.

BACKGROUND/PURPOSE: Neurologic injury remains the most important morbidity of prematurity. Those born at the earliest gestational ages can face a lifetime of major disability. Perinatal insults result in developmental delay, cerebral palsy, and other profound permanent neurologic impairments. The EXTracorporeal Environment for Neonatal Development (EXTEND) aims to transition premature neonates through this sensitive period, but it's impact on neurologic development requires analysis. METHODS: Fetal sheep were maintained in a fluid-filled environment for up to 28 days. Physiologic parameters were measured continuously; tissues were subsequently fixed and preserved for myelin quantification, glial cell staining, and structural assessment via magnetic resonance. Surviving animals were functionally assessed. RESULTS: No evidence of fetal brain ischemia or white matter tract injury associated with the EXTEND system was detected, and the degree of myelination was regionally appropriate and consistent with age matched controls. No evidence of neurologic injury or immaturity was visible on magnetic resonance; animals that transitioned from the system had no persistent neurologic deficits. CONCLUSIONS: No evidence of major neurologic morbidity was found in animals supported on the EXTEND system, though more work needs to be done in order to verify its safety during critical periods of neurologic development.

Simple Approach to Increase Donor Hematopoietic Stem Cell Dose and Improve Engraftment in the Murine Model of Allogeneic In Utero Hematopoietic Cell Transplantation.

The rationale for in utero hematopoietic cell transplantation (IUHCT) rests on exploitation of normal events during hematopoietic and immunologic ontogeny to allow allogeneic hematopoietic engraftment without myeloablative conditioning.  Host hematopoietic competition is among the primary barriers to engraftment in IUHCT. In the murine model this can be partially overcome by delivery of larger donor cell doses, but volume is limiting. Enrichment of donor hematopoietic stem cells (HSCs) would seem to offer a more efficient approach, but such enriched populations have engrafted poorly in existing models of IUHCT. To increase HSC dose while maintaining the presence of accessory cells, we used a less stringent enrichment protocol of single-step lineage depleted cells alone (lin-) or in combination with whole donor bone marrow mononuclear cells. Our results confirm that increasing doses of HSCs in combination with bone marrow accessory cells can dramatically improve engraftment after IUHCT. This represents a practical and clinically applicable strategy to maximize the engraftment potential of the donor graft without risk of treatment-associated toxicity.

Technical feasibility of umbilical cannulation in midgestation lambs supported by the EXTra-uterine Environment for Neonatal Development (EXTEND).

EXTEND (EXTra-uterine Environment for Neonatal Development) is a novel system for supporting extremely premature infants that replicates in utero conditions by maintaining a sterile fluid environment and providing gas exchange via a pumpless arteriovenous oxygenator circuit connected to the umbilical vessels. Target gestational age (GA) for EXTEND support in human infants is 23-27 weeks, when immature lungs are most susceptible to injury in the setting of air ventilation. We previously demonstrated physiologic support of premature lambs cannulated at 105-117 days GA (lungs developmentally analogous to the 23-27 week GA human infant) for up to 28 days on EXTEND. In the present study, we sought to determine the technical feasibility of umbilical vessel cannulation in 85-96 days GA lambs delivered to EXTEND at weights equivalent to the 23-27 week GA human infant (500-850 g). Five preterm lambs were cannulated at 85-96 days GA (term 145 days) and supported on EXTEND for 4-7 days. All lambs underwent umbilical artery and umbilical vein cannulation. Circuit flows and pressures were monitored continuously, and blood gases were obtained at regular intervals for assessment of oxygen parameters. Systemic pH and lactate were measured at least once daily. Mean body weight at cannulation was 641 ± 71 g (range 480-850 g). All lambs were cannulated successfully (cannula size varied from 8 to 12 Fr), and mean survival on EXTEND was 140 ± 7 hours. Mean circuit flow was 213 ± 15 mL/kg*min, mean pH was 7.37 ± 0.01, and mean lactate was 1.6 ± 0.2 mmol/L. During the initial 120 hours after EXTEND cannulation, there were no significant differences between 85-96 days GA lambs and 105-117 days GA lambs in weight-adjusted circuit flows, oxygen delivery, pH, or lactate levels. This study demonstrates successful umbilical cord cannulation and adequate circuit flows and oxygen delivery in midgestation lambs size-matched to the 23-27 week GA human fetus, which represents an important step in the translation of EXTEND to clinical practice.

Erythropoietin Prevents Anemia and Transfusions in Extremely Premature Lambs Supported by an EXTrauterine Environment for Neonatal Development (EXTEND).

BACKGROUND: We recently developed an EXTrauterine Environment for Neonatal Development (EXTEND) that provides physiologic support for premature lambs. Here, we assess the efficacy of exogenous erythropoietin (EPO) to prevent anemia and transfusions on EXTEND. MATERIALS AND METHODS: Lambs were cannulated at 0.7 gestation and supported on EXTEND for up to 4 weeks. The lambs were divided into three groups: (1) No EPO, (2) Low EPO (300 U kg-1 per day), and (3) High EPO (800 U kg-1 per day). Daily hematocrit and weekly complete blood count were assessed. RESULTS: The mean percentage change in hematocrit from baseline was significantly different between the groups (No EPO -23.6 ± 7.8% vs. Low EPO -16.6 ± 6.4% vs. High EPO +2.6 ± 6.6%; p = 0.02). This occurred despite a greater median number of blood transfusions in the No EPO group (5 vs. 1 vs. 0; p = 0.02). EPO administration was associated with a higher mean corpuscular volume (MCV; p < 0.01) and reticulocyte count (p = 0.02). The High EPO group was comparable to in utero control fetuses with respect to hematocrit (p = 0.49), MCV (p = 0.24), and reticulocyte count (p = 0.68). CONCLUSIONS: EPO (800 U kg-1 per day) prevents anemia, eliminates transfusions, and restores normal red blood cell indices in premature lambs supported by EXTEND.

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

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is commonly required in neonates with congenital diaphragmatic hernia (CDH) complicated by pulmonary hypertension (PH). ECMO carries significant risk, and is contraindicated in the setting of extreme prematurity or intracranial hemorrhage. Pumpless arteriovenous ECMO (P-ECMO) may represent an alternative for respiratory support. The present study summarizes our initial experience with P-ECMO in a lamb model of CDH. STUDY DESIGN: Surgical creation of CDH was performed at 65-75days' gestation. At term (135-145days), lambs were delivered into the P-ECMO circuit. Three animals were maintained on a low-heparin infusion protocol (target ACT 160-180) and three animals were maintained with no systemic heparinization. RESULTS: Animals were supported by the circuit for 380.7 +/- 145.6h (range, 102-504h). Circuit flow rates ranged from 97 to 208ml/kg/min, with adequacy of organ perfusion demonstrated by stable serum lactate levels (3.0 +/- 1.7) and pH (7.4 +/- 0.3). Necropsy demonstrated no evidence of thrombogenic complications. CONCLUSION: Pumpless extracorporeal membrane oxygenation achieved support of CDH model lambs for up to three weeks. This therapy has the potential to bridge neonates with decompensated respiratory failure to CDH repair with no requirement for systemic anticoagulation, and may be applicable to patients currently precluded from conventional ECMO support.

Umbilical cannulation optimizes circuit flows in premature lambs supported by the EXTra-uterine Environment for Neonatal Development (EXTEND).

KEY POINTS: Bronchopulmonary dysplasia is a disease of extreme prematurity that occurs when the immature lung is exposed to gas ventilation. We designed a novel 'artificial womb' system for supporting extreme premature lambs (called EXTEND) that obviates gas ventilation by providing oxygen via a pumpless arteriovenous circuit with the lamb submerged in sterile artificial amniotic fluid. In the present study, we compare different arteriovenous cannulation strategies on EXTEND, including carotid artery/jugular vein (CA/JV), carotid artery/umbilical vein (CA/UV) and umbilical artery/umbilical vein (UA/UV). Compared to CA/JV and CA/UV cannulation, UA/UV cannulation provided significantly higher, physiological blood flows to the oxygenator, minimized flow interruptions and supported significantly longer circuit runs (up to 4 weeks). Physiological circuit blood flow in UA/UV lambs made possible normal levels of oxygen delivery, which is a critical step toward the clinical application of artificial womb technology. ABSTRACT: EXTEND (EXTra-uterine Environment for Neonatal Development) is a novel system that promotes physiological development by maintaining the premature lamb in a sterile fluid environment and providing gas exchange via a pumpless arteriovenous oxygenator circuit. During the development of EXTEND, different cannulation strategies evolved with the aim of improving circuit flow. The present study examines how different cannulation strategies affect EXTEND circuit haemodynamics in extreme premature lambs. Seventeen premature lambs were cannulated at gestational ages 105-117 days (term 145-150 days) and supported on EXTEND for up to 4 weeks. Experimental groups were distinguished by cannulation strategy: carotid artery outflow and jugular vein inflow (CA/JV; n = 4), carotid artery outflow and umbilical vein inflow (CA/UV; n = 5) and double umbilical artery outflow and umbilical vein inflow (UA/UV; n = 8). Circuit flows and pressures were measured continuously. As we transitioned from CA/JV to CA/UV to UA/UV cannulation, mean duration of circuit run and weight-adjusted circuit flows increased (P < 0.001) and the frequency of flow interruptions declined (P < 0.05). Umbilical vessels generally accommodated larger-bore cannulas, and cannula calibre was directly correlated with circuit pressures and indirectly correlated with flow:pressure ratio (a measure of post-membrane resistance). We conclude that UA/UV cannulation in fetal lambs on EXTEND optimizes circuit flow dynamics and flow stability and also supports circuit flows that closely approximate normal placental flow.

Right Congenital Diaphragmatic Hernias: Is There a Correlation between Prenatal Lung Volume and Postnatal Survival, as in Isolated Left Diaphragmatic Hernias?

OBJECTIVES: Whereas left-sided congenital diaphragmatic hernias (L-CDH) have been extensively studied and their prognostic parameters delineated, right-sided hernias (R-CDH) have not. Published results remain inconclusive. The aim of this study is to evaluate if proven prognostic indicators of postnatal survival in the fetus with L-CDH apply to the fetus with R-CDH. METHODS: Retrospective single-center study of R-CDH fetuses with available prenatal studies assessed for fetal lung volume by means of ultrasound-measured observed versus expected (O/E) lung area to head circumference (LHR) and magnetic resonance-calculated O/E total lung volume (TLV) in a 12-year time period. Percentage of herniated liver volume and postnatal use of extracorporeal membrane oxygenation (ECMO) were also evaluated. RESULTS: In a cohort of 24 patients, O/E LHR, O/E TLV, percentage of herniated liver, and postnatal use of ECMO are not prognostic indicators of survival in the fetus with R-CDH. Cut-off values of O/E LHR of ≤45 or O/E TLV ≤25, known to select a population of severe cases for the L-CDH fetus, do not appear to extrapolate to the R-CDH fetus, as survival in both R-CDH groups is 60%. CONCLUSION: The findings in this study suggest that L- and R-CDH appear to behave differently, and that factors that make L-CDH fatal (low O/E TLV and O/E LHR, high-volume herniated liver) may not apply to the fetus with R-CDH.

Corrigendum: An extra-uterine system to physiologically support the extreme premature lamb.

This corrects the article DOI: 10.1038/ncomms15112.

An EXTrauterine environment for neonatal development: EXTENDING fetal physiology beyond the womb.

Extreme prematurity is a major cause of neonatal mortality and morbidity, and remains an unsolved clinical challenge. The development of an artificial womb, an extrauterine system recreating the intrauterine environment, would support ongoing growth and organ maturation of the extreme preterm fetus and would have the potential to substantially improve survival and reduce morbidity. Previous efforts toward the development of such a system have demonstrated the ability to maintain the isolated fetus for short periods of support, but have failed to achieve the long-term stability required for clinical application. Here we describe our initial experiments demonstrating the stable support of fetal lambs developmentally equivalent to the extreme premature infant for up to four weeks with stable hemodynamics, growth, and development. The achievement of long-term physiologic support of the fetus in an extrauterine system has the potential to fundamentally change the management and clinical outcome of the extreme premature infant.

An extra-uterine system to physiologically support the extreme premature lamb.

In the developed world, extreme prematurity is the leading cause of neonatal mortality and morbidity due to a combination of organ immaturity and iatrogenic injury. Until now, efforts to extend gestation using extracorporeal systems have achieved limited success. Here we report the development of a system that incorporates a pumpless oxygenator circuit connected to the fetus of a lamb via an umbilical cord interface that is maintained within a closed 'amniotic fluid' circuit that closely reproduces the environment of the womb. We show that fetal lambs that are developmentally equivalent to the extreme premature human infant can be physiologically supported in this extra-uterine device for up to 4 weeks. Lambs on support maintain stable haemodynamics, have normal blood gas and oxygenation parameters and maintain patency of the fetal circulation. With appropriate nutritional support, lambs on the system demonstrate normal somatic growth, lung maturation and brain growth and myelination.

Rate of increase of lung-to-head ratio over the course of gestation is predictive of survival in left-sided congenital diaphragmatic hernia.

PURPOSE: Congenital diaphragmatic hernia (CDH) is associated with high postnatal mortality because of pulmonary hypoplasia. The prognostic utility of serial lung-to-head circumference measurements as a marker of lung growth has not been described. Our objective was to examine the relationship between the rate of interval increase of LHR and postnatal survival in left-sided CDH. METHODS: We retrospectively reviewed charts of all left-sided CDH patients from January 2004 to July 2014. All ultrasound studies performed at our institution (n=473) were reviewed. Categorical and continuous data were analyzed by chi-square and Mann-Whitney t-test, respectively, and slope analysis was performed by linear regression analysis (p<0.05). RESULTS: A total of 226 patients were studied, with 154 long-term survivors and 72 non-survivors. Established markers of CDH severity, including intrathoracic liver position and requirement for patch repair, were significantly increased in non-survivors (p<0.0001). The rate of LHR increase as measured by linear regression and slope analysis was significantly increased in long-term survivors (p=0.0175). CONCLUSIONS: Our findings indicate that the interval increase in LHR levels over the course of gestation correlate with survival in left-sided CDH patients. Regular ultrasonographic re-evaluation of LHR throughout gestation following diagnosis of CDH may provide prognostic insight and help guide patient management.

Right- versus left-sided congenital diaphragmatic hernia: a comparative outcomes analysis.

PURPOSE: Right-sided congenital diaphragmatic hernia (R-CDH) occurs in up to 25% of all CDH cases, but has been less widely studied compared to left-sided defects. We sought to compare characteristics and outcomes of left- versus right-sided defects in a large cohort of CDH patients who underwent standardized treatment and follow-up at a single institution. METHODS: We retrospectively reviewed charts of all CDH patients in our pulmonary hypoplasia program from January 2002 through December 2014. Categorical variables were analyzed by Fisher's exact test and continuous variables by Mann-Whitney t-test (p≤0.05). RESULTS: A total of 330 CDH patients were treated more than the 12-year study period, with 274 (83%) left-sided and 56 (17%) right-sided cases identified. Specific pulmonary morbidities were associated with R-CDH, with increased duration of nitric oxide therapy, increased requirement for tracheostomy, increased requirement for supplemental oxygen at the time of NICU discharge, and increased chronic pulmonary hypertension with requirement for long-term Sildenafil therapy. CONCLUSIONS: In this series, R-CDH was not associated with increased mortality, but was associated with increased requirement for pulmonary vasodilatory therapy and requirement for tracheostomy. The high incidence of pulmonary complications indicates increased severity of pulmonary hypoplasia in R-CDH, supporting a role for delivery in tertiary centers with expertise in CDH management.