The role of extracorporeal membrane oxygenation in the management of infants with congenital diaphragmatic hernia

Achieving adequate growth in infants with congenital diaphragmatic hernia prior to discharge

BACKGROUND/PURPOSE

To evaluate the enteral feeding requirements, including caloric provisions, of infants with CDH in relation to growth patterns.

METHODS

A retrospective observational study was conducted on infants with CDH between August 2012 and March 2017. Electronic medical records were reviewed to extract detailed infant feeding data and anthropometric measurements at monthly intervals until discharge. Statistical methods of analysis included generalized linear models, Pearson correlation coefficient, Analysis of variance (ANOVA), Kruskal-Wallis, Wilcoxon rank sum, and Fisher's Exact tests.

RESULTS

Among 149 infants with CDH, 45% (n = 67) met criteria for malnutrition at discharge. Maternal human milk (HM) was initiated in 95% of infants (n = 142) and continued in 79% of infants (n = 118) at discharge. Overall, 50% received fortification of feeds, including 60% (n = 89) of formula fed infants compared to only 21% (n = 31) of HM fed infants (p<0.001). Infants fed formula had lower weight-for-length z-scores at discharge compared to those fed HM.

CONCLUSIONS

Infants receiving HM demonstrated improved growth compared to formula fed infants. However, higher calorie feeding regimens need to be initiated earlier to improve growth velocity. Prompt recognition of malnutrition and growth failure with aggressive supplementation may improve the overall growth of infants with CDH and has the potential to improve long term neurodevelopmental outcomes.

Primary contributors to gastrostomy tube placement in infants with Congenital Diaphragmatic Hernia

OBJECTIVE

To identify factors associated with gastrostomy tube (GT) placement in infants with congenital diaphragmatic hernia (CDH).

METHODS

Retrospective cohort study of 114 surviving infants with CDH at a single tertiary care neonatal intensive care unit from 2010-2019. Prenatal, perinatal and postnatal characteristics were compared between patients who were discharged home with and without a GT. Prenatal imaging was available for 50.9% of the cohort. Logistic regression was used to assess the association between GT placement and pertinent clinical factors. ROC curves were generated, and Youden's J statistic was used to determine optimal predictive cutoffs for continuous variables. Elastic net regularized regression was used to identify variables associated with GT placement in multivariable analysis.

RESULTS

GT was placed in 43.9% of surviving infants with CDH. Prenatal variables predictive of GT placement were percent predicted lung volume (PPLV) <21%, total lung volume (TLV) <30 ml, lung-head ratio (LHR) <1.2 or observed to expected LHR (O/E LHR) <55%. Infants who required a GT were diagnosed earlier prenatally (23.6 ± 3.4 vs. 26.4 ± 5.6 weeks). Patients whose stomach was above the diaphragm on prenatal ultrasound (up) had a higher odds of GT placement compared to those with stomachs below the diaphragm (down) position by a factor of 2.9 (95% CI: 1.25, 7.1); p = 0.0154. Postnatally, infants with GT had lower Apgar scores at 1 and 5 min, longer lengths of stay and higher proportion of flap closures. Infants with a type C or D defect and extracorporeal membrane oxygenation (ECMO) were associated with increased odds of needing a GT. Postnatal association included being NPO for >12 days, need for transpyloric (TP) feeds for >10 days, >14 days to transition to a 30 min bolus feed, presence of gastro-esophageal reflux (GER), chronic lung disease and pulmonary hypertension. In multivariable analysis, duration of NPO, time to TP feeds, transition to 30 min bolus feeds remained significantly associated with GT placement after adjusting for severity of pulmonary hypertension (PH), GER diagnosis and sildenafil treatment.

CONCLUSION

Identification of risk factors associated with need for long-term feeding access may improve timing of GT placement and prevent prolonged hospitalization related to feeding issues.

LEVEL OF EVIDENCE RATING

Level II (Retrospective Study).

Re-ECMO for congenital diaphragmatic hernia: Is it worth the effort?

AIM

To evaluate the results in CDH patients subjected to a second course of ECMO at a single institution.

MATERIAL AND METHODS

Retrospective review of medical charts of patients treated for CDH and ECMO in our center since 1990 to December 2018 was performed. For patients subjected to a second course of ECMO and who survived to hospital discharge charts from follow up visits were also reviewed.

RESULTS AND DISCUSSION

From Jan 1990 until December 2018, 311 patients with CDH were treated in the department. 267 of these (86%) were discharged alive from the hospital and 81% (237/293) of the Swedish patients were alive by December 2018. 101 patients (32%) were subjected to ECMO treatment of whom 71 survived (70%). 22 patients underwent a second ECMO run and 13 of these survived to hospital discharge. Seven of the Swedish patients [19] were long-term survivors (37%). The vast majority was on V-A ECMO.

CONCLUSIONS

It is possible to recannulate the right common carotid artery and internal jugular vein for a second course of venoarterial ECMO in CDH patients, who deteriorate severely after decannulation. Previous research has shown that long-term survivors subjected to ECMO twice reported similar frequencies of pulmonary, gastrointestinal, neurological and musculoskeletal sequelae as the long-term survivors, who needed ECMO support only once, and similar health-related quality of life. Regarding their psychosocial function, they scored within normal range in the behavioral, emotional and social scales domains. A second ECMO run may contribute to a higher survival and that the long-term morbidity among survivors is not more pronounced than among survivors after a single course of ECMO. It is therefore suggested that a second course of ECMO should be offered on the same indications as the first course.

LEVEL OF EVIDENCE

III Case series.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

Level III.

Thoracoscopic Repair of Congenital Diaphragmatic Hernia After Extracorporeal Membrane Oxygenation: Feasibility and Outcomes

INTRODUCTION

Thoracoscopic repair of congenital diaphragmatic hernia (CDH) has been associated with faster recovery, earlier extubation, and decreased morbidity. Nevertheless, thoracoscopic repair is rarely attempted in the post-extracorporeal membrane oxygenation (ECMO) patient. Commonly cited reasons for not attempting thoracoscopy include concerns that the patients' respiratory status is too tenuous to tolerate insufflation pressures or that presumed defect size is so large that it precludes thoracoscopic repair. Our purpose is to review our experience with post-ECMO thoracoscopic CDH repair and evaluate the success of this approach.

METHODS

We performed retrospective analysis of attempted thoracoscopic CDH repairs after ECMO decannulation at our institution from 2001 to 2015. Primary outcome was rate of conversion. Secondary outcomes were intraoperative end-tidal CO₂, time to extubation, and rate of recurrence.

RESULTS

We identified 21 post-ECMO patients in whom thoracoscopic CDH repair was attempted. Thoracoscopic repair was successfully completed in 28%. No patients had reported intolerance to insufflation at 3-7 mmHg. Average end-tidal CO₂ at 15 operative minutes was 36.9 mmHg in the thoracoscopic group versus 50.7 mmHg in the open group and at 60 minutes was 34.25 mmHg versus 45.6 mmHg, respectively. One patient in the thoracoscopic group died and 1 experienced a large pneumothorax. In the converted group there was one clinically significant pneumothorax and three pleural effusions. Survivors after thoracoscopy were extubated an average of 5.6 ± 2.6 days after surgery versus 19.4 ± 10 days in the converted group (P < .05). Recurrence rates at last follow-up were equal between the two groups at 20%.

CONCLUSIONS

Thoracoscopic CDH repair is both safe and feasible after ECMO with no increase in operative morbidity or mortality. Insufflation pressures of 3-7 mmHg are well tolerated without undue increase in end-tidal CO_2. When compared to conversion cases, thoracoscopic repair is associated with significantly decreased time to extubation with no difference in recurrence.

Current Practices in the Management of Congenital Diaphragmatic Hernia Patients Requiring Extracorporeal Membrane Oxygenation: Results of an International Survey of Pediatric Surgeons

INTRODUCTION

There is little consensus on optimal management for congenital diaphragmatic hernia extracorporeal membrane oxygenation (CDH ECMO) patients. Meaningful comparisons of the various approaches have been limited due to the low number of cases in institutions. In addition, the multidisciplinary reliance and rigid institutional framework of ECMO serve to further limit exposure to alternative practices. The goal of this study is to survey the international pediatric surgery community to describe the current practice trends.

METHODS

A survey was electronically distributed to the international pediatric surgical community. The results were evaluated using statistical analysis.

RESULTS

A total of 123 pediatric surgeons completed the survey, of whom 89% work at institutions offering both venoatrial (VA) and venovenous (VV) ECMO. Although 69% perform VA ECMO for CDH, only 46% felt VA was the "optimal method." Among VV proponents, 21% believe the rate of VV to VA conversion to be <5% and 16% believe it to be >30% compared with 0% and 40% in VA proponents. Distribution of timing of repair: 46% post-ECMO repair, 22% early ECMO repair, 15% whenever stabilized on ECMO, and 14% late ECMO repair. Sixty-four percent (71/111) would perform an ECMO CDH repair in the unweanable patient and 27% (30/111) report successful decannulation after repair of a patient who was unweanable on ECMO for 2 weeks. Ninety-two percent do not perform exit-to-ECMO.

CONCLUSION

There are significant practice variations in the management of CDH ECMO. Majority of pediatric surgeons perform VA ECMO in CDH patients; however, a significant percentage of those believe VV to be more optimal. This discrepancy is not accounted for by the VA-only institutions. Although post-ECMO CDH repair is the most common approach, the majority would perform a repair "on ECMO" if the patient was unweanable. In addition, although many pediatric surgeons believe the "last ditch repair" for the unweanable patient to be futile, 27% have reported success. Exit-to-ECMO for CDH remains a minority practice.

Improved mortality rate for congenital diaphragmatic hernia in the modern era of management: 15 year experience in a single institution

BACKGROUND/PURPOSE

Mortality rates with congenital diaphragmatic hernia (CDH) have remained at approximately 30% for the last 2 decades. Therapies targeting pulmonary hypertension (PHTN) have not been systematically studied in this population, but are increasingly used. We hypothesized that incremental changes in treatments for PHTN have improved mortality for CDH infants.

METHODS

Prospective data from 1998 to 2013 on all liveborn CDH patients treated at our institution were retrospectively analyzed. Based on management of PHTN, 4 eras were identified for comparison. Logistic and linear regression were used to compare characteristics. The primary outcome of death prior to discharge was analyzed by multivariable Cox regression modeling.

RESULTS

The study included 192 infants who met inclusion criteria. Length of stay increased, whereas rates of primary repair decreased, suggesting a sicker cohort in the most recent eras. Analysis of mortality across 4 eras showed no difference. By post-hoc analysis, ECMO availability was associated with mortality reduction for eras 3-4 versus 1-2 (HR=0.27, p<0.001).

CONCLUSIONS

Improved survival at our institution may be related to recent introduction of ECMO and more aggressive approaches to pulmonary hypertension. Further systematic studies of these PHTN therapies in this specific population are warranted.

Repair of congenital diaphragmatic hernias on Extracorporeal Membrane Oxygenation (ECMO): does early repair improve patient survival?

INTRODUCTION

The optimal timing of repair for congenital diaphragmatic hernia (CDH) patients that require ECMO is controversial. Early repair on ECMO theoretically allows for restoration of normal thoracic anatomy but entails significant bleeding risks. The purpose of this study was to examine the institutional outcomes of early CDH repair on ECMO.

METHODS

The records of infants with CDH placed on ECMO from 2001 to 2011 were reviewed. Since 2009, a protocol was instituted for early repair while on ECMO. For this study, three cohorts were analyzed: early repair (<72 h), late repair (>72 h), and post-decannulation. These groups were compared for outcomes regarding morbidity and survival.

RESULTS

Forty-six CDH patients received ECMO support with an overall survival of 53%. Twenty-nine patients (11 early/18 late) were repaired on ECMO, while 17 patients had repair post-decannulation. Survival was 73%, 50%, and 64% for those repaired early, late, or post-decannulation, respectively. Despite significantly worse prenatal factors, patients repaired early on ECMO had a similar survival. When comparing patients repaired on ECMO, the early group patients were decannulated 6 days earlier (p-value=0.009) and had significantly lower circuit complications (p=0.03).

CONCLUSION

In conclusion, early repair on ECMO was associated with decreased ECMO duration, decreased circuit complications, and a trend towards improved survival.

The impact of ethnic population dynamics on neonatal ECMO outcomes: a single urban institutional study

INTRODUCTION

Neonatal extracorporeal membrane oxygenation ECMO has been clinically used for the last 25 y. It has been an effective tool for both cardiac and non cardiac conditions. The impact of ethno-demographic changes on ECMO outcomes however remains unknown. We evaluated a single institution's experience with non cardiac neonatal ECMO over a 28-y period.

METHODS

A retrospective review of all neonates undergoing noncardiac ECMO between the y 1984 and 2011 was conducted and stratified into year groups I, II, III (≤1990, 1991-2000, and ≥2001). Demographic, clinical, and outcome data were collected. The patient specifics, ECMO type, ECMO length, blood use, complications, and outcomes were analyzed. Univariate, bivariate, and multivariate analyses were then performed.

RESULTS

Data was available for 827 patients. The number of African-American and Hispanic patients increased over the last 27 y (27.5% versus 45.0% and 3.3% versus 21.5%, year group I versus year group III, respectively). The proportion of congenital diaphragmatic hernia (CDH) patients by ethnicity also increased for African-Americans and Hispanics between the two year groups (22.0% to 33.0% and 4.9% to 33.0%, respectively). Similar pattern was noted for non-CDH diagnoses. Low birth weight, low APGAR scores, CDH, primary pulmonary hypertension, central nervous system hemorrhage, and ECMO were independent predictors of mortality. Ethnicity, in itself however, was not associated with mortality on adjusted analysis.

CONCLUSION

More African-Americans and Hispanics have required ECMO over the years with a concurrent decrease in the number of Caucasians. While ethnicity was not an independent predictor of mortality, it appears to be a surrogate for fatal but sometime preventable diagnoses among minorities. Further investigations are needed to better delineate the reason behind this disparity.

Postoperative regional distribution of pulmonary ventilation and perfusion in infants with congenital diaphragmatic hernia

BACKGROUND/PURPOSE

Advances in management of patients with congenital diaphragmatic hernia (CDH) have improved mortality rates but with a risk of increased pulmonary morbidity. The prognosis for CDH survivors remains difficult to predict owing to the lack of adequate methods. We used single photon emission computed tomography (SPECT) to measure the regional distribution of ventilation and perfusion in CDH infants to quantify the degree of lung function impairment and relate it to neonatal clinical disease severity.

METHODS

Single photon emission computed tomography was performed in 12 CDH infants at the mean age of six months. Ventilation and perfusion were traced with 5 MBq Technegas and technetium-labelled albumin macro-aggregates, respectively. Neonatal clinical data collected during the patient's stay in the pediatric intensive care unit was correlated with the SPECT data.

RESULTS

Single photon emission computed tomography revealed varying degrees of ventilation-perfusion abnormalities which correlated with the presence of pulmonary artery hypertension, days on ventilator and days on extracorporeal membrane oxygenation.

CONCLUSIONS

The grade of clinical disease severity in infants following CDH repair is closely related to the ventilation-perfusion abnormality as seen using SPECT. The persistence of pulmonary artery hypertension into the postoperative neonatal period appears to be an important pathophysiological factor related to ventilation-perfusion abnormalities. Single photon emission computed tomography provides valuable clinical information for patient follow-up.

Patch repair is an independent predictor of morbidity and mortality in congenital diaphragmatic hernia

BACKGROUND

Infants with congenital diaphragmatic hernia (CDH) have variable outcomes. There is a considerable potential benefit in being able to predict perinatally, which infants have severe hypoplasia and are thus more likely to die or survive with significant morbidity. We examine the relationship between a need for patch repair of CDH (PR) and outcome, using a national database.

METHODS

Baseline characteristics of patients undergoing PR or non-patch repair (NPR) were compared. Multivariate analysis was performed to determine the association of PR with mortality and morbidity independent of other known predictors.

RESULTS

Baseline characteristics of PR and NPR infants were similar although those infants with PR had higher SNAP-II scores. PR was an independent predictor of mortality with an odds ratio of 17.1 (95%CI 2.0-149.2) and was independently associated with secondary outcome measures of morbidity, including the need for oxygen at discharge and the duration of ventilation.

CONCLUSIONS

Infants requiring PR have significantly higher mortality and suffer greater morbidity than those undergoing NPR. This association is independent of other known predictors of mortality. Identifying prenatal features associated with this high risk group would be of great clinical value.

Costs of congenital diaphragmatic hernia repair in the United States-extracorporeal membrane oxygenation foots the bill

BACKGROUND

Congenital diaphragmatic hernia (CDH) is the costliest noncardiac congenital defect. Extracorporeal membrane oxygenation (ECMO) is a treatment strategy offered to those babies with CDH who would not otherwise survive on conventional therapy. The primary objective of our study was to identify the leading source of expenditures in CDH care.

METHODS

All patients surviving CDH repair were identified in the Kids' Inpatient Database (KID) from 1997 to 2006, with costs converted to 2006 US dollars. Patients were categorized into groups based on severity of disease for comparison including CDH repair only, prolonged ventilator dependence, and ECMO use. Factors associated with greater expenditures in CDH management were analyzed using a regression model.

RESULTS

Eight hundred thirty-nine patients from 213 hospitals were studied. Extracorporeal membrane oxygenation use decreased from 18.2% in 1997 to 11.4% in 2006 (P = .002). Congenital diaphragmatic hernia survivors managed with ECMO cost more than 2.4 times as much as CDH survivors requiring only prolonged ventilation postrepair and 3.5 times as much as those with CDH repair only (both P < .001). Age, multiplicity of diagnoses, patient transfer, inhaled nitric oxide use, prolonged ventilation, and ECMO use were all associated with higher costs. Extracorporeal membrane oxygenation use was the single most important factor associated with higher costs, increasing expenditures 2.4-fold (95% confidence interval, 2.1-2.8). Though the CDH repair with ECMO group constituted 12.2% of patients, this group has the highest median costs ($156,499.90/patient) and constitutes 28.5% of national costs based on CDH survivors in the KID. Annual national cost for CDH survivors is $158 million based on the KID, and projected burden for all CDH patients exceeds $250 million/year.

CONCLUSIONS

Extracorporeal membrane oxygenation use is the largest contributing factor to the economic burden in CDH. With limited health care resources, judicious resource utilization in CDH care merits further study.

Improvement of survival in infants with congenital diaphragmatic hernia in recent years: effect of ECMO availability and associated factors

BACKGROUND/PURPOSE

Survival of patients with congenital diaphragmatic hernia (CDH) depends both on non-modifiable congenital conditions and on modifiable pre and postnatal management. ECMO improves survival up to 80% in neonates with CDH in the best ECMO centers worldwide. The first Neonatal ECMO Program in Chile was started in our University in 2003. Our objective is to determine the impact of a Neonatal ECMO Program in a level III NICU on newborns with CDH.

METHODS

Data of all newborns with CDH admitted to our NICU was separated into two groups: pre ECMO (1996-2003) and ECMO (2003-2007). Crude and adjusted odds ratios for 24 months survival were estimated by logistic regression.

RESULTS

Data of 46 newborns with CDH was analysed, 20 in the pre ECMO and 26 in the ECMO period. Patient characteristics were similar in both groups; however, 24-month survival increased significantly from 25% (5/20) in the pre ECMO period to 77% (20/26) in the ECMO period (P = 0.001). Adjusted odds ratios for 24-month survival were 26.98 for OI <or= 40, 7.58 for 5 min Apgar >or= 7 and 17.5 for ECMO availability.

CONCLUSIONS

The establishment of an ECMO program was associated with a significant increase in long-term survival for infants with CDH.

Recent advances in the management of congenital diaphragmatic hernia

The management of congenital diaphragmatic hernia (CDH) is undergoing continual change and refinement, fuelled by recent advances in this field. Although many studies have documented the benefits of these recent advances but definite recommendations are lacking. Also, injudicious use of some of these strategies may be counterproductive, underscoring the importance of evidence based treatment strategy. This article discusses the utility of the recent advances in the management of CDH.

Outcome analysis of neonates with congenital diaphragmatic hernia treated with venovenous vs venoarterial extracorporeal membrane oxygenation

PURPOSE

Venoarterial extracorporeal membrane oxygenation (ECMO) (VA) is used more commonly in neonates with congenital diaphragmatic hernia (CDH) than venovenous ECMO (VV). We hypothesized that VV may result in comparable outcomes in infants with CDH requiring ECMO.

METHODS

We retrospectively analyzed the Extracorporeal Life Support Organization (ELSO) database (1991-2006). Multivariate logistic regression analyses were used to compare VV- and VA-associated mortality.

RESULTS

Four thousand one hundred fifteen neonates required ECMO, with an overall mortality rate of 49.6%. Venoarterial ECMO was used in 82% and VV in 18% of neonates. Pre-ECMO inotrope use and complications were equivalent between VA and VV. The mortality rate for VA and VV was 50% and 46%, respectively. After adjusting for birth weight, gestational age, prenatal diagnosis, ethnicity, Apgar scores, pH less than 7.20, Paco(2) greater than 50, requiring high-frequency ventilation, and year of ECMO, there was no difference in mortality between VV vs VA. Renal complications and on-ECMO inotrope use were more common with VV, whereas neurologic complications were more common with VA. The conversion rate from VV to VA was 18%; conversion was associated with a 56% mortality rate.

CONCLUSION

The short-term outcomes of VV and VA are comparable. Patients with CDH who fail VV may be predisposed to a worse outcome. Nevertheless, VV offers equal benefit to patients with CDH requiring ECMO while preserving the native carotid.

Congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation: does timing of repair matter?

PURPOSE

Severe congenital diaphragmatic hernia (CDH) requiring extracorporeal membrane oxygenation (ECMO) is associated with high mortality. Timing of CDH repair relative to ECMO therapy remains controversial. Our hypothesis was that survival would significantly differ between those who underwent repair during ECMO and those who underwent repair after ECMO therapy.

METHODS

We examined deidentified data from the CDH study group (CDHSG) registry from 1995 to 2005 on patients who underwent repair and ECMO therapy (n = 636). We used Cox regression analysis to assess differences in survival between those who underwent repair during and after ECMO.

RESULTS

Five covariates were significantly associated with mortality as follows: timing of repair relative to ECMO (P = .03), defect side (P = .01), ECMO run length (P < .01), need for patch repair (P = .03), birth weight (P < .01), and Apgar score at 5 minutes (P = .03). Birth year, inborn vs transfer status, diaphragmatic agenesis, age at repair, and presence of cardiac or chromosomal abnormalities were not associated with survival. Repair after ECMO therapy was associated with increased survival relative to repair on ECMO (hazard ratio, 1.407; P = .03).

CONCLUSION

These data suggest that CDH repair after ECMO therapy is associated with improved survival compared to repair on ECMO, despite controlling for factors associated with the severity of CDH.

Changing perspectives on the perinatal management of isolated congenital diaphragmatic hernia in Europe

Congenital diaphragmatic hernia (CDH) should be diagnosed in the prenatal period and prompt referral to a tertiary referral center for imaging, genetic testing, and multidisciplinary counseling. Individual prediction of prognosis is based on the absence of additional anomalies, lung size, and liver herniation. In severe cases, a prenatal endotracheal balloon procedure is currently being offered at specialized centers. Fetal intervention is now also offered to milder cases within a trial, hypothesizing that this may reduce the occurrence of bronchopulmonary dysplasia in survivors. Postnatal management has been standardized by European high-volume centers for the purpose of this and other trials.

Right-sided congenital diaphragmatic hernia: high utilization of extracorporeal membrane oxygenation and high survival

PURPOSE

The purpose of the study was to assess the treatment strategies and outcome of right-sided congenital diaphragmatic hernia (R-CDH), particularly extracorporeal membrane oxygenation (ECMO).

METHODS

We reviewed the cases of 42 patients treated for R-CDH at our institution from 1991 to 2006. We gathered demographic information, documented ECMO use and the type of surgical repair, and compared outcomes with predicted survival as calculated by the CDH Study Group's equation.

RESULTS

Of the 35 patients included in our statistical analysis (7 were excluded), 12 (34%) were born at our institution, all of whom were prenatally diagnosed with R-CDH. Nineteen patients (54%) required ECMO therapy. Extracorporeal membrane oxygenation was initiated after repair of the R-CDH in 2 patients (11%). Of those patients who went on ECMO before repair, 4 patients (21%) were repaired on ECMO, 9 patients (47%) underwent repair after ECMO, and 4 patients (21%) underwent ECMO but died before their R-CDH could be repaired. Primary repair of the diaphragm was possible in 15 cases (56%), and primary closure of the abdominal incision was possible in 15 of the 23 open repairs (65%). The mean predicted survival for all 35 patients was 63%, whereas 28 (80%) actually survived. Logistic regression showed a significant association between the presence of cardiac defects and mortality (odds ratio = 0.008, P = .014).

CONCLUSIONS

Our data suggest that patients with R-CDH have high ECMO utilization and may experience greater relative benefit from ECMO as evidenced by their higher-than-expected overall survival. Extracorporeal membrane oxygenation may be found to have a distinctive role in managing R-CDH. More high-powered series are needed to elucidate differences between R-CDH and left-sided CDH that may dictate alternate forms of management.

Identifying neonates at a very high risk for mortality among children with congenital diaphragmatic hernia managed with extracorporeal membrane oxygenation

PURPOSE

The purpose of this study was to identify mortality risk factors in children with congenital diaphragmatic hernia (CDH) treated with extracorporeal membrane oxygenation (ECMO) and generate a prediction score for those at a very high risk for mortality.

METHODS

Data on first ECMO runs of all neonates with CDH, between January 1997 and June 2007, were obtained from the Extracorporeal Life Support Organization registry (N = 2678). The data were split into "training data (TD)" (n = 2006) and "validation data" (n = 672). The primary outcome analyzed was in-hospital mortality. Modified Poisson regression was used for analyses.

RESULTS

Overall in-hospital mortality among 2678 neonates (males, 57%; median age at ECMO, 1 day) was 52%. The univariate and multivariable analyses were performed using TD. An empirically weighted mortality prediction score was generated with possible scores ranging from 0 to 35 points. Of 69 who scored 14 or higher in the TD, 62 died (positive predictive value [PPV], 90%), of 37 with 15 or higher, 35 died (PPV, 95%), of 23 with 16 or higher, 22 died (PPV, 96%). A cut-off point of 15 was chosen and was tested using the separate validation dataset. In validation data, the cut-off point 15 had a PPV of 96% (23 died of 24).

CONCLUSION

Scoring 15 or higher on the prediction score identifies neonates with CDH at a very high risk for mortality among those managed with ECMO and could be used in surgical decision making and counseling.

Prenatal diagnosis, prediction of outcome and in utero therapy of isolated congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) can be associated with genetic or structural anomalies with poor prognosis. In isolated cases, survival is dependent on the degree of lung hypoplasia and liver position. Cases should be referred in utero to tertiary care centers familiar with this condition both for prediction of outcome as well as timed delivery. The best validated prognostic indicator is the lung area to head circumference ratio. Ultrasound is used to measure the lung area of the index case, which is then expressed as a proportion of what is expected normally (observed/expected LHR). When O/E LHR is < 25% survival chances are < 15%. Prenatal intervention, aiming to stimulate lung growth, can be achieved by temporary fetal endoscopic tracheal occlusion (FETO). A balloon is percutaneously inserted into the trachea at 26-28 weeks, and reversal of occlusion is planned at 34 weeks. Growing experience has demonstrated the feasibility and safety of the technique with a survival rate of about 50%. The lung response to, and outcome after FETO, is dependent on pre-existing lung size as well gestational age at birth. Early data show that FETO does not increase morbidity in survivors, when compared to historical controls. Several trials are currently under design.

The impact of strict infection control on survival rate of prenatally diagnosed isolated congenital diaphragmatic hernia

BACKGROUND/PURPOSE

Although the prognosis of congenital diaphragmatic hernia (CDH) is determined by the degree of pulmonary hypoplasia, there may be an occult contribution of infection to outcomes. The purpose of this study is to evaluate the effects of our new supportive therapy to prevent infectious complications on mortality and morbidity of CDH.

METHODS

Among 57 cases with CDH treated between 2002 and 2007, 43 prenatally diagnosed isolated cases were enrolled in this study. All patients were managed by a lung-protective strategy and delayed surgery. Since January 2006, we have optimized our perioperative care to reduce infectious complications by using peripherally inserted central catheters and restriction of invasive procedures including extracorporeal membranous oxygenation (ECMO). The survival rate, intubation period, maximum serum C-reactive protein (CRP) level, and complications were compared before and after the introduction of refined supportive therapy.

RESULTS

There were 25 cases (12 liver-up, 13 liver-down) treated before 2006 and 18 cases (8 liver-up, 10 liver-down) after 2006. ECMO was required for stabilization in five cases before 2006. The survival rates of total, liver-up, and liver-down cases improved from 60, 42, 77, to 83, 63, 100% after 2006, respectively. The intubation period was shortened from 37.8 +/- 24.3 to 22.2 +/- 10.8 days, and the maximum serum CRP level declined from 12.8 +/- 11.5 to 2.2 +/- 1.6 mg/dl after 2006. Nine cases developed sepsis before 2006 whereas no patients suffered from sepsis or pneumonia after 2006.

CONCLUSION

The new supportive therapy with strict infection control improved survival rate of prenatally diagnosed CDH without using ECMO.

NKCC-1 and ENaC are down-regulated in nitrofen-induced hypoplastic lungs with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is accompanied by pulmonary hypoplasia and pulmonary hypertension. Fetal lung growth is dependent on the secretion of lung liquid, which normally is absorbed at partus. The ion channel NKCC-1 is involved in this secretory process, but has recently also been reported to be implicated in absorption. CDH patients show a disturbed transition from secretion to absorption. alpha- and beta-ENaC are essential for lung liquid absorption. Common for all transcellular ion transport is the need for Na/K-ATPase as a primary driving force. The aim of the study was first to map the normal pulmonary expression of the above proteins during late gestation and secondly to see if the expression was affected in a CDH rat model. Pregnant Sprague-Dawley rat dams were given nitrofen on gestational day 9.5 to induce CDH. The fetuses were removed on gestational days E18 and E21. In addition, newborn rats were harvested postpartum on day P2. The fetuses were put into one of two groups: hypoplastic lungs without CDH (N-CDH) and hypoplastic lungs with CDH (N+CDH). The pulmonary expression of NKCC-1, alpha-/beta-ENaC and Na/K-ATPase was then analyzed using Western blot. We found that the protein levels of NKCC-1 on gestational days E18 and E21 were significantly lower among fetuses with N+CDH as well as N-CDH compared to controls. The expression of beta-ENaC was also significantly down-regulated in both the groups on E18 and E21. The protein levels of alpha-ENaC and Na/K-ATPase were not found to be significantly decreased, but both showed a tendency towards down-regulation. The marked down-regulation of NKCC-1 in fetal hypoplastic lungs with CDH indicates a possibly decreased lung liquid production. This may be one of the mechanisms behind the disturbed pulmonary development in CDH. We also show that beta-ENaC is down-regulated. Down-regulation of beta-ENaC may result in abnormal lung liquid absorption, which could be one of the mechanisms behind the respiratory distress seen in CDH patients postpartum.

Redefining outcomes in right congenital diaphragmatic hernia

PURPOSE

Available data comparing the management and outcome of right-sided (R-CDH) vs left-sided congenital diaphragmatic hernia (L-CDH) are inconsistent. Large-volume CDH studies are limited by small numbers of R-CDH or are confounded by compilations from multiple institutions with multiple treatment strategies. Consequently, they are underpowered to draw conclusions. To define the behavior and outcomes of R-CDH better, we report the largest single-institution series of R-CDH and ask if factors traditionally linked to poor prognosis in L-CDH were applicable to R-CDH.

METHODS

We reviewed a single institution's experience with 267 consecutive evaluable neonates with unilateral CDH repaired from 1990 to 2006, with specific focus on R-CDH. chi(2) tests were performed for disease-related categorical variables. Two-tailed unpaired t tests were used for continuous variables. Factors associated with morbidity and survival were determined by univariate regression. Statistical significance was set at P < .05.

RESULTS

Forty right-sided (15%) and 227 (85%) left-sided cases of CDH were identified. Prenatal diagnosis was made in 20 right-sided vs 170 left-sided defects (50% vs 75%, P < .01). Survival was 22 of 40 in R-CDH compared with 175 of 227 in L-CDH (55% vs 77%, P < .01). Extracorporeal membrane oxygenation was required in 16 right-sided and 33 left-sided cases (40% vs 15%, P < .001). A diaphragmatic patch was used in 22 of 29 right-sided compared with 82 of 199 left-sided repairs (76% vs 41%, P < .01); rates of abdominal wall prosthesis were also higher in right-sided hernias (38% vs 19%, P < .05). No differences were detected in right-sided vs left-sided recurrences (14% vs 8%, P = .38), mean time from birth to operation (5.3 vs 4.8 days, P = .80), or presence of cardiac anomalies (15% vs 12%, P = .63). Morbidity persisting beyond 6 months of age was present in 16 of 22 R-CDH survivors compared with 76 of 175 L-CDH survivors (73% vs 43%, P > .05). Among R-CDHs, prenatal diagnosis was the only factor to predict survival by univariate regression (P < .01). Use of a prosthesis in the diaphragm (P < .05) for R-CDH repair correlated with morbidity.

CONCLUSION

Although previous reports suggest that associated anomalies, need for extracorporeal membrane oxygenation, and time to repair can influence L-CDH survival, these data do not support extrapolation to R-CDH survival. Right-sided CDH carries a disproportionately high morbidity and mortality. Prenatal diagnosis was the only factor predictive of R-CDH survival. Morbidity may correlate with use of prosthetic material for R-CDH repair. Right-sided CDH is a unique disease that may require a modified antenatal consultation.

Respiratory failure and extracorporeal membrane oxygenation

Conventional treatment of respiratory failure involves positive pressure ventilation with high concentrations of inspired oxygen. If adequate gas exchange still cannot be achieved extracorporeal membrane oxygenation (ECMO) may be an option. The general indication for ECMO for respiratory insufficiency is a reversible pulmonary disease, which cannot be managed by conventional means. ECMO is a modified heart-lung machine. Blood is withdrawn from a central vein in the patient and pumped through an artificial oxygenator back to the patient, either to a central artery (veno-arterial ECMO) or to a central vein (veno-venous ECMO). Total gas exchange can be achieved through the extracorporeal system, and the lungs do not have to be subjected to high-pressure ventilation. To date over 21,500 neonates have been treated with ECMO with an overall survival to hospital discharge of 76%. Meconium aspiration syndrome carries the highest survival (94%), whereas congenital diaphragmatic hernia on ECMO only has a survival of 52%. A total of 3500 pediatric patients (30 days to 18 years) have been treated with ECMO with a survival of 56%. Aspiration and viral pneumonia are the pediatric diagnoses with the highest survival rates. Randomized controlled studies have shown a significant advantage of ECMO with regard to survival in neonates. In the pediatric age group, nonrandomized studies have shown lower mortality in ECMO-treated patients.

Congenital diaphragmatic hernia

The incidence of congenital diaphragmatic hernia (CDH) may be as high as 1 in 2000. Over the past two decades, antenatal diagnosis rates have increased, the pathophysiology of CDH has become better understood, and advances in clinical care, including foetal surgery, have occurred. However, there remains a paucity of randomised controlled trials to provide evidence-based management guidelines. Reports of improved survival rates appear to be confined to a select subset of CDH infants, surviving to surgical repair, while the overall mortality, at over 60%, appears to be unchanged, largely due to the often forgotten 'hidden mortality' of CDH. The significant long-term morbidity in surviving infants has become apparent, and the need for long-term multidisciplinary follow up established. A total of 10% of cases may present later in life, and misdiagnosis on initial chest X-ray may lead to significant morbidity.

Predictors of outcome in patients with congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation

BACKGROUND

The role of extracorporeal membrane oxygenation (ECMO) in patients with congenital diaphragmatic hernia is still evolving. The use of ECMO is invasive with potential complications during instrumentation for cannulation and heparinization. There are no reliable predictors of outcome in patients requiring ECMO. We aimed to identify (a) the factors that could predict outcome and (b) the incidence and relation of complications during ECMO to outcome.

METHODS

"Pre" ECMO (age, sex, birth weight, blood gasses, and ventilator settings) and "on" ECMO variables (mode of ECMO, use of nitric oxide, surfactant, liquid ventilation, inotropes, timing of repair, and complications on ECMO) were analyzed to identify predictors of outcome.

RESULTS

Fifty-two patients were included. The overall survival was 58%. Mean duration of ECMO (181 +/- 120 vs 317 +/- 156 hours, P = .001), use of nitric oxide (6 vs 10, P = .049), and renal complications (4 vs 14; P < .001) differed between survivors and nonsurvivors. The survival of patients requiring ECMO support for more than 2 weeks is significantly lower than that of patients requiring ECMO support for less than 2 weeks (18% vs 68%, P = .005). Multiple logistic regression revealed ECMO duration of 2 weeks or more and renal complications to be associated with mortality.

CONCLUSION

No pre-ECMO variable could be identified as predictor of mortality. Prolonged duration of ECMO and renal complications on ECMO were independently associated with mortality.

The split abdominal wall muscle flap repair for large congenital diaphragmatic hernias on extracorporeal membrane oxygenation

BACKGROUND

Numerous techniques exist for repairing large congenital diaphragmatic hernias (CDHs) including prosthetic patches, tissue-engineered grafts, and various muscle flaps. A split abdominal wall muscle flap is a simple, durable way to repair a large diaphragmatic hernia. This technique has not gained widespread use, and some have suggested that it would be inappropriate in the setting of extracorporeal membrane oxygenation (ECMO) because of bleeding risk. We present our series of diaphragmatic hernias with a focus on those repaired with the split abdominal wall technique while on ECMO.

METHODS

A retrospective, single-institution chart review was performed on all patients who underwent surgical repair for CDH over 6 years beginning in August 2000.

RESULTS

Seventy-five patients underwent repair. Sixteen were performed with patients on ECMO. Of these, 4 were closed primarily, 7 used a prosthetic patch, and 5 used a split abdominal wall muscle flap. Two patients in the prosthetic group developed a recurrent hernia, and 2 required reoperation for bleeding while on ECMO. No reoperations for bleeding were required in the abdominal muscle flap group.

CONCLUSIONS

The split abdominal wall muscle flap can be safely performed on anticoagulated patients. We believe it is a practical option for repairing large CDHs.

Ex utero intrapartum treatment with extracorporeal membrane oxygenation for severe congenital diaphragmatic hernia

PURPOSE

The purpose of this study was to determine whether ex utero intrapartum treatment with extracorporeal membrane oxygenation (EXIT to ECMO) is a reasonable approach for managing patients antenatally diagnosed with severe congenital diaphragmatic hernia (CDH).

METHODS

A 6-year retrospective review was performed on fetuses with severe CDH (liver herniation and a lung/head ratio <1.4, percentage of predicted lung volume <15, and/or congenital heart disease). Fourteen of the patients underwent EXIT with a trial of ventilation. Fetuses with poor preductal oxygen saturations despite mechanical ventilation received ECMO before their delivery. Maternal-fetal outcomes were analyzed.

RESULTS

There were no maternal-reported complications. Three babies passed the ventilation trial and survived, but 2 of them required ECMO within 48 hours. The remaining 11 fetuses received ECMO before their delivery. Overall survival after EXIT-to-ECMO was 64%. At 1-year follow-up, all survivors had weaned off supplemental oxygen, but 57% required diuretics and/or bronchodilators.

CONCLUSION

This is the largest reported experience using EXIT to ECMO in the management of severe CDH. The EXIT-to-ECMO procedure is associated with favorable survival rates and acceptable pulmonary morbidity in fetuses expected to have a poor prognosis under conventional management.

Treatment evolution in high-risk congenital diaphragmatic hernia: ten years' experience with diaphragmatic agenesis

OBJECTIVE

The objective of this study was to evaluate the impact of newer therapies on the highest risk patients with congenital diaphragmatic hernia (CDH), those with agenesis of the diaphragm.

SUMMARY BACKGROUND DATA

CDH remains a significant cause of neonatal mortality. Many novel therapeutic interventions have been used in these infants. Those children with large defects or agenesis of the diaphragm have the highest mortality and morbidity.

METHODS

Twenty centers from 5 countries collected data prospectively on all liveborn infants with CDH over a 10-year period. The treatment and outcomes in these patients were examined. Patients were followed until death or hospital discharge.

RESULTS

A total of 1,569 patients with CDH were seen between January 1995 and December 2004 in 20 centers. A total of 218 patients (14%) had diaphragmatic agenesis and underwent repair. The overall survival for all patients was 68%, while survival was 54% in patients with agenesis. When patients with diaphragmatic agenesis from the first 2 years were compared with similar patients from the last 2 years, there was significantly less use of ECMO (75% vs. 52%) and an increased use of inhaled nitric oxide (iNO) (30% vs. 80%). There was a trend toward improved survival in patients with agenesis from 47% in the first 2 years to 59% in the last 2 years. The survivors with diaphragmatic agenesis had prolonged hospital stays compared with patients without agenesis (median, 68 vs. 30 days). For the last 2 years of the study, 36% of the patients with agenesis were discharged on tube feedings and 22% on oxygen therapy.

CONCLUSIONS

There has been a change in the management of infants with CDH with less frequent use of ECMO and a greater use of iNO in high-risk patients with a potential improvement in survival. However, the mortality, hospital length of stay, and morbidity in agenesis patients remain significant.

Prenatal intervention for isolated congenital diaphragmatic hernia

PURPOSE OF REVIEW

We aim to review the recent literature regarding early prenatal prediction of outcome in babies diagnosed with isolated congenital diaphragmatic hernia, as well as results of fetal therapy for this condition.

RECENT FINDINGS

Current survival rates in population-based studies are around 55-70%. Highly specialized centers report 80% and more, but discount the hidden mortality, mainly in the antenatal period. Fetuses presenting with liver herniation and a lung-to-head ratio of less than 1.0 measured in midgestation have a poor prognosis. Other volumetric techniques are being evaluated for use in midtrimester. Recently, a randomized trial failed to show benefit from prenatal therapy, but lacked power to document the potential advantage of prenatal therapy in severe cases. We proposed percutaneous fetal endoluminal tracheal occlusion with a balloon at 26-28 weeks through a 3.3 mm incision. In severe cases, fetal endoluminal tracheal occlusion increased lung size as well as survival, with an early (7 day) survival, late neonatal (28 day) survival and survival at discharge of 75, 58 and 50%, respectively, comparing favorably with 9% in contemporary controls. Airways can be restored prior to birth improving neonatal survival (83.3% compared with 33.3%). The procedure carries a risk for preterm prelabour rupture of the fetal membranes, although that may decrease with experience.

SUMMARY

Fetuses with severe congenital diaphragmatic hernia can be identified in the second trimester. Fetal endoluminal tracheal occlusion can be considered as a minimally invasive fetal therapy, improving outcome in such highly selected cases.