A prospective randomized trial of delayed versus immediate repair of congenital diaphragmatic hernia

Surgical approaches to congenital diaphragmatic hernia

Surgical repair of the diaphragm is essential for survival in congenital diaphragmatic hernia (CDH). There are many considerations surrounding the operation - why the operation matters, optimal timing of repair and its relation to extracorporeal life support (ECLS) use, minimally invasive versus open approaches, and strategies for reconstruction. Surgery is both affected by, and affects, the physiology of these infants and is an important factor in determining long-term outcomes. Here we discuss the evidence and provide insight surrounding this complex decision making, technical pearls, and outcomes in repair of CDH.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Operative repair in congenital diaphragmatic hernia: How long do we really need to wait?

OBJECTIVE

To analyze preoperative cardiopulmonary support and define preoperative stability relative to timing of surgical repair for CDH neonates not on ECMO.

STUDY DESIGN

We retrospectively analyzed repeated measures of oxygenation index (OI; Paw*FiO₂×100/PaO₂) among 158 neonates for temporal preoperative trends. We defined physiologic stability using OI and characterized ventilator days and discharge age relative to delay in repair beyond physiologic stability.

RESULTS

The OI in the first 24 h of life was temporally reliable and representative of the preoperative mean (ICC 0.70, 95% CI 0.61-0.77). A pre-operative OI of ≤ 9.4 (AUC 0.95) was predictive of survival. Surgical delay after an OI ≤ 9.4 resulted in increased ventilator days (1.4, 95% CI 1.1-1.9) and discharge age (1.5, 95% CI 1.2-2.0). When prospectively applied to a subsequent cohort, an OI ≤ 9.4 was again reflective of physiologic stability prior to repair.

CONCLUSION

OI values are temporally reliable and change minimally after 24 h age. Delay in surgical repair of CDH beyond initial stability increases ventilator days and discharge age without a survival benefit.

LEVEL OF EVIDENCE

Prognosis study, Level III.

Diagnosis & management of pulmonary hypertension in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) contributes to neonatal morbidity and mortality worldwide. Pulmonary hypertension (PH) is a key component of CDH pathophysiology and critical consideration for management and therapeutic options. PH associated with CDH has traditionally been attributed to pulmonary vascular maldevelopment and associated lung parenchymal hypoplasia, leading to pre-capillary increase in pulmonary vascular resistance (PVR). However, there is increasing recognition that left ventricular hypoplasia, dysfunction and elevated end diastolic pressure may contribute to post-capillary pulmonary hypertension in CDH patients. The interplay of these mechanisms and associated dysfunction in the right and left ventricles results in variable hemodynamic phenotypes in CDH. Clinical assessment of individual phenotype may help guide personalized management strategies, including effective use of pulmonary vasodilators and extra-corporeal membrane oxygenation. Ongoing investigation of the underlying mechanisms of PH in CDH, and efficacy of physiology-based treatment approaches may support improvement in outcomes in this challenging condition.

Clinical guidelines for the treatment of congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a birth defect of the diaphragm in which abdominal organs herniate through the defect into the thoracic cavity. The main pathophysiology is respiratory distress and persistent pulmonary hypertension because of pulmonary hypoplasia caused by compression of the elevated organs. Recent progress in prenatal diagnosis and postnatal care has led to an increase in the survival rate of patients with CDH. However, some survivors experience mid- and long-term disabilities and complications requiring treatment and follow-up. In recent years, the establishment of clinical practice guidelines has been promoted in various medical fields to offer optimal medical care, with the goal of improvement of the disease' outcomes, thereby reducing medical costs, etc. Thus, to provide adequate medical care through standardization of treatment and elimination of disparities in clinical management, and to improve the survival rate and mid- and long-term prognosis of patients with CDH, we present here the clinical practice guidelines for postnatal management of CDH. These are based on the principles of evidence-based medicine using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The recommendations are based on evidence and were determined after considering the balance among benefits and harm, patient and society preferences, and medical resources available for postnatal CDH treatment.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Optimal timing of surgery in infants with prenatally diagnosed isolated left-sided congenital diaphragmatic hernia: a multicenter, cohort study in Japan

PURPOSE

To date, there is no compelling evidence of the optimal timing of surgery for congenital diaphragmatic hernia (CDH). This study aimed to establish the optimal timing of surgery in neonates with isolated left-sided CDH.

METHODS

This multicenter cohort study enrolled 276 patients with isolated left-sided CDH at 15 institutions. Based on the timing of surgery, the patients were classified into four groups [< 24 h (G1), 24-47 h (G2), 48-71 h (G3), and ≥ 72 h (G4)]. The clinical outcomes were compared among the groups using a logistic regression model, after adjusting for potential confounders, such as disease severity.

RESULTS

Multivariate analyses showed that G2 also had a lower mortality rate than the other groups. In mild and severe cases, there were no significant differences in mortality across the four groups. In moderate cases, G2 resulted in significantly increased survival rates, compared with G1.

CONCLUSION

The study results suggest that surgery within 24 h of birth is not recommended for patients with moderate severity CDH, that there is no benefit in the delay of surgery for more than 72 h in mild severity CDH patients, and that there is no definite optimal time to perform surgery in severe cases of CDH.

Review shows that implementing a nationwide protocol for congenital diaphragmatic hernia was a key factor in reducing mortality and morbidity

The French Rare Disease Reference Center for congenital diaphragmatic hernia (CDH) was created in 2008, to implement a national protocol for foetuses and children with this serious condition. Neonatal mortality from CDH is 30-40%, mainly due to pulmonary hypoplasia and persistent pulmonary hypertension, and half of those who live have high respiratory, nutritional and digestive morbidity. CDH management requires long-term and specialised multidisciplinary care. It has been well established that a standardised management protocol improves the prognosis of children with CDH.

CONCLUSION

Organising health care and implementing a nationwide French protocol were key factors for reducing mortality and morbidity from CDH.

Extracorporeal membrane oxygenation in infants with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a severe congenital anomaly which impairs normal pulmonary development leading to acute and chronic respiratory failure, pulmonary hypoplasia, pulmonary hypertension, and mortality. CDH is the most common non-cardiac indication for neonatal ECMO. Prenatal and postnatal predictors of CDH severity aid in patient selection. Centers vary in preferred mode of ECMO and timing of CDH repair. Survivors of severe CDH with ECMO are at risk for long-term sequelae including neurodevelopmental delays.

Impact of Objective Echocardiographic Criteria for Timing of Congenital Diaphragmatic Hernia Repair

OBJECTIVE

To assess the impact of specific echocardiographic criteria for timing of congenital diaphragmatic hernia repair on the incidence of acute postoperative clinical decompensation from pulmonary hypertensive crisis and/or acute respiratory decompensation, with secondary outcomes including survival to discharge, duration of ventilator support, and length of hospitalization.

STUDY DESIGN

The multidisciplinary congenital diaphragmatic hernia management team instituted a protocol in 2012 requiring the specific criterion of echocardiogram-estimated pulmonary artery pressure ≤80% systemic blood pressure before repairing congenital diaphragmatic hernias. A retrospective review of 77 neonatal patients with Bochdalek hernias repaired between 2008 and 2015 were reviewed: group 1 included patients repaired before protocol implementation (n = 25) and group 2 included patients repaired after implementation (n = 52).

RESULTS

The groups had similar baseline characteristics. Postoperative decompensation occurred less often in group 2 compared with group 1 (17% vs 48%, P = .01). Adjusted analysis accounting for repair type, liver herniation, and prematurity yielded similar results (15% vs 37%, P = .04). Group 2 displayed a trend toward improved survival to 30 days postoperatively, though this did not reach statistical significance (94% vs 80%, P = .06). Patient survival to discharge, duration of ventilator support, and length of hospitalization were not different between groups.

CONCLUSIONS

The implementation of a protocol requiring echocardiogram-estimated pulmonary arterial pressure ≤80% of systemic pressure before congenital diaphragmatic hernia repair may reduce the incidence of acute postoperative decompensation, although there was no difference in longer-term secondary outcomes, including survival to discharge.

Appropriate timing of surgery for neonates with congenital diaphragmatic hernia: early or delayed repair?

PURPOSE

This study was aimed to evaluate the influence of timing of surgery on patient outcomes, and to clarify appropriate timing of surgery in neonates with congenital diaphragmatic hernia (CDH).

METHODS

A total of 477 neonates with isolated CDH were included. Patients were classified into two groups by timing of surgery: early repair (ER) (≤48 h) and delayed repair (DR) (>48 h). The primary outcome was 90-day survival, with treatment duration (ventilation, oxygen, and hospitalization) being a secondary outcome. To adjust for disease severity, patients were stratified into three severities by Apgar score 1 min ("mild" 8-10, "moderate" 4-7, and "severe" 0-3), and outcomes were compared between ER and DR within each severity.

RESULTS

Although 90-day survival was significantly different among the three severities ("mild" 97%, "moderate" 89%, and "severe" 76%, p = 0.002), there were no differences in 90-day survival between DR and ER within each severity. In "mild", there were no differences in treatment duration between ER and DR. In "moderate", treatment duration was shorter in ER than DR (ventilation 11 vs. 16 days, oxygen 15 vs. 20 days, and hospitalization 34 vs. 48 days). In "severe", treatment duration was shorter in ER than DR, while the best OI was higher in DR than ER.

CONCLUSIONS

Timing of CDH repair seems to have no influence on 90-day survival regardless of disease severity. Patients with moderate severity may benefit from the early repair by reducing treatment duration.

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

OBJECTIVE

Variable management practices complicate the identification of optimal strategies for infants with congenital diaphragmatic hernia (CDH). This review critically appraises the available evidence to provide recommendations.

METHODS

Six questions regarding CDH management were generated. English language articles published between 1980 and 2014 were compiled after searching Medline, Cochrane, Embase and Web of Science. Given the paucity of literature on the subject, all studies irrespective of their rank in the levels of evidence hierarchy were included.

RESULTS

Gentle ventilation with permissive hypercapnia provides the best outcomes. Initial high frequency ventilation may be considered but its overall efficacy is unproven. Routine inhaled nitric oxide (iNO) or other medical adjuncts for acute, severe pulmonary hypertension demonstrate no benefit. Evidence does not support routine administration of pre- or postnatal glucocorticoids. Mode of extracorporeal membrane oxygenation (ECMO) has little bearing on outcomes. While the overall timing of repair does not impact outcomes, early repair on ECMO has benefits. Open repair leads to significantly fewer recurrences. Polytetrafluoroethylene (PTFE) is the most durable patch repair material.

CONCLUSIONS

Limited high-level evidence prevents the development of robust management guidelines for CDH. Prospective, multi-institutional studies are needed to identify best practices and optimize outcomes.

Controversies in the management of severe congenital diaphragmatic hernia

Despite years of progress in perinatal care, severe congenital diaphragmatic hernia (CDH) remains a clinical challenge. Controversies include almost every facet of clinical care: the definition of severe CDH by prenatal and postnatal criteria, fetal surgical intervention, ventilator management, pulmonary hypertension management, use of extracorporeal membrane oxygenation, surgical considerations, and long-term follow-up. Breakthroughs are likely only possible by sharing of experience, collaboration between institutions and innovative therapies within well-designed multicenter clinical trials.

Long-term maturation of congenital diaphragmatic hernia treatment results: toward development of a severity-specific treatment algorithm

OBJECTIVES

To assess the impact of varying approaches to congenital diaphragmatic hernia (CDH) repair timing on survival and need for ECMO when controlled for anatomic and physiologic disease severity in a large consecutive series of patients with CDH.

BACKGROUND

Our publication of 60 consecutive patients with CDH in 1999 showed that survival was significantly improved by limiting lung inflation pressures and eliminating hyperventilation.

METHODS

We retrospectively reviewed 268 consecutive patients with CDH, combining 208 new patients with the 60 previously reported. Management and ventilator strategy were highly consistent throughout. Varying approaches to surgical timing were applied as the series matured.

RESULTS

Patients with anatomically less severe left liver-down CDH had significantly increased need for ECMO if repaired in the first 48 hours, whereas patients with more severe left liver-up CDH survived at a higher rate when repair was performed before ECMO. Overall survival of 268 patients was 78%. Survival was 88% for those without lethal associated anomalies. Of these, 99% of left liver-down CDH survived, 91% of right CDH survived, and 76% of left liver-up CDH survived.

CONCLUSIONS

This study shows that patients with anatomically less severe CDH benefit from delayed surgery whereas patients with anatomically more severe CDH may benefit from a more aggressive surgical approach. These findings show that patients respond differently across the CDH anatomic severity spectrum and lay the foundation for the development of risk-specific treatment protocols for patients with CDH.

Trends in the treatment and outcome of congenital diaphragmatic hernia over the last decade

PURPOSE

Congenital diaphragmatic hernia (CDH) remains a challenging and life-threatening congenital anomaly. The aim was to evaluate whether treatment and survival has changed during the last decade.

METHODS

We retrospectively analysed all consecutive infants with CDH referred to two European tertiary paediatric surgical centres over 11 years (January 1999 to December 2009). Minimum follow-up was 1 year. χ(2) test for trend was used to evaluate significance.

RESULTS

There were 234 infants. There was no significant variation over time in the proportion of infants receiving high frequency oscillatory ventilation (HFOV) (p = 0.89), inhaled nitric oxide (iNO) (p = 0.90) or extracorporeal membrane oxygenation (ECMO) (p = 0.22). 205 infants (88 %) were stabilised and underwent surgical repair; of these, 186 (79 %) survived after surgery. Over time there was a significant increase in the proportion of infants undergoing surgical repair (p = 0.018) without a concomitant significant improvement in survival (p = 0.099).

CONCLUSION

This multicentre analysis indicates that the survival rate of infants with CDH referred to two European paediatric surgical centres is high (79 %). The use of HFOV, iNO and ECMO has not changed in recent years. We observed a significant increase in the proportion of infants who undergo surgery but this has not resulted in a significant increase in the overall survival rate.

Innovations in the surgical management of congenital diaphragmatic hernia

Surgical management of congenital diaphragmatic hernia (CDH) remains a challenge for all clinicians. While the treatment strategies for CDH have evolved from emergent surgical intervention to initial hemodynamic stabilization with delayed surgical repair, surgical innovations have remained limited in the last 20 years. Advances in surgical approaches, such as minimally invasive surgery and alternatives to diaphragmatic replacement, have focused on improvements in surgical morbidity.

Pulmonary development considerations in the surgical management of congenital diaphragmatic hernia

Congenital diaphragmatic hernia remains a clinical challenge for both neonatologists and pediatric surgeons. Advancements in mechanical ventilation strategies and neonatal intensive care have improved survival and transformed treatment of congenital diaphragmatic hernia from emergent surgery to early stabilization of the newborn followed by delayed repair of the diaphragmatic defect. Surgical technique has evolved and minimally invasive surgical approaches to close the diaphragmatic defect in these babies will likely improve with increasing experience. Finally, as more patients are diagnosed prenatally, attempts have been made to close the diaphragmatic defect prenatally. Unfortunately, this approach did not change the outcome of affected babies. Recently, progress has been made with prenatal tracheal plugging to improve prenatal lung development. In the near future experimental studies will start to explore new ways of treating affected babies prior to birth. This article reviews the evolution of the current treatment strategies in congenital diaphragmatic hernia and its future directions.

Congenital diaphragmatic hernia: still a moving target

The primary therapeutic target for congenital diaphragmatic hernia (CDH) patients has shifted from emergency surgical repair towards a non-operative emergency of the newborn treated by interdisciplinary teams. The increased understanding of the epidemiological and pathophysiological aspects of CDH have led to an improved knowledge and application of prenatal diagnosis, postnatal ventilation strategies, treatment of associated pulmonary hypertension and the role of extracorporeal membrane oxygenation therapy. In the surgical field, the perspectives have changed with delayed CDH repair, the introduction of minimally invasive surgery and use of prosthetic material for closure of large defects. With decreased mortality, long term multi-organ morbidity has increased in some survivors. In the near future, randomized controlled trials on different aspects of therapy will determine evidence-based optimal care.

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.

Neonatal endosurgical congenital diaphragmatic hernia repair: a systematic review and meta-analysis

OBJECTIVE

To compare outcomes of open and endosurgical neonatal congenital diaphragmatic hernia (CDH) repairs.

BACKGROUND

Historically a surgical emergency, neonatal CDH repair is now deferred pending stabilization of characteristically labile cardiopulmonary physiology. Usually accomplished via laparotomy, surgical repair may acutely worsen lung function; conversely, by reducing the visceral hernia, surgery might improve it. Theoretically, endosurgical repair could minimize deleterious effects of surgery while garnering benefits from decompressing the CDH lung. As endosurgical repair gains popularity, it is important to investigate whether or not minimally-invasive neonatal CDH repair has benefits.

METHODS

We searched Medline, Embase, and Cochrane Trials databases for studies comparing open with endosurgical CDH repair. Non-neonatal series and reports without comparison groups were excluded. References from papers and conference proceedings were also hand searched. Meta-analysis used a fixed effects model and was reported in accordance with PRISMA.

RESULTS

We included 3 studies (1 unpublished; none randomized); all compared thoracoscopic and open CDH repair and together described 143 patients. All studies had limitations, including use of historical controls. Demographics, CDH sidedness, APGAR and associated anomaly prevalence were similar between groups. For endosurgical repair, recurrence was higher (RR: 3.2 [1.1, 9.3], P = 0.03) and operative time longer (WMD 50 minutes [32, 69], P < 0.00001). Survival and patch usage were not different between open and endosurgical groups.

CONCLUSIONS

Neonatal thoracoscopic CDH repair has greater recurrence rates and operative times but similar survival and patch usage compared with open surgery. A prospective registry for all such cases would guide development of trials (Stage 2b; IDEAL recommendations).

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.

Factors associated with survival in infants with congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation: a report from the Congenital Diaphragmatic Hernia Study Group

OBJECTIVE

To identify factors associated with survival in patients with congenital diaphragmatic hernia (CDH) treated with extracorporeal membrane oxygenation (ECMO).

METHODS

We retrospectively analyzed the data on 3100 patients with CDH in the Congenital Diaphragmatic Hernia Study Group from 82 participating pediatric surgical centers (1995-2004). Covariates considered included prenatal and perinatal clinical information, specifics of surgical repair, and the duration of extracorporeal support.

RESULT

Nine hundred seven patients from the registry were identified as having been both managed with ECMO and undergone attempted surgical repair. The survival rate for the entire Congenital Diaphragmatic Hernia Study Group registry was 67% and 61% for those receiving ECMO in whom repair was attempted (P < .001). Among ECMO-treated children, survivors had a greater estimated gestational age (38 +/- 2 vs 37 +/- 2 weeks; P < .01), greater birth weights (3.2 +/- 0.5 vs 2.9 +/- 0.5 kg; P < .001), were less often prenatally diagnosed (53% vs 63%; P < .01), and were on ECMO for a shorter period of time (9 +/- 5 vs 12 +/- 5 days; P < .001). In logistic regression models, therapy-related variables, including the duration of ECMO, the nature of diaphragmatic repair, and the type of abdominal closure and certain comorbidities, particularly the presence of a concomitant severe cardiac abnormality, were independently associated with outcome.

CONCLUSION

Our model identifies a group of pre-surgical and postsurgical parameters that predict survival rate in patients with CDH on ECMO support. This model was derived from the retrospective data from a large database and will need to be prospectively tested.

The long-term follow-up of patients with a congenital diaphragmatic hernia: a broad spectrum of morbidity

Congenital diaphragmatic hernia (CDH) is a life-threatening anomaly with a mortality rate of approximately 40-50%, depending on case selection. It has been suggested that new therapeutic modalities such as nitric oxide (NO), high frequency oxygenation (HFO) and extracorporal membrane oxygenation (ECMO) might decrease mortality associated with pulmonary hypertension and the sequelae of artificial ventilation. When these new therapies indeed prove to be beneficial, a larger number of children with severe forms of CDH might survive, resulting in an increase of CDH-associated complications and/or consequences. In follow-up studies of infants born with CDH, many complications including pulmonary damage, cardiovascular disease, gastro-intestinal disease, failure to thrive, neurocognitive defects and musculoskeletal abnormalities have been described. Long-term pulmonary morbidity in CDH consists of obstructive and restrictive lung function impairments due to altered lung structure and prolonged ventilatory support. CDH has also been associated with persistent pulmonary vascular abnormalities, resulting in pulmonary hypertension in the neonatal period. Long-term consequences of pulmonary hypertension are unknown. Gastro-esophageal reflux disease (GERD) is also an important contributor to overall morbidity, although the underlying mechanism has not been fully understood yet. In adult CDH survivors incidence of esophagitis is high and even Barrett's esophagus may ensue. Yet, in many CDH patients a clinical history compatible with GERD seems to be lacking, which may result in missing patients with pathologic reflux disease. Prolonged unrecognized GERD may eventually result in failure to thrive. This has been found in many young CDH patients, which may also be caused by insufficient intake due to oral aversion and increased caloric requirements due to pulmonary morbidity. Neurological outcome is determined by an increased risk of perinatal and neonatal hypoxemia in the first days of life of CDH patients. In patients treated with ECMO, the incidence of neurological deficits is even higher, probably reflecting more severe hypoxemia and the risk of ECMO associated complications. Many studies have addressed the substantial impact of the health problems described above, on the overall well-being of CDH patients, but most of them concentrate on the first years after repair and only a few studies focus on the health-related quality of life in CDH patients. Considering the scattered data indicating substantial morbidity in long-term survivors of CDH, follow-up studies that systematically assess long-term sequelae are mandatory. Based on such studies a more focused approach for routine follow-up programs may be established.

Congenital diaphragmatic hernia: a systematic review and summary of best-evidence practice strategies

OBJECTIVES

Recent reports suggest that specific care strategies improve survival of infants with congenital diaphragmatic hernia (CDH). This review presents details of care from centers reporting high rates of survival among CDH infants.

STUDY DESIGN

We conducted a MEDLINE search (1995 to 2006) and searched all citations in the Cochrane Central Register of Controlled Trials. Studies were included if they contained reports of >20 infants with symptomatic CDH, and >75% survival of isolated CDH.

RESULT

Thirteen reports from 11 centers met inclusion criteria. Overall survival, including infants with multiple anomalies, was 603/763 (79%; range: 69 to 93%). Survival for isolated CDH was 560/661 (85%; range: 78 to 96%). The frequency of extracorporeal membrane oxygenation (ECMO) use for isolated CDH varied widely among reporting centers 251/622 (40%; range: 11 to 61%), as did survival for infants with isolated CDH placed on ECMO: 149/206 (73%; range: 33 to 86%). There was no suggestion of benefit from use of antenatal glucocorticoids given after 34 weeks gestation or use of postnatal surfactant. Low mortality was frequently attributed to minimizing lung injury and adhering to center-specific criteria for ECMO.

CONCLUSION

Use of strategies aimed at minimizing lung injury, tolerance of postductal acidosis and hypoxemia, and adhering to center-specific criteria for ECMO were strategies most consistently reported by successful centers. The literature lacks randomized clinical trials of these or other care strategies in this complex patient population; prospective studies of safety and long-term outcome are needed.

Retrospective study of 111 cases of congenital diaphragmatic hernia treated with early high-frequency oscillatory ventilation and presurgical stabilization

BACKGROUND

The prognosis of babies with congenital diaphragmatic hernia (CDH) remains unsatisfactory despite recent advances in medical and surgical treatment. Most authors agree that the best way to improve outcomes for this disease is to focus on pulmonary hypoplasia and persistent pulmonary hypertension (PPH), the 2 most unfavorable prognostic factors for patient survival. However, controversy remains regarding the best treatment of CDH. In the past decade, several institutions have developed treatment protocols that include high-frequency oscillatory ventilation (HFOV), preoperative stabilization, and no thoracic drain. This strategy is 1 of several "gentle ventilation" strategies. We describe our 10-year experience in treating a cohort of 111 infants with CDH managed with this "gentle ventilation" strategy.

METHODS

From October 1994 to June 2005, 111 babies with CDH were treated at our institution with HFOV. Babies progressed to inhaled nitric oxide and extracorporeal membrane oxygenation if severe PPH persisted. After a period of preoperative stabilization, surgery was performed via an abdominal approach. In case of large defects or diaphragmatic agenesis, a prosthetic patch was used. No thoracic drain was left in place at the end of surgery. The charts of all babies were reviewed. General characteristics, respiratory management, as well as perioperative and postoperative data were analyzed and correlated with survival. Predicted and actual survival rates in high-, intermediate-, and low-risk groups were analyzed on the basis of the equation described by the Congenital Diaphragmatic Hernia Study Group in 2001.

RESULTS

The overall survival rate in our group of patients with CDH was 69.4% regardless of side of the defect. Incidence of a prenatal diagnosis before the 25th gestational week, coexistence of severe congenital heart disease (overall incidence, 5.4%), or other major associated anomalies, as well as the presence of a diaphragmatic agenesis were significantly higher in nonsurvivors. Thirty-six had severe PPH, of which 26 (76.5% of nonsurviving patients) died. Survivors and nonsurvivors had significant differences in blood gas analysis and respiratory management data recorded before and after the diaphragmatic correction. Ninety-nine (89%) patients underwent correction of the diaphragmatic defect. A patch was used in 44 (44%) patients and 15 of them died (survivors, 37.7%; nonsurvivors, 68.2%; P = .0111). Six (43%) of 14 patients with a preoperative pneumothorax (survivors, 10.3%; nonsurvivors, 27.3%; P > .05) and 7 (58%) of 12 patients with a postoperative pneumothorax needing a thoracic drain (survivors, 6.5%; nonsurvivors, 31.8%; P = .0013) died. In all cases, pneumothorax was ipsilateral. Two patients required oxygen therapy at discharge. The predicted survival rate was 69%; there was no difference between predicted and actual overall survival as well as between predicted and actual survival in low-risk (predicted survival rate, >66%), intermediate-risk (predicted survival rate, 34%-66%), and high-risk (predicted survival rate, <33%) groups.

CONCLUSIONS

The CDH treatment strategy that includes HFOV, preoperative stabilization and no thoracic drain ensures survival with minimal pulmonary morbidity (low rate of pulmonary infections and low rate of patients requiring oxygen at home) in most affected babies. Persistent pulmonary hypertension has been the most challenging factor that ultimately determined the final outcome, and availability of new vasoactive drugs is mandatory to ameliorate the prognosis especially in high-risk patients. Meanwhile, survival comparisons of low-, intermediate-, and high-risk groups between institutions using different protocols will allow the identification of the best strategy for CDH management.

Surgical management of neonates with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is one of the most challenging and complex pediatric abnormalities to manage, both medically and surgically. The care of these neonates has seen significant evolution, from previous aggressive ventilation and emergent operation to current permissive hypercapnea, physiologic stabilization, and elective surgical repair, all in less than two decades. These changes have led to many centers reporting survival rates near 80%, a dramatic improvement from the 50% survival reported in the 1970s. This review covers the current principles guiding the surgical management of CDH in the neonate, including preoperative stabilization, operative timing, extracorporeal membrane oxygenation, surgical approach, and management of recurrence. Although many clinical challenges remain, multi-institutional collaboration and ongoing research efforts will hopefully improve the clinical care of these patients.

Matching ventilatory support strategies to respiratory pathophysiology

Neonates can suffer from various diseases that impact differently on lung function according to the specific pulmonary pathophysiology. As a consequence, the optimal respiratory support will vary according to disorder. Most randomized trials have only included prematurely born infants who have respiratory distress syndrome (RDS) or infants who have severe respiratory failure. Meta-analysis of the results has demonstrated that for the prematurely born infant who has RDS, prophylactic high-frequency oscillatory ventilation only results in a modest reduction in bronchopulmonary dysplasia, and patient-triggered ventilation (assist/control or synchronized intermittent mandatory ventilation) reduces the duration of ventilation if started in the recovery phase. Whether the newer triggered modes are more efficacious remains to be appropriately tested. In term infants who have severe respiratory failure, extracorporeal membrane oxygenation increases survival, but inhaled nitric oxide only reduces the need for extracorporeal membrane oxygenation. Research is required to identify the optimum respiratory strategy for infants who have other respiratory disorders, particularly bronchopulmonary dysplasia.

Prevention of heart failure in the management of congenital diaphragmatic hernia by maintaining ductal patency. A case report

Congenital diaphragmatic hernia is a rare entity in childhood carrying a high mortality rate of 30% to 50%. Ipsilateral pulmonary hypoplasia, increased pulmonary vascular resistance, and potential cardiac failure complicate early postnatal life. Surgical correction can either be performed on the first day of life or be deferred to a time after stabilization of the infant. Our patient presented with a left-sided Bochdalek's hernia containing large and small bowel. She required intubation and resuscitation on day 1 of life, and surgical repair had to be postponed. Further respiratory deterioration required commencement of inhaled nitric oxide and high-frequency ventilation. Pulmonary artery pressure rose to suprasystemic level. Closure of the ductus arteriosus on day 8 resulted in imminent right-sided heart failure. Commencement of alprostadil (prostaglandin E1) reopened the ductus and stabilized the patient. Surgical repair was successful 3 days later. Alprostadil should be considered as an important component of therapy in severe cases of congenital diaphragmatic hernia, where deterioration of right-sided heart function occurs.

Liver position in fetal congenital diaphragmatic hernia retains a prognostic value in the era of lung-protective strategy

BACKGROUND/PURPOSE

The aims of this study were to analyze the outcomes of fetuses with congenital diaphragmatic hernia (CDH) treated by a lung-protective strategy using high-frequency oscillatory ventilation (HFOV) in a single center with a perinatology service and extracorporeal membrane oxygenation (ECMO) capability and to define the natural history of CDH in the era of lung-protective ventilation.

METHODS

A retrospective chart review of 30 neonates with CDH seen between April 2002 and October 2004 was conducted. All fetuses with a prenatal diagnosis were evaluated by fetal magnetic resonance imaging to define the liver position, and those with a significant volume of the liver in the chest were regarded as liver-up. Patients were managed by a lung-protective strategy using pressure-limited (maximum mean airway pressure [MAP], 18 cm H(2)O) HFOV. The patients were initially placed on HFOV with a fraction of inspired oxygen (Fio(2)) of 1.0 and a MAP of 12 cm H(2)O. Hypercapnea and preductal saturation as low as 85% were accepted. Inhaled nitric oxide and ECMO were introduced when the baby could not be oxygenated with a MAP of 18 cm H(2)O.

RESULTS

Twenty-six neonates (22 inborns with prenatal diagnosis and 4 outborns) were treated with this protocol. Four cases were not treated or died in utero because of severe associated anomalies. Thirteen of the 14 liver-down cases survived without ECMO and were discharged home (93% survival). On the contrary, 4 of 12 liver-up cases survived (33% survival). ECMO was required for initial stabilization in 5 cases with 1 survivor.

CONCLUSIONS

Liver-down CDH babies have a good chance for survival without ECMO by a planned delivery and the lung-protective strategy using HFOV. Liver herniation demonstrated by prenatal magnetic resonance imaging retains a poor prognostic value even with this approach.

Optimal strategies for newborn ventilation--a synthesis of the evidence

A variety of ventilation modes are available for the newborn. Although, there have been randomised trials assessing certain modes, these have generally only included prematurely born infants with RDS or infants with severe respiratory failure. Meta-analysis of the results of those trials has demonstrated that neither patient triggered nor high frequency oscillatory ventilation is advantageous for the prematurely born infant with RDS, but extracorporeal membrane oxygenation increases survival in infants with severe respiratory failure. Appropriately designed studies are required to determine the role of newer ventilation modes and whether forms of respiratory support avoiding intubation are less injurious to the lungs. Research should also focus on infants with other respiratory disorders, particularly BPD. Prior to further randomised trials being undertaken, it is essential that the optimum method of applying each ventilator mode is identified and it is clearly understood whether differences in ventilator/oscillator performance influence outcome.

Thoracoscopic repair of congenital diaphragmatic hernia by inflation-assisted bowel reduction, in a resuscitated neonate: a better access?

Elective endoscopic diaphragmatic hernia repairs have been reported. But endoscopic surgery was regarded unsuitable for emergency repair of diaphragmatic hernia in ventilated newborn children in bad general condition. We report a new method for inflation-assisted reduction and thoracoscopic repair of congenital diaphragmatic hernia diaphragmatic in a vitally endangered neonate. From three 2.7 mm to 5 mm accesses warmed low-pressure, low-volume CO2 was inflated into the thorax at 100 ml/min and 2 mm mercury. This allowed spontaneous reduction of the thoracic viscera into the abdomen and diaphragmatic suture with minimal handling. The 65-min procedure was tolerated well without perioperative deterioration. The baby was weaned off the respirator and breast-fed within 2 days, mediastinal shift normalized in 6 days. In suitable infants thoracoscopic repair and inflation-assisted reduction of thoracic contents is a more physiological access to congenital diaphragmatic hernia than laparoscopy or laparotomy.

Evidence-based management of infants with congenital diaphragmatic hernia

The mortality rate associated with congenital diaphragmatic hernia (CDH) varies widely between centers and remains relatively high despite widespread use of new therapeutic modalities. Many of these have been implemented without properly controlled studies. Over the past 10 to 15 years, only 9 randomized trials enrolling a total of approximately 250 infants with CDH have been published. The limited evidence available suggests that better outcomes are observed by delivering infants with CDH at experienced centers, by delaying surgical repair until hemodynamic and respiratory stability is achieved, and by the judicious utilization of nonaggressive mechanical ventilation and permissive hypercapnea. Other therapeutic modalities, such as high frequency oscillatory ventilation, inhaled nitric oxide, and ECMO, may provide additional advantages for selected infants. There is a dire need to establish networks of centers that manage enough infants with CDH, to conduct appropriately sized randomized trials that can answer some of the critical questions about the management and long-term outcome of these infants.

New approaches to managing congenital diaphragmatic hernia

A number of new techniques have been studied for managing newborns with congenital diaphragmatic hernia and respiratory insufficiency. Among these have been the techniques of delayed approach to the repair of the diaphragmatic hernia; permissive hypercapnia; nitric oxide and surfactant administration; intratracheal pulmonary ventilation; liquid ventilation; perfluorocarbon-induced lung growth; and lung transplantation. These interventions are at various stages of development and evaluation of effectiveness. All, however, are being explored in the hopes of improving outcome in patients with congenital diaphragmatic hernia who continue to have significant morbidity and mortality in the newborn period.

Factors influencing survival in newborns with congenital diaphragmatic hernia: the relative role of timing of surgery

PURPOSE

Controversy persists regarding the factors influencing survival in patients with congenital diaphragmatic hernia (CDH), in particular, the role of timing of surgery. The authors therefore sought to determine such factors and to assess the relative role of timing of surgery on outcome.

METHODS

All CDH newborns 1991 through 2002 (n = 111) were divided into those undergoing repair before ("early" n = 35), or after ("late" n = 76) 48 hours. A multivariate analysis was performed to determine the relative impact of various factors on survival rate.

RESULTS

Overall survival rate was 64%. There was no effect on survival of heart rate, temperature, systolic blood pressure, age, extracorporeal membrane oxygenation use, mesh use, infections, or intracranial hemorrhage, and there was no difference between early (68%) or late (62%) repair (P =.2). Initial pCO2 greater than 50, pO2 less than 40, cardiac defects, or renal failure significantly decreased survival rate.

CONCLUSIONS

Significant factors influencing survival rate in patients with CDH include cardiac defects, renal failure, and the initial blood gases and not the timing of surgery. CDH repair should be based on the optimization of clinical parameters as opposed to a specific time period to improve outcome.

Congenital diaphragmatic hernia: a survey of practice in Scandinavia

There is no consensus on the treatment of congenital diaphragmatic hernia (CDH), and practice seems to vary between centres. The main purpose of the present study was to survey current practice in Scandinavia. Thirteen paediatric surgical centres serving a population of about 22 million were invited, and all participated. One questionnaire was completed at each centre. The questionnaire evaluated management following prenatal diagnosis, intensive care strategies, operative treatment, and long-term follow-up. Survival data (1995-1998) were available from 12 of 13 centres. Following prenatal diagnosis of CDH, vaginal delivery and maternal steroids were used at eight and six centres, respectively. All centres used high-frequency oscillation ventilation (HFOV), nitric oxide (NO), and surfactant comparatively often. Five centres had extracorporeal membrane oxygenation (ECMO) facilities, and four centres transferred ECMO candidates. The majority of centres (7/9) always tried HFOV before ECMO was instituted. Surgery was performed when the neonate was clinically stable (11/13) and when no signs of pulmonary hypertension were detected by echo-Doppler (6/13). The repair was performed by laparotomy at all centres and most commonly with nonabsorbable sutures (8/13). Thoracic drain was used routinely at seven centres. Long-term follow-up at a paediatric surgical centre was uncommon (3/13). Only three centres treated more than five CDH patients per year. Comparing survival in centres treating more than five with those treating five or fewer CDH patients per year, there was a tendency towards better survival in the higher-volume centres (72.4%) than in the centres with lower volume (58.7%), p =0.065.

Apparent truth about congenital diaphragmatic hernia: a population-based database is needed to establish benchmarking for clinical outcomes for CDH

BACKGROUND

The authors hypothesize that recent single or multiinstitution-based reports of improved survival of congenital diaphragmatic hernia (CDH) patients are biased by patient selection, practice, and referral patterns. Here the authors report a population-based analysis of the clinical outcomes of CDH in the province of Ontario for 1996.

METHODS

A retrospective analysis of cross-sectional data from the Bureau of Vital Statistics of Ontario and all 5 pediatric surgical institutions in Ontario for 1996 was performed.

RESULTS

Twenty-four CDH-associated deaths were registered in Canada in 1996. Fourteen of 24 occurred in Ontario (58.3%). Of 30 institutionally identified CDH in Ontario, 8 patients died (26.7%). CDH-associated infant mortality rate was 6.6 of 100,000 live births in Canada compared with 10 of 100,000 live births for Ontario (Relative risk, 1.4; confidence interval, 0.5, 3.7; P >.01). Neonatal death (<28 postnatal days) accounted for the majority, 13 of 14 (92.8%) of deaths. Six of 14 (42.9%) CDH-associated deaths, however, were not accounted by the institutional-based reporting. In addition, institutional-based survival rates for CDH varied from 62.5% to 100%.

CONCLUSIONS

Our results indicate the existing bias associated with institution-based reporting and database of CDH. The "hidden mortality" associated with CDH is still present. A population-based database is needed to establish the benchmarking for management of CDH.

Congenital Diaphragmatic Hernia Repair on Extracorporeal Life Support: A Decade of Lessons Learned

Congenital diaphragmatic hernia (CDH) is a vexing anomaly that manifests with variable pulmonary compromise in neonates. More than one-third of neonates with CDH require extracorporeal membrane oxygenation (ECMO) for refractory pulmonary hypertension (PHN). To assess the outcome of neonates having CDH repair on ECMO, we reviewed our experience for babies treated between 1992 and 2003. Of 97 neonates with CDH, 40 required ECMO, and 30 were repaired on bypass. Eighteen were supported by veno-venous bypass (VV) and 12 by veno-arterial bypass (VA). While on ECMO, transfusion requirements increased twofold postoperatively (15 to 33 cc · kg-1 · day-1, P = 0.03) and then significantly decreased after decannulation (1.5 cc · kg-1 · day-1, P < 0.01). Non-intracranial hemorrhage occurred in 7 (23%) infants and intracranial hemorrhage in 3 (10%). Twelve (40%) infants died; one (3%) on ECMO secondary to refractory PHN. The mean length of stay for the 18 (60%) survivors was 48 days. Comparisons between survivors and nonsurvivors showed a significantly increased mortality for infants placed on VA bypass ( P < 0.01). However, no other variable was predictive of survival. We conclude that CDH repair on ECMO is technically feasible, shows similar survival to the Extracorporeal Life Support Organization (ELSO) registry, and is associated with few bleeding complications.

Congenital diaphragmatic hernia: advances in prenatal therapy

Despite intensive clinical and experimental efforts, mortality from CDH remains high. More than two decades of research in multiple centers has led to a better understanding of the pathophysiology, prognosis, and treatment options for fetuses that have CDH. It now appears that fetuses that have prenatally diagnosed CDH can be stratified into high- and low-risk groups based upon sonographic parameters. Fetuses that do not have liver herniation into the chest that have a favorable LHR have an excellent chance of survival with postnatal therapy. Prenatal diagnosis allows the time and place of delivery to be planned in advance so these infants can be treated in a tertiary care nursery that has maximal medical and surgical therapy. Fetuses that have liver herniation into the chest and an unfavorable LHR have a grim prognosis. These fetuses might benefit from in utero intervention. There is no role for open fetal repair of the diaphragmatic detect; however, fetoscopic temporary tracheal occlusion might improve lung growth and development and might decrease morbidity and mortality in these infants. The FETENDO strategy appears to work, and for the first time it offers hope to the fetus that has high-risk CDH, but its efficacy must be proven in a proper randomized, controlled trial.

A prospective, randomized pilot trial of perfluorocarbon-induced lung growth in newborns with congenital diaphragmatic hernia

BACKGROUND/PURPOSE

Initial laboratory and clinical data suggest that partial liquid ventilation (PLV) can enhance pulmonary function and that lung growth can be induced via distension of the newborn lung using perfluorocarbon in patients with congenital diaphragmatic hernia (CDH). The authors, therefore, performed a prospective, randomized pilot study evaluating PLV and perfluorocarbon-induced lung growth (PILG) in newborns with CDH on extracorporeal life support (ECLS) at 6 medical centers.

METHODS

Patients were selected randomly using a permuted block design to PLV/PILG (n = 8) or conventional mechanical ventilation (CMV/control, n = 5). Patients in the PILG group received daily doses which filled the lungs with perflubron for up to 7 days and were placed on continuous positive airway pressure of 5 to 8 cm H2O. CMV patients were treated with standard mechanical ventilation while on extracorporeal membrane oxygenation (ECMO).

RESULTS

A total of 13 patients were evaluated in this study. All 3 patients enrolled without being on ECLS rapidly transitioned to ECLS. The study, therefore, effectively evaluated PILG (n = 8) versus standard ventilation (control, n = 5) on ECLS. Mean (+/- SE) gestational age was 37 +/- 1 weeks and weight was 3.1 +/- 0.1 kg. Time on ECMO was 9.8 +/- 2.3 days in the PILG and 14.5 +/- 3.5 days (P =.58) in the control group. Survival rate in the PILG group was 6 of 8 (75%), whereas survival rate was 2 of 5 (40%) in the control group (P =.50). The number of days free from the ventilator in the first 28 days (VFD) was 6.3 +/- 3.3 days with PILG and 4.6 +/- 4.6 days with control (P =.9). Causes of death in the PILG group included sepsis and renal failure in one patient and pulmonary hypertension in the other. There were no safety issues, and the deaths in the PILG group did not appear to be related to the administration of perflubron.

CONCLUSIONS

These data show that PILG can be performed safely. The survival rate, VFD, and time on ECMO data, although not conclusive, are encouraging and indicate the need for a definitive trial of this novel intervention in these neonates with high mortality.

Perinatal management and outcome of prenatally diagnosed congenital diaphragmatic hernia: a 1995-2000 series in Rennes University Hospital

OBJECTIVES

To assess the prognosis of prenatally diagnosed congenital diaphragmatic hernia (CDH) during the years 1995-2000 in order to improve prenatal counselling.

METHODS

Retrospective study of all 31 cases of women with prenatally diagnosed CDH.

RESULTS

Nine pregnancies (29%) were terminated and two fetuses (6%) were stillborn. Ten fetuses (32%) had associated anomalies (four Fryns' syndrome) and four (13%) had underlying chromosomal anomalies. Twenty pregnancies were continued. Seven babies died before surgery either immediately in the delivery room (five between 1 and 45 min), or during the 'stabilisation period' (two babies, 7 and 21 h). Three babies presented with trisomy 18, Fryns' syndrome or transposition of the great arteries with microdeletion 22q11. Thirteen babies had the defect repaired (median 18 h, range 4-72 h) and 12 survived. Mechanical ventilation was required for a median of 12 days. One survivor has cerebral palsy.

CONCLUSION

Of 31 prenatally diagnosed CDH cases 38% are alive, of 20 ongoing pregnancies 60% are alive, and of 13 babies who underwent surgery 92% are alive. No baby with associated malformations survived. These numbers need to be known by each member of the counselling team in order to give parents adequate information to make their decision.

Using evidence-based medicine principles to improve quality of patient care in pediatric surgery

Evidence-based medicine (EBM) is defined strictly as "the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients." A requirement for the successful implementation of EBM principles, with the goal of improving patient care, is knowledge related to the hierarchy of evidence and other concepts. The highest level of evidence is produced from prospective, hypothesis-testing research protocols, which currently are rare in the pediatric surgery literature. There are obstacles to conducting these studies in pediatric surgery because of the rarity of many disease conditions; however, with careful planning and funding, such studies can and should be performed.

Outcome of congenital diaphragmatic hernia

The outcome of congenital diaphragmatic hernia (CDH) differs for different stages of the fetus or infant's life (i.e., antenatal, immediate postnatal, and postoperative). Assessing combined data from nonrandomized studies is technically difficult. Following recognized methods of reviewing such trials, we aimed to review the available literature on the outcome of CDH to provide a guide to clinicians when counselling parents who have a fetus/infant with this condition. Thirty-five studies reporting data for CDH from 1985 to March 1998 were identified using a high sensitive search strategy, hand-searching journals, and reviewing references of relevant studies. These were systematically reviewed. The median overall mortality was 58% (interquartile range (IQR), 43-65%) for babies diagnosed in utero, 48% (IQR, 35-55%) if born alive, and 33% (IQR, 18-54%) postoperatively. Diagnosis before 25 weeks of gestation is not a uniformly bad prognostic indicator (median mortality, 60%). Outcome was worse for those fetuses with other anomalies (median mortality, 93%). The median percentage mortality for all infants born alive and treated in extracorporeal membrane oxygenation (ECMO) centers was 34% (IQR, 26-47%). Median percentage mortality for all ECMO-treated infants was 44% (IQR, 35-50%). Different treatment strategies may have a variable impact on outcome. These figures, together with local data, may help in parental counselling on prognosis for fetuses/infants with CDH.

Congenital diaphragmatic hernia: a meta-analysis of mortality factors

PURPOSE

The aim of this study was to review all available studies reported in the English-language literature from 1975 through 1998, and by meta-analysis assess the importance of prenatal diagnosis, associated malformations, side of hernia, timing of surgery, and study population on mortality rates in patients with congenital diaphragmatic hernia (CDH).

METHODS

One-hundred-two studies were identified, and 51 studies (2,980 patients) fulfilled the prespecified inclusion criteria. Studies were grouped according to study population into: (I) fetuses diagnosed prenatally; (II) neonates admitted to a treatment center; and (III) population-based studies.

RESULTS

Pooled total mortality rate was significantly higher in category I than in category III (75.6% v 58.2%, P < .001). Pooled hidden postnatal mortality rate (deaths before admittance to a treatment center) in population-based studies was 34.9%. Prenatally diagnosed patients in both category II and III had significantly higher mortality rates than those diagnosed postnatally. Mortality rates were significantly higher among CDH infants with associated major malformations compared with isolated CDH in all 3 categories. An increased mortality rate in right-sided CDH was found in category II and III.

CONCLUSIONS

Prenatal diagnosis of CDH, presence of associated major malformations, and the study population have a major influence on mortality rate. The very high mortality rate in studies of fetuses with a prenatal diagnosis of CDH should be taken into account in prenatal counselling.

[Congenital hernia of the diaphragm. A retrospective study of 123 cases recorded in the Neonatal Medicine Department, URHC in Lille between 1985 and 1996]

BACKGROUND

During the last ten years, new therapeutic strategies have been used in order to improve the management of congenital diaphragmatic hernia (CDH). CDH is associated with pulmonary hypoplasia, abnormal pulmonary vascular reactivity and pulmonary immaturity. Between 1985 and 1990, mechanical hyperventilation and early surgery were provided systematically. Since 1991, the management of CDH in our institution has involved a preoperative stabilization with exogenous surfactant replacement, gentle ventilation, high-frequency oscillation, nitric oxide or extracorporeal membrane oxygenation.

PURPOSE

To analyse the impact of the new therapeutic strategy on the survival and outcome of newborns with CDH.

METHODS

Retrospective review of all infants with CDH admitted to our institution from 1985 through 1996. Mortality and morbidity were compared between period I (1985-1990) and period II (1991-1996).

RESULTS

Between 1985 and 1996, 123 neonates were admitted to our Neonatal Department. Nine of them had another severe congenital malformation and were excluded from the study. Survival was 23% (12/52) in period I and 56% (35/62) in period II (p < 0.001). In period II, complications were more frequent among survivors in whom an extracorporeal membrane oxygenation was required (13 infants): bronchopulmonary dysplasia 77% (10/13), gastroesophageal reflux 61% (8/13), and hypotrophy 61% (8/13).

CONCLUSION

These data demonstrate a significant improvement in survival in CDH since the implementation of new therapeutic modalities. Nevertheless, a significant morbidity exists among the infants who survive a severe respiratory failure.

Late versus early surgical correction for congenital diaphragmatic hernia in newborn infants

BACKGROUND

Congenital diaphragmatic hernia, although rare (1 per 2-4,000 births), is associated with high mortality and cost. Opinion regarding the timing of surgical repair has gradually shifted from emergent repair to a policy of stabilization using a variety of ventilatory strategies prior to operation. Whether delayed surgery is beneficial remains controversial.

OBJECTIVES

To summarize the available data regarding whether surgical repair in the first 24 hours after birth rather than later than 24 hours of age improves survival to hospital discharge in infants with congenital diaphragmatic hernia who are symptomatic at or immediately after birth.

SEARCH STRATEGY

Search of Medline (1966-1999), Embase (1978-1999) and the Cochrane databases using the terms "congenital diaphragmatic hernia" and "surg*"; citations search, and contact with experts in the field to locate other published and unpublished studies.

SELECTION CRITERIA

Studies were eligible for inclusion if they were randomized or quasi-randomized trials that addressed infants with CDH who were symptomatic at or shortly after birth, comparing early (<24 hours) vs late (>24 hours) surgical intervention, and evaluated mortality as the primary outcome.

DATA COLLECTION AND ANALYSIS

Data were collected regarding study methods and outcomes including mortality, need for ECMO and duration of ventilation, both from the study reports and from personal communication with investigators. Analysis was performed in accordance with the standards of the Cochrane Neonatal Review Group.

MAIN RESULTS

Two trials met the pre-specified inclusion criteria for this review. Both were small trials (total n<90) and neither showed any significant difference between groups in mortality. Meta-analysis was not performed because of significant clinical heterogeneity between the trials.

REVIEWER'S CONCLUSIONS

There is no clear support for either immediate (within 24 hours of birth) or delayed (until stabilized) repair of congenital diaphragmatic hernia, but a substantial advantage to either one cannot be ruled out. A large, multicenter randomized trial would be needed to answer this question.