Neurodevelopmental outcome after congenital diaphragmatic hernia: Extracorporeal membrane oxygenation before and after surgery

Brain development in newborns and infants after ECMO

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) not only significantly improves survival rates in severely ill neonates but also is associated with long-term neurodevelopmental issues. To systematically review the available literature on the neurodevelopmental outcomes of neonates and infants who have undergone ECMO treatment, with a focus on motor deficits, cognitive impairments, sensory impairments, and developmental delays. This review aims to understand the incidence, prevalence, and risk factors for these problems and to explore current nursing care and management strategies.

DATA SOURCES

A comprehensive literature search was performed across PubMed, EMBASE, and Web of Science using a wide array of keywords and phrases pertaining to ECMO, neonates, infants, and various facets of neurodevelopment. The initial screening involved reviewing titles and abstracts to exclude irrelevant articles, followed by a full-text assessment of potentially relevant literature. The quality of each study was evaluated based on its research methodology and statistical analysis. Moreover, citation searches were conducted to identify potentially overlooked studies. Although the focus was primarily on neonatal ECMO, studies involving children and adults were also included due to the limited availability of neonate-specific literature.

RESULTS

About 50% of neonates post-ECMO treatment exhibit varying degrees of brain injury, particularly in the frontal and temporoparietal white matter regions, often accompanied by neurological complications. Seizures occur in 18%-23% of neonates within the first 24 hours, and bleeding events occur in 27%-60% of ECMO procedures, with up to 33% potentially experiencing ischemic strokes. Although some studies suggest that ECMO may negatively impact hearing and visual development, other studies have found no significant differences; hence, the influence of ECMO remains unclear. In terms of cognitive, language, and intellectual development, ECMO treatment may be associated with potential developmental delays, including lower composite scores in cognitive and motor functions, as well as potential language and learning difficulties. These studies emphasize the importance of early detection and intervention of potential developmental issues in ECMO survivors, possibly necessitating the implementation of a multidisciplinary follow-up plan that includes regular neuromotor and psychological evaluations. Overall, further multicenter, large-sample, long-term follow-up studies are needed to determine the impact of ECMO on these developmental aspects.

CONCLUSIONS

The impact of ECMO on an infant's nervous system still requires further investigation with larger sample sizes for validation. Fine-tuned management, comprehensive nursing care, appropriate patient selection, proactive monitoring, nutritional support, and early rehabilitation may potentially contribute to improving the long-term outcomes for these infants.

Comorbidities and Late Outcomes in Neonatal Pulmonary Hypertension

Long-term outcomes of persistent pulmonary hypertension of newborn (PPHN) depend on disease severity, duration of ventilation, and associated anomalies. Congenital diaphragmatic hernia survivors may have respiratory morbidities and developmental delay. The presence of PPHN is associated with increased mortality in hypoxic-ischemic encephalopathy, though the effects on neurodevelopment are less clear. Preterm infants can develop pulmonary hypertension (PH) early in the postnatal course or later in the setting of bronchopulmonary dysplasia (BPD). BPD-PH is associated with higher mortality, particularly within the first year. Evidence suggests that both early and late PH in preterm infants are associated with neurodevelopmental impairment.

School age educational outcomes of infants born with congenital diaphragmatic hernia

BACKGROUND

To compare academic proficiency among children with congenital diaphragmatic hernia (CDH) versus controls and identify predictors of academic performance among children with CDH.

METHODS

Infants born with CDH in Arkansas, 2000-2005, were identified from the Arkansas Reproductive Health Monitoring System. For each case, two controls were selected from birth certificate data and matched for hospital and month of birth, sex, and race/ethnicity. Data on re-hospitalization within the first 5 years and payer data were collected from the Arkansas Hospital Inpatient Discharge database. Surviving cases and controls were linked to the Arkansas Department of Education database. Primary outcomes were odds of proficiency on fourth grade literacy and mathematics achievement tests. Multivariable logistic regression models evaluated the association between study characteristics and academic proficiency.

RESULTS

The final study cohort included 25 surviving CDH cases and 31 controls who were linked to their education data. After adjusting for differences in characteristics (5-min Apgar score and associated congenital anomalies) between cases and controls, there were no statistically significant differences in literacy (72% vs. 84%, p = .93) or mathematics (64% vs. 81%, p = .98) test proficiency between the two groups. In multivariable analyses, among CDH cases, oxygen at discharge and Medicaid payer/longer hospital stay were associated with worse fourth grade literacy and mathematics proficiency, respectively.

CONCLUSIONS

Oxygen at discharge, Medicaid payer, and longer hospital stay were associated with lower academic performance among CDH cases.

Unsolved problems in CDH follow-up

In patients affected by CDH, survival beyond the neonatal period continues to increase thanks to technological and pharmacological improvements. Conversely, patients, families and caregivers are more and more frequently facing "new" complex late comorbidities, including chronic pulmonary and cardiac dysfunctions, neurodevelopmental challenges, and specific nutritional requirements, that often require ongoing long-term medical or surgical care. Therefore, late morbidity is now a key focus in clinical care of CDH. The aims of this paper are to stress some of the most important "unsolved problems" for CDH patients at long-term follow-up.

Neurodevelopmental outcomes in children with isolated congenital diaphragmatic hernia: A systematic review and meta-analysis

BACKGROUND

Congenital diaphragmatic hernia (CDH) reportedly has neurologic consequences in childhood however little is known about the impact in isolated CDH.

AIMS

Herein we aimed to describe the risk of neurodevelopmental complications in children born with isolated CDH.

MATERIALS & METHODS

We systematically reviewed literature for reports on the neurological outcome of infants born with isolated CDH. The primary outcome was neurodevelopmental delay. Secondary outcomes included, motor skills, intelligence, vision, hearing, language and behavior abnormalities.

RESULTS

Thirteen out of 87 (15%) studies reported on isolated CDH, including 2624 out of 24,146 children. Neurodevelopmental delay was investigated in four studies and found to be present in 16% (3-34%) of children. This was mainly attributed to motor problems in 13% (2-30%), whereas cognitive dysfunction only in 5% (0-20%) and hearing in 3% (1-7%). One study assessed the effect of fetal surgery. When both isolated and non-isolated children were included, these numbers were higher.

DISCUSSION

This systematic review demonstrates that only a minority of studies focused on isolated CDH, with neurodevelopmental delay present in 16% of children born with CDH.

CONCLUSION

To accurately counsel patients, more research should focus on isolated CDH cases and examine children that underwent fetal surgery.

Neurodevelopmental impairment in children with congenital diaphragmatic hernia: Not an uncommon complication for survivors

PURPOSE

To evaluate neurodevelopmental impairment (NDI) in children born with congenital diaphragmatic hernia (CDH).

METHODS

Using a defined search strategy, a systematic review was conducted to define the incidence and types of NDI, to report abnormal neuroimaging findings and to evaluate possible NDI predictors. A meta-analysis was performed on comparative studies reporting risk factors for NDI, using RevMan 5.3.

RESULTS

Of 3541 CDH children (33 studies), 829 (23%) had NDI, with a higher incidence in CDH survivors who received ECMO treatment (49%) vs. those who had no ECMO (22%; p<0.00001). NDI included neuromuscular hypotonia (42%), hearing (13%) and visual (8%) impairment, neurobehavioral issues (20%), and learning difficulties (31%). Of 288 survivors that had postnatal neuroimaging, 49% had abnormal findings. The main risk factors for NDI were severe pulmonary hypoplasia, large defect size, ECMO use.

CONCLUSIONS

NDI is a relevant problem for CDH survivors, affecting 1 in 4. The spectrum of NDI covers all developmental domains and ranges from motor and sensory (hearing, visual) deficits to cognitive, language, and behavioral impairment. Further studies should be designed to better understand the pathophysiology of NDI in CDH children and to longitudinally monitor infants born with CDH to correct risk factors that can be modifiable.

LEVEL OF EVIDENCE

Level III.

Neurologic Outcomes in a Two-Center Cohort of Neonatal and Pediatric Patients Supported on Extracorporeal Membrane Oxygenation

Contemporary studies of long-term outcomes in children supported on extracorporeal membrane oxygenation (ECMO) in the United States are limited. We enrolled 99 ECMO patients between July 2010 and June 2015 in a two-center prospective observational study that included neurologic and neuropsychologic evaluation at 6 and 12 months, using standardized outcome measures. Pre-ECMO, 20 (20%) had a pre-existing neurologic diagnosis, 40 (40%) had cardiac arrest, and 10 of 47 (21%) children with neuroimaging had acute abnormal findings. Of 50 children eligible for follow-up at 6 or 12 months, 40 (80%) returned for at least one visit. At the follow-up visit of longest interval from ECMO, the median Vineland Adaptive Behavior Scales-II (VABS-II) score was 91 (interquartile range [IQR], 81-98), the median Pediatric Stroke Outcome Measure (PSOM) score was 1 (IQR, 0-2), and the median Mullen Scales of Early Learning composite score was 85 (IQR, 72-96). Presence of new neuroimaging abnormalities during ECMO or within 6 weeks post-ECMO was associated with VABS-II score <85 or death within 12 months after ECMO. The Pediatric Cerebral Performance Category at hospital discharge showed a strong relationship with unfavorable VABS-II and PSOM scores at 6 or 12 months after ECMO. In this study, we report a higher prevalence of pre-ECMO neurologic conditions than previously described. In survivors to hospital discharge, median scores for adaptive behavior and cognitive, neurologic, and quality of life assessments were all below the general population means, but most deficits would be considered minor within each of the domains tested.

Defining outcomes following congenital diaphragmatic hernia using standardised clinical assessment and management plan (SCAMP) methodology within the CDH EURO consortium

Treatment modalities for neonates born with congenital diaphragmatic hernia (CDH) have greatly improved in recent times with a concomitant increase in survival. In 2008, CDH EURO consortium, a collaboration of a large volume of CDH centers in Western Europe, was established with a goal to standardize management and facilitate multicenter research. However, limited knowledge on long-term outcomes restricts the identification of optimal care pathways for CDH survivors in adolescence and adulthood. This review aimed to evaluate the current practice of long-term follow-up within the CDH EURO consortium centers, and to review the literature on long-term outcomes published from 2000 onward. Apart from having disease-specific morbidities, children with CDH are at risk for impaired neurodevelopmental problems and failure of educational attainments which may affect participation in society and the quality of life in later years. Thus, there is every reason to offer them long-term multidisciplinary follow-up programs. We discuss a proposed collaborative project using standardized clinical assessment and management plan (SCAMP) methodology to obtain uniform and standardized follow-up of CDH patients at an international level.

Neurologic Outcomes After Extracorporeal Membrane Oxygenation: A Systematic Review

OBJECTIVES

The goal of this systematic review of the literature was to summarize neurologic outcomes following neonatal and pediatric extracorporeal membrane oxygenation.

DATA SOURCES

We conducted electronic searches of PubMed, Scopus, Web of Science, CINAHL, Cochrane, and EMBASE.

STUDY SELECTION

Inclusion criteria included publication dates 2000-2016, patient ages 0-18 years, and use of standardized measures to evaluate outcomes after extracorporeal membrane oxygenation.

DATA EXTRACTION

We identified 3,497 unique citations; 60 full-text articles were included in the final review.

DATA SYNTHESIS

Studies evaluated patients with congenital diaphragmatic hernia (7), cardiac disease (8), cardiac arrest (13), and mixed populations (32). Follow-up was conducted at hospital discharge in 10 studies (17%) and at a median of 26 months (interquartile range, 8-61 mo) after extracorporeal membrane oxygenation in 50 studies (83%). We found 55 outcome measures that assessed overall health and function (4), global cognitive ability (7), development (4), motor function (5), adaptive function (2), behavior/mood (6), hearing (2), quality of life (2), school achievement (5), speech and language (6), learning and memory (4), and attention and executive function (8). Overall, 10% to as many as 50% of children scored more than 2 SDS below the population mean on cognitive testing. Behavior problems were identified in 16-46% of children tested, and severe motor impairment was reported in 12% of children. Quality of life of former extracorporeal membrane oxygenation patients evaluated at school age or adolescence ranged from similar to healthy peers, to 31-53% having scores more than 1 SD below the population mean.

CONCLUSIONS

This systematic review of the literature suggests that children who have undergone extracorporeal membrane oxygenation suffer from a wide range of disabilities. A meta-analysis was not feasible due to heterogeneity in pathologies, outcome measures, and age at follow-up, underscoring the importance of developing and employing a core set of outcomes measures in future extracorporeal membrane oxygenation studies.

Short-Term Neurodevelopmental Outcome in Congenital Diaphragmatic Hernia: The Impact of Extracorporeal Membrane Oxygenation and Timing of Repair

OBJECTIVES

The purpose of this study was to assess the need and timing of extracorporeal membrane oxygenation in relation to congenital diaphragmatic hernia repair as modifiers of short-term neurodevelopmental outcomes.

DESIGN

Retrospective study.

SETTING

A specialized tertiary care center.

PATIENTS

Between June 2004 and February 2016, a total of 212 congenital diaphragmatic hernia survivors enrolled in our follow-up program. Neurodevelopmental outcome was assessed at a median age of 22 months (range, 5-37) using the Bayley Scales of Infant Development, third edition. Fifty patients (24%) required extracorporeal membrane oxygenation support. Four patients (8%) were repaired prior to cannulation, 25 (50%) were repaired on extracorporeal membrane oxygenation, and 21 (42%) were repaired after decannulation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Children with congenital diaphragmatic hernia, who required extracorporeal membrane oxygenation scored on average 4.6 points lower on cognitive composite (p = 0.031) and 9.2 points lower on the motor composite (p < 0.001). Language scores were similar between groups. Mean scores for children with congenital diaphragmatic hernia repaired on extracorporeal membrane oxygenation were significantly lower for cognition (p = 0.021) and motor (p = 0.0005) outcome. Language scores were also lower, but did not reach significance. A total of 40% of children repaired on extracorporeal membrane oxygenation scored below average in all composites, whereas only 9% of the non-extracorporeal membrane oxygenation, 4% of the repaired post-extracorporeal membrane oxygenation, and 25% of the repaired pre-extracorporeal membrane oxygenation patients scored below average across all domains. Only 20% of congenital diaphragmatic hernia survivors repaired on extracorporeal membrane oxygenation support scored within the average range for all composite domains. Duration of extracorporeal membrane oxygenation support was not associated with a higher likelihood of adverse cognitive (p = 0.641), language (p = 0.147), or motor (p = 0.720) outcome.

CONCLUSIONS

Need for extracorporeal membrane oxygenation in congenital diaphragmatic hernia survivors is associated with worse neurocognitive and neuromotor outcome. Need for congenital diaphragmatic hernia repair while on extracorporeal membrane oxygenation is associated with deficits in multiple domains. Overall time on extracorporeal membrane oxygenation did not impact neurodevelopmental outcome.

Long-term morbidity of congenital diaphragmatic hernia: A plea for standardization

Congenital diaphragmatic hernia (CDH) survivors present long-term morbidities in several systems, including the neurodevelopmental, gastrointestinal, pulmonary, and musculoskeletal ones, and CDH long-term sequelae are increasingly being recognized. Due to high co-morbidity, health related quality of life in a significant proportion of CDH patients might be compromised. As a consequence of consciousness on the long-term sequelae of CDH survivors, and their consequences for life, several follow-up programs were brought to life worldwide. In this review, we will summarize the long-term sequelae of CDH survivors, the impact of new treatments, and analyze the consistency of follow-up programs.

Acute Neonatal Respiratory Failure

Acute respiratory failure requiring assisted ventilation is one of the most common reasons for admission to the neonatal intensive care unit. Respiratory failure is the inability to maintain either normal delivery of oxygen to the tissues or normal removal of carbon dioxide from the tissues. It occurs when there is an imbalance between the respiratory workload and ventilatory strength and endurance. Definitions are somewhat arbitrary but suggested laboratory criteria for respiratory failure include two or more of the following: PaCO₂ > 60 mmHg, PaO₂ < 50 mmHg or O₂ saturation <80 % with an FiO₂ of 1.0 and pH < 7.25 (Wen et al. 2004).

Neurodevelopmental outcome in congenital diaphragmatic hernia: Evaluation, predictors and outcome

To review the reported neurodevelopmental outcome of congenital diaphragmatic hernia (CDH) survivors, identify important predictors of developmental disabilities, and describe the pathophysiological mechanisms contributing to adverse outcome. A Medline search was performed for English-language articles cross-referencing CDH with pertinent search terms. Retrospective, prospective, and longitudinal follow-up studies were examined. The reference lists of identified articles were also searched. Neurodevelopmental dysfunction has been recognized as one of most common and potentially most disabling outcome of CDH. Intelligence appears to be in the low normal to mildly delayed range. Neuromotor dysfunction is common during early childhood. Behavioral problems, hearing impairment, and quality of life related issues are frequently encountered in older children and adolescence. Disease severity correlates with the degree of neurological dysfunction. Neurodevelopmental follow-up in CDH children should become standard of care to identify those who would benefit from early intervention services and improve neurological outcomes.

Sensorineural hearing loss in congenital diaphragmatic hernia survivors is associated with postnatal management and not defect size

BACKGROUND/PURPOSE

We determined the incidence of sensorineural hearing loss (SNHL; >20dB at any frequency) in a contemporary cohort of congenital diaphragmatic hernia (CDH) survivors at a single tertiary care center and identified potential risk factors for SNHL.

METHODS

From 2000 through 2011, clinical and audiologic data were collected on 122 surgically-repaired Bochdalek CDH patients. CDH defect size, duration of ventilation, and cumulative aminoglycoside treatment were used for multivariate logistic regression.

RESULTS

Incidence of SNHL was 7.4% (9/122). We identified one significant independent predictor of SNHL: cumulative length of aminoglycoside treatment (P<.001; OR 1.44, 95% CI: 1.13-1.83).

CONCLUSIONS

Over the last decade, the incidence of SNHL in our CDH patients is low compared to previous reports in the literature (7.4%) and is not associated with CDH defect size or the need for extracorporeal membrane oxygenation. Prolonged duration of aminoglycoside treatment increases the risk of SNHL independent of defect size and duration of ventilation.

Incidence and factors associated with sensorineural and conductive hearing loss among survivors of congenital diaphragmatic hernia

PURPOSE

The reported incidence of sensorineural hearing loss (SNHL) in long-term survivors of congenital diaphragmatic hernia varies widely in the literature. Conductive hearing loss (CHL) is also known to occur in CDH patients, but has been less widely studied. We sought to characterize the incidence and risk factors associated with SNHL and CHL in a large cohort of CDH patients who underwent standardized treatment and follow-up at a single institution.

METHODS

We retrospectively reviewed charts of all CDH patients in our pulmonary hypoplasia program from January 2004 through December 2012. Categorical variables were analyzed by Fisher's exact test and continuous variables by Mann-Whitney t-test (p≤0.05).

RESULTS

A total of 112 patients met study inclusion criteria, with 3 (2.7%) patients diagnosed with SNHL and 38 (34.0%) diagnosed with CHL. SNHL was significantly associated with requirement for ECMO (p=0.0130), prolonged course of hospitalization (p=0.0011), duration of mechanical ventilation (p=0.0046), requirement for tracheostomy (p=0.0013), and duration of loop diuretic (p=0.0005) and aminoglycoside therapy (p=0.0003).

CONCLUSIONS

We have identified hearing anomalies in over 30% of long-term CDH survivors. These findings illustrate the need for routine serial audiologic evaluations throughout childhood for all survivors of CDH and stress the importance of targeted interventions to optimize long-term developmental outcomes pertaining to speech and language.

Longitudinal neurodevelopmental and neuromotor outcome in congenital diaphragmatic hernia patients in the first 3 years of life

OBJECTIVE

The objective of this study was to longitudinally evaluate the neurodevelopmental (ND) outcome in congenital diaphragmatic hernia (CDH) survivors during the first 3 years of life.

STUDY DESIGN

The study cohort consists of 47 CDH survivors that were enrolled in our prospective, follow-up program between July 2004 and September 2010, and underwent serial ND evaluations during the first 3 years of life. ND outcomes were evaluated using the Bayley Scales of Infant Development (BSID)-II or BSID-III. Persistent ND impairment was defined as a score that remained 79 for the cognitive, language and psychomotor domains at the most recent follow-up visit compared with the first assessment.

RESULT

The median age at first and last evaluation was 8 (range, 5 to 15) and 29 (range, 23 to 36) months, respectively. During the follow-up, ND scores improved to average in 17%, remained average in 60%, remained delayed in 10%, improved from severely delayed to mildly delayed in 2% and deteriorated from average to delayed in 15%. Motor scores improved to average in 26%, remained average in 55%, remained delayed in 8% and improved from severely delayed to mildly delayed in 11%. Intrathoracic liver position (P=0.004), preterm delivery (P=0.03), supplemental O2 requirement at day of life 30 (P=0.007), age at discharge (P=0.03), periventricular leukomalacia (PVL; P=0.004) and initial neuromuscular hypotonicity (P=0.01) were associated with persistent motor delays. No relationship was found between patient's characteristics and the risk of persistent cognitive and language delays.

CONCLUSION

(1) The majority of children with CDH are functioning in the average range by early preschool age, (2) most children who had early delays showed improvement in their ND outcome, (3) children showing delays in all the three domains were the least likely to show improvement and (4) CDH severity appears to be predictive of persistent psychomotor delays.

Congenital diaphragmatic hernia

Congenital Diaphragmatic Hernia (CDH) is defined by the presence of an orifice in the diaphragm, more often left and posterolateral that permits the herniation of abdominal contents into the thorax. The lungs are hypoplastic and have abnormal vessels that cause respiratory insufficiency and persistent pulmonary hypertension with high mortality. About one third of cases have cardiovascular malformations and lesser proportions have skeletal, neural, genitourinary, gastrointestinal or other defects. CDH can be a component of Pallister-Killian, Fryns, Ghersoni-Baruch, WAGR, Denys-Drash, Brachman-De Lange, Donnai-Barrow or Wolf-Hirschhorn syndromes. Some chromosomal anomalies involve CDH as well. The incidence is < 5 in 10,000 live-births. The etiology is unknown although clinical, genetic and experimental evidence points to disturbances in the retinoid-signaling pathway during organogenesis. Antenatal diagnosis is often made and this allows prenatal management (open correction of the hernia in the past and reversible fetoscopic tracheal obstruction nowadays) that may be indicated in cases with severe lung hypoplasia and grim prognosis. Treatment after birth requires all the refinements of critical care including extracorporeal membrane oxygenation prior to surgical correction. The best hospital series report 80% survival but it remains around 50% in population-based studies. Chronic respiratory tract disease, neurodevelopmental problems, neurosensorial hearing loss and gastroesophageal reflux are common problems in survivors. Much more research on several aspects of this severe condition is warranted.

Bilateral sensory permanent hearing loss after palliative hypoplastic left heart syndrome operation

BACKGROUND

Bilateral sensory permanent hearing loss (PHL) has been reported after neonatal respiratory failure but has rarely been noted in survivors after cardiac operations. We report the prevalence and severity of PHL after Norwood right ventricular-pulmonary artery shunt for hypoplastic left heart syndrome (HLHS), document progressive loss, and explore markers of acute illness and ototoxic medications for PHL.

METHODS

This interprovincial longitudinal outcome study after neonatal complex cardiac operations at Stollery Children's Hospital, Edmonton, Alberta, Canada, 2002 to 2007, completed repeated diagnostic audiologic assessments for all survivors by registered pediatric-experienced audiologists. Demographic, surgical, and perisurgical variables, including ototoxic medications, were collected. The association of potentially predictive variables with PHL and its severity were determined by univariate analysis and multiple logistic and linear regression analysis.

RESULTS

At an age older than 3.5 years, progressive PHL was present in 12 of 42 survivors (28.6%, 95% confidence interval, 16.2% to 44.8%; mortality, 20.9%). Overall lowest partial pressure of arterial oxygen (odds ratio, 1.315; 95% confidence interval, 1.051 to 1.506), and cumulative dose of furosemide given as bolus (odds ratio, 1.062; 95% confidence interval, 1.018 to 1.109) combined to predict PHL and gave 39% of the variance of PHL severity. Antibiotics and neuromuscular blockers were not associated with PHL.

CONCLUSIONS

Monitoring outcomes of neonates after HLHS surgery revealed unexpected PHL associated with hypoxia and bolus administration of furosemide. As survival improves, close follow-up is necessary to identify outcomes and seek modifiable predictive variables. Changes in the mode of furosemide administration may prevent this complication.

Developmental outcomes following major surgery: what does the literature say?

Relative to the wealth of information in the medical literature regarding developmental outcome for infants who have had cardiac surgery available, few studies specifically detail how those who have undergone major surgery grow and develop. The few published studies tend to be disease specific, making their results difficult to translate to a more general setting. As mortality for most infants who require surgery in infancy continues to decrease, the focus for researchers and clinicians should be on how these children will grow and develop. As parents realise that their infant will survive, this becomes their next major concern. The most common conditions requiring early major surgery have been reviewed in relation to data on infant developmental outcomes.

Neurodevelopmental and neurofunctional outcomes in children with congenital diaphragmatic hernia

The objective of this review was to provide a critical overview of our current understanding on the neurocognitive, neuromotor, and neurobehavioral development in congenital diaphragmatic hernia (CDH) patients, focusing on three interrelated clinical issues: (1) comprehensive outcome studies, (2) characterization of important predictors of adverse outcome, and (3) the pathophysiological mechanism contributing to neurodevelopmental disabilities in infants with CDH. Improved survival for CDH has led to an increasing focus on longer-term outcomes. Neurodevelopmental dysfunction has been recognized as the most common and potentially most disabling outcome of CDH and its treatment. While increased neuromotor dysfunction is a common problem during infancy, behavioral problems, hearing impairment and quality of life related issues are frequently found in older children and adolescence. Intelligence appears to be in the low normal range. Patient and disease specific predictors of adverse neurodevelopmental outcome have been defined. Imaging studies have revealed a high incidence of structural brain abnormalities. An improved understanding of the pathophysiological pathways and the neurodevelopmental consequences will allow earlier and possibly more targeted therapeutic interventions. Continuous assessment and follow-up as provided by an interdisciplinary team of medical, surgical and developmental specialists should become standard of care for all CDH children to identify and treat morbidities before additional disabilities evolve and to reduce adverse outcomes.

Mortality in infants with congenital diaphragmatic hernia: a study of the United States National Database

OBJECTIVE

To examine the effect of regionalization of care on outcomes of neonates with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

We analyzed the National Inpatient Sample and the 'Kids' database for the years 1997 to 2004. Infants with CDH were grouped based on whether they underwent surgical repair at the hospital of birth, or at another facility. Groups were compared using chi-square, t-test and logistic regression.

RESULT

A total of 2140 infants were included: 41% were females, 42% were Caucasians, 48% were transported, 20% reported the use of extracorporeal membrane oxygenation (ECMO)and 33% died. Only 79% underwent operative repair, in which 85% survived after surgery. Survival among operated patients who used ECMO was 40%. Transported infants used more ECMO than non-transported ones (25 vs 15%; adjusted odds ratio (OR) 1.46; confidence interval 1.1 to 1.9, P=0.007), and had higher mortality after surgery (16 vs 13%; adjusted OR 1.46; confidence interval 1.1 to 2, P=0.02).

CONCLUSION

The utilization of neonatal transport of CDH patients is associated with increased mortality and increased need for ECMO. This study supports the need for regionalization of care, and favors maternal transport before delivery of CDH newborns.

CONTEMPORARY NEONATAL INTENSIVE CARE MANAGEMENT IN CONGENITAL DIAPHRAGMATIC HERNIA: DOES THIS OBVIATE THE NEED FOR FETAL THERAPY?

The management of congenital diaphragmatic hernia (CDH) in the newborn infant has changed radically since the first successful outcomes were reported 60 years ago. Then it seemed a surgical problem with a surgical solution – do an operation, remove the intestines and solid viscera from the thoracic cavity, repair the defect and allow the lung to expand. CDH in that era was regarded as the quintessential neonatal surgical emergency. The expectation was that urgent surgery would result in improvement in lung function and oxygenation. That approach persisted up to the 1980s when it was realized that the problem was far more complex and involved both an abnormal pulmonary vascular bed as well as pulmonary hypoplasia. The use of systemically delivered pulmonary vasodilator therapy, principally tolazoline, became a focus of interest in the 1980s with small case reports and case series suggesting improved survival. In the 1990s, based on studies that showed worsening thoracic compliance and gas exchange following surgical repair, deferred surgery and pre-operative stabilization became the standard of care. At the same time extracorporeal membrane oxygenation (ECMO) was increasingly used either as part of pre-operative stabilization or as a rescue therapy after repair. Other centres chose to use high frequency oscillatory ventilation (HFOV). Despite all these innovations the survival in live born infants with CDH did not improve to more than 50% in large series published from high volume centres. However, in the past 10 years there has been an appreciable improvement in survival to the extent that many centres are now reporting survival rates of greater than 80%. Probably the biggest impact on this improvement has been the recognition of the role that ventilation induced lung injury plays in mortality and the need for ECMO rescue. This has ushered in an era of a lung protective or “gentle ventilation” strategy which has been widely adopted as a standard approach. While there have been these radical changes in postnatal management attempts have been made to improve outcome with prenatal interventions, starting with prenatal repair, which was abandoned because of preterm labour. More recently there has been increasing experience in the use of balloon occlusion of the trachea as a prenatal intervention strategy with patients being selected based on prenatal predictors of poor outcome. This approach can only be justified if those predictors can be validated and the outcomes (death or serious long term morbidity) can be shown to be better than those currently achievable, namely 80% survival in high volume CDH centres rather than the 50–60% survival frequently quoted in historical papers.

Extracorporeal Membrane Oxygenation for the Treatment of Neonatal Respiratory Failure

This review discusses the use of extracorporeal membrane oxygenation (ECMO) for the treatment of respiratory failure in neonates. After briefly reviewing the early history of neonatal ECMO, the authors describe the respiratory diagnoses most often treated with ECMO and the manner in which affected neonates are deemed to have “failed” conventional therapies and thus require ECMO. After reviewing the most common indications for ECMO, factors that influence the timing of conversion to extracorporeal life support, as well as criteria that may exclude patients from receiving ECMO therapy, are described. At the conclusion of this article, the authors discuss the long-term outcomes of neonates whose respiratory disease was treated with ECMO and the costs associated with that care.

Congenital diaphragmatic hernia: current status and review of the literature

Treatment of congenital diaphragmatic hernia (CDH) challenges obstetricians, pediatric surgeons, and neonatologists. Persistent pulmonary hypertension (PPHT) associated with lung hypoplasia in CDH leads to a high mortality rate at birth. PPHT is principally due to an increased muscularization of the arterioles. Management of CDH has been greatly improved by the introduction of prenatal surgical intervention with tracheal obstruction (TO) and by more appropriate postnatal care. TO appears to accelerate fetal lung growth and to increase the number of capillary vessels and alveoli. Improvement of postnatal care over the last years is mainly due to the avoidance of lung injury by applying low peak inflation pressure during ventilation. The benefits of other drugs or technical improvements such as the use of inhaled nitric oxide or extracorporeal membrane oxygenation (ECMO) are still being debated and no single strategy is accepted worldwide. Despite intensive clinical and experimental research, the treatment of newborn with CDH remains difficult.

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.

Neurodevelopmental outcomes of congenital diaphragmatic hernia survivors followed in a multidisciplinary clinic at ages 1 and 3

PURPOSE

Infants who survive congenital diaphragmatic hernia (CDH) repair may have ongoing medical and neurodevelopmental morbidity after hospital discharge. We evaluated the relationship between medical and neurodevelopmental outcomes of CDH survivors seen in a multidisciplinary clinic at ages 1 and/or 3.

METHODS

From January 1997 to December 2004, 69 (61%) of 112 CDH survivors were followed in our CDH clinic at ages 1 and/or 3. Medical issues (cardiac, pulmonary, gastrointestinal) were tabulated at hospital discharge and at follow-up. Neurodevelopmental data were obtained from clinic assessments by a neurodevelopmental pediatrician. Descriptive results were summarized for each cohort. Multivariate analyses were performed to identify predictors of motor problems at age 1.

RESULTS

Of the 69 study participants, 64% were male, 75% had left-sided CDH, 17% had cardiac anomalies, and 25% had other congenital malformations. Nearly all required ventilator management (99%) with a median ventilator time of 14 days (range, 1-54 days); 30% required extracorporeal membrane oxygenation. While 87% of patients had medical issues at hospital discharge, 61% and 67% had medical issues at ages 1 and 3, respectively. Pulmonary problems were noted in 34% and 33% of the ages 1 and 3 cohorts, respectively. Motor and language problems were detected in 60% and 18% of the age 1 cohort and 73% and 60% of the age 3 cohort, respectively. Multivariate analysis found ventilator time as the only independent predictor of motor problems at age 1 (odds ratio, 1.12 per day; 95% confidence interval, 1.05-1.20; P < .01).

CONCLUSIONS

Young CDH survivors continue to have ongoing medical problems and a high incidence of motor and language problems. Duration of neonatal ventilatory support was a significant predictor of motor problems at age 1. Prospective studies are needed to confirm these findings.

Postdischarge follow-up of infants with congenital diaphragmatic hernia

Infants with congenital diaphragmatic hernia often require intensive treatment after birth, have prolonged hospitalizations, and have other congenital anomalies. After discharge from the hospital, they may have long-term sequelae such as respiratory insufficiency, gastroesophageal reflux, poor growth, neurodevelopmental delay, behavior problems, hearing loss, hernia recurrence, and orthopedic deformities. Structured follow-up for these patients facilitates early recognition and treatment of these complications. In this report, follow-up of infants with congenital diaphragmatic hernia is outlined.

Risk factors for sensorineural hearing loss in survivors with severe congenital diaphragmatic hernia

Recent improvements in perinatal management have improved the prognosis in patients with severe congenital diaphragmatic hernia (CDH). However, in surviving patients with severe CDH, hearing loss has sometimes been reported to occur during the follow-up period. Although some of the risk factors for developing sensorineural hearing loss (SNHL) have been reported in CDH, no definitive risk factors have yet been reported. We, therefore, investigated the risk factors regarding postnatal management in patients with severe CDH. In 16 surviving patients with severe CDH, which had all been detected antenatally, and whose lung-to-thoracic ratio was less than 0.2, four patients demonstrated late onset SNHL, which occurred between 1.5 and 5 years of age. The risk factors for SNHL regarding the postnatal treatment for CDH were analyzed between the four patients with SNHL and the remaining 12 patients without SNHL, regarding such factors as the use of ototoxic drugs, neuromuscular blocking agents, high-frequency oscillation (HFO), and inhaled nitric oxide, the duration of hypocapnia, hypoxia, severe acidosis, severe alkalosis, and mechanical ventilation. In addition, the types of neuromuscular blocking agents were also analyzed, including the administration of pancuronium bromide (PB) and vecuronium bromide (VB). The patients with SNHL were found to have a significantly higher risk than the patients without SNHL regarding the duration of loop diuretics usage and the duration of usage of both mechanical ventilation and HFO. Furthermore, all four patients with SNHL used PB. In contrast, none of the five patients using VB developed SNHL The duration and cumulative dose of PB used in the patients with severe CDH showed a significant correlation to the occurrence of SNHL. Although this study was retrospective, based on our data, the prolonged use of PB, in addition to the duration of treatment by loop diuretics, mechanical ventilation, and HFO usage, might, thus, be suggested to be a possible risk factor for late onset SNHL in patients with severe CDH.

Long-term follow up of infants with congenital diaphragmatic hernia

With improving treatment strategies for congenital diaphragmatic hernia (CDH) infants, an increase in survival of more severely affected patients can be expected. Consequently, more attention is now focused on long-term follow up of these patients. Many reports have emphasized associated morbidity, including pulmonary sequelae, neurodevelopmental deficits, gastrointestinal disorders, and other abnormalities. Therefore, survivors of CDH remain a complex patient population to care for throughout infancy and childhood, thus requiring long-term follow up. Much information has been provided from many centers regarding individual institutional improvements in overall survival. Few of these, however, have reported long-term follow up. The aim of this review is to describe the long-term outcome of survivors with CDH and to suggest a possible follow-up protocol for these patients.

Long-term functional impact of congenital diaphragmatic hernia repair on children

BACKGROUND/PURPOSE

Congenital diaphragmatic hernia (CDH) is a malformation requiring neonatal surgical repair with in-hospital survival rates above 90%. We examined the long-term functional impact of CDH repair on a cross-sectional cohort of survivors.

METHODS

A cohort of 53 CDH families participated in this study. Functional impact was evaluated with parent report of the Functional Status IIR and the Child Health Ratings Inventories General Health Module. Parents also provided a clinical severity score, the child's medical history, and family demographic information. The primary outcome was the effect of medical morbidity on the Functional Status IIR total score.

RESULTS

Congenital diaphragmatic hernia survivors had a median age of 8 years; 50% were in third grade or above. Sixty-six percent had major medical issues at hospital discharge, whereas 48% had current clinical problems. Functional Status IIR total score was strongly correlated with child's clinical severity (r = -0.65; P < .0001) and was lower among children with ongoing medical morbidity, denoting worse functioning (P = .01). Child Health Ratings Inventories General Health Module scores followed a similar pattern.

CONCLUSIONS

A subset of long-term CDH survivors continues to have ongoing clinical problems a median of 8 years after surgery, translating to lower functional status. Affected children and their families may benefit from prospective identification and ongoing interventions.

Neurodevelopmental outcomes and surgery in neonates

A neonate requiring major surgery in 2006 has a greater prospect of survival than ever before. Increasingly, however, there is awareness that critical illness may affect later neurodevelopment. Pre-existing conditions in addition to the physiologic stresses associated with cardiac and general surgery are implicated but remain unavoidable in the case of significant structural abnormalities such as transposition of the great arteries or congenital diaphragmatic hernia. For those affected by neurodevelopmental impairment, there is a significant cost to the child, family and society. Current research focuses on the preventable causes of brain injury, before, during and after the intervention, and the rate of impairment in apparently uncomplicated procedures. In contrast to the quantity of neurodevelopmental outcome data following cardiac surgery, there remain few outcome studies dealing with non-cardiac surgery despite such intervention being two to three times more common. There appear to be compelling clinical and economic arguments for the instigation of formalised population-based developmental assessments for all infants undergoing major surgery.

The price of success in the management of congenital diaphragmatic hernia: is improved survival accompanied by an increase in long-term morbidity?

BACKGROUND

The impact of "gentle ventilation" (GV) strategies on morbidity and mortality of patients with congenital diaphragmatic hernia (CDH) in our institution has not been determined. This study reviews the primary and secondary outcomes of our patients with CDH treated with the GV approach.

METHOD

We performed a retrospective chart review of respiratory, neurologic, nutritional, and musculoskeletal morbidities in patients with CDH treated at a single institution between 1985 and 1989 with conventional ventilation (CV) compared with those treated from 1996 to 2000 with GV.

RESULTS

There were 77 CV-treated and 66 GV-treated patients with CDH, with 51% survival in the CV cohort compared with 80% in the GV group (chi(2), P < .05). At 3-year follow-up, we found no statistically significant differences in the frequency of respiratory (38% of CV patients, 50% of GV patients), neurologic (29% of CV patients, 34% of GV patients), or musculoskeletal morbidity (46% of CV vs 29% of GV-treated patients). There was a difference in nutritional morbidity as indicated by the increased frequency of gastrostomy tube use in the GV-treated patients (34%) compared with the CV patients (8%; chi2, P < .05).

CONCLUSION

The implementation of GV techniques has significantly decreased mortality in infants with CDH. This has been associated with a documented increase in nutritional morbidity among survivors.

The immediate and long-term outcomes of newborns with congenital diaphragmatic hernia

In spite of the innovations in the management of newborns with congenital diaphragmatic hernia (CDH) presenting with respiratory distress at birth, mortality and ongoing morbidity still remain high. This is a retrospective analysis of newborns with CDH to determine the immediate and long-term outcomes among survivors. Medical records of newborns with CDH and respiratory distress at birth between January 1993 and March 2002 were reviewed retrospectively. There were 45 newborns, 29 males and 16 females. Eleven newborns (24%) died during the period of preoperative stabilization, 9 from pulmonary hypoplasia and 2 with complex anomalies who were not resuscitated. Surgery was performed in 34 newborns (76%). Three died postoperatively from severe pulmonary hypoplasia and pulmonary hypertension. Eleven newborns (24%) had sepsis from coagulative-negative staphylococci. Thirty-one of 43 newborns (72%) with isolated CDH were discharged home. Twenty-seven of 31 survivors (87%) had adverse long-term outcome and 2 late deaths were from pulmonary complications. Twenty-nine of 43 newborns (67%) with isolated CDH survived. The principal determinant of survival was pulmonary hypoplasia. Eighty-seven percent of survivors have associated morbidity including ongoing pulmonary, nutritional and neuro-developmental problems. Nevertheless preoperative stabilization and delayed surgery have been a satisfactory mode of management.

Ototoxic drugs and sensorineural hearing loss following severe neonatal respiratory failure

AIM

To determine relationships between ototoxic drugs and 4-y sensorineural hearing loss (SNHL) in near-term and term survivors of severe neonatal respiratory failure.

METHODS

All 81 survivors of the Canadian arm of the Neonatal Inhaled Nitric Oxide Study (mortality 32, loss to follow-up 9) received loop diuretics, aminoglycosides, and neuromuscular blockers (NMB), and 50 received vancomycin as neonates. Prospective, longitudinal secondary outcome using audiological tests diagnosed late-onset, progressive SNHL in 43 (53%); not flat (sloping) in 29, flat (severe to profound) in 14. Risk for SNHL was determined.

RESULTS

A combination of duration of diuretic use of >14 d and average NMB dose of >0.96 mg/kg/d contributed to SNHL among survivors (odds ratio 5.2; 95% CI 1.6, 16.7). Markers of illness severity did not contribute. Dosage or duration of aminoglycosides use did not relate to SNHL. Cumulative dosages and duration of use of diuretics; NMB; use of vancomycin; and overlap of diuretics with NMB, aminoglycosides, and vancomycin individually linked to SNHL (p<0.001).

CONCLUSION

Overuse of loop diuretics and/or NMB contributes to SNHL after neonatal respiratory failure; markers of illness severity or the appropriate administration of aminoglycosides do not.

Fog2 is required for normal diaphragm and lung development in mice and humans

Congenital diaphragmatic hernia and other congenital diaphragmatic defects are associated with significant mortality and morbidity in neonates; however, the molecular basis of these developmental anomalies is unknown. In an analysis of E18.5 embryos derived from mice treated with N-ethyl-N-nitrosourea, we identified a mutation that causes pulmonary hypoplasia and abnormal diaphragmatic development. Fog2 (Zfpm2) maps within the recombinant interval carrying the N-ethyl-N-nitrosourea-induced mutation, and DNA sequencing of Fog2 identified a mutation in a splice donor site that generates an abnormal transcript encoding a truncated protein. Human autopsy cases with diaphragmatic defect and pulmonary hypoplasia were evaluated for mutations in FOG2. Sequence analysis revealed a de novo mutation resulting in a premature stop codon in a child who died on the first day of life secondary to severe bilateral pulmonary hypoplasia and an abnormally muscularized diaphragm. Using a phenotype-driven approach, we have established that Fog2 is required for normal diaphragm and lung development, a role that has not been previously appreciated. FOG2 is the first gene implicated in the pathogenesis of nonsyndromic human congenital diaphragmatic defects, and its necessity for pulmonary development validates the hypothesis that neonates with congenital diaphragmatic hernia may also have primary pulmonary developmental abnormalities.

Factors associated with sensorineural hearing loss among survivors of extracorporeal membrane oxygenation therapy

OBJECTIVES

To endeavor to explain why some graduates of extracorporeal membrane oxygenation (ECMO) therapy develop sensorineural hearing loss (SNHL) whereas others do not, to study the variability seen in the degree of SNHL, to attempt to explain why some graduates with SNHL experience progressive worsening whereas others do not, and to describe the time course of the onset of SNHL on the basis of identified risk factors.

DESIGN

A retrospective chart review with proportional-hazards regression analysis to identify specific risk factors for SNHL from a list of patient and treatment variables.

SETTING

Children's Hospital Boston, a pediatric tertiary-care facility and ECMO center.

PATIENTS

Neonatal ECMO graduates born in 1986-1994 who survived to discharge and underwent audiologic evaluations (n = 111) and a random sample of ECMO graduates who survived to discharge and did not undergo audiologic evaluations (n = 30).

OUTCOME MEASURES

Audiologic data, including the presence or absence of SNHL, the severity of SNHL at the most recent evaluation, the stability or progressive worsening of hearing (with the first evaluation compared with the most recent evaluation), and the occurrence of delayed-onset SNHL.

RESULTS

Twenty-nine (26%) of 111 ECMO graduates who underwent audiologic testing had SNHL at the last evaluation. Of these 29 subjects with SNHL, 21 (72%) had progressive SNHL, of whom 14 (48%) had delayed-onset SNHL. The age of identification of SNHL ranged from 4 months to 8 years 11 months. Factors identified with proportional-hazards regression analyses as being associated significantly with the time to onset of SNHL were a primary diagnosis of congenital diaphragmatic hernia (hazard ratio: 2.60), length of ECMO therapy (hazard ratio: 7.18), and number of days children received aminoglycoside antibiotics (hazard ratio: 5.56). Kaplan-Meier "time-to-event" curves were constructed to illustrate the time course of onset of SNHL, as affected by each of the variables identified as significant risk factors.

CONCLUSIONS

These findings illustrate the need for early, routine, audiologic evaluations throughout childhood for all ECMO graduates. Children at even greater risk for developing SNHL because of a history of congenital diaphragmatic hernia, prolonged ECMO therapy, and/or a lengthy course of aminoglycoside antibiotic therapy should be monitored even more closely throughout childhood, depending on the child's individual risk indicators, as suggested here. On the basis of these risk indicators, efforts can be made to minimize the risk of hearing loss while a child is being treated with ECMO. In addition, these risk indicators can assist with counseling families of ECMO graduates regarding the child's specific risk of developing SNHL and how it can be managed should it occur.

Follow up of infants with congenital diaphragmatic hernia

Survival of patients with congenital diaphragmatic hernia has improved with the introduction of more sophisticated treatments. Long-term follow up has led to the recognition of pulmonary morbidity not previously recognized. In addition, extrapulmonary problems associated with the survival of these high-risk infants are now being identified. This review describes associated morbidities in congenital diaphragmatic hernia survivors and their predictors.

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.

Medical management of childhood hearing loss

Hearing loss in children is common. Advances in the identification of infectious diseases at birth or in utero, genetic testing, and diagnostic imaging now permit many infants and children to be identified and treated sooner. Treatment and rehabilitation should be instituted early so that the effects of hearing loss on communication are minimized and the child's social and academic skills maximized. CHL can usually be managed medically or surgically with subsequent return to normal or near normal hearing. Children with SNHL, and their future hearing will benefit from new antiviral agents, less antibiotics, ototoxic more focused chemotherapy, and possibly genetic therapy. Digital and programmable hearing aids, more accessible FM systems, cochlear implants, and bone-anchored hearing aids provide significant rehabilitation potential for children with even very significant hearing losses. Early identification and prevention, however, remain the best strategies to combat hearing loss in children.

The CDH Study Group and advances in the clinical care of the patient with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) occurs in 1 of every 2000 to 4000 births and accounts for 8% of all major congenital anomalies. Recurrence risk for a subsequent pregnancy is estimated at 2%. The mortality rate for CDH when diagnosed antenatally, varies with fetal age and with the presence or absence of hydramnios and degree of pulmonary hypoplasia. The prognosis has improved dramatically in recent years, primarily due to advances in neonatal and surgical interventions. Neonatal survival rates with an antenatal diagnosis now exceed 80% in some centers. Treatment for infants with CDH reflects other pediatric surgical problems in that a majority of the clinical research that shapes treatment is retrospective in nature. Because CDH is a relatively rare disease, using a compilation of cases, such as the CDH database provides, greatly aids our understanding of this disease process. Moreover, the application of a quality assessment scale provides the practitioner with a knowledge base to critically evaluate the published retrospective data.

Impact of a current treatment protocol on outcome of high-risk congenital diaphragmatic hernia

BACKGROUND

There is considerable debate regarding the optimal management of congenital diaphragmatic hernia (CDH) in high-risk infants (those cases presenting with respiratory distress within 2 hours of birth or those diagnosed prenatally). The aim of this study was to analyze patient outcomes using a new treatment protocol for CDH in a tertiary care non-extracorporeal membrane oxygenation (ECMO) neonatal unit.

METHODS

The records of 78 consecutive neonates with CDH presenting to Bambino Gesù Children's Hospital from 1996 to 2001 were analyzed retrospectively. Of these infants, 70 high-risk patients were identified (prenatal diagnosis or respiratory distress requiring intubation and assisted ventilation within 2 hours after birth), regardless of associated anomalies, medical condition on presentation, or degree of pulmonary hypoplasia. A prenatal diagnosis was made in 46 of 70 (66%) patients. Associated lethal malformations were present in 6 of the children (8.5%). The patients were placed in 3 historical groups: group 1, 19 patients from 1996 to 1997, group 2, 22 patients from 1998 to 1999, and group 3, 29 patients from 2000 to 2001. In the first 2 groups, a new protocol was introduced using inhaled nitric oxide (iNO) and high-frequency oxygen ventilation (HFOV). In the third group, gentle ventilation and permissive hypercarbia were also used routinely. Mortality and severe morbidity--defined as O2 requirement at discharge, need for a tracheostomy, neurologic impairment, or bilateral hearing loss-were evaluated when the patients were at 6 months old. Univariate analysis was performed.

RESULTS

The 3 groups were comparable with respect to predictive risk factors such as side of hernia, prenatal diagnosis, polyhydramnios, stomach and liver in the thorax, associated lethal malformations, and patch. Overall survival rate significantly increased from 47% (9 of 19) in group 1 and 50% (11 of 22) in group 2 to 90% (26 of 29) in group 3 (P =.02). None of the 19 patients in group 1 had severe morbidity compared with 2 of 22 (9%) patients in group 2 and 2 of 29 (7%) patients in group 3. Hearing loss was observed in 4 patients. Mortality rate and preoperative pneumothorax significantly decreased in group 3 compared with groups 1 and 2 (P =.03 and P =.00, respectively).

CONCLUSIONS

(1) The application of new treatment protocol for CDH, using gentle ventilation and permissive hypercarbia, produced a significant increase in survival with concomitant decrease in morbidity. (2) The rate of pneumothorax was significantly decreased by the introduction of permissive hypercarbia and gentle ventilation. (3) As more infants survive CDH without the use of ECMO, severe long-term sequelae of CDH can be recognized in these children.

Current therapy of infants with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a life-threatening anomaly with a significant mortality rate. Despite widespread prenatal diagnosis, few parameters have been well defined to aid in prediction of outcome of these infants. Antenatal maternal steroid administration and foetal surgery are not proven interventions. Postnatal treatment has changed over the last 10 years, with avoidance of hyperventilation and ventilator-induced lung injury resulting in improved survival. Therapies such as inhaled nitric oxide, exogenous surfactant administration and extracorporeal membrane oxygenation (ECMO) have undergone limited study, but show no clear benefit in this population. With improved outcome, principally due to avoidance of barotrauma, greater opportunity exists for long-term evaluation of survivors. To date, continuing problems with pulmonary function, nutrition and growth, effects of right ventricular hypertension and developmental issues have been identified. Through co-ordinated, multidisciplinary evaluation of CDH survivors, improved long-term outcome for these challenging patients can be attained.

Twenty Years of Progress in Congenital Diaphragmatic Hernia at the University of Florida

Over the past 20 years the clinical paradigms underlying the care of children with congenital diaphragmatic hernia (CDH) have undergone profound changes. The purpose of this work is to provide an historic review of research and clinical studies related to CDH at the University of Florida (UF) and Shands Children's Hospital during the chairmanship of Edward M. Copeland, III, M.D. and to present our current clinical results. During Dr Copeland's tenure survival for newborns symptomatic with CDH treated at UF/Shands Children's Hospital has improved from less than 20 per cent to 85 per cent. Clinical observations have suggested and research studies at UF using a fetal lamb model have confirmed that fetal distress can occur late in gestation, which may predispose infants with CDH to pulmonary hypertension. However, our patient experience has confirmed that the most significant cause of mortality in human infants is not pulmonary hypertension but iatrogenic injury to their hypoplastic lungs. Strict avoidance of barotrauma in these babies has been the most important clinical advance during these two decades. Significant clinical and research problems remain including defining optimal prenatal care, management of complications during the first few weeks of life, and development of strategies to accelerate lung growth. Dramatic improvements in survival have resulted in children who manifest a number of clinical problems that were not evident when most of these patients died early in infancy. Our experience at Shand's Children's Hospital/UF indicates that feeding problems, respiratory infections, and management of subtle or overt neurologic complications may become major issues for some of these survivors and their families.

Outcome at 2 years of infants with congenital diaphragmatic hernia: a population-based study

BACKGROUND

Management of neonates with congenital diaphragmatic hernia (CDH) has undergone many changes associated with increased survival of high-risk CDH. However, little is known about the long-term outcome of CDH infants.

METHODS

Follow-up was performed in 85 newborn infants with CDH admitted in our neonatal intensive care unit between January 1991 and December 1998. Early (< 2 months) and late mortality (> or = 2 months), and respiratory, nutritional, musculoskeletal, and neurosensory outcome at 2 years were recorded.

RESULTS

Surgical repair was performed in 59 infants (69%) at a median postnatal age of 124 (range, 38 to 246) hours. Extracorporeal membrane oxygenation was used in 26 (30%) newborn infants. Survival at 2 years was 51 of 85 (60%) (early death, 28/85 [33%]; late death, 6/85 [7%]). Late deaths occurred because of persistent pulmonary hypertension or iatrogenic complications. Twelve of 51 (24%) newborn infants were oxygen dependant at the postnatal age of 28 days, and 1 of 51 (1.9%) was still oxygen dependant at 2 years. Growth failure was noted in 9 of 51 (18%), mainly related to severe gastroesophageal reflux and oral aversion. Scoliosis was diagnosed in 2 infants. Neurologic examination at 2 years was normal in 45 of 51 (88%). Cerebral palsy and developmental delay were observed in 2 and 4 infants, respectively. Four infants (8%) experienced associated problems. Respiratory, nutritional, and musculoskeletal morbidity was higher in infants treated by extracorporeal membrane oxygenation (p < 0.05).

CONCLUSIONS

CDH infants are at risk for adverse nutritional and respiratory outcome. Despite severe respiratory failure at birth, prolonged oxygen therapy above 2 years of age is uncommon. Conversely, failure to thrive related at least in part to gastroesophageal reflux and oral dysfunction remains the major problem at 2 years of age. However, both nutritional and respiratory problems tend to improve with age.

Support of respiratory failure in the pediatric surgical patient

Severe respiratory failure in newborn and pediatric patients is associated with significant morbidity and mortality. Basic science laboratory investigation has led to advances in the understanding of ventilator-induced lung injury and in optimizing the supportive use of conventional ventilation strategies. Over the past few years, progress has been made in alternative therapies for supporting children and adults with severe respiratory failure. This review will focus on recent laboratory and clinical data regarding the techniques of lung protective ventilator strategies, inhaled nitric oxide, liquid ventilation, and extracorporeal life support (ECLS, ECMO). Some of these modalities are commonplace, while others may have much to offer the pediatric clinician if their benefit is clearly demonstrated in future clinical trials.

Congenital diaphragmatic hernia

Congenital diaphragmatic hernia occurs in approximately 1 in every 2500 live births and is associated with a reported mortality of almost 35% in live-born patients and a higher mortality when in utero deaths are counted. Ventilator-induced lung injury, pulmonary hypoplasia, and other associated anomalies account for the high death rate. Numerous adjunctive measures have been used to treat these patients. Inhaled vasodilators (nitric oxide), intravenous vasodilators, and fetal therapy have no proven benefit. While animal models of congenital diaphragmatic hernia are surfactant deficient, controversy remains over the use of surfactant in infants. There has been no clinical trial showing any clear benefit with the use of exogenous surfactant in these patients. Similarly, prenatal corticosteroids show some improvements in animal models, but again, there is a complete absence of supportive data to show benefit in humans. Mechanical ventilator strategies that limit ventilator-induced lung injury by avoiding hyperventilation and lung over inflation are the strategies currently in use that have been associated with improved survival. Long-term follow-up of these patients is quite important since gastroesophageal reflux, developmental delay, chronic lung disease, and chest wall deformity are all seen with increased frequency in these children.

Late-onset, progressive sensorineural hearing loss after severe neonatal respiratory failure

OBJECTIVES

To determine the prevalence of sensorineural hearing loss (SNHL) at the age of 4 years among survivors of severe neonatal respiratory failure with and without congenital diaphragmatic hernia and to document the occurrence of late-onset or progressive SNHL among the survivors.

DESIGN

Prospective, longitudinal secondary outcome study.

SETTING

Multicenter Canadian study in 9 tertiary referral centers.

PATIENTS

Eighty-one (89%) of ninety 4-year-old survivors born from 1994 to 1996 of > or =34 weeks gestation at birth with severe neonatal respiratory failure (2 oxygenation indices > or =25 at least 15 minutes apart).

MAIN OUTCOME MEASURES

Repeated audiologic measurements from birth to the age of 4 years with documentation of the entire cohort at 2 and 4 years of age.

RESULTS

Forty-three (53%) of 81 tested 4-year-old survivors had SNHL; 28 (42%) of 66 without congenital diaphragmatic hernia and 15 (100%) of 15 with congenital diaphragmatic hernia. High-frequency SNHL occurred in 65% of the patients. Of the 43 children with SNHL at 4 years, 30 (70%) had loss at 2 years, and 18 (60%) of these 30 had progressive loss between 2 and 4 years of age. For 13 children with SNHL onset after 2 years of age, the loss was less severe with lesser involvement of the lower frequencies.

CONCLUSION

Survivors of severe neonatal respiratory failure frequently develop late-onset SNHL that may be progressive. Urgent investigation is required to enable further understanding and prevention of this problem. Severe neonatal respiratory failure should be an indication for long-term audiologic surveillance.