Long-term pulmonary sequelae in survivors of congenital diaphragmatic defects

Disease severity impacts perceived quality of life in congenital diaphragmatic hernia: a prospective observational study

BACKGROUND

While research indicates comparable quality of life (QOL) in congenital diaphragmatic hernia (CDH) and healthy populations, the effect of CDH severity on patients' health perceptions remains unexplored. We aimed to assess QOL perception in CDH, hypothesising a decline correlated with increased disease severity.

METHODS

In this prospective observational study, we analysed patients with CDH aged 5 years and above participating in a longitudinal outpatient programme. We excluded bilateral CDH, genetic/syndromic conditions, prematurity and late diagnosis. Participants self-administered the age-adapted Pediatric Quality of Life Inventory (PedsQL) survey, covering four domains (physical, emotional, social, school). After enrolment, data were collected blind to severity status (larger defects denoting significant/'severe' disease). Repeated measurements were managed using a random mixed-effects model.

RESULTS

Of 34 participants (50% males) who completed the PedsQL, 10 provided measurements at two visits. Eight required a patch (type C), while 26 had primary repairs (type A=8; type B=18). Age at first evaluation was comparable across groups (no patch: median 11 (7-16), patch: 13 (8-15) years, p=0.78). Severe CDH correlated significantly with lower PedsQL scores (adjusted β: -18%, 95% CI -28%; -7%, adjusted for age at visit and sex). Lower scores specifically occurred in walking, exercising, social and academic functioning.

CONCLUSION

Severe CDH significantly lowers QOL. This finding is crucial for resource allocation in long-term CDH health surveillance and advocates for regular inclusion of patient experiences in quality improvement efforts.

Postoperative pulmonary vascular growth in patients with congenital diaphragmatic hernia

BACKGROUND

Postoperative pulmonary growth in congenital diaphragmatic hernias (CDH) remains unclear. We investigated postoperative pulmonary vascular growth using serial lung perfusion scintigraphy in patients with CDH.

METHODS

Neonates with left CDH who underwent surgery and postoperative lung perfusion scintigraphy at our institution between 2001 and 2020 were included. Patient demographics, clinical courses, and lung scintigraphy data were retrospectively analyzed by reviewing medical records.

RESULTS

Twenty-one patients with CDH were included. Of these, 10 underwent serial lung scintigraphy. The ipsilateral perfusion rate and median age on the 1st and serial lung scintigraphy were 32% (34 days) and 33% (3.6 years), respectively. Gestational age at prenatal diagnosis (p = 0.02), alveolar-arterial oxygen difference (A-aDO2) at birth (p = 0.007), and preoperative nitric oxide (NO) use (p = 0.014) significantly correlated with the 1st lung scintigraphy. No other variables, including operative approach, were significantly correlated with the 1st or serial scintigraphy findings. All patients improved lung perfusion with serial studies [Difference:  + 7.0 (4.3-13.25) %, p = 0.001, paired t-test]. This improvement was not significantly correlated with preoperative A-aDO2 (p = 0.96), NO use (p = 0.28), or liver up (p = 0.90). The difference was significantly larger in patients who underwent thoracoscopic repair than in those who underwent open abdominal repair [+ 10.6 (5.0-17.1) % vs. + 4.25 (1.2-7.9) %, p = 0.042].

CONCLUSION

Our study indicated a postoperative improvement in ipsilateral lung vascular growth, which is possibly enhanced by a minimally invasive approach, in patients with CDH.

Risk Factors for Preoperative Pneumothorax in Neonates With Isolated Left-Sided Congenital Diaphragmatic Hernia: An International Cohort Study

BACKGROUND

We aimed to investigate the clinical characteristics and outcomes of patients with isolated left-sided congenital diaphragmatic hernia (CDH) who developed preoperative pneumothorax and determine its risk factors.

METHODS

We performed an international cohort study of patients with CDH enrolled in the Congenital Diaphragmatic Hernia Study Group registry between January 2015 and December 2020. The main outcomes assessed included survival to hospital discharge and preoperative pneumothorax development. The cumulative incidence of pneumothorax was estimated by the Gray test. The Fine and Gray competing risk regression model was used to identify the risk factors for pneumothorax.

RESULTS

Data for 2858 neonates with isolated left-sided CDH were extracted; 224 (7.8%) developed preoperative pneumothorax. Among patients with a large diaphragmatic defect, those with pneumothorax had a significantly lower rate of survival to discharge than did those without. The competing risks model demonstrated that a patent ductus arteriosus with a right-to-left shunt flow after birth (hazard ratio [HR]: 1.78; 95% confidence interval [CI]: 1.21-2.63; p = 0.003) and large defects (HR: 1.65; 95% CI: 1.13-2.42; p = 0.01) were associated with an increased risk of preoperative pneumothorax. Significant differences were observed in the cumulative incidence of pneumothorax depending on defect size and shunt direction (p < 0.001).

CONCLUSIONS

Pneumothorax is a significant preoperative complication associated with increased mortality in neonates with CDH, particularly in cases with large defects. Large diaphragmatic defects and persistent pulmonary hypertension were found to be risk factors for preoperative pneumothorax development.

LEVEL OF EVIDENCE

LEVEL Ⅲ Retrospective Comparative Study.

Cardiopulmonary Morbidity in Adults Born With Congenital Diaphragmatic Hernia

OBJECTIVES

Studies concerning cardiopulmonary outcomes of adults born with congenital diaphragmatic hernia (CDH) are sparse. Moreover, they don't include participants who have been treated with extracorporeal membrane oxygenation (ECMO) during the neonatal period. This study evaluated the cardiopulmonary morbidities in young adults born with CDH.

METHODS

We assessed 68 participants between the ages of 18 and 30 years. The assessment included auxology assessment, lung function tests, pulmonary imaging, cardiopulmonary exercise testing, and echocardiography.

RESULTS

Lung function parameters in the overall group were significantly worse than normal values. Mean (SD) scores postbronchodilator forced expiratory volume in 1 second were -2.91 (1.38) in the ECMO-treated and -1.20 (1.53) in the non-ECMO-treated participants. Chest computed tomography scans showed mild to moderate abnormal lung structure in all ECMO-treated participants, and to a lesser extent in non-ECMO treated participants. A recurrent diaphragmatic defect was observed in 77% of the ECMO-treated group and in 43% of the non-ECMO-treated group. Except for 2 cases with acute symptoms, no clinical problems were noted in cases of recurrence. Cardiopulmonary exercise testing revealed mean (SD) percentage predicted peak oxygen consumption per kilogram of 73 (14)% and 88 (16)% in ECMO-treated and non-ECMO-treated participants, respectively. The mean (SD) workload was normal in the non-ECMO-treated group (111 [25]% predicted); in the ECMO-treated group, it was 89 (23)%. Cardiac evaluation at rest revealed no signs of pulmonary hypertension.

CONCLUSIONS

In young adults who survived treatment of CDH, significant pulmonary morbidity, reduced exercise capacity, and frequent hernia recurrence should be anticipated. Lifelong follow-up care, with the emphasis on prevention of further decline, is to be recommended.

Maternal and Neonatal Outcomes After Ex-Utero Intrapartum Treatment for Congenital Diaphragmatic Hernia: A Case Series

INTRODUCTION

 Despite advances in neonatal intensive care, fetuses with congenital diaphragmatic hernia (CDH) remain to have a poor prognosis. Exclusive postnatal treatment is inadequate in patients with moderate CDH (observed than expected lung-to-head ratio [O/E LHR] 26-45%) and can lead to respiratory failure at birth, requiring extracorporeal membrane oxygenation in 75% of cases. An ex-utero intrapartum treatment (EXIT) procedure may be beneficial in these cases, improving the fetal-neonatal transition.

MATERIAL AND METHODS

 We review all pregnancies with fetal isolated left CDH with moderate O/E LHR delivered by EXIT in our center from January 2007 to December 2022. Maternal and neonatal variables were analyzed. As primary outcomes, we included neonatal survival and mortality rates, surgical and infectious complications, uterine scar dehiscence, and blood loss during EXIT. As secondary outcomes, we studied recurrences of the diaphragmatic defect, long-term evolution, subsequent pregnancies, and mode of delivery.

RESULTS

 A total of 14 patients were delivered by the EXIT procedure, with a neonatal survival rate of 85.7%. All these children had optimal physical and neurocognitive development and no pulmonary morbidity. We found no major complications and 7.1% of minor maternal complications. There were no cases of surgical wound infection or endometritis. The median decrease in hemoglobin during the EXIT procedure was 1.9 mg/dL, and only one case required postoperative transfusion. Two out of the 14 women became pregnant again, and both pregnancies were uneventful.

CONCLUSIONS

 In our series, the EXIT procedure allows for adequate airway management associated with a high neonatal survival rate in patients with moderate O/E LHR CDH, with a low rate of neonatal and maternal complications.

Impact of a standardized management guideline for infants with CDH: A single-center experience

BACKGROUND

Infants with congenital diaphragmatic hernia (CDH) are at high risk of death, even despite extracorporeal membrane oxygenation (ECMO) support. In January 2012 we implemented a standardized clinical practice guideline (CPG) to manage infants with CDH. We hypothesized that infants with CDH managed with CPG had better clinical outcomes, less ECMO utilization, and increased survival to discharge.

METHODS

We conducted a retrospective pre-post study of infants with CDH admitted between January 2007 and July 2021 (n = 133). Patients were divided into Cohort 1, pre-CPG (January 2007 to December 2011, n = 54), and Cohort 2, post-CPG (January 2012 to July 2021, n = 79).

RESULTS

More patients in Cohort 1 were small for gestational age than in Cohort 2. No other patient demographics were different between cohorts. Cohort 2 had significantly lower ECMO utilization as compared to Cohort 1 (18% vs 50%, p<0.001). Cohort 2 had significantly higher survival to discharge compared to Cohort 1 (85% vs 57%, p<0.001). Survival for ECMO-treated patients in Cohort 2 was significantly higher than in Cohort 1 (71% vs 26%, p = 0.005). In Cohort 1, 70% of the non-survivors were repaired, of which 81% were repaired on ECMO. In Cohort 2, 8% of the non-survivors were repaired, none on ECMO. Only 3% in Cohort 2 were discharged with pulmonary hypertension medication.

CONCLUSIONS

A standardized CPG to manage patients with CDH decreased ECMO utilization and improved clinical outcomes including survival to discharge. Refinement of management strategies, implementation of new interventions, and meticulous care can improve outcomes in patients with CDH.

Long-term outcomes in newborn surgery

This article describes the common methods to study long-term outcomes in patients who have undergone major surgery in newborn period. It also sums up today's knowledge on the long-term outcome of some classic newborn surgical conditions. The analysis of long-term outcomes is important to pediatric surgeons. Knowledge of long-term outcome can guide the patient's management and principles of the follow-up throughout the patient's childhood. It also aims to give the parents of the patient a realistic picture on the development of their child. Recent data have shown that many patients who have undergone major surgery during early childhood have significant functional aberrations at adult age. Some of these have a profound influence on the quality of life of these patients.

Long term outcomes in CDH: Cardiopulmonary outcomes and health related quality of life

BACKGROUND

With improvements in clinical management and an increase in CDH survivorship there is a crucial need for better understanding of long-term health outcomes in CDH.

AIM

To investigate the prevalence of cardiopulmonary health morbidity and health related quality of life (HRQoL) in CDH survivors.

METHODS

We included all studies (n = 65) investigating long-term cardiopulmonary outcomes in CDH patients more than 2 years published in the last 30 years. The Newcastle-Ottawa Scale and the CASP checklist for cohort studies were utilized to assess study quality. Results were reported descriptively and collated by age group where possible.

RESULTS

The incidence of pulmonary hypertension was highly variable (4.5-38%), though rates (%) appeared to diminish after 5 years of age. Lung function indices and radiological outcomes were frequently abnormal, and Health Related Quality of Life (HRQoL) reduced also. Long term diseases notably emphysema and COPD are not yet fully described in the contemporary literature.

CONCLUSION

This study underscores cardiopulmonary health morbidity and a reduced HRQoL among CDH survivors. Where not already available dedicated multidisciplinary follow-up clinics should be established to support these vulnerable patients transition safely into adulthood. Future research is therefore needed to investigate the risk factors for cardiopulmonary ill health and morbidity in CDH survivors.

TYPE OF STUDY

Systematic review of case control and cohort studies.

Survivors of congenital diaphragmatic hernia repair face barriers to long-term follow-up care

BACKGROUND

Congenital diaphragmatic hernia (CDH) carries high morbidity and mortality, and survivors commonly have neurodevelopmental, gastrointestinal, and pulmonary sequela requiring multidisciplinary care well beyond repair. We predict that following hospitalization for repair, CDH survivors face many barriers to receiving future medical care.

METHODS

A retrospective review was conducted of all living CDH patients between ages 0 to 12 years who underwent repair at Riley Hospital for Children (RHC) from 2010 through 2019. Follow-up status with specialty providers was reviewed, and all eligible families were contacted to complete a survey regarding various aspects of their child's care, including functional status, quality of life, and barriers to care. Bivariate analysis was applied to patient data (P < 0.05 was significant) and survey responses were analyzed qualitatively.

RESULTS

After exclusions, 70 survivors were contacted. Thirty-three (47%) were deemed lost to follow up to specialist providers, and were similar to those who maintained follow-up with respect to defect severity type (A-D, P = 0.57), ECMO use (P = 0.35), number of affected organ systems (P = 0.36), and number of providers following after discharge (P = 0.33). Seventeen (24%) families completed the survey, of whom eight (47%) were deemed lost to follow up to specialist providers. Families reported distance and time constraints, access to CDH-specific information and care, access to CDH-specific resources, and access to healthcare as significant barriers to care. All respondents were interested in a multidisciplinary CDH clinic.

CONCLUSIONS

CDH survivors require multidisciplinary care beyond initial repair, but attrition to follow-up after discharge is high. A multidisciplinary CDH clinic may address caregivers' perceived barriers.

Congenital malformations potentially affecting respiratory function: multidisciplinary approach and follow-up

Background and aim.

Congenital malformations such as oesophageal atresia (OA) and tracheoesophageal fistula (TOF), congenital pulmonary airway malformations (CPAMs), congenital diaphragmatic hernia (CDH) and vascular rings (VRs) can affect lung development and respiratory function. This observational study describes our multidisciplinary approach and respiratory follow-up of children with such congenital malformations.

Methods.

Clinical data of children followed at the Pediatric Respiratory Unit of Parma University Hospital (Italy) between January 2015 and January 2020 were collected.

Results.

Twenty-three patients with congenital malformation affecting lung development were identified. Almost half of our patients were diagnosed with fetal ultrasound. Children attended the clinic at a mean age of 3 (3.7) years and follow-up visits were scheduled every 6 months average. More than half of our patients were hospitalized for lower respiratory tract infections. Six out of 9 children able to perform spirometry showed anomalies in lung function. Chest physiotherapy was recommended especially in children with OA.

Conclusions.

Children with congenital malformations affecting lung development are at risk of short and long-term respiratory complications, especially in the first years of life. OA was the malformation more associated to respiratory problems. Multidisciplinary approach and appropriate personalized follow-up are recommended for the best management of these children. (www.actabiomedica.it)

Risk factors for pneumothorax associated with isolated congenital diaphragmatic hernia: results of a Japanese multicenter study

PURPOSE

This study aimed to elucidate the clinical characteristics of neonates with congenital diaphragmatic hernia (CDH) associated with pneumothorax and evaluate the risk factors for the development of pneumothorax.

METHODS

A retrospective cohort study was conducted in the 15 institutions participating in the Japanese CDH Study Group. A total of 495 neonates with isolated CDH who were born between 2011 and 2018 were analyzed in this study.

RESULTS

Among the 495 neonates with isolated CDH, 52 (10.5%) developed pneumothorax. Eighteen (34.6%) patients developed pneumothorax before surgery, while 34 (65.4%) developed pneumothorax after surgery. The log-rank test showed that the cumulative survival rate was significantly lower in patients with pneumothorax than in those without pneumothorax. Univariate analysis revealed significant differences between patients with pneumothorax and those without pneumothorax with regard to the best oxygenation index within 24 h after birth, mean airway pressure (MAP) higher than 16 cmH₂O, diaphragmatic defect size, and need for patch closure. Multiple logistic regression analysis indicated that only the MAP was associated with an increased risk of pneumothorax.

CONCLUSIONS

The cumulative survival rate was significantly lower in isolated CDH patients with pneumothorax than in those without pneumothorax. A higher MAP was a risk factor for pneumothorax in CDH patients.

Sildenafil for Antenatal Treatment of Congenital Diaphragmatic Hernia: From Bench to Bedside

BACKGROUND

Persistent pulmonary hypertension (PPH) is one of the main causes of mortality and morbidity in infants affected by congenital diaphragmatic hernia (CDH). Since the structural changes that lead to PPH take place already in utero, a treatment starting in the prenatal phase may prevent the occurrence of this complication.

OBJECTIVE

To summarize the development process of antenatal sildenafil for CDH.

METHODS

The pharmacokinetics and efficacy of sildenafil have been assessed in the rat and the rabbit model. The transfer of the drug through the human placenta has been measured with the ex-vivo placenta perfusion model. Results from this experiment are being incorporated in a pregnancy-physiologically based pharmacokinetic (p- PBPK) model. A phase I-IIb placental transfer and safety study is ongoing.

RESULTS

Sildenafil administration to pregnant rats and rabbits led to therapeutic foetal drug levels without maternal and foetal toxicity, although it was associated with impaired vascular development in foetuses with nonhypoplastic lungs. Peak concentrations and 24-hour exposure were higher in pregnant rabbits compared to nonpregnant ones. In rat and rabbit foetuses with CDH, sildenafil rescued the lung vascular anomalies and partially improved parenchymal development. Sildenafil crossed the human placenta at a high rate ex-vivo, independently from the initial maternal concentration.

CONCLUSION

There is preclinical evidence that maternally administered sildenafil prevents the vascular changes that lead to PPH in CDH newborns. The phase I/IIb clinical study together with the p-PBPK model will define the maternal dose needed for a therapeutic effect in the foetus. Foetal safety will be investigated both in the clinical study and in the sheep. The final step will be a multicentre, randomized, placebo-controlled trial.

Left congenital diaphragmatic hernia-associated musculoskeletal deformities

AIM

With the advancement in the treatment strategies of congenital diaphragmatic hernia (CDH), there is an increase in the survival rates. This fact leads to an increase in the morbidity and extrapulmonary complications in the long term such as failure to thrive, hernia recurrence, neurodevelopmental delay, gastrointestinal problems, and musculoskeletal anomalies. Herein, we aim to investigate the association between the long-term musculoskeletal complications in CDH patients regarding the defect size, repair type, and perinatal parameters.

METHODS

After Institutional Review Board approval was obtained (2017-6361), a retrospective chart review was performed on CDH patients from 2003 to 2016. Patients who were operated due to left-sided isolated congenital diaphragmatic hernia and survived to date were included in the study. Data were collected on demographics, preoperative characteristics, operative interventions, and postoperative outcomes. Statistical analysis was performed with IBM SPSS Statistics 20.0.0 (Chicago, IL).

RESULTS

There were 98 patients with left CDH of whom 33 (33.7%) had primary repair, 25 (25.5%) had patch repair, and 40 (40.8%) had muscle flap repair. The median age of the patients was 6.00 ± 3.83 years. 45 patients (45.9%) had large diaphragmatic defects, 28 patients (28.6%) had at least one type of musculoskeletal deformities, 2 of which were pectus carinatum, 16 were pectus excavatum, and 18 were scoliosis. CDH patients who had small diaphragmatic defects and repaired with a patch were less likely develop musculoskeletal deformities while who had primary abdominal closure after ventral hernia significantly have more pectus excavatum.

CONCLUSION

Although there was a trend towards an increased risk of the pectus deformity and scoliosis in patients repaired with muscle flap, it did not reach statistical significance. There is a correlation between musculoskeletal deformities and the severity of the CDH.

[Medium and long-term respiratory outcome in patients operated from congenital diaphragmatic hernia: From a series of 56 patients]

INTRODUCTION

Recent advances in prenatal diagnosis, high frequency oscillatory ventilation and pulmonary arterial hypertension (PAH) therapies have progressively improved the survival of patients with congenital diaphragmatic hernia (CDH). However, CDH is associated with high morbidity that affects about half of surviving children. The main sequelae observed are respiratory (asthma, persistent PAH [PPAH], bronchopulmonary dysplasia, respiratory infections) and digestive (gastroesophageal reflux disease [GERD]).

METHOD

This retrospective study focuses on the medium and long-term respiratory evolution of a cohort of 56 children with CDH and operated at Strasbourg University Hospital between 1999 and 2017.

RESULTS

The mean age at assessment was 6,6 years (minimum: 5 months; maximum: 19 years). Seventeen patients (30 %) had asthmatic manifestations. Pulmonary Function Tests (PFT) showed obstructive patterns in 5/11 patients (2 with post-bronchodilator reversibility), and restrictive impairment in 5/11 patients, 3 of whom had thoracic deformity and/or scoliosis. Thirteen patients (23 %) had bronchopulmonary dysplasia. Few patients had recurrent respiratory infections (3.6 %) and chronic respiratory insufficiency (5.3 %). Thirty-nine patients (70 %) presented with an initial PAH, two of whom progressed to PPAH. Sixteen patients (29 %) had thoracic deformity and/or scoliosis and 48 patients (86 %) had GERD, 10 of whom had fundoplication.

CONCLUSION

The long-term respiratory outcome of CDH operated patients is characterized by a moderate prevalence of respiratory symptoms and alterations in PFT that are important to consider in their medical follow-up during adolescence and adulthood. PAH is common in the neonatal period but rarely seems to persist.

Current and future antenatal management of isolated congenital diaphragmatic hernia

Congenital diaphragmatic hernia is surgically correctable, yet the poor lung development determines mortality and morbidity. In isolated cases the outcome may be predicted prenatally by medical imaging. Cases with a poor prognosis could be treated before birth. However, prenatal modulation of lung development remains experimental. Fetoscopic endoluminal tracheal occlusion triggers lung growth and is currently being evaluated in a global clinical trial. Prenatal transplacental sildenafil administration may in due course be a therapeutic approach, reducing the occurrence of persistent pulmonary hypertension, either alone or in combination with fetal surgery.

Pulmonary hypertension's variegated landscape: a snapshot

The many types of pulmonary hypertension (PH) are so protean in their biological origin, histological expression, and natural history that it is difficult to create a summary picture of the disease, or to easily compare and contrast characteristics of one type of PH with another. For newcomers to the field, however, such a picture would facilitate a broad understanding of PH. In this paper, we suggest that four characteristics are fundamental to describing the nature of various types of PH, and that taken together they define a number of patterns of PH expression. These characteristics are histopathology, developmental origin, associated clinical conditions, and potential for resolution. The “snapshot” is a way to concisely display the ways that these signal characteristics intersect in select specific types of PH, and is an effort to summarize these patterns in a way that facilitates a “big picture” comprehension of this disease.

Cardiopulmonary exercise performance is reduced in congenital diaphragmatic hernia survivors

BACKGROUND

Congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia. CDH survivors may have pulmonary morbidity that can decrease cardiopulmonary exercise. We aimed to examine whether cardiopulmonary exercise testing (CPET) results differ in CDH survivors versus healthy age-matched controls and whether CPET results among CDH survivors differ according to self-reported daily activity.

METHODS

In one medical center in Croatia, CDH survivors-patients with surgically corrected CDH who were alive at age 5 years-were invited to participate in spirometry and CPET. Values were compared with those of controls matched 2:1 by age and sex for each CDH survivor aged 7 years or older.

RESULTS

Among 27 CDH survivors aged 5-20 years, 13 (48%) had continued symptoms or spirometric evidence of pulmonary disease. Compared with controls (n = 44), survivors (n = 22) had lower peak oxygen consumption (V˙O2 mean [SD], 35.7 [6.9] vs. 45.3 [8.2] ml/kg per min; P < 0.001). At peak exercise, V˙O2/heart rate (P < 0.001), tidal volume (P = 0.005), and minute ventilation (P < 0.001) were lower in survivors, but the maximal respiratory rate was not different (P = 0.72). Among survivors, mean (SD) V˙O2peak (ml/kg per min) differed by self-reported activity level: athletic, 40.3 (5.0); normal, 35.8 (6.5); and sedentary, 32.1 (6.8) (by ANOVA, P = 0.10 across three groups and P = 0.04 athletic vs. sedentary).

CONCLUSION

More than half of CDH survivors continue to have chronic pulmonary disease. CDH survivors had lower aerobic exercise capacity than controls. Self-reporting information on daily activities may identify CDH patients with low V˙O2max who may benefit from physical training. Pediatr Pulmonol. 2016;51:1320-1329. © 2016 Wiley Periodicals, Inc.

Thoraco-abdominal asymmetry and asynchrony in congenital diaphragmatic hernia

OBJECTIVE

Congenital diaphragmatic hernia (CDH) consists of an incomplete formation of the diaphragm and the subsequent herniation of abdominal bowels. Diaphragmatic defect can be repaired by primary closure or placing a patch. Respiratory follow up usually focuses on spirometric and clinical evaluation. The aim of the study was to assess thoraco-abdominal volumes in CDH patients and to verify whether the action of the diaphragm on the chest wall is altered leading to an asymmetric and asynchronous expansion of the different thoracoabdominal compartments.

PATIENTS AND METHODS

Total and compartmental chest wall volumes and asynchronies were measured by Opto-Electronic Plethysmography in 14 CDH patients (7 M/7F, age 5 ± 2 years, 12 left side operated) and in 9 age matched healthy subjects during quiet spontaneous breathing in supine position. Patients were divided in two groups: five patients with suture (group S) and nine patients with diaphragmatic patch (group P). Pulmonary function was assessed by spirometry and spirometric parameters were expressed as Z-score.

RESULTS

In group P abdominal contribution to tidal volume was lower than healthy controls and group S. Unlike controls, in both CDH groups the right side of pulmonary rib cage moved inward with a correspondent left side expansion during inspiration. In group S, thoraco-abdominal asynchronies were higher than in group P and controls, especially in the right side. Five patients belonging to group P had a spirometric obstructive pattern.

CONCLUSIONS

In overall CDH patients a reduced action of the treated (left) hemi-diaphragm is evident. In patients treated by primary suture, a compensatory action of the right side allows to reach a normal total diaphragmatic displacement and a proper contribution of the whole diaphragm to tidal volume. In patients treated by diaphragmatic patch, instead, thoraco-abdominal asynchronies are prevented.

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).

Predictors of early lung function in patients with congenital diaphragmatic hernia

PURPOSE

Long-term pulmonary outcomes of congenital diaphragmatic hernia (CDH) have demonstrated airflow obstruction in later childhood. We examined pulmonary function data to assess what factors predict lung function in the first three years of life in children with CDH.

METHODS

This was a retrospective study of patients treated for CDH who underwent infant pulmonary function testing (IPFT) between 2006 and 2012. IPFT was performed using the raised volume rapid thoracoabdominal compression technique and plethysmography.

RESULTS

Twenty-nine neonates with CDH had IPFTs in the first 3years of life. Their mean predicted survival using the CDH Study Group equation was 63%±4%. Fourteen infants (48%) required extracorporeal membrane oxygenation (ECMO). The mean age at IPFT was 85.1±5weeks. Airflow obstruction was the most common abnormality, seen in 14 subjects. 12 subjects had air trapping, and 9 demonstrated restrictive disease. ECMO (p=0.002), days on the ventilator (p=0.028), and days on oxygen (p=0.023) were associated with restrictive lung disease.

CONCLUSION

Despite following a group of patients with severe CDH, lung function revealed mild deficits in the first three years of life. Clinical markers of increased severity (ECMO, ventilator days, and prolonged oxygen use) are correlated with reduced lung function.

Pulmonary support on day 30 as a predictor of morbidity and mortality in congenital diaphragmatic hernia

PURPOSE

Congenital diaphragmatic hernia (CDH) is associated with significant in-hospital mortality, morbidity and length-of-stay (LOS). We hypothesized that the degree of pulmonary support on hospital day-30 may predict in-hospital mortality, LOS, and discharge oxygen needs and could be useful for risk prediction and counseling.

METHODS

862 patients in the CDH Study Group registry with a LOS ≥ 30 days were analyzed (2007-2010). Pulmonary support was defined as (1) room-air (n=320) (2) noninvasive supplementation (n=244) (3) mechanical ventilation (n=279) and (4) extracorporeal membrane oxygenation (ECMO, n=19). Cox Proportional hazards and logistic regression models were used to determine the case-mix adjusted association of oxygen requirements on day-30 with mortality and oxygen requirements at discharge.

RESULTS

On multivariate analysis, use of ventilator (HR 5.1, p=.003) or ECMO (HR 19.6, p<.001) was a significant predictor of in-patient mortality. Need for non-invasive supplementation or ventilator on day-30 was associated with a respective 22-fold (p<.001) and 43-fold (p<.001) increased odds of oxygen use at discharge compared to those on room-air.

CONCLUSIONS

Pulmonary support on Day-30 is a strong predictor of length of stay, oxygen requirements at discharge and in-patient mortality and may be used as a simple prognostic indicator for family counseling, discharge planning, and identification of high-risk infants.

Late surgical outcomes among congenital diaphragmatic hernia (CDH) patients: why long-term follow-up with surgeons is recommended

BACKGROUND

CDH patients experience multi-system morbidity. Despite apparent health, late childhood complications do occur. We reviewed the long-term surgical morbidity of our CDH patients to determine whether protracted clinical surveillance is warranted.

METHODS

A single-institution retrospective chart review of all CDH survivors treated from 1999 to 2011 who are followed at our CDH multidisciplinary clinic was performed. Descriptive and statistical analyses were performed to show risk of surgical complications over time.

RESULTS

A total of 187 CDH patients were treated with 160 surviving to discharge (86%). Primary repair was performed in 115 (73%), and 42 (27%) underwent patch repair. CDH recurrence occurred in 23 (15%) at a median time of 0.7 (range 0-8.5) years (65% asymptomatic). Seventy percent of recurrences occurred before 2 years and 17% after 4 years. Bowel obstruction occurred in 12 (8%) at a median time of 0.7 (range 0.2-7.2) years post-repair, and chest deformity occurred in 13 (8%) at a median of 5 (range 1.1-6.8) years. For patch repairs, scoliosis occurred in 4 (10%) patients at a median age of 3 (range 0.6-5) years.

CONCLUSION

Surgical complications in CDH survivors are common, can occur many years later, and are frequently asymptomatic. Long-term surveillance of CDH patients is recommended for early identification and treatment of complications.

Amniotic fluid stem cells rescue both in vitro and in vivo growth, innervation, and motility in nitrofen-exposed hypoplastic rat lungs through paracrine effects

Lung hypoplasia can be prevented in vitro by retinoic acid (RA). Recent evidence suggests that amniotic fluid stem (AFS) cells may integrate injured lungs and influence their recovery. We tested the hypothesis that AFS cells might improve lung growth and motility by paracrine mechanisms. Pregnant rats received either nitrofen or vehicle on E9.5. In vitro E13 embryonic lungs were cultured in the presence of culture medium alone or with RA, basophils, or AFS cells. In vivo green fluorescent protein-expressing (GFP(+)) rat AFS cells were transplanted in nitrofen-exposed rats on E10.5. E13 lung explants were cultured before analysis. The surface, the number of terminal buds, and the frequency of bronchial contractions were assessed. Protein gene product 9.5 (PGP 9.5) and α-actin protein levels were measured. The lung explants transplanted with AFS cells were stained for α-actin, PGP 9.5, and TTF-1. The levels of FGF-10, VEGFα, and TGF-β1 secreted by the AFS cells in the culture medium were measured. Comparison between groups was made by ANOVA. In vitro, the surface, the number of terminal buds, and the bronchial peristalsis were increased in nitrofen+AFS cell explants in comparison with nitrofen-exposed lungs. While nitrofen+RA lungs were similar to nitrofen+AFS ones, basophils did not normalize these measurements. PGP 9.5 protein was decreased in nitrofen lungs, but after adding AFS cells, the value was similar to controls. No differences were found in the expression of α-actin. In vivo, the surface, number of terminal buds, and peristalsis were similar to control after injection of AFS cells in nitrofen-exposed rats. Colocalization with TTF-1-positive cells was found. The levels of FGF-10 and VEGFα were increased in nitrofen+AFS cell explants, while the levels of TGF-β1 were similar to controls. Lung growth, bronchial motility, and innervation were decreased in nitrofen explants and rescued by AFS cells both in vitro and in vivo, similarly to that observed before with RA. The AFS cell beneficial effect was probably related to paracrine action of growth factor secretion.

Exercise capacity, daily activity, and severity of fatigue in term born young adults after neonatal respiratory failure

Little is known about long-term effects of neonatal intensive care on exercise capacity, physical activity, and fatigue in term borns. We determined these outcomes in 57 young adults, treated for neonatal respiratory failure; 27 of them had congenital diaphragmatic hernia with lung hypoplasia (group 1) and 30 had normal lung development (group 2). Patients in group 2 were age-matched, with similar gestational age and birth weight, and similar neonatal intensive care treatment as patients in group 1. All patients were born before the era of extracorporeal membrane oxygenation, nitric oxide administration, and high frequency ventilation. Exercise capacity was measured by cycle ergometry, daily physical activity with an accelerometry-based activity monitor, and fatigue by the fatigue severity scale. Median (range) VO2peak in mL/kg/min was 35.4 (19.6-55.0) in group 1 and 37.6 (15.7-52.7) in group 2. There was a between-group P-value of 0.65 for exercise capacity. Daily activity and fatigue were also similar in both groups. So, residual lung hypoplasia did not play an important role in this cohort. There were no significant associations between exercise capacity and perinatal characteristics. Future studies need to elucidate whether exercise capacity is impaired in patients with more severe lung hypoplasia who nowadays survive.

Follow-up of the survivors of congenital diaphragmatic hernia

INTRODUCTION

Survivors of congenital diaphragmatic hernia have increased with the introduction of new treatment modalities and have been reported to experience ongoing medical morbidity until adulthood.

AIM

To describe the long-term functional impact of congenital diaphragmatic repair on the survivors of a single institution cohort of newborns over a 14-year period.

METHODS

The follow up medical charts of 39 congenital diaphragmatic hernia survivors treated at a tertiary neonatal intensive care unit, from January 1997 to December 2010, were analyzed.

RESULTS

The median age at follow up was 70 (4-162) months. Gastrointestinal sequelae were the most common with 12 (30.7%) patients affected by failure to thrive. Chronic lung disease occurred in 5 (12.8%) patients, neurodevelopmental delay in 5 (12.8%), musculoskeletal sequelae in 6 (15.3%), recurrence of hernia in 4 (10.2%) and 2 (7.6%) were deceased.

CONCLUSION

Congenital diaphragmatic hernia survivors are a group of patients that requires long term periodic follow up in a multidisciplinary setting to provide adequate support and improve their quality of life.

[Congenital diaphragmatic hernia: respiratory and vascular outcomes]

Congenital diaphragmatic hernia (CDH) is a life-threatening anomaly associated with a variable degree of pulmonary hypoplasia (PH) and persistent pulmonary hypertension (PPH). Despite remarkable advances in neonatal resuscitation and intensive care, and new postnatal treatment strategies, the rates of mortality and morbidity in the newborn with CDH remain high as the result of severe respiratory failure secondary to PH and PPH. Later, lung function assessments show obstructive and restrictive impairments due to altered lung structure and lung damage due to prolonged ventilatory support. The long-term consequences of pulmonary hypertension are unknown. Other problems include chronic pulmonary aspiration caused by gastro-oesophageal reflux and respiratory manifestations of allergy such as asthma or rhinitis. Finally, failure to thrive may be caused by increased caloric requirements due to pulmonary morbidity. Follow-up studies that systematically assess long-term sequelae are needed. Based on such studies, a more focused approach for routine multidisciplinary follow-up programs could be established. It is the goal of the French Collaborative Network to promote exchange of knowledge, future research and development of treatment protocols.

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.

Physical activity, fitness, and dyspnea perception in children with congenital diaphragmatic hernia

We assessed whether physical activity could influence the performance and perception of dyspnea in children who were operated on for high risk congenital diaphragmatic hernia (CDH). We hypothesized that CDH children with normal activity would have better lung function and exercise performance level when compared to sedentary CDH subjects. We studied 18 children (11 males and 7 females, mean age 6.6 ± 2.6 years) who were surgically corrected. All children underwent physical examination, ECG at rest, and a maximal exercise stress test on a treadmill to measure the duration of exercise, maximal heart rate and blood pressure, maximal oxygen uptake (VO(2)  max and VO(2)  ml/kg/min). Lung function testing to measure forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV(1) ), and peak expiratory flow (PEF) was also performed. Following the stress test, the Dalhousie dyspnea and effort scale was shown to children as a pictorial panel with three groups of increasing (from 1 to 7) levels of effort perception, throat discomfort, and chest dyspnea. Children were divided into group A (sedentary) and group B (regular physical participation). There was no difference in CDH severity between the two groups. Group A had a statistically significant lower duration of exercise (P < 0.01), maximal oxygen consumption (VO(2)  max P < 0.0001), VO(2)  ml/kg/min (P < 0.001), higher throat closing feeling (P < 0.004), chest dyspnea (P < 0.001), and effort perception (P < 0.04) compared to group B. No differences were found in lung function tests. In conclusion, our data may suggest that children with a history of CDH who are active maintain a higher level of performance with less perception of dyspnea and effort.

Fusionless procedures for the management of early-onset spine deformities in 2011: what do we know?

While attempts to understand them better and treat them more effectively, early-onset deformities have gained great pace in the past few years. Large patient series with long follow-ups that would provide high levels of evidence are still almost non-existent. That there is no safe treatment algorithm defined and agreed upon for this patient population continues to pose a challenge for pediatric spine surgeons. In this review, authors who are well known for their research and experience in the treatment of early-onset scoliosis (EOS) have come together in order to answer those questions which are most frequently asked by other surgeons. The most basic eight questions in this field have been answered succinctly by these authors and a current overview is provided.

Late presentation of congenital diaphragmatic hernia in patients with cystic fibrosis

Late presentation of congenital diaphragmatic hernia (CDH) is unusual, especially in patients with cystic fibrosis (CF). To our knowledge, cases of CDH in CF patients and the combined effects on lung function have not been previously described. Here we report two cases of late presenting CDH in CF patients and describe effects on lung function. Late presentation of CDH in CF patients can cause gastrointestinal or respiratory symptoms and requires a high index of suspicion as well as proper interpretation of imaging. In patients with CF and CDH, lung function abnormalities could include obstructive, restrictive defects, or combined defects.

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.

A prospective comparative evaluation of persistent respiratory morbidity in esophageal atresia and congenital diaphragmatic hernia survivors

PURPOSE

The aim of the study was to compare long-term respiratory morbidity in children after repair of esophageal atresia (EA) or congenital diaphragmatic hernia (CDH).

PATIENTS AND METHODS

Children were seen at 6, 12, and 24 months and 5 years within a prospective longitudinal follow-up program in a tertiary children's hospital. Respiratory morbidity and physical condition were evaluated at all moments. At age 5 years, pulmonary function and maximal exercise performance were tested.

RESULTS

In 3 of 23 atresia patients and 10 of 20 hernia patients, bronchopulmonary dysplasia was developed. Seventeen atresia and 11 hernia patients had recurrent respiratory tract infections mainly in the first years of life. At age 5, 25% of EA and CDH patients measured showed reduced forced expiratory volume in 1 second (z-score < -2). Both atresia and hernia patients showed impaired growth, with catch-up growth at 5 years in patients with EA but not in those with hernia. Maximal exercise performance was significantly below normal for both groups.

CONCLUSIONS

Esophageal atresia and CDH are associated with equal risk of long-term respiratory morbidity, growth impairment, and disturbed maximal exercise performance. Prospective follow-up of EA patients aimed at identifying respiratory problems other than tracheomalacia should be an integral part of interdisciplinary follow-up programs.

Can we improve outcome of congenital diaphragmatic hernia?

This review gives an overview of the disease spectrum of congenital diaphragmatic hernia (CDH). Etiological factors, prenatal predictors of survival, new treatment strategies and long-term morbidity are described. Early recognition of problems and improvement of treatment strategies in CDH patients may increase survival and prevent secondary morbidity. Multidisciplinary healthcare is necessary to improve healthcare for CDH patients. Absence of international therapy guidelines, lack of evidence of many therapeutic modalities and the relative low number of CDH patients calls for cooperation between centers with an expertise in the treatment of CDH patients. The international CDH Euro-Consortium is an example of such a collaborative network, which enhances exchange of knowledge, future research and development of treatment protocols.

Tracheal innervation is abnormal in rats with experimental congenital diaphragmatic hernia

BACKGROUND

Tracheobronchial motility influences lung development. Lung hypoplasia and lung sequelae accompany congenital diaphragmatic hernia (CDH) in which the vagus nerves and esophageal innervation are abnormal. As the vagus supplies tracheal innervation, this study tested the hypothesis that it might also be abnormal in rats with CDH.

MATERIAL AND METHODS

Intrinsic ganglia were counted and measured in whole mount acetylcholinesterase-stained tracheas from CDH and control E21 fetal rats. The relative surfaces occupied by neural structures were measured in tracheal sections immunostained for p75(NTR) and PGP 9.5. PGP 9.5 protein and mRNA expression were determined. Mann-Whitney tests were used for comparisons between groups using P < .05 as significant.

RESULTS

p75(NTR) staining showed the neural crest origin of tracheal innervation. Scarce neural structures and smaller ganglia were found in CDH fetuses. PGP 9.5 protein expression was decreased in CDH fetuses, whereas PGP 9.5 mRNA levels were increased in comparison with controls.

CONCLUSIONS

Decreased density of neural structures and size of intramural ganglia, reduced expression of neural tissue and PGP 9.5 protein, and increased levels of PGP 9.5 mRNA reveal deficient tracheal innervation in rats with CDH. If similar anomalies exist in the human condition, they could contribute to explaining the pathogenesis of lung hypoplasia and bronchopulmonary sequelae.

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.

Postnatal management and long-term outcome for survivors with congenital diaphragmatic hernia

Significant advances in the postnatal management of patients with congenital diaphragmatic hernia (CDH) have resulted in a remarkable improvement in survival rates over the past two decades. The success of current postnatal management of CDH patients has rendered fetal intervention to be limited to the most severe cases, and the role for prenatal treatment of CDH patients remains unclear. The adoption of lung-preserving strategies including high-frequency oscillatory ventilation (HFOV) and extracorporeal membrane oxygenation (ECMO) have improved CDH outcomes especially in those patients with significant ventilatory or circulatory compromise. Survival rates of up to 90% are being reported in some high-volume centers. However, the increased survival in CDH patients has been accompanied by an increase in neurological, nutritional and musculoskeletal morbidity among the long-term survivors. This has resulted in the need to provide resources for the long-term follow-up and support of this patient population. In this article, the postnatal management strategies and primary and secondary outcomes of high-volume international pediatric surgical centers will be reviewed. Finally, the role of a multidisciplinary management team for the follow-up of long-term CDH survivors will be discussed.

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.

Congenital diaphragmatic hernia

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

Antenatal and postnatal lung and vascular anatomic and functional studies in congenital diaphragmatic hernia: implications for clinical management

Congenital diaphragmatic hernia is characterized by fetal and neonatal lung hypoplasia as well as vascular hypoplasia. Antenatal imaging studies have been performed that attempt to quantify the degree of hypoplasia and its impact on infant prognosis. Prenatal and perinatal growth of the lung and vasculature are interdependent and their continued coordinated growth is critical for survival after birth in this patient population. Lung protection strategies appear to improve survival in newborns with diaphragmatic hernia, but a subset of infants remain who demonstrate sufficiently severe lung hypoplasia that we are unable to provide support long-term after birth. Fetal intervention is a strategy designed to enhance fetal lung growth towards improving survival in this most severely affected group, though other therapies to enhance postnatal lung and vascular growth should be concurrently investigated. However, any of these interventions will require careful selection of those infants at risk for poor outcome and thorough follow up, since long-term morbidity is significant in children with diaphragmatic hernia.

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.

Pulmonary function and exercise testing in adult survivors of congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is accompanied by pulmonary hypoplasia and structural abnormalities of the pulmonary vascular bed. It is unknown whether pulmonary function, exercise capacity, and gas exchange during exercise are impaired in adult CDH survivors. The objective of this study was to assess the long-term pulmonary function, exercise capacity, and gas exchange during exercise and relate these findings with quality of life. Of the 23 patients eligible for this study, 12 adult CDH survivors (mean age, 24.3 +/- 4.1 years) with high-risk CDH agreed to participate. Pulmonary function tests, diffusion capacity, and a cardiopulmonary exercise test (CPET) were performed. The FEV1 (mean z-score +/- SD; -1.30 +/- 1.37), FEF25-75% (-1.49 +/- 1.14), and the KCO (-1.03 +/- 1.24) were found to be lower in CDH survivors. The RV/TLC ratio (28.2% +/- 5.0%) was found to be higher. Despite these abnormalities, percent predicted work load (102% +/- 17.2%) and percent predicted maximal oxygen uptake (90.8% +/- 18.9%) were normal in most of the patients. The quality of life of CDH survivors, assessed with the SF-36 questionnaire, is comparable to the general population. Comparison of participants to non-participants did not reveal significant differences in clinical characteristics. In this first study assessing pulmonary function in adult survivors of CDH, mild airway obstruction was observed in most of the patients together with a slightly reduced diffusion capacity for CO. Exercise capacity and gas exchange parameters were normal in this group, indicating that patients do not have a physical impairment, as reflected by a normal quality of life of CDH patients.

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.

Peristalsis of airway smooth muscle is developmentally regulated and uncoupled from hypoplastic lung growth

Prenatal airway smooth muscle (ASM) peristalsis appears coupled to lung growth. Moreover, ASM progenitors produce fibroblast growth factor-10 (FGF-10) for lung morphogenesis. Congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia, FGF-10 deficiency, and postnatal ASM dysfunction. We hypothesized ASM dysfunction emerges in tandem with, and may contribute toward, the primordial lung hypoplasia that precedes experimental CDH. Spatial origin and frequency of ASM peristaltic waves were measured in normal and hypoplastic rat lungs cultured from day 13.5 of gestation (lung hypoplasia was generated by nitrofen dosing of pregnant dams). Longitudinal lung growth was assayed by bud counts and tracing photomicrographs of cultures. Coupling of lung growth and peristalsis was tested by stimulation studies using serum, FGF-10, or nicotine and inhibition studies with nifedipine or U0126 (MEK1/2 inhibitor). In normal lung, ASM peristalsis is developmentally regulated: proximal ASM becomes quiescent (while retaining capacity for cholinergic-stimulated peristalsis). However, in hypoplastic lung, spontaneous proximal ASM activity persists. FGF-10 corrects this aberrant ASM activity in tandem with improved growth. Stimulation and inhibition studies showed that, unlike normal lung, changes in growth or peristalsis are not consistently accompanied by parallel modulation of the other. ASM peristalsis undergoes FGF-10-regulated spatiotemporal development coupled to lung growth: this process is disrupted early in lung hypoplasia. ASM dysfunction emerges in tandem with and may therefore contribute toward lung hypoplasia in CDH.