Pulmonary morbidity in 100 survivors of congenital diaphragmatic hernia monitored in a multidisciplinary clinic

Functional lung imaging of 2-year-old children after congenital diaphragmatic hernia repair using dynamic mode decomposition MRI

OBJECTIVES

To investigate the feasibility of non-contrast-enhanced functional lung imaging in 2-year-old children after congenital diaphragmatic hernia (CDH) repair.

METHODS

Fifteen patients after CDH repair were examined using non-contrast-enhanced dynamic magnetic resonance imaging (MRI). For imaging two protocols were used during free-breathing: Protocol A with high temporal resolution and Protocol B with high spatial resolution. The dynamic images were then analysed through a recently developed post-processing method called dynamic mode decomposition (DMD) to obtain ventilation and perfusion maps. The ventilation ratios (VRatio) and perfusion ratios (QRatio) of ipsilateral to contralateral lung were compared to evaluate functional differences. Lastly, DMD MRI-based perfusion results were compared with perfusion parameters obtained using dynamic contrast-enhanced (DCE) MRI to assess agreement between methods.

RESULTS

Both imaging protocols successfully generated pulmonary ventilation (V) and perfusion (Q) maps in all patients. Overall, the VRatio and QRatio values were 0.84 ± 0.19 and 0.70 ± 0.24 for Protocol A, and 0.88 ± 0.18 and 0.72 ± 0.23 for Protocol B, indicating reduced ventilation ( p < 0.05 ) and perfusion ( p < 0.01 ) on the ipsilateral side. Moreover, there is a very strong positive correlation ( r > 0.89 , p < 0.01 ) and close agreement between DMD MRI-based perfusion values and DCE MRI-based perfusion parameters.

CONCLUSIONS

DMD MRI can obtain pulmonary functional information in 2-year-old CDH patients. The results obtained with DMD MRI correlate with DCE MRI, without the need for ionising radiation or exposure to contrast agents. While further studies with larger cohorts are warranted, DMD MRI is a promising option for functional lung imaging in CDH patients.

CLINICAL RELEVANCE STATEMENT

We demonstrate that pulmonary ventilation and perfusion information can be obtained in 2-year-old patients after CDH repair, without the need for ionising radiation or contrast agents by utilising non-contrast-enhanced MRI acquisitions together with dynamic mode decomposition analysis.

KEY POINTS

• Non-contrast-enhanced functional MR imaging is a promising option for functional lung imaging in 2-year-old children after congenital diaphragmatic hernia. • DMD MRI can generate pulmonary ventilation and perfusion maps from free-breathing dynamic acquisitions without the need for ionising radiation or contrast agents. • Lung perfusion parameters obtained with DMD MRI correlate with perfusion parameters obtained using dynamic contrast-enhanced MRI.

Disparities in Healthcare Utilization: An Analysis of Disease Specific and Patient Level Factors in a Congenital Diaphragmatic Hernia Clinic

OBJECTIVES

Our study examines if the disease severity profile of our Congenital Diaphragmatic Hernia (CDH) patient cohort adherent to long-term follow-up differs from patients lost to follow-up after discharge and examines factors associated with health care utilization.

METHODS

Retrospective review identified CDH survivors born 2005-2019 with index repair at our institution. Primary outcome was long-term follow-up status: "active" or "inactive" according to clinic guidelines. Markers of CDH disease severity including CDH defect classification, oxygen use, tube feeds at discharge, and sociodemographic factors were examined as exposures.

RESULTS

Of the 222 included patients, median age [IQR] was 10.2 years [6.7-14.3], 61% male, and 57 (26%) were insured by Medicaid. Sixty-three percent (139/222) of patients were adherent to follow-up. Seventy-six percent of patients discharged on tube feeds had active follow-up compared to 55% of patients who were not, with similar findings for oxygen at discharge (76% vs. 55%). Kaplan-Meier analysis showed patients with smaller defect size had earlier attrition compared to patients with larger defect size. Other race (Hispanic, Asian, Middle Eastern) patients had 2.87 higher odds of attrition compared to white patients (95% CI 1.18-7.0). Medicaid patients had 2.64 higher odds of attrition compared to private insurance (95% CI 1.23-5.66).

CONCLUSION

Loss to follow-up was associated with race and insurance type. Disease severity was similar between the active and inactive clinic cohorts. Long-term CDH clinic publications should examine attrition to ensure reported outcomes reflect the discharged population. This study identified important factors to inform targeted interventions for follow-up adherence.

LEVEL OF EVIDENCE

Level III.

Comparison of conventional mechanical ventilation and high-frequency oscillatory ventilation in congenital diaphragmatic hernias: a systematic review and meta-analysis

Outcomes of conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV) in patients with congenital diaphragmatic hernia (CDH) were compared through a systematic review and meta-analysis. Outcome measures included mortality and incidence of chronic lung disease (CLD). Odds ratio (OR) and 95% confidence interval (95%CI) were evaluated. Subgroup analyses were performed according to the strategy for applying HFOV in CDH patients. Group A: CMV was initially applied in all CDH patients, and HFOV was applied in unstable patients. Group B: chronologically analyzed. (CMV and HFOV era) Group C: CMV or HFOV was used as the initial MV. Of the 2199 abstracts screened, 15 full-text articles were analyzed. Regarding mortality, 16.7% (365/2180) and 32.8% (456/1389) patients died in CMV and HFOV, respectively (OR, 2.53; 95%CI 2.12-3.01). Subgroup analyses showed significantly worse, better, and equivalent mortality for HFOV than that for CMV in group A, B, and C, respectively. CLD occurred in 32.4% (399/1230) and 49.3% (369/749) patients in CMV and HFOV, respectively (OR, 2.37; 95%CI 1.93-2.90). The evidence from the literature is poor. Mortality and the incidence of CLD appear worse after HFOV in children with CDH. Cautious interpretation is needed due to the heterogeneity of each study.

Fetal Lung Volume Appears to Predict Respiratory Morbidity in Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) is associated with pulmonary hypoplasia and respiratory morbidity. To assess whether respiratory morbidity during the first 2 years of life in infants with left-sided CDH is associated with fetal lung volume (FLV) evaluated by the observed-to-expected FLV ratio (o/e FLV) on antenatal magnetic resonance imaging (MRI). In this retrospective study, o/e FLV measures were collected. Respiratory morbidity in the first 2 years of life was studied according to two endpoints: treatment with inhaled corticosteroids for >3 consecutive months and hospitalization for any acute respiratory disease. The primary outcome was a favorable progression defined by the absence of either endpoint. Forty-seven patients were included. The median o/e FLV was 39% (interquartile range, 33-49). Sixteen (34%) infants were treated with inhaled corticosteroids and 13 (28%) were hospitalized. The most efficient threshold for a favorable outcome was an o/e FLV ≥ 44% with a sensitivity of 57%, specificity of 79%, negative predictive value of 56%, and positive predictive value of 80%. An o/e FLV ≥ 44% was associated with a favorable outcome in 80% of cases. These data suggest that lung volume measurement on fetal MRI may help to identify children at lower respiratory risk and improve information during pregnancy, patient characterization, decisions about treatment strategy and research, and personalized follow-up.

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.

Respiratory syncytial virus bronchiolitis in congenital diaphragmatic hernia: A systematic review of prevalence rates and palivizumab prophylaxis

BACKGROUND

The seasonality of respiratory syncytial virus (RSV) epidemics have been disrupted during the COVID-19 pandemic, possibly because of lockdowns and social restrictions reducing viral transmission. Given uncertainties around the severity of upcoming RSV bronchiolitis epidemics, debate exists whether palivizumab (RSV prophylaxis) should be administered to infants with Congenital Diaphragmatic Hernia (CDH), who may be vulnerable due to lung hypoplasia and pulmonary hypertension.

AIM

To evaluate (1) if CDH infants have higher risk of admission with RSV bronchiolitis than infants in the general population; (2) if palivizumab prophylaxis may reduce this risk.

METHODS

We included all eligible studies examining the risk(s) of RSV-positive bronchiolitis requiring hospital admission in (1) CDH infants without palivizumab prophylaxis versus infants in the general population and (2) CDH infants with prophylaxis versus CDH infants without prophylaxis. The primary outcome evaluated was the risk of admission with RSV bronchiolitis. Data are reported descriptively and meta-analysed when appropriate.

RESULTS

Three eligible retrospective cohort studies were identified: one study found CDH to be an independent risk factor for RSV hospitalisation (odds ratio, 3.30; 95% confidence interval [CI], 2.01-4.4); two studies compared RSV hospitalisation rates in CDH patients who had palivizumab versus those that did not. The pooled risk ratio was 1.11 (95% CI, 0.29-4.23; p = .88). Overall, the quality of evidence was considered poor and one study was industry funded.

CONCLUSION

Whether CDH infants are at particular risk of severe bronchiolitis remains unclear. There is no evidence from this current systematic review that CDH infants should routinely receive palivizumab vaccination prophylaxis.

Clinical characteristics and outcomes of the right congenital diaphragmatic hernia compared to the left: a 10-year single-center experience

PURPOSE

The features of right-sided congenital diaphragmatic hernias (RCDHs) are quite different from those of left-sided CDHs (LCDHs). We have summarized the features of RCDHs experienced in our institution.

METHODS

This retrospective study analyzed the cases of patients with CDH registered at our institution between 2011 and 2020. Defects on each side were compared based on prenatal diagnosis, medical treatment, type of surgery, and outcomes.

RESULTS

A total of 101 patients underwent surgery at our institution during the neonatal period, and 11 had RCDHs. RCDHs and LCDHs were significantly different in terms of extracorporeal membrane oxygenation (36% vs. 6%, p = 0.002), patch repair (81% vs. 28%, p < 0.001), recurrence rate (36% vs. 11%, p = 0.022), and length of hospital stay (117 days vs. 51 days, p = 0.012). The severity of the fetal diagnosis did not reflect postnatal severity. All patients with RCDH survived to discharge, and there was no significant difference in survival rate between the right and left sides.

CONCLUSION

Neonates with RCDH required more intensive treatments; however, the survival rate was comparable between RCDH and LCDH. RCDH was significantly different from LCDH and an optimal treatment strategy for RCDHs should be established.

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.

Prenatal stomach position predicts gastrointestinal morbidity at 2 years in fetuses with left-sided congenital diaphragmatic hernia

OBJECTIVE

The long-term morbidity associated with isolated left-sided congenital diaphragmatic hernia (CDH) has been described previously. However, antenatal criteria impacting gastrointestinal morbidity (GIM) are not yet defined. The objective of this study was to evaluate the effect of fetal stomach position on the risk of GIM at 2 years of age in children with left-sided CDH.

METHODS

This was a retrospective, observational multicenter cohort study of data obtained from January 2010 to January 2014, that included patients whose fetus had isolated left-sided CDH, with or without fetal endoscopic tracheal occlusion (FETO). Prenatal maternal, fetal and pediatric data were collected. Fetal stomach position was evaluated a posteriori by two observers, using ultrasound images at the level of the four-chamber view of the heart that had been obtained to calculate the observed-to-expected lung-area-to-head-circumference ratio (O/E-LHR). Fetal stomach position was graded as follows: Grade 1, stomach not visualized; Grade 2, stomach visualized anteriorly, next to the apex of the heart, with no structure in between the stomach and the sternum; Grade 3, stomach visualized alongside the left ventricle of the heart, and abdominal structures anteriorly; or Grade 4, as Grade 3 but with stomach posterior to the level of the atrioventricular heart valves. The primary outcome was GIM at 2 years of age, assessed in a composite manner, including the occurrence of gastroesophageal reflux disease, need for gastrostomy, duration of parenteral and enteral nutrition and persistence of oral aversion. Regression analysis was performed in order to investigate the effect of O/E-LHR, stomach position and FETO on various GIM outcome variables.

RESULTS

Forty-seven patients with fetal left-sided CDH were included in the analysis. Thirteen (27.7%) infants did not meet the criterion of exclusive oral feeding at 2 years of age. Fetal stomach position grade was associated significantly and independently with the duration of parenteral nutrition (odds ratio (OR), 19.86; P = 0.031) and persistence of oral aversion at 2 years (OR, 3.40; P = 0.006). On multivariate analysis, O/E-LHR was predictive of the need for prosthetic patch repair, but not for GIM. FETO did not seem to affect the risk of GIM at 2 years.

CONCLUSION

In isolated left-sided CDH, fetal stomach position is the only factor that is predictive of GIM at 2 years of age. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Computed tomography based measurements to evaluate lung density and lung growth after congenital diaphragmatic hernia

Emphysema-like-change of lung is one aspect of lung morbidity in children after congenital diaphragmatic hernia (CDH). This study aims to evaluate if the extent of reduced lung density can be quantified through pediatric chest CT examinations, if side differences are present and if emphysema-like tissue is more prominent after CDH than in controls. Thirty-seven chest CT scans of CDH patients (mean age 4.5 ± 4.0 years) were analyzed semi-automatically and compared to an age-matched control group. Emphysema-like-change was defined as areas of lung density lower than - 950 HU in percentage (low attenuating volume, LAV). A p-value lower than 0.05 was regarded as statistically significant. Hypoattenuating lung tissue was more frequently present in the ipsilateral lung than the contralateral side (LAV 12.6% vs. 5.7%; p < 0.0001). While neither ipsilateral nor contralateral lung volume differed between CDH and control (p > 0.05), LAV in ipsilateral (p = 0.0002), but not in contralateral lung (p = 0.54), was higher in CDH than control. It is feasible to quantify emphysema-like-change in pediatric patients after CDH. In the ipsilateral lung, low-density areas are much more frequently present both in comparison to contralateral and to controls. Especially the ratio of LAV ipsilateral/contralateral seems promising as a quantitative parameter in the follow-up after CDH.

Quality of life was similar in children with congenital diaphragmatic hernia and oesophageal atresia and related to respiratory morbidity

AIM

To assess quality of life (QoL) in children with congenital diaphragmatic hernia (CDH) and to compare it with oesophageal atresia (OA).

METHODS

A cross-sectional study in CDH children (≥7 years) was conducted in Lille University Hospital, France, from January 2013 to April 2014. History, lung function (rest, exercise) and Pediatric Quality of Life Inventory questionnaires (PedsQoL 4.0) were collected. Data of OA children were previously published.

RESULTS

Fifty-four CDH patients (male: 53%, median age: 11 years, IQR 9-14) were compared to 54 OA patients (male: 61%, median age: 13 years, IQR: 11-15). CDH children had significantly more frequent history of pneumonia (30% vs 13%), exercise limitation (54% vs 35%) and chest deformity (39% vs 11%); 46% had an obstructive pattern and 66% an abnormal cardiopulmonary exercise test. The median PedsQoL total score in children was 81 (IQR 73-90) in CDH and 81 (IQR 72-91) in OA (P = .8). In CDH, duration of neonatal oxygen therapy, hospitalisation for respiratory disease, exercise limitation, inhaled corticosteroids treatment, chest deformity, abnormal cardiopulmonary exercise test and lower forced expiratory volume in one second were significantly associated with lower QoL scores.

CONCLUSION

PedsQoL scores remained satisfactory in CDH children with CDH, with no difference compared to OA. Patients with respiratory morbidity and lung function impairment, who displayed lower scores, should be identified in order to optimise their management in reference centres.

Impact of congenital diaphragmatic hernia on diaphragm muscle function in neonatal rats

Congenital diaphragmatic hernia (CDH) is characterized by incomplete partitioning of the thoracic and abdominal cavities by the diaphragm muscle (DIAm). The resulting in utero invasion of the abdominal viscera into the thoracic cavity leads to impaired fetal breathing movements, severe pulmonary hypoplasia, and pulmonary hypertension. We hypothesized that in a well-established rodent model of Nitrofen-induced CDH, DIAm isometric force generation, and DIAm fiber cross-sectional areas would be reduced compared with nonlesioned littermate and Control pups. In CDH and nonlesioned pups at embryonic day 21 or birth, DIAm isometric force responses to supramaximal field stimulation (200 mA, 0.5 ms duration pulses in 1-s duration trains at rates ranging from 10 to 100 Hz) was measured ex vivo. Further, DIAm fatigue was determined in response to 120 s of repetitive stimulation at 40 Hz in 330-ms duration trains repeated each second. The DIAm was then stretched to L_o, frozen, and fiber cross-sectional areas were measured in 10 μm transverse sections. In CDH pups, there was a marked reduction in DIAm-specific force and force following 120 s of fatiguing contraction. The cross-sectional area of DIAm fibers was also reduced in CDH pups compared with nonlesioned littermates and Control pups. These results show that CDH is associated with a dramatic weakening of the DIAm, which may contribute to poor survival despite various surgical efforts to repair the hernia and improve lung development.NEW & NOTEWORTHY There are notable respiratory deficits related to congenital diaphragmatic hernia (CDH), yet the contribution, if any, of frank diaphragm muscle weakness to CDH is unexplored. Here, we use the well-established Nitrofen teratogen model to induce CDH in rat pups, followed by diaphragm muscle contractility and morphological assessments. Our results show diaphragm muscle weakness in conjunction with reduced muscle fiber density and size, contributing to CDH morbidity.

Update on Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) is a rare developmental defect of the diaphragm, characterized by herniation of abdominal contents into the chest that results in varying degrees of pulmonary hypoplasia and pulmonary hypertension (PH). Significant advances in the prenatal diagnosis and identification of prognostic factors have resulted in the continued refinement of the approach to fetal therapies for CDH. Postnatally, protocolized approaches to lung-protective ventilation, nutrition, prevention of infection, and early aggressive management of PH have led to improved outcomes in infants with CDH. Advances in our understanding of the associated left ventricular (LV) hypoplasia and myocardial dysfunction in infants with severe CDH have allowed for the optimization of hemodynamics and management of PH. This article provides a comprehensive review of CDH for the anesthesiologist, focusing on the complex pathophysiology, advances in prenatal diagnosis, fetal interventions, and optimal postnatal management of CDH.

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

AIM

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

MATERIAL AND METHODS

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

RESULTS AND DISCUSSION

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

III Case series.

Human induced pluripotent stem cell-derived lung organoids in an ex vivo model of the congenital diaphragmatic hernia fetal lung

Three‐dimensional lung organoids (LOs) derived from pluripotent stem cells have the potential to enhance our understanding of disease mechanisms and to enable novel therapeutic approaches in neonates with pulmonary disorders. We established a reproducible ex vivo model of lung development using transgene‐free human induced pluripotent stem cells generated from fetuses and infants with Bochdalek congenital diaphragmatic hernia (CDH), a polygenic disorder associated with fetal lung compression and pulmonary hypoplasia at birth. Molecular and cellular comparisons of CDH LOs revealed impaired generation of NKX2.1⁺ progenitors, type II alveolar epithelial cells, and PDGFRα⁺ myofibroblasts. We then subjected these LOs to disease relevant mechanical cues through ex vivo compression and observed significant changes in genes associated with pulmonary progenitors, alveolar epithelial cells, and mesenchymal fibroblasts. Collectively, these data suggest both primary cell‐intrinsic and secondary mechanical causes of CDH lung hypoplasia and support the use of this stem cell‐based approach for disease modeling in CDH.

Respiratory Syncytial Virus Prophylaxis in Infants With Congenital Diaphragmatic Hernia in the Canadian Respiratory Syncytial Virus Evaluation Study of Palivizumab, 2005-2017

BACKGROUND

Infants with congenital diaphragmatic hernia (CDH) are at an increased risk of respiratory morbidity from recurrent respiratory tract infections including those from respiratory syncytial virus (RSV). Prospective studies on RSV prophylaxis in CDH infants are limited. We determined the risk of respiratory illness- and RSV-related hospitalizations (RIH and RSVH, respectively) among infants prophylaxed for CDH, standard indications (SIs) and those without increased risk (NR).

METHODS

The prospective Canadian Respiratory Syncytial Virus Evaluation Study of Palivizumab (CARESS) registry was searched for infants who received palivizumab during 12 RSV seasons (2005-2017) in Canada. Cox proportional hazards analyses were conducted to compare RIH and RSVH risks across the groups adjusted for potential confounders.

RESULTS

In total, 21 107 infants (201 CDH, 389 NR, and 20 517 SI) were included. RIH incidences were 10.0% (CDH), 2.1% (NR), and 6.2% (SI). CDH patients had a significantly higher RIH hazard compared with NR (hazard ratio [HR], 3.6 [95% confidence interval {CI}, 1.5-8.8]; P = .005) but not SI (HR, 1.2 [95% CI, .8-2.0]; P = .379). RSVH incidences were 0.6%, 0.3%, and 1.5% for CDH, NR, and SI, respectively. RSVH risk was similar across groups (SI: HR, 0.0, P = .922; NR: HR, 0.0, P = .934).

CONCLUSIONS

CDH infants had a 3-fold increased risk of RIH compared to NR but not SI infants. RSVH risk was similar with low RSVH incidences across all groups, implying that CDH infants may benefit from palivizumab during the RSV season, similar to other high-risk groups.

CLINICAL TRIALS REGISTRATION

NCT00420966.

Impact of a Multidisciplinary Craniofacial Clinic for Patients With Craniofacial Syndromes on Patient Satisfaction and Outcome

OBJECTIVE

Multidisciplinary clinics are becoming widely utilized. Given the number of patients with craniofacial syndromes evaluated at our institution, and the burden of assessment by multiple subspecialists, we created an American Cleft Palate-Craniofacial Association-certified Craniofacial Multidisciplinary Clinic (CMC) composed of a nurse practitioner, neurosurgeon, plastic surgeon, otolaryngologist, oromaxillofacial surgeon, geneticist, pulmonologist, occupational therapist, dentist, and child life specialist to improve patient experience, lessen the burden of assessment, decrease time to surgery, and improve patients' understanding of the diagnosis and treatment plan specifically for patients with complex craniofacial syndromes. We reviewed the impact of this clinic after 1 year of implementation.

DESIGN

Retrospective review was performed to identify patients with craniofacial syndromic diagnoses seen by the neurosurgery department before and after implementation of the CMC from February 2017 to present.

SETTING

The CMC is an outpatient clinic based in a tertiary care academic institution.

PATIENTS

Chart review was performed to identify demographic, diagnostic, clinical, and treatment data. We assessed clinic experience, and the impact on quality of clinical and surgical care was assessed via survey. We compared this cohort to patients with similar craniofacial syndromes treated prior to the CMC. Thirty patients seen at the CMC were identified, and data from a comparable cohort of 30 patients seen prior to the clinic's inception was reviewed.

RESULTS

Our CMC survey response rate was 67% (n = 20/30) for the CMC patients. Second opinions sought by parents prior to CMC was higher (mean = 0.85, range: 0-3) than for patients seen at the CMC (mean = 0.16, range: 0-1). Mean time to surgery before the CMC was 10.1 months (range: 1-15) compared to 4 months (range: 3-5) after implementation. Parents agreed that they felt well-informed about their diagnosis (n = 18/20, 90%), and that the presence of a plastic surgeon (19/20, 95%) and a nurse practitioner (17/20, 85%) were valuable in coordination of their care. Following surgery, 76% (n = 13/17) of patients who received surgery were happy with the outcome, 76% (n = 13/17) were happy with the appearance of the scar, and 95% (n = 19/20) would recommend the CMC to others.

CONCLUSION

Multidisciplinary evaluation of patients with complex craniofacial conditions provides comprehensive, efficient, and effective care, as well as improved parent satisfaction and knowledge base.

Longitudinal Analysis of Ventilation Perfusion Mismatch in Congenital Diaphragmatic Hernia Survivors

OBJECTIVE

To determine the natural history of pulmonary function for survivors of congenital diaphragmatic hernia (CDH).

STUDY DESIGN

This was a retrospective cohort study of survivors of CDH born during 1991-2016 and followed at our institution. A generalized linear model was fitted to assess the longitudinal trends of ventilation (V), perfusion (Q), and V/Q mismatch. The association between V/Q ratio and body mass index percentile as well as functional status was also assessed with a generalized linear model.

RESULTS

During the study period, 212 patients had at least one V/Q study. The average ipsilateral V/Q of the cohort increased over time (P < .01), an effect driven by progressive reduction in relative perfusion (P = .012). A higher V/Q ratio was correlated with lower body mass index percentile (P < .001) and higher probability of poor functional status (New York Heart Association class III or IV) (P = .045).

CONCLUSIONS

In this cohort of survivors of CDH with more severe disease characteristics, V/Q mismatch worsens over time, primarily because of progressive perfusion deficit of the ipsilateral side. V/Q scans may be useful in identifying patients with CDH who are at risk for poor growth and functional status.

Chest CT scoring for evaluation of lung sequelae in congenital diaphragmatic hernia survivors

OBJECTIVES

Data on long-term structural lung abnormalities in survivors of congenital diaphragmatic hernia (CDH) is scarce. The purpose of this study was to develop a chest computed tomography (CT) score to assess the structural lung sequelae in CDH survivors and to study the correlation between the CT scoring and clinical parameters in the neonatal period and at 1 year of follow-up.

METHODS

A prospective, clinical follow-up program is organised for CDH survivors at the University Hospital of Leuven including a chest CT at the age of 1 year. The CT scoring used and evaluated, named CDH-CT score, was adapted from the revised Aukland score for chronic lung disease of prematurity.

RESULTS

Thirty-five patients were included. All CT scans showed some pulmonary abnormalities, ranging from very mild to severe. The mean total CT score was 16 (IQR: 9-23), with the greatest contribution from the subscores for decreased attenuation (5; IQR: 2-8), subpleural linear and triangular opacities (4; IQR: 3-5), and atelectasis/consolidation (2; IQR: 1-3). Interobserver and intraobserver agreement was very good for the total score (ICC coefficient > 0.9). Total CT score correlated with number of neonatal days ventilated/on oxygen as well as with respiratory symptoms and feeding problems at 1 year of age.

CONCLUSION

The CDH-CT scoring tool has a good intraobserver and interobserver repeatability and correlates with relevant clinical parameters. This holds promise for its use in clinical follow-up and as outcome parameter in clinical interventional studies.

Long-term feeding issue and its impact on the daily life of congenital diaphragmatic hernia survivors: results of the first patient-led survey

BACKGROUND

CDH UK is a registered charity governed by a volunteer committee and providing informal support to patients, families and healthcare workers affected directly or indirectly with congenital diaphragmatic hernia (CDH) internationally. This is the first patient-led survey undertaken by CDH UK aiming for highlighting the feeding problems and their impact on the daily life of CDH survivors.

METHODS

Answers from CDH survivors were collected through an online questionnaire (SurveyMonkey^®) undertaken by CDH UK. The questionnaire contained questions about their feeding problems and support they were receiving for it.

MAIN RESULTS

Overall, 151 patients answered some parts of the survey and 102 patients completed the questionnaire. Overall, 116 (76.8%) responders reported suffering from any type of feeding issue. Gastric acid reflux (GER) and growth retardation were the commonest symptoms experienced by 97 (91.5%) and 72 (62.2%) responders, respectively. Only 18 (17.0%) responders have received any written information on feeding or details of patient/parent support. Eighty (75.5%) responders are satisfied with the level of support they are receiving, but 78 (76.4%) answered that the whole experience associated with the disease has been very or extremely stressful.

CONCLUSIONS

CDH survivors frequently have various issues with feeding, which may not be adequately supported or discussed clinically. It is desirable to assist the patients to reliable resources of long-term support, including multidisciplinary team (MDT) approach.

Short-term respiratory outcomes of neonates with symptomatic congenital lung malformations

INTRODUCTION

The purpose of this study was to evaluate short-term respiratory outcomes in neonates with symptomatic congenital lung malformations (CLM).

METHODS

Consecutive newborns who underwent surgical resection of a CLM were retrospectively reviewed. Demographic, prenatal, and outcomes data were analyzed as appropriate (p < 0.05).

RESULTS

Twenty-one neonates were managed at a median gestational age of 36.2 weeks [interquartile range (IQR), 33.8-39.0]. Endotracheal intubation was required in 14 (66.7%) for a median of 7.5 days [interquartile range (IQR), 3.0-25.8]. Three (14.3%) children underwent ex utero intrapartum treatment-to-resection, and another 14 (66.7%) had neonatal lung resections performed at a median age of 2.0 days (IQR, 0.08-19.5 days). Excluding one patient who received comfort care at birth, all neonates survived to hospital discharge with a median length of hospitalization of 36.5 days (IQR, 23.8-56.5). More than one-quarter were discharged on supplemental oxygen by nasal cannula. Based on a median follow up of 35.5 months (IQR, 19.0-80.8), CLM-related morbidity was still evident in 55.0%.

CONCLUSION

Our study suggests a high incidence of complications and chronic respiratory morbidity after neonatal lung resection for symptomatic CLMs. These data highlight the need to provide realistic expectations in perinatal counseling discussions with families and the importance of coordinating appropriate multidisciplinary follow up for these children.

LEVEL OF EVIDENCE

Level IV.

Long-term medical and psychosocial outcomes in congenital diaphragmatic hernia survivors

OBJECTIVE

Survival rates for congenital diaphragmatic hernia (CDH) are increasing. The long-term outcomes of CDH survivors were compared with a healthy control group to assess the morbidity for guidance of antenatal counselling and long-term follow-up programmes.

PARTICIPANTS AND DESIGN

Participants born with CDH in Western Australia 1993-2008 were eligible with matched controls from the general population. Participants had comprehensive lung function tests, echocardiogram, low-dose chest CT scan and completed a Strengths and Difficulties Questionnaire (SDQ) and quality of life (QOL) questionnaire.

RESULTS

34 matched case-control pairs were recruited. Demographic data between groups were similar. Cases were smaller at follow-up (weight Z-score of -0.2vs0.3; p=0.03; height Z-score of -0.3vs0.6; p=0.01). Cases had lower mean Z-scores for forced expiratory volume in 1 s (FEV₁) (-1.49 vs -0.01; p=0.004), FEV₁/forced vital capacity (-1.92 vs -1.2; p=0.009) and forced expiratory flow at 25-75% (FEF25-75) (-1.18vs0.23; p=0.007). Cases had significantly worse respiratory mechanics using forced oscillation technique. Subpleural triangles architectural distortion, linear opacities and scoliosis on chest CT were significantly higher in cases. Prosthetic patch requirement was associated with worse lung mechanics and peak cough flow. Cases had significantly higher rates of gastro-oesophageal reflux disease (GORD) and GORD medication usage. Developmental delay was significantly higher in cases. More cases had a total difficulties score in the high to very high range (25% vs 0%, p=0.03) on the SDQ and reported lower objective QOL scores (70.2 vs 79.8, p=0.02).

CONCLUSION

Survivors of CDH may have significant adverse long-term medical and psychosocial issues that would be better recognised and managed in a multidisciplinary clinic.

[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.

Resting energy expenditure in infants with congenital diaphragmatic hernia without respiratory support at time of neonatal hospital discharge

BACKGROUND

Infants with congenital diaphragmatic hernia (CDH) are at risk for growth failure because of inadequate caloric intake and high catabolic stress. There is limited data on resting energy expenditure (REE) in infants with CDH.

AIMS

To assess REE via indirect calorimetry (IC) in term infants with CDH who are no longer on respiratory support and nearing hospital discharge with advancing post-conceptional age and to assess measured-to-predicted REE using predictive equations.

METHODS

A prospective cohort study of term infants with CDH who were no longer on respiratory support and nearing hospital discharge was conducted to assess REE via IC and caloric intake. Baseline characteristics and hospital course data were collected. Three day average caloric intake around time of IC testing was calculated. Change in REE with advancing post-conceptional age and advancing post-natal age was assessed. The average measured-to-predicted REE was calculated for the cohort using predictive equations [22].

RESULTS

Eighteen infants with CDH underwent IC. REE in infants with CDH increased with advancing postconceptional age (r2 = 0.3, p < 0.02). The mean REE for the entire group was 53.2 +/- 10.9 kcal/kg/day while the mean caloric intake was 101.2 +/- 17.4 kcal/kg/day. The mean measured-to-predicted ratio for the cohort was in the normal metabolic range (1.10 +/- 0.17) with 50% of infants considered hypermetabolic and 11% of infants considered hypo-metabolic.

CONCLUSIONS

Infant survivors of CDH repair who are without respiratory support at time of neonatal hospital discharge have REE, as measured by indirect calorimetry, that increases with advancing post-conceptional age and that is within the normal metabolic range when compared to predictive equations.

LEVEL OF EVIDENCE

III.

Upregulated EFNB2 and EPHB4 promotes lung development in a nitrofen-induced congenital diaphragmatic hernia rat model

Congenital diaphragmatic hernia (CDH) is a common congenital malformation associated with high mortality rates, mainly due to pulmonary hypoplasia and persistent pulmonary hypertension following birth. The present study aimed to investigate abnormal lung development in a rat CDH model, and examine temporal and spatial changes in the expression of ephrin type‑B receptor 4 (EPHB4) and ephrin‑B2 (EFNB2) during fetal lung development, to elucidate the role of these factors during lung morphogenesis. Pregnant rats received nitrofen on embryonic day (E) 8.5 to induce CDH, and fetal lungs were collected on E13.5, E15.5, E17.5, E19.5, and E21.5. The mean linear intercept (MLI) and mean alveolar number (MAN) were observed in fetal lung tissue at E21.5 following hematoxylin and eosin staining. E13.5 fetal lungs were cultured for 96 h in serum‑free medium and branch development was observed under a microscope. The gene and protein expression levels of EPHB4 and EFNB2 were assessed by reverse transcription‑quantitative polymerase chain reaction analysis, and immunoblotting and immunohistochemistry, respectively. The fetal rat lungs were treated with EFNB2 and the activity of key signaling pathways was assessed. The lung index (lung weight/body weight) at E21.5 was significantly lower in the CDH rats, compared with that in the control fetal rats. The MLI and MAN were also lower in the CDH group. The number of lung terminal buds at E13.5 (embryonic stage), and the lung‑explant perimeter and surface were all smaller in the CDH group rats than in the control group at the same age. Pulmonary hypoplasia was observed following 96 h of in vitro culture. No significant differences were found in the expression levels of EFNB2 and EPHB4 between the CDH and control groups at E13.5 (embryonic stage) or E15.5 (pseudoglandular stage), however, EFNB2 and EPHB4 were significantly upregulated at E17.5 (canalicular stage), and at E19.5 and E21.5 (saccular/alveolar stages). EFNB2 stimulated pulmonary branching and EFNB2 supplementation decreased the activity of p38, c‑Jun NH2‑terminal kinase, extracellular signal‑regulated kinase, and signal transducer and activator of transcription. The CDH fetal rats developed pulmonary dysplasia at an early stage of fetal pulmonary development. Upregulated expression of EFNB2 and EPHB4 was observed in the rat lung of nitrofen‑induced CDH, and the increased expression of EFNB2 promoted rat lung development in the nitrofen‑induced CDH model.

Respiratory syncytial virus prophylaxis and the "special population"

Bronchiolitis is the most frequent airway infection in the first 2 years of life, and the respiratory syncytial virus (RSV) is the most frequently responsible virus. In selected high-risk groups, RSV may cause severe respiratory disease leading to hospitalization, need for mechanical ventilation, and even death. These high-risk groups include children with congenital heart disease, infants with neuromuscular impairment, cystic fibrosis, Down Syndrome, immunodeficiency syndromes and others specific conditions. In these high-risk populations defined in literature as "special population", a 3- to 10-fold increase in the rate of RSV hospitalization has been observed, justifying RSV specific prophylaxis with palivizumab, a monoclonal antibody that binds a viral glycoprotein epitope and blocks the link between RSV and target cell. Evidence of safety and efficacy of RSV prophylaxis in these populations is lacking. Given the low incidence of these conditions, randomized clinical trials are not feasible. The purpose of this paper is to give an update from the literature of various conditions at higher risk to develop severe RSV infection, and to offer an overview of the efficacy of palivizumab in preventing RSV infection in these specific populations.

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.

Circulating microRNAs are associated with Pulmonary Hypertension and Development of Chronic Lung Disease in Congenital Diaphragmatic Hernia

Pulmonary hypertension (PH) contributes to high mortality in congenital diaphragmatic hernia (CDH). A better understanding of the regulatory mechanisms underlying the pathology in CDH might allow the identification of prognostic biomarkers and potential therapeutic targets. We report the results from an expression profiling of circulating microRNAs (miRNAs) in direct post-pulmonary blood flow of 18 CDH newborns. Seven miRNAs differentially expressed in children that either died or developed chronic lung disease (CLD) up to 28 days after birth, compared to those who survived without developing CLD during this period, were identified. Target gene and pathway analyses indicate that these miRNAs functions include regulation of the cell cycle, inflammation and morphogenesis, by targeting molecules responsive to growth factors, cytokines and cellular stressors. Furthermore, we identified hub molecules by constructing a protein-protein interaction network of shared targets, and ranked the relative importance of the identified miRNAs. Our results suggest that dysregulations in miRNAs let-7b-5p, -7c-5p, miR-1307-3p, -185-3p, -8084, -331-3p and -210-3p may be detrimental for the development and function of the lungs and pulmonary vasculature, compromise cardiac function and contribute to the development of CLD in CDH. Further investigation of the biomarker and therapeutic potential of these circulating miRNAs is encouraged.

Fetal lung transcriptome patterns in an ex vivo compression model of diaphragmatic hernia

BACKGROUND

The purpose of this study was to employ a novel ex vivo lung model of congenital diaphragmatic hernia (CDH) to determine how a mechanical compression affects early pulmonary development.

METHODS

Day-15 whole fetal rat lungs (n = 6-12/group) from nitrofen-exposed and normal (vehicle only) dams were explanted and cultured ex vivo in compression microdevices (0.2 or 0.4 kPa) for 16 h to mimic physiologic compression forces that occur in CDH in vivo. Lungs were evaluated with significance set at P < 0.05.

RESULTS

Nitrofen-exposed lungs were hypoplastic and expressed lower levels of surfactant protein C at baseline. Although compression alone did not alter the α-smooth muscle actin (ACTA2) expression in normal lungs, nitrofen-exposed lungs had significantly increased ACTA2 transcripts (0.2 kPa: 2.04 ± 0.15; 0.4 kPa: 2.22 ± 0.11; both P < 0.001). Nitrofen-exposed lungs also showed further reductions in surfactant protein C expression at 0.2 and 0.4 kPa (0.53 ± 0.04, P < 0.01; 0.69 ± 0.23, P < 0.001; respectively). Whereas normal lungs exposed to 0.2 and 0.4 kPa showed significant increases in periostin (POSTN), a mechanical stress-response molecule (1.79 ± 0.10 and 2.12 ± 0.39, respectively; both P < 0.001), nitrofen-exposed lungs had a significant decrease in POSTN expression (0.4 kPa: 0.67 ± 0.15, P < 0.001), which was confirmed by immunohistochemistry.

CONCLUSIONS

Collectively, these pilot data in a model of CDH lung hypoplasia suggest a primary aberration in response to mechanical stress within the nitrofen lung, characterized by an upregulation of ACTA2 and a downregulation in SPFTC and POSTN. This ex vivo compression system may serve as a novel research platform to better understand the mechanobiology and complex regulation of matricellular dynamics during CDH fetal lung development.

Milrinone in congenital diaphragmatic hernia - a randomized pilot trial: study protocol, review of literature and survey of current practices

Background

Congenital diaphragmatic hernia (CDH) is commonly associated with pulmonary hypoplasia and pulmonary hypertension (PH). PH associated with CDH (CDH-PH) is frequently resistant to conventional pulmonary vasodilator therapy including inhaled nitric oxide (iNO) possibly due to right and left ventricular dysfunction. Milrinone is an intravenous inotrope and lusitrope with pulmonary vasodilator properties and has been shown anecdotally to improve oxygenation in PH. We developed this pilot study to determine if milrinone infusion would improve oxygenation in neonates ≥36 weeks postmenstrual age (PMA) with CDH.

Methods/design

Data on pulmonary vasodilator management and outcome of CDH patients was collected from 18 university NICUs affiliated with the Neonatal Research Network (NRN) from 2011 to 2012. The proposed pilot will be a masked, placebo–controlled, multicenter, randomized trial of 66 infants with CDH with an oxygenation index (OI) ≥10 or oxygen saturation index (OSI) ≥5. The primary outcome is the oxygenation response, as determined by change in OI at 24 h after initiation of study drug. As secondary outcomes, we will determine oxygenation at 48 h and 72 h post-infusion, right ventricular pressures on echocardiogram and the incidence of systemic hypotension, arrhythmias, intracranial hemorrhage, survival without extracorporeal membrane oxygenation, and chronic lung disease (oxygen need at 28 days postnatal age). Finally, we will evaluate the pulmonary and nutritional status at 4, 8 and 12 months of age using a phone questionnaire.

Results

Three hundred thirty-seven infants with CDH were admitted to NRN NICUs in 2011 and 2012 of which 275 were ≥36 weeks PMA and were exposed to the following pulmonary vasodilators: iNO (39%), sildenafil (17%), milrinone (17%), inhaled epoprostenol (6%), intravenous epoprostenol (3%), and intravenous PGE1 (1%). ECMO was required in 36% of patients. Survival to discharge was 71%.

Discussion

CDH is an orphan disease with high mortality with few randomized trials evaluating postnatal management. Intravenous milrinone is a commonly used medication in neonatal/pediatric intensive care units and is currently used in 17% of patients with CDH within the NRN. This pilot study will provide data and enable further studies evaluating pulmonary vasodilator therapy in CDH.

Trial registration

ClinicalTrials.gov; NCT02951130; registered 14 October 2016.

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.

Congenital Diaphragmatic hernia - a review

Congenital Diaphragmatic hernia (CDH) is a condition characterized by a defect in the diaphragm leading to protrusion of abdominal contents into the thoracic cavity interfering with normal development of the lungs. The defect may range from a small aperture in the posterior muscle rim to complete absence of diaphragm.

The pathophysiology of CDH is a combination of lung hypoplasia and immaturity associated with persistent pulmonary hypertension of newborn (PPHN) and cardiac dysfunction. Prenatal assessment of lung to head ratio (LHR) and position of the liver by ultrasound are used to diagnose and predict outcomes. Delivery of infants with CDH is recommended close to term gestation. Immediate management at birth includes bowel decompression, avoidance of mask ventilation and endotracheal tube placement if required. The main focus of management includes gentle ventilation, hemodynamic monitoring and treatment of pulmonary hypertension followed by surgery. Although inhaled nitric oxide is not approved by FDA for the treatment of PPHN induced by CDH, it is commonly used.

Extracorporeal membrane oxygenation (ECMO) is typically considered after failure of conventional medical management for infants ≥ 34 weeks’ gestation or with weight >2 kg with CDH and no associated major lethal anomalies. Multiple factors such as prematurity, associated abnormalities, severity of PPHN, type of repair and need for ECMO can affect the survival of an infant with CDH. With advances in the management of CDH, the overall survival has improved and has been reported to be 70-90% in non-ECMO infants and up to 50% in infants who undergo ECMO.

Does the ex utero intrapartum treatment to extracorporeal membrane oxygenation procedure change morbidity outcomes for high-risk congenital diaphragmatic hernia survivors?

PURPOSE

In high-risk congenital diaphragmatic hernia (CDH), significant barotrauma or death can occur before extracorporeal membrane oxygenation (ECMO) can be initiated. We previously examined ex utero intrapartum treatment (EXIT)-to-ECMO in our most severe CDH patients, but demonstrated no survival advantage. We now report morbidity outcomes in survivors of this high-risk cohort to determine whether EXIT-to-ECMO conferred any benefit.

METHODS

All CDH survivors with <15% predicted lung volume (PPLV) from September 1999 to December 2010 were included. We recorded prenatal imaging, defect size, and pulmonary, nutritional, cardiac, and neurodevelopmental outcomes.

RESULTS

Seventeen survivors (8 EXIT-to-ECMO, 9 non-EXIT) had an average PPLV of 11.7%. Eight of 9 non-EXIT received ECMO within 2days. There were no significant defect size differences between groups, mostly left-sided (13/17) and type D (12/17). Average follow-up was 6.7years (0-13years). There were no statistically significant differences in outcomes, including supplemental oxygen, diuretics, gastrostomy, weight-for-age Z scores, fundoplication, pulmonary hypertension, stroke or intracranial hemorrhage rate, CDH recurrence, and reoperation. No survivor in our cohort was neurologically devastated. All had mild motor and/or speech delay, which improved in most.

CONCLUSIONS

In this pilot series of severe CDH survivors, EXIT-to-ECMO confers neither significant survival nor long-term morbidity benefit.

LEVEL OF EVIDENCE

Level III treatment study.

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.

Risk of Readmission for Wheezing during Infancy in Children with Congenital Diaphragmatic Hernia

RATIONALE

Congenital diaphragmatic hernia (CDH) is associated with a high incidence of respiratory problems, even after initial hospital discharge. These problems are likely to lead to re-hospitalization during infancy, although actual frequency of readmissions is unknown.

OBJECTIVE

We aimed to determine the rate of hospitalization for wheezing in infants with CDH between the time of initial discharge and 24 months of age, and to identify factors associated with readmission.

METHODS

Data about infants with CDH born in three French reference tertiary centers between January 2009 and March 2013 who were alive at hospital discharge, were extracted from a prospective national database.

RESULTS

Ninety-two children were identified, and 86 were included in the analysis. In total, 116 wheezing episodes requiring a doctor's visit occurred in 50 infants (58%) before 24 months of age. Twenty-two children (26%) were readmitted at least once for wheezing exacerbations. RSV was present in 6 of 15 (40%) of children with available nasal samples at first readmission, and 1 of 5 (20%) at second readmission. Thoracic herniation of the liver, low gestational age, longer initial hospitalization, need for oxygen therapy at home, and eczema were all significantly associated with readmission for wheezing exacerbations. Fifty-three infants (62%) received palivizumab prophylaxis, but there was no association with the overall rate of readmission for wheezing exacerbations or RSV-related hospitalization.

CONCLUSIONS

The rate of readmission for wheezing among infants with CDH is high, and significantly influenced by several prenatal and neonatal factors. Palivizumab prophylaxis was not associated with the rate of readmission.

Congenital diaphragmatic hernia: Observed/expected lung-to-head ratio as a predictor of long-term morbidity

AIM

The aim of this study was to investigate the association of observed/expected (O/E) lung-to-head ratio (LHR) with long-term morbidity for isolated fetal congenital diaphragmatic hernia (CDH) patients in a single institution.

METHODS

We performed a retrospective study of prenatally diagnosed CDH from 18 to 38weeks of gestation (01/2002-04/2010). Two cohorts of O/E LHR were defined (22.6-45%, 45.1-78.3%) based upon previous studies. Survivors with at least 1-year follow-up of prospectively collected long-term morbidity assessments were included.

RESULTS

O/E LHR was available in 43 survivors (median 40%, range 22.8-78.3%). Follow-up data were available in 41 survivors (M:F=24:17, left CDH=39/41). Median follow-up was 6.5years (1-11years). Height/weight trajectories were similar between the two cohorts, with the majority below the 50th centile. There were no differences between the two cohorts by age 3years for Bayley scales (developmental domains) and/or REEL-3 (language development). In addition, V/Q scans in the two cohorts demonstrated similar degrees of mismatch (mean delta V/Q=35.4 versus 31.3).

CONCLUSIONS

In fetuses with isolated CDH, a reduction in O/E LHR does not predict a worse outcome in long-term follow-up. There is no association between a lower O/E LHR and a reduction in REEL-3 or Bayley score nor V/Q mismatch.

Congenital diaphragmatic hernia, management in the newborn

Congenital diaphragmatic hernia (CDH) in the newborn poses challenges to the multi-disciplinary teams involved in its management. Mortality remains significantly high, despite growing understanding and treatment options. Early intubation of antenatally diagnosed cases is crucial in preventing deterioration and persistent pulmonary hypertension. Early recognition of cases not diagnosed on antenatal scan, with appreciation of differential diagnosis, requires an index of suspicion and imaging. Increasing options and modalities are available, with only modest, if any, survival advantage. Permissive hypercapnea and minimal ventilation have made the most significant impact on survival in modern era. High-frequency oscillatory ventilation (HFOV), inhaled nitric oxide (iNO), treatment of pulmonary hypertension, and ECMO are used in a somewhat stepwise manner for stabilisation. Delayed surgery has become established later in management plan. The impact of individual therapies (e.g. HFOV, iNO, ECMO) on outcome is difficult to ascertain. Little level 1 or 2 evidence exists. Randomised studies and reviews on the role of ECMO have not yet proven any long-term survival benefit. One pilot randomised study of thoracoscopic repair suggests increased acidosis; intraoperative blood gases and CO2 levels should be closely monitored. Monitoring tissue oxygenation should be considered. There is no evidence to suggest the best patch material.

Lung function over the first 3 years of life in children with congenital diaphragmatic hernia

OBJECTIVES

Infants with congenital diaphragmatic hernia (CDH) have variable degrees of pulmonary hypoplasia at birth. Few reports of lung function over the first years of life exist in this group of children.

HYPOTHESIS

Pulmonary function abnormalities correlate with severity of neonatal disease and intensity of neonatal therapies needed. We also hypothesized that longitudinal measurements of lung function over the usual period of rapid lung growth would lend some insight into how the lung remodels in CDH infants.

METHODOLOGY

Ninety-eight infants with CDH between 11 days and 44 months of age underwent pulmonary function testing (PFT) on 1-5 occasions using the raised volume rapid thoracic compression technique. Demographic data were also collected.

MAIN RESULTS

Forced expiratory flows were below normal. Total lung capacity was normal, but residual volume and functional residual capacity were elevated. Children requiring patch closure, ECMO, or pulmonary vasodilators generally had lower lung functions at follow up. Additionally, longer duration of mechanical ventilation correlated with worse lung function.

CONCLUSIONS

Lung functions of survivors of CDH remain abnormal throughout the first 3 years of life. The degree of pulmonary function impairment correlated both with markers of the initial degree of pulmonary hypoplasia and the duration of mechanical ventilation. Understanding the relationship between the phenotypic presentation of CDH and the potential for subsequent lung growth could help refine both pre- and postnatal therapies to optimize lung growth in CDH infants.

An association between pulmonary hypertension and impaired lung function in infants with congenital diaphragmatic hernia

RATIONALE

Infants with congenital diaphragmatic hernia (CDH) can develop pulmonary hypertension (PH) from decreased number and abnormal muscularization of pulmonary arteries. Normally pulmonary vascular growth and remodeling parallel airspace growth and alveolarization, which exhibits a wide morphologic variation in CDH.

AIM

To assess whether infants with CDH and PH have greater abnormalities in infant pulmonary function testing (IPFT) compared to those without PH.

METHODS

We reviewed results of IPFTs and echocardiograms performed on infants with CDH from 2004 to June 2011. Lung volumes, forced flows and tidal mechanics were standardized according to available reference values. Comparisons between infants with and without PH were performed using linear regression, adjusting for potential confounders.

MAIN RESULTS

Sixty-six infants were included; 18 had PH and 48 did not. Z-score values for functional residual capacity (FRC), residual volume (RV), FRC/total lung capacity (TLC), and RV/TLC were significantly higher in infants with CDH and PH compared to those without PH. Z-score values for forced flows including forced expiratory volume in the first 0.5 sec (FEV0.5) and FEV0.5/forced vital capacity were significantly lower in infants with CDH and PH compared to those without PH. For 29 infants studied on ≥2 occasions, the slopes of FRC, RV, and TLC versus length were significantly higher in those with persistent PH compared to those without.

CONCLUSIONS

Infants with CDH and persistent PH demonstrate greater airspace overdistension with growth compared to those without. Therapies that modify disrupted pulmonary vascular and alveolar formation could potentially improve future care of these patients.

Management Practice and Mortality for Infants with Congenital Diaphragmatic Hernia

OBJECTIVE

Congenital diaphragmatic hernia (CDH) is fatal in 20 to 40% of cases, largely due to pulmonary dysmaturity, lung hypoplasia, and persistent pulmonary hypertension. Evidence for survival benefit of inhaled nitric oxide (iNO), extracorporeal membrane oxygenation (ECMO), and other medical interventions targeting pulmonary hypertension is lacking. We assessed medical interventions and mortality over time in a large multicenter cohort of infants with CDH.

STUDY DESIGN

We identified all infants ≥ 34 weeks' gestation with CDH discharged from 29 neonatal intensive care units between 1999 and 2012 with an average of ≥ 2 CDH admissions per year. We examined mortality and the proportion of infants exposed to medical interventions, comparing four periods of time: 1999-2001, 2002-2004, 2005-2007, and 2008-2012.

RESULTS

We identified 760 infants with CDH. From 1999-2001 to 2008-2012, use of iNO increased from 20% of infants to 50%, sildenafil use increased from 0 to 14%, and milrinone use increased from 0 to 22% (p < 0.001). Overall mortality (28%) did not significantly change over time compared with the earliest time period.

CONCLUSION

Despite changing use of iNO, sildenafil, and milrinone, CDH mortality has not significantly decreased in this population of infants.

Pulmonary support on day of life 30 is a strong predictor of increased 1 and 5-year morbidity in survivors of congenital diaphragmatic hernia

PURPOSE

Pulmonary support (PS) on day-of-life-30 (DOL-30) has been shown to be the strongest predictor of subsequent morbidity and in-patient mortality in congenital diaphragmatic hernia (CDH). We hypothesized that PS on DOL-30 can also predict long-term outcomes in CDH survivors.

METHODS

We analyzed records of 201 CDH survivors followed by a single multidisciplinary clinic (1995-2010). Follow-up was 83 and 70% at 1 and 5years respectively. PS was defined as: (1) invasive support (n=44), (2) noninvasive support (n=54), or (3) room air (n=103). Logistic regression was used to estimate the adjusted association of PS on DOL-30 with outcomes at 1 and 5-years.

RESULTS

Use of PS on DOL-30 was significantly associated with pulmonary and developmental morbidities at 1 and 5-years. Even after adjusting for defect-size and presence of ventilation/perfusion mismatch, greater PS on DOL-30 was associated with a significantly increased odds of requiring supplemental oxygen and developmental referral at 1-year, and asthma and developmental referral at 5-years.

CONCLUSION

CDH survivors continue to have significant long-term pulmonary and developmental morbidities. PS on DOL-30 is a strong independent predictor of morbidity at 1 and 5-years and may be used as a simple prognostic tool to identify high-risk infants.

Respiratory muscle strength in healthy infants and those with surgically correctable anomalies

Assessment of respiratory muscle strength provides important diagnostic and prognostic information. Normative data in healthy, term infants is, however, limited. Surgically correctable birth defects, congenital diaphragmatic hernia (CDH) and abdominal wall defects (AWD), commonly have impaired diaphragm function. The study aims were to obtain normative data for respiratory muscle strength in healthy, term born infants at birth and at 6 weeks postnatal age (PNA) and to investigate the influence of growth and maturation on inspiratory muscle strength in CDH/AWD infants. Maximal inspiratory (cPimax) and expiratory (cPemax) pressures during crying were measured at birth in 67 healthy, term born infants (mean (SD) gestational age (GA) 39.4 (1.7) weeks) and reassessed in 27 at 6 weeks PNA. cPimax and functional residual capacity (FRC) (22.3 (4.2) ml/kg) were also measured in 23 infants with AWD/CDH (mean (SD) GA 36.9 (2.1) weeks) and reassessed in 16 at median (range) 6.5 (1.5-15) months PNA. In healthy infants, mean (SD) cPimax was 88.8 (19.33) cmH2 O and cPemax 61.8 (13.5) cmH2 O at birth, increasing significantly at followup to 100.9 (15.2) cmH2 O (P < 0.05) and 82.6 (19.4) cmH2 O (P < 0.001) respectively. Mean (SD) cPimax was significantly lower (47.5 (22.4) cmH2 O, P < 0.0001) in AWD/CDH infants compared to healthy infants at birth but had increased significantly to 88.1 (27.6) cmH2 O (P < 0.0001) at followup which correlated significantly with increases in FRC (r(2)  = 0.33, P = 0.0263). Infants with AWD and CDH have significantly reduced inspiratory muscle strength compared to healthy term born infants but strength increases markedly in early life.

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).

Histologic identification of prominent intrapulmonary anastomotic vessels in severe congenital diaphragmatic hernia

OBJECTIVE

To determine whether prominent intrapulmonary anastomotic vessels (IPAVs) or bronchopulmonary "shunt" vessels can be identified in lungs from infants with fatal congenital diaphragmatic hernia (CDH).

STUDY DESIGN

We performed histology with immunostaining for CD31 (endothelium) and D2-40 (lymphatics), along with high-precision 3-dimensional (3D) reconstruction on lung tissue from 9 patients who died with CDH.

RESULTS

Each patient with CDH required mechanical ventilation, cardiotonic support, and pulmonary hypertension (PH)-targeted drug therapy. All patients were diagnosed with severe PH by echocardiography, and 5 received extracorporeal membrane oxygenation therapy. Death occurred at a median age of 24 days (range, 10-150 days) from refractory hypoxemia with severe PH, pneumonia, or tension pneumothorax. Histology showed decreased alveolarization with pulmonary vascular disease. In each patient, prominent IPAVs were identified as engorged, thin-walled vessels that connected pulmonary veins with microvessels surrounding pulmonary arteries and airways in lungs ipsilateral and contralateral to the CDH. Prominent anastomoses between pulmonary arteries and bronchial arteries were noted as well. The 3D reconstruction studies demonstrated that IPAVs connect pulmonary vasculature to systemic (bronchial) vessels both at the arterial and venous side.

CONCLUSION

Histology and 3D reconstruction identified prominent bronchopulmonary vascular anastamoses in the lungs of infants who died with severe CDH. We speculate that IPAVs connecting pulmonary and bronchial arteries contribute to refractory hypoxemia in severe CDH.