Diaphragmatic Defects in Infants: Acute Management and Repair.

Congenital diaphragmatic hernia (CDH) is a complex and highly variable disease process that should be treated at institutions with multidisciplinary teams designed for their care. Treatment in the neonatal period focuses on pulmonary hypoplasia, pulmonary hypertension, and cardiac dysfunction. Extracorporeal membrane oxygenation (ECMO) can be considered in patients refractory to medical management. Repair of CDH early during the ECMO course seems to improve mortality compared with other times for surgical intervention. The choice of surgical approach to CDH repair should consider the patient's physiologic status and the surgeon's familiarity with the operative approaches available, recognizing the pros/cons of each technique.

A clinical consensus guideline for nutrition in infants with congenital diaphragmatic hernia from birth through discharge.

OBJECTIVE: To develop a consensus guideline to meet nutritional challenges faced by infants with congenital diaphragmatic hernia (CDH). STUDY DESIGN: The CDH Focus Group utilized a modified Delphi method to develop these clinical consensus guidelines (CCG). Topic leaders drafted recommendations after literature review and group discussion. Each recommendation was sent to focus group members via a REDCap survey tool, and members scored on a Likert scale of 0-100. A score of > 85 with no more than 25% outliers was designated a priori as demonstrating consensus among the group. RESULTS: In the first survey 24/25 recommendations received a median score > 90 and after discussion and second round of surveys all 25 recommendations received a median score of 100. CONCLUSIONS: We present a consensus evidence-based framework for managing parenteral and enteral nutrition, somatic growth, gastroesophageal reflux disease, chylothorax, and long-term follow-up of infants with CDH.

Exploring new perspectives on congenital diaphragmatic hernia: A comprehensive review.

Congenital diaphragmatic hernia (CDH) represents a developmental anomaly that profoundly impacts the embryonic development of both the respiratory and cardiovascular systems. Understanding the influences of developmental defects, their origins, and clinical consequences is of paramount importance for further research and the advancement of therapeutic strategies for this condition. In recent years, groundbreaking studies in the fields of metabolomics and genomics have significantly expanded our knowledge regarding the pathogenic mechanisms of CDH. These investigations introduce novel diagnostic and therapeutic avenues. CDH implies a scarcity of available information within this domain. Consequently, a comprehensive literature review has been undertaken to synthesize existing data, providing invaluable insights into this rare disease. Improved comprehension of the molecular underpinnings of CDH has the potential to refine diagnostic precision and therapeutic interventions, thus potentially enhancing clinical outcomes for CDH patients. The identification of potential biomarkers assumes paramount significance for early disease detection and risk assessment in CDH, facilitating prompt recognition and the implementation of appropriate interventions. The process of translating research findings into clinical practice is significantly facilitated by an exhaustive literature review. It serves as a pivotal step, enabling the integration of novel, more effective diagnostic and therapeutic modalities into the management of CDH patients.

Mechanical ventilation in special populations.

Optimal respiratory support can only be achieved if the ventilator strategy utilized for each individual patient at any given point in the evolution of their disease process is tailored to the underlying pathophysiology. The critically ill newborn infant requires individualized patient care when it comes to mechanical ventilation. This can only occur if the clinician has a good understanding of the different pathophysiologies of a variety of conditions that can lead to respiratory failure. In this chapter we describe the key pathophysiological features of bronchopulmonary dysplasia, meconium aspiration syndrome and lung hypoplasia syndromes with emphasis on congenital diaphragmatic hernia. We review available evidence to guide management an provide specific recommendations for pathophysiologically-based mechanical ventilation support.

Pathogenesis and Physiologic Mechanisms of Neonatal Pulmonary Hypertension: Preclinical Studies.

Neonatal pulmonary hypertension (PH) is a devastating disorder of the pulmonary vasculature characterized by elevated pulmonary vascular resistance and mean pulmonary arterial pressure. Occurring predominantly because of maldevelopment or maladaptation of the pulmonary vasculature, PH in neonates is associated with suboptimal short-term and long-term outcomes because its pathobiology is unclear in most circumstances, and it responds poorly to conventional pulmonary vasodilators. Understanding the pathogenesis and pathophysiology of neonatal PH can lead to novel strategies and precise therapies. The review is designed to achieve this goal by summarizing pulmonary vascular development and the pathogenesis and pathophysiology of PH associated with maladaptation, bronchopulmonary dysplasia, and congenital diaphragmatic hernia based on evidence predominantly from preclinical studies. We also discuss the pros and cons of and provide future directions for preclinical studies in neonatal PH.

Comorbidities and Late Outcomes in Neonatal Pulmonary Hypertension.

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

Treatment Facility Case Volume and Disparities in Outcomes of Congenital Diaphragmatic Hernia Cases.

INTRODUCTION: Congenital diaphragmatic hernia (CDH) is a life-threatening, prenatally diagnosed congenital anomaly. We aim to characterize care and outcomes of infants with CDH in Texas and the impact of treating facilities volume of care. METHODS: Retrospective cohort study using a state-wide Hospital Inpatient Discharge Public Use Data File was conducted (2013-2021). Neonates and infants <1 year of age were included using CDH ICD-9/ICD-10 codes. Neonates transferred to an outside hospital were excluded to avoid double-counting. Descriptive statistics, chi-square and logistic regression analysis were performed. RESULTS: Of 1314 CDH patient encounters identified, 728 (55%) occurred at 5 higher volume centers (HVC, >75 cases), 326 (25%) at 9 mid-volume centers (MVC, 20-75 cases) and 268 (20%) at 79 low volume centers (LVC, <20 cases). HVC had lower mortality rates (18%, MVC 22% vs LVC 27%; p = 0.011) despite treating sicker patients (extreme illness severity: HVC 71%, MVC 62% vs LVC 50%; p < 0.001) with longer length-of-stay (p < 0.001). Extracorporeal membrane oxygenation was used in 136 (10%) and provided primarily at HVC. LVC treated proportionately more non-white Hispanic patients (p < 0.001) and patients from counties along the Mexican border (p < 0.001). The predicted probability of mortality in CDH patients decreases with higher treatment facility CDH case volume, with a 0.5% decrease in the odds of mortality for every additional CDH case treated (p < 0.001). CONCLUSIONS: Patients treated in HVC have significantly lower mortality despite increased severity. Our data suggest minority populations may be disproportionately treated at LVC associated with worse outcomes. TYPE OF STUDY: Retrospective Prognosis Study. LEVEL OF EVIDENCE: Level II.

Respiratory function testing for guiding ventilator mode conversion in congenital diaphragmatic hernia.

INTRODUCTION: For patients with a congenital diaphragmatic hernia, conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV) are used in initial ventilatory management. HFOV has recently been recommended as a rescue therapy; however, we use HFOV for initial ventilation management, with a preoperative challenge test for CMV conversion and respiratory function testing at the time of CMV conversion. We aimed to compare patient characteristics between CMV conversion- and HFOV-preferred treatment groups. METHODS: Ventilator settings and blood gases were retrospectively evaluated pre- and post-CMV conversion, and respiratory function tests for compliance of the respiratory system (Crs) and for resistance of the respiratory system (Rrs) were performed during the trial to CMV conversion. RESULTS: No differences were observed between the CMV conversion- and HFOV-preferred groups regarding gestational age, birth weight, and observed/expected lung area-to-head circumference ratios. The median Crs (ml/cmH2 O/kg) and Rrs (cmH2 Oï½¥kg/L/s) in the CMV conversion- and HFOV-preferred groups was 0.42 versus 0.53 (p = .44) and 467 versus 327 (p = .045), respectively. The pre and posttrial amount of change in blood gas levels and ventilator parameters in the CMV conversion- and HFOV-preferred groups were as follows: mean airway pressure, -2.0 versus 0 cmH2 O; partial pressure of carbon dioxide, 6.1 versus 2.9 Torr; alveolar-arterial oxygen difference, -39.5 versus -50 Torr; and oxygenation index, -1.0 versus -0.6; respectively. CONCLUSION: Respiratory function tests were useful in tailoring ventilator settings. Patients with high Rrs values responded better to CMV conversion.

Study protocol for a randomised cross-over trial of Neurally adjusted ventilatory Assist for Neonates with Congenital diaphragmatic hernias: the NAN-C study.

BACKGROUND: Neurally adjusted ventilatory assist (NAVA) is a mode of mechanical ventilation that delivers oxygen pressures in proportion to electrical signals of the diaphragm. The proportional assistance can be adjusted by the clinician to reduce the patient's work of breathing. Several case series of infants with congenital diaphragmatic hernias (CDH) have shown that NAVA may reduce oxygenation index and mean airway pressures. To date, no clinical trial has compared NAVA to standard methods of mechanical ventilation for babies with CDH. METHODS: The aim of this dual-centre randomised cross-over trial is to compare post-operative NAVA with assist control ventilation (ACV) for infants with CDH. If eligible, infants will be enrolled for a ventilatory support tolerance trial (VSTT) to assess their suitability for randomisation. If clinically stable during the VSTT, infants will be randomised to receive either NAVA or ACV first in a 1:1 ratio for a 4-h period. The oxygenation index, respiratory severity score and cumulative sedative medication use will be measured. DISCUSSION: Retrospective studies comparing NAVA to ACV in neonates with congenital diaphragmatic hernia have shown the ventilatory mode may improve respiratory parameters and benefit neonates. To our knowledge, this is the first prospective cross-over trial comparing NAVA to ACV. TRIAL REGISTRATION: NAN-C was prospectively registered on ClinicalTrials.gov NCT05839340  Registered on May 2023.

Congenital Diaphragmatic Hernia at a Non-ECMO Center in Jordan.

OBJECTIVES: We studied the clinical characteristics and outcomes of neonates with congenital diaphragmatic hernia (CDH) admitted to a non-extracorporeal membrane oxygenation (ECMO) center. METHODS: A retrospective chart review of neonates with CDH admitted to a University Hospital, in Amman, Jordan, between 2005 and 2019. Demographic characteristics and their management details were extracted and factors associated with survival were analyzed. RESULTS: A total of 28 neonates born with CDH were included; their survival rate was 39.3%. Onset of respiratory distress, pre-operative ventilation, and length of hospitalization were significantly associated with mortality. Survival after surgery was significantly associated with a higher gestational age and a longer hospital stay. CONCLUSION: Our study showed a high mortality rate for CDH patients. Decreasing the health inequity and improved clinical interventions could improve outcomes.

Pulmonary Artery Measurements as Postnatal Prognostic Tool in Right Congenital Diaphragmatic Hernia.

BACKGROUND: Right-sided congenital diaphragmatic hernia (RCDH) is a rare and often fatal congenital anomaly, primarily attributed to lung hypoplasia, which is associated with small branch pulmonary artery (PA). This study investigated whether postnatal PA measurements obtained through echocardiography are associated with mortality or the extracorporeal membrane oxygenation (ECMO) requirement in neonates with RCDH. METHODS: A retrospective study was conducted on neonates with RCDH born between 2008 and 2022. Echocardiography was performed on the day of birth. The diameter of the main PA (MPA) was measured at the maximal dimension, and the diameters of the left PA (LPA) and right PA (RPA) were measured at the bifurcation. The primary outcome was mortality or ECMO requirement. Parameters, including the LPA:MPA ratio, RPA:MPA ratio, Nakata index, McGoon ratio, and ejection fraction (EF), were analyzed and compared with the observed-to-expected lung-to-head ratio (o/e LHR), initial blood gas, and defect size as predictive values. RESULTS: Among 39 neonates with RCDH, 25 (64.1 %) survived without ECMO. The non-survivor or ECMO group exhibited lower o/e LHR, reduced EF, smaller LPA and RPA diameters, and larger MPA diameter than survivors. Lower LPA:MPA ratio, Nakata index, McGoon ratio, and higher initial PaCO2 were associated with adverse outcomes. Notably, the LPA:MPA ratio showed the highest predictive capability (area under the curve, 0.983; p < 0.001). CONCLUSION: The LPA:MPA ratio is a promising postnatal predictor of mortality or ECMO requirement in neonates with RCDH. Additionally, Nakata index, McGoon ratio, and initial PaCO2 are significantly correlated with outcomes. LEVEL OF EVIDENCE: This is a level III. TYPE OF STUDY: Prognostic study.

Quality of life in congenital diaphragmatic hernia survivors treated at a non-ECMO centre from 1998 to 2015: a cross-sectional study.

BACKGROUND: Survival of infants with congenital diaphragmatic hernia (CDH) has increased and more insight is warranted on the long-term issues of this condition. METHODS: We conducted a cross-sectional study on consecutively born infants with CDH treated at a non-extracorporeal membrane oxygenation centre (ECMO) from 1998 to 2015. Quality of life was evaluated using the Pediatric Quality of Life Inventory Generic Core Scale 4.0 (PedsQL(4.0)) Questionnaire and an interview was conducted to assess for CDH-related morbidity. RESULTS: 71 eligible CDH survivors were identified and 51 consented to participate: aged 5-21 years, 28 (54.9%) male, 42 (82.4%) with left-sided hernias, 10 (19.6%) needed patch repair, median length of stay in hospital was 27.96 days (IQR 18.54-61.56). Forty-nine completed the questionnaire with a median PedsQL total score for participants of 82.6 vs 83.7 of the total proxy parent score (p=0.04). Total score was significantly lower for participants aged 5-12 years compared with participants aged 13-21 years (p=0.04); however, when reported by domains, only the physical score remained significantly lower (p=0.048). Two (4.1%) participants' and 8 (16.7%) proxy parents' scores were below 70 and considered at risk of impaired quality of life. We identified the presence of CDH-related morbidity in our population, and confirmed an association between respiratory morbidity and lower PedsQL scores (p=0.04). CONCLUSION: We report an overall good quality of life in our population with CDH. However, a lower physical score was noted when compared with a national Danish cohort and individuals at risk of reduced quality of life were recognised. Structured follow-up programmes to identify and ensure early management of CDH-related issues may prevent a negative impact on quality of life.

Oxygen saturation index: an adjunct for oxygenation index in congenital diaphragmatic hernia.

OBJECTIVE: Our objective was to investigate the correlation of Oxygen Saturation Index (OSI) with Oxygenation Index (OI) and determine OSImax values that could predict need for ECMO and death in Congenital Diaphragmatic Hernia (CDH). STUDY DESIGN: This is a retrospective cohort study of infants with CDH admitted to a tertiary level VI NICU. Pearson's correlation coefficient and simple linear regression analysis were used to investigate the OSI: OI correlation, and logistic regression analysis to investigate OSImax values that predicted need for ECMO and death. RESULTS: Among the 180 infants, OSImax value of >13 at 6 h of life (HOL) best predicted need for ECMO and death. There was a strong correlation between OSI: OI paired values (r = 0.876, p < 0.001). The linear regression equation was OI = -2.4 + 2.4(OSI). CONCLUSION: OSI could be used as a valuable adjunct to OI in the clinical management of newborn infants with CDH.

Sustained inflation improves initial lung aeration in newborn rabbits with a diaphragmatic hernia.

BACKGROUND: Infants with a congenital diaphragmatic hernia (DH) have underdeveloped lungs and require mechanical ventilation after birth, but the optimal approach is unknown. We hypothesised that sustained inflation (SI) increases lung aeration in newborn kittens with a DH. METHODS: In pregnant New Zealand white rabbits, a left-sided DH was induced in two fetal kittens per doe at 24-days gestation (term = 32 days); litter mates acted as controls. DH and control kittens were delivered by caesarean section at 30 days, intubated and mechanically ventilated (7-10 min) with either an SI followed by intermittent positive pressure ventilation (IPPV) or IPPV throughout. The rate and uniformity of lung aeration was measured using phase-contrast X-ray imaging. RESULTS: Lung weights in DH kittens were ~57% of controls. An SI increased the rate and uniformity of lung aeration in DH kittens, compared to IPPV, and increased dynamic lung compliance in both control and DH kittens. However, this effect of the SI was lost when ventilation changed to IPPV. CONCLUSION: While an SI improved the rate and uniformity of lung aeration in both DH and control kittens, greater consideration of the post-SI ventilation strategy is required to sustain this benefit. IMPACT: Compared to intermittent positive pressure ventilation (IPPV), an initial sustained inflation (SI) increased the rate and uniformity of lung aeration after birth. However, this initial benefit is rapidly lost following the switch to IPPV. The optimal approach for ventilating CDH infants at birth is unknown. While an SI improves lung aeration in immature lungs, its effect on the hypoplastic lung is unknown. This study has shown that an SI greatly improves lung aeration in the hypoplastic lung. This study will guide future studies examining whether an SI can improve lung aeration in infants with a CDH.

The impact of a care bundle with an emphasis on hemodynamic assessment on the short-term outcomes in neonates with congenital diaphragmatic hernia.

OBJECTIVE: To evaluate the short-term outcomes of implementing a care bundle emphasizing frequent hemodynamic assessments by echocardiography in neonates with congenital diaphragmatic hernia (CDH). STUDY DESIGN: This was a retrospective cohort study of infants with CDH admitted to a quaternary perinatal unit from January 2013 to March 2021. The primary composite outcome was defined as mortality or use of extracorporeal membrane oxygenation or need for respiratory support at discharge. RESULTS: We identified 37 and 20 CDH infants in Epoch I and II, respectively. More patch repairs (50% vs. 21.9%, p = 0.035) and echocardiograms (6[4-8] vs. 1[0-5], p = 0.003) were performed in Epoch II. While there were no differences in the primary outcome, there was a reduction in mortality in Epoch II (0% vs. 27%, p = 0.01). CONCLUSION: With the implementation of a CDH care bundle with an emphasis on hemodynamic assessment, we demonstrated a significant reduction in mortality.

Early Ventilator Management for Infants With Congenital Diaphragmatic Hernia: Impact of a Standardized Clinical Practice Guideline.

BACKGROUND: Infants with congenital diaphragmatic hernia (CDH) experience high morbidity and mortality due to pulmonary arterial hypertension and hypoplasia. Mechanical ventilation is a central component of CDH management. Our objective was to evaluate the impact of a standardized clinical practice guideline (implemented in January 2012) on ventilator management for infants with CDH, and associate management changes with short-term outcomes, specifically extracorporeal membrane oxygenation (ECMO) utilization and survival to discharge. METHODS: We conducted a retrospective pre-post study of 103 CDH infants admitted from January 2007-July 2021, divided pre- (n = 40) and post-guideline (n = 63). Clinical outcomes, ventilator settings, and blood gas values in the first 7 days of mechanical ventilation were compared between the pre- and post-guideline cohorts. RESULTS: Post-guideline, ECMO utilization decreased (11% vs 38%, p = 0.001) and survival to discharge improved (92% vs 68%, p = 0.001). More post-guideline patients remained on conventional mechanical ventilation without need for escalation to high-frequency ventilation or ECMO, and had higher pressures and PaCO2 with lower FiO2 and PaO2 (p < 0.05). CONCLUSIONS: Standardized ventilator management optimizing pressures for adequate lung expansion and minimizing oxygen toxicity improves outcomes for infants with CDH. LEVEL OF EVIDENCE: III.