Permissive hypercapnia in the management of congenital diaphragmatic hernia: our institutional experience

Implementation of the Oxygen Saturation Index as a Predictor of Outcome in Prenatally Diagnosed CDH Neonates in the First 24 Hours of Life

AIMS

This study aimed to evaluate the Oxygen Saturation Index (OSI) as a noninvasive measure for early postnatal management and outcome prediction in neonates with congenital diaphragmatic hernia (CDH). Additionally, the study analyzed the correlation and predictive ability of OSI, Oxygenation Index (OI), Horovitz Index (HI), and partial pressure of arterial oxygen (PaO2) regarding mortality and the need for extracorporeal membrane oxygenation (ECMO).

METHODS

A retrospective, single-center study using data from 2013 to 2020. Parameters for calculating indices were extracted from patient charts every hour during the first 24 h of life. Statistical analyses included ROC analysis for predictive cut-off values and Spearman's rank for correlation assessments.

RESULTS

The study included 138 neonates. Postductal OSI demonstrated high sensitivity (80%-85%) and negative predictive value (NPV) for predicting mortality and ECMO need, with cut-off values between 11.5 and 13. Optimal cut-off values for predicting ECMO need were 10 at 12 and 24 h (sensitivity 96.7%). OSI, OI, HI, and PaO2 showed comparable predictive capabilities with strong correlations. The lowest OI of 18 predicted mortality with a sensitivity of 75% and specificity of 90.9%. Strong correlations were found between the lowest PaO2 and lowest HI (0.963-0.974), and between highest OI and lowest PaO2 (-0.922 to -0.945).

CONCLUSION

OSI is a promising index for predicting outcomes in CDH neonates, showing strong correlation with indices like OI and HI. Despite limitations, OSI provides continuous, bedside monitoring without invasive blood sampling. Further prospective studies are needed to validate these findings and establish new cut-off values.

Ventilator strategies in congenital diaphragmatic hernia

This review focuses on contemporary mechanical ventilator practices used in the initial management of neonates born with congenital diaphragmatic hernia (CDH). Both conventional and non-conventional ventilation modes in CDH are reviewed. Special emphasis is placed on the rationale for gentle ventilation and the current evidence-based clinical practice guidelines that are recommended for supporting these fragile infants. The interplay between CDH lung hypoplasia and other key cardiopulmonary elements of the disease, namely a reduced pulmonary vascular bed, abnormal pulmonary vascular remodeling, and left ventricular hypoplasia, are discussed. Finally, we provide insights into future avenues for mechanical ventilator research in CDH.

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.

Transpyloric Tube Placement Shortens Time to Full Feeding in Left Congenital Diaphragmatic Hernia

BACKGROUND

Nutritional complications have an impact in both short- and long-term morbidity of patients with congenital diaphragmatic hernia (CDH). We aimed to compare time to full enteral tube feeding depending on route -gastric (GT) or transpyloric (TPT)- in newborns with left CDH (L-CDH).

METHODS

Retrospective cohort study of L-CDH patients admitted to a referral tertiary care NICU between January 2007 and December 2014. Lethal chromosomal abnormalities and death before initiation of enteral nutrition were exclusion criteria.

RESULTS

37 patients were fed through GT, 46 by TPT. TPT children took 11.0 (6.8) days to reach full enteral tube feeding and spent 16.6 (8.1) days on parenteral nutrition vs 16.8 (14.7) days (p = 0.041) and 22.7 (13.5) days (p = 0.020) of GT patients. TPT children had 3.9 (2.4) days of fasting due to GI issues and 20% had episodes of decreased rates of enteral nutrition for extra-GI complications vs 11.4 (11.1) days (p = 0.028) and 49% (p = 0.006). According to the best fitting model (R2 0.383, p < 0.001), the TPT-group achieved full enteral feeding 8.4 days earlier than the GT-group (95% CI -14.76 to - 2.02 days), after adjustment by severity of illness during the first days, o/e LHR_liver and class of diaphragmatic defect. There were no differences in growth outcomes and length of stay between survivors of GT and TPT groups.

CONCLUSION

TPT shortens time to full enteral nutrition, especially in the most severe L-CDH patients. We propose that placement of a TPT at the end of the surgical repair procedure should be considered, especially in higher-risk patients.

LEVEL OF EVIDENCE

Treatment study, Level III. Retrospective comparative, case-control study.

Congenital diaphragmatic hernia: a narrative review of controversies in neonatal management

The consequences of most hernias can be immediately corrected by surgical repair. However, this isn't always the case for children born with a congenital diaphragmatic hernia. The derangements in physiology encountered immediately after birth result from pulmonary hypoplasia and hypertension caused by herniation of abdominal contents into the chest early in lung development. This degree of physiologic compromise can vary from mild to severe. Postnatal management of these children remains controversial. Although heavily studied, multi-institutional randomized controlled trials are lacking to help determine what constitutes best practice. Additionally, the results of the many studies currently within the literature that have investigated differing aspect of care (i.e., inhaled nitric oxide, ventilator type, timing of repair, role of extracorporeal membrane oxygenation, etc.) are difficult to interpret due to the small numbers investigated, the varying degree of physiologic compromise, and the contrasting care that exists between institutions. The aim of this paper is to review areas of controversy in the care of these complex kids, mainly: the use of fraction of inspired oxygen, surfactant therapy, gentle ventilation, mode of ventilation, medical management of pulmonary hypertension (inhaled nitric oxide, sildenafil, milrinone, bosentan, prostaglandins), the utilization of extracorporeal membrane oxygenation, and the timing of surgical repair.

Respiratory Support of Infants With Congenital Diaphragmatic Hernia

Optimisation of respiratory support of infants with congenital diaphragmatic hernia (CDH) is critical. Infants with CDH often have severe lung hypoplasia and abnormal development of their pulmonary vasculature, leading to ventilation perfusion mismatch. It is vital that lung protective ventilation strategies are employed during both initial stabilisation and post-surgical repair to avoid ventilator induced lung damage and oxygen toxicity to prevent further impairment to an already diminished gas-exchanging environment. There is a lack of robust evidence for the routine use of surfactant therapy during initial resuscitation of infants with CDH and thus administration cannot be recommended outside clinical trials. Additionally, inhaled nitric oxide has been shown to have no benefit in reducing the mortality rates of infants with CDH. Other therapeutic agents which beneficially act on pulmonary hypertension are currently being assessed in infants with CDH in randomised multicentre trials. The role of novel ventilatory modalities such as closed loop automated oxygen control, liquid ventilation and heliox therapy may offer promise for infants with CDH, but the benefits need to be determined in appropriately designed clinical trials.

Predicting lethal pulmonary hypoplasia in congenital diaphragmatic hernia (CDH): Institutional experience combined with CDH registry outcomes

BACKGROUND

The Severe Pulmonary Hypoplasia and Evaluation for Resuscitative Efforts (SPHERE) protocol was developed to attempt to identify CDH patients with likely lethal pulmonary hypoplasia. We present our experience with this protocol and utilize the CDH Registry to critically assess the protocol.

METHODS

SPHERE patients identified based on prenatal imaging (10/2009-1/2018) were offered ECMO if meeting postnatal physiologic criteria, while others received comfort measures. Within the CDH Registry, patients with suspected severe CDH were identified and separated into "passed" (lowest pCO2 ≤100) versus "failed" (lowest pCO2 >100) groups.

RESULTS

Of 23 SPHERE patients, 57% (13/23) passed criteria for ECMO and survival was 46% (6/13) in that cohort. Of 4912 patients in the CDH Registry, 265 met criteria. There was no difference in survival rates between those that "passed" (122/227; 54%) versus "failed" (18/38; 47%). However, the latter had longer ECMO runs and more required ventilator/ECMO support at 30 days. Amongst survivors, the "failed" group had longer hospital stays and more frequently required tube feeds at discharge.

CONCLUSIONS

The SPHERE protocol did not predict mortality in the CDH Registry. However, our data suggest resource utilization is significant when unable to reach pCO2 ≤100 despite resuscitation. Morbidity remains high in this group.

LEVEL OF EVIDENCE

Level III ANNOTATION OF CHANGES: Institutional Review Board Approval at University of Michigan (HUM00031524 and HUM00044010) TYPE OF STUDY: Retrospective Review.

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.

Is Anesthesia Bad for the Brain? Current Knowledge on the Impact of Anesthetics on the Developing Brain

There are compelling preclinical data that common general anesthetics cause increased neuroapoptosis in juvenile animals. Retrospective studies demonstrate that young children exposed to anesthesia have school difficulties, which could be caused by anesthetic neurotoxicity, perioperative hemodynamic and homeostatic instability, underlying morbidity, or the neuroinflammatory effects of surgical trauma. Unnecessary procedures should be avoided. Baseline measures of blood pressure are important in determining perioperative blood pressure goals. Inadvertent hypocapnia or moderate hypercapnia and hyperoxia or hypoxia should be avoided. Pediatric patients should be maintained in a normothermic, euglycemic state with neutral positioning. Improving outcomes of infants and children requires the collaboration of anesthesiologists, surgeons, pediatricians and neonatologists.

Beyond Anesthesia Toxicity: Anesthetic Considerations to Lessen the Risk of Neonatal Neurological Injury

Infants who undergo surgical procedures in the first few months of life are at a higher risk of death or subsequent neurodevelopmental abnormalities. Although the pathogenesis of these outcomes is multifactorial, an understanding of the nature and pathogenesis of brain injury in these infants may assist the anesthesiologist in consideration of their day-to-day practice to minimize such risks. This review will summarize the main types of brain injury in preterm and term infants and their key pathways. In addition, the review will address key potential pathogenic pathways that may be modifiable including intraoperative hypotension, hypocapnia, hyperoxia or hypoxia, hypoglycemia, and hyperthermia. Each of these conditions may increase the risk of perioperative neurological injury, but their long-term ramifications are unclear.

Congenital diaphragmatic hernia: current management strategies from antenatal diagnosis to long-term follow-up

Congenital diaphragmatic hernia (CDH) is a developmental birth defect consisting of a diaphragmatic defect and abnormal lung development. CDH complicates 2.3-2.8 per 10,000 live births. Despite efforts to standardize clinical practice, management of CDH remains challenging. Frequent re-evaluation of clinical practices in CDH reveals that management of CDH is evolving from one of postnatal stabilization to prenatal optimization. Translational research reveals promising avenues for in utero therapeutic intervention, including fetoscopic endoluminal tracheal occlusion. These remain highly experimental and demand improved antenatal diagnostics. Timely diagnosis of CDH and identification of severely affected fetuses allow time for delivery planning or in utero therapeutics. Optimal perinatal care and surgical treatment strategies are highly debated. Improved CDH mortality rates have placed increased emphasis on identifying and monitoring the long-term sequelae of disease throughout childhood and into adulthood. We review the current management strategies for CDH, highlighting where progress has been made, and where future developments have the potential to revolutionize care in this vulnerable patient population.

The role of ECMO in the management of congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is the most common indication for extra-corporeal membrane oxygenation (ECMO) for neonatal respiratory failure. CDH management is evolving with advanced prenatal diagnostic imaging modalities. The risk profiles of infants receiving ECMO for CDH are shifting towards higher risk. Many clinicians are developing and following clinical practice guidelines to standardize and optimize the care of CDH neonates. Despite these efforts, there are significant differences in the practice patterns among ECMO centers as to how and when they choose to initiate ECMO for CDH, when they believe repair is safe, as well as many other nuances that are based on center experience or style. The purpose of this report is to summarize our current understanding of the new and recent developments regarding management of infants with CDH managed with ECMO.

How to ventilate preterm infants with lung compliance close to circuit compliance: real-time simulations on an infant hybrid respiratory simulator

Circuit compliance close to lung compliance can create serious problems in effective and safe mechanical ventilation of preterm infants. We considered what ventilation technique is the most beneficial in this case. A hybrid (numerical-physical) simulator of infant respiratory system mechanics, the Bennett Ventilator and NICO apparatus were used to simulate pressure-controlled ventilation (PC) and volume-controlled ventilation with constant flow (VCV_CF) and descending flow (VCV_DF), under permissive hypercapnia (PHC) (6 ml kg^-1) and normocapnia (SV) (8 ml kg^-1) conditions. Respiratory rate (RR) was 36 or 48 min^-1 and PEEP was 0.3 or 0.6 kPa. Peak inspiratory pressure (PIP), mean airway pressure (MAP), and work of breathing by the ventilator (WOB) were lower (P < 0.01, 1 - β = 0.9) using the PHC strategy compared to the SV strategy. The WOB increased (P < 0.01; 1 - β = 0.9) when the RR increased. The PC, VCV_CF, and VCV_DF modes did not differ in minute ventilation produced by the ventilator (MV_V), but the PC mode delivered the highest minute ventilation to the patient (MV_T) (P < 0.01; 1 - β = 0.9) at the same PIP, MAP, and WOB. The most beneficial ventilation technique appeared to be PC ventilation with the PHC strategy, with lower RR (36 min^-1). Graphical abstract The effectiveness of an infant ventilation depending on circuit compliance to lung compliance ratio (C_v C_L ^-1) and inspiration time (T_i). V_V, V_T, tidal volume set on the ventilator and delivered to patient, respectively.

Congenital diaphragmatic hernia: Impact of contemporary management strategies on perinatal outcomes

OBJECTIVE

This study aims to review temporal changes in perinatal management and 1-year survival outcomes of cases of congenital diaphragmatic hernia (CDH) from 1996 to 2015 in Western Australia (WA).

METHOD

This research is a retrospective study of all cases of CDH in WA from 1996 to 2015 identified from five independent databases within the WA health network. Detailed information pertaining to pregnancy and survival outcomes were obtained from review of maternal and infant medical records.

RESULTS

There were 215 cases of CDH with 164 diagnosed prenatally. Between 1996 and 2010, a decline in live birth rates for CDH-affected pregnancies was observed, reaching a nadir of 5.3 per 10 000 births before increasing to a peak of 9.73 per 10 000 births in 2011-2015. A corresponding decline was seen in the number of pregnancies terminated in the same period from 8.3 to 4.6 per 10 000 births (P = 0.14) and an increase in survival of live births from 38.9% to 81.3% (P = 0.01).

CONCLUSION

The improved overall survival rate in infants with CDH over the last 20 years may have resulted in an increased tendency for women to continue their pregnancy with a concomitant decline in termination rates. Information from this study will help in the counselling of women following prenatal detection of CDH.

Improving outcome in congenital diaphragmatic hernia - experience of a tertiary center without ECMO

BACKGROUND

Congenital diaphragmatic hernia (CDH) has a high mortality rate, representing a therapeutic challenge. Prenatal diagnosis (PND) is essential in defining optimal perinatal strategy, particularly delivery planning. Hospital Pediátrico de Coimbra is the referral centre for all neonatal surgery, particularly CDH, for the central region of Portugal. The aim was to evaluate clinical management and outcome of newborns with CDH.

METHODS

An exploratory retrospective study made up of newborns admitted to PICU with CDH was undertaken between January 1995 and December 2014. Two groups were formed based on their year of admission: group A (1995- 2004) and group B (2005- 2014) and were compared.

RESULTS

The mean birth weight of the 69 newborns admitted was 2.762 ± 696 g; the median of the gestational age was 38 weeks. Associated malformations were observed in 28 (40.5%) and 15 (21.7%) had a right-sided diaphragm defect. The global mortality was 13.0%; in group A was significantly higher than in group B (22.2 vs 3.0%; p = 0.029). A reduction in mortality throughout the years was confirmed after adjusting for POS score (OR = 0.77; 95% CI: 0.62- 0.96, p = 0.021). PND was made in 30.6% of cases in the group A and 66.7% in the group B (p = 0.03). Tertiary perinatal hospital birth was achieved in 60% of newborns in the group A versus 84.8% in group B (p = 0.022). Maximum fraction of inspired oxygen showed a statistically significant difference between the two study groups (60% vs 40%; p = 0.009).

CONCLUSIONS

A significant decrease in mortality was observed throughout the study. The authors highlight the increase in prenatal diagnosis and an improvement in perinatal care with planning delivery as important contributors to these results.

Ventilation modalities in infants with congenital diaphragmatic hernia

Neonates with congenital diaphragmatic hernia are among the more complex patients to support with mechanical ventilation. They have particular features that add to the difficulties already present in the neonatal patient. A ventilation strategy tailored to the patient's underlying physiology rather than mode of ventilation is a crucial issue for clinicians treating these delicate patients.

ECMO in CDH: Is there a role?

Despite wide use and decades of experience, survival of congenital diaphragmatic hernia (CDH) patients treated with extra-corporeal membrane oxygenation (ECMO), as reported by the extra-corporeal life support organization (ELSO), remains unchanged at 50%. High-survival rates both with and without utilizing ECMO have been reported, fueling questions about the utility of ECMO support in this difficult population. This review looks at data from the Congenital Diaphragmatic Hernia Study Group and individual center reports, to evaluate the role of ECMO in CDH, focusing on defining the patients most likely to benefit, and discussing how those benefits can best be achieved. These data show that ECMO improves survival in those CDH patients who are most severely affected, but potential complications of ECMO delivery outweigh benefit in patients with less severely affected. Improved results can be expected by minimizing ECMO complications, and by improving rates of CDH repair in patients that require ECMO.

Risk factors for postoperative mortality in congenital diaphragmatic hernia: a single-centre observational study

BACKGROUND

The management of congenital diaphragmatic hernia (CDH) is a major challenge. The mortality is dependent on associated malformations, the severity of pulmonary hypoplasia, pulmonary hypertension and iatrogenic lung injury associated with aggressive mechanical ventilation. The aims of the study were to investigate the mortality over time in a single paediatric surgical centre, to compare the results with recent reports and to define the risk factors for mortality.

METHODS

The medical records of infants with CDH from two time periods: 1995-2005 and 2006-2016 were reviewed. Cox regression was used for statistical analysis.

RESULTS

The study included 113 infants. The mortality rate was significantly decreased in the later time period, compared to the earlier, 4.4 and 17.9%, respectively. At the early time period five patients (7.5%) were treated with ECMO and in the later time period ECMO was used in three patients (6.5%). The mortality in ECMO-treated patients was 50% in both time periods. Prenatal diagnosis, intrathoracic liver, low Apgar score and low birth weight were defined as independent risk factors for mortality.

CONCLUSION

Despite no significant differences in the incidence of independent risk factors and the use of ECMO between the two time periods, mortality decreased over time. The mortality was lower than previously reported. The results indicate that there are many important factors involved in a successful outcome after CDH repair. Large multicentre studies are necessary to define those critical factors and to determine optimal treatment strategies.

Repair of congenital diaphragmatic hernia during extracorporeal life support: experience with six neonates

BACKGROUND

The management of congenital diaphragmatic hernia (CDH) in neonates has evolved considerably over the last three decades. Initial stabilization followed by surgical repair is the current standard of care. A subset fails to achieve adequate oxygenation with medical management, including the use of high frequency oscillation and inhaled nitric oxide. The mortality in this group exceeds 80% without additional management strategies. Extracorporeal life support (ECLS) is a well-established modality for managing these neonates with CDH and has been shown to improve early survival in selected cases.

METHODS

This is a retrospective analysis of six neonates with CDH who underwent repair during ECLS between September 2011 and November 2014.

RESULTS

Of 24 admissions with CDH, there were six neonates (25%) who required ECLS. All the six had CDH repair during ECLS. There were no intra-operative bleeding complications. There were no clotting complications related to stopping heparin during CDH repair. There was one hospital death. Five neonates were weaned from ECLS and discharged home.

CONCLUSIONS

Data from our small cohort of patients illustrate that early survival is possible in extremely compromised neonates who otherwise would have died without ECLS. Our experience demonstrates that CDH repair can safely be performed during ECLS. Use of ECLS, early repair during ECLS, lung protective ventilation strategies and aggressive management of pulmonary hypertension were associated with good early survival. ECLS should be considered as an integral part of therapeutic armamentarium for CDH in neonates.

Standardized Postnatal Management of Infants with Congenital Diaphragmatic Hernia in Europe: The CDH EURO Consortium Consensus - 2015 Update

In 2010, the congenital diaphragmatic hernia (CDH) EURO Consortium published a standardized neonatal treatment protocol. Five years later, the number of participating centers has been raised from 13 to 22. In this article the relevant literature is updated, and consensus has been reached between the members of the CDH EURO Consortium. Key updated recommendations are: (1) planned delivery after a gestational age of 39 weeks in a high-volume tertiary center; (2) neuromuscular blocking agents to be avoided during initial treatment in the delivery room; (3) adapt treatment to reach a preductal saturation of between 80 and 95% and postductal saturation >70%; (4) target PaCO2 to be between 50 and 70 mm Hg; (5) conventional mechanical ventilation to be the optimal initial ventilation strategy, and (6) intravenous sildenafil to be considered in CDH patients with severe pulmonary hypertension. This article represents the current opinion of all consortium members in Europe for the optimal neonatal treatment of CDH.

Pediatric Pulmonary Hypertension: Guidelines From the American Heart Association and American Thoracic Society

Pulmonary hypertension is associated with diverse cardiac, pulmonary, and systemic diseases in neonates, infants, and older children and contributes to significant morbidity and mortality. However, current approaches to caring for pediatric patients with pulmonary hypertension have been limited by the lack of consensus guidelines from experts in the field. In a joint effort from the American Heart Association and American Thoracic Society, a panel of experienced clinicians and clinician-scientists was assembled to review the current literature and to make recommendations on the diagnosis, evaluation, and treatment of pediatric pulmonary hypertension. This publication presents the results of extensive literature reviews, discussions, and formal scoring of recommendations for the care of children with pulmonary hypertension.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Outcomes in the physiologically most severe congenital diaphragmatic hernia (CDH) patients: Whom should we treat?

PURPOSE

Centers that care for newborns with congenital diaphragmatic hernia (CDH) may impose selection criteria for offering or limiting aggressive support in those patients most severely affected. The purpose of this study was to analyze outcomes in newborns with highly severe CDH uniformly treated for survival.

METHODS

We reviewed 172 consecutive inborn patients without associated lethal anomalies treated at a single institution with a dedicated CDH program. Survival, respiratory outcome, and time to discharge in the most severe 10% (or fewer) of patients based on the physiologic measures of 5-minute Apgar, CDH Study Group (CDHSG) predicted survival, need for ECMO in the first 6 hours, and need for ECMO in the first 3 hours of life were studied. We also identified patients with best PaCO2 greater than 100 and best pH less than 7.0. A multivariate model (AUC-0.92) predicting mortality was also used to define the most severe 10%.

RESULTS

Of 172 consecutive inborn patients, 18 had a 5-minute Apgar of 3 or less, and 11 survived (61%), 10 had a 5-minute Apgar of 2 or less, and 6 survived (60%), and 6 had a 5-minute Apgar of 1 or less, and 4 survived (67%). Seventeen had a CDHSG predicted survival less than 25%, and 9 survived (53%). Thirteen of 172 required ECMO for rescue in the first 6 hours of life, and 9 survived (69%), including 7 in the first 3 hours, and 5 survived (71%). Despite focused resuscitation in the delivery room and high levels of ventilatory support, 22 patients had a best PCO2 greater than 100 and best pH less than 7.0 for 1 hour or longer. Twelve of these 22 survived to discharge (55%). Of 17 defined by multivariate predictive modeling as the most severe, 8 survived (47%) with zero of the 3 ECMO ineligible prematures surviving. Of the 16 (10%) most severe ECMO-eligible patients, 10 of 16 survived (63%). All survivors were discharged home on no ventilatory support greater than nasal cannula oxygen.

CONCLUSION

In newborn CDH patients without lethal associated anomalies, accepted measures of physiologic severity failed to predict mortality. Survival met or exceeded 50% even in the most severe 10% as defined by these measures. These data support the practice of treating each patient for survival regardless of the physiologic severity in the first hours of life, and selection criteria for not offering ECMO should be reevaluated where practiced.

Optimal timing of congenital diaphragmatic hernia repair in infants on extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is a vital pre-operative adjunct for the stabilization of patients with severe congenital diaphragmatic hernia (CDH) that develop cardiorespiratory failure. The optimal timing of diaphragmatic repair in patients with CDH that require ECMO remains controversial. This article offers a review of the data available addressing the risks and outcomes of patients who require ECMO support with regard to timing of repair.

Understanding and treating pulmonary hypertension in congenital diaphragmatic hernia

Lung hypoplasia and pulmonary hypertension are classical features of congenital diaphragmatic hernia (CDH) and represent the main determinants of survival. The mechanisms leading to pulmonary hypertension in this malformation are still poorly understood, but may combine altered vasoreactivity, pulmonary artery remodeling, and a hypoplastic pulmonary vascular bed. Efforts have been directed at correcting the "reversible" component of pulmonary hypertension of CDH. However, pulmonary hypertension in CDH is often refractory to pulmonary vasodilators. A new emerging pattern of late (months after birth) and chronic (months to years after birth) pulmonary hypertension are described in CDH survivors. The true incidence and implications for outcome and management need to be confirmed by follow-up studies from referral centers with high patient output. In order to develop more efficient strategies to treat pulmonary hypertension and improve survival in most severe cases, the ultimate therapeutic goal would be to promote lung and vascular growth.

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

OBJECTIVES

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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