Extracorporeal Membrane Oxygenation For Congenital Diaphragmatic Hernia Research Articles

Outcomes after Extracorporeal Membrane Oxygenation in Neonates with Congenital Diaphragmatic Hernia: A Single-Center Experience.

BackgroundCongenital diaphragmatic hernia (CDH) is a rare disease often requiring mechanical ventilation after birth. In severe cases, extracorporeal membrane oxygenation (ECMO) may be needed. This study analyzed the outcomes of patients with CDH treated with ECMO and investigated factors related to in-hospital mortality.MethodsAmong 254 newborns diagnosed with CDH between 2008 and 2020, 51 patients needed ECMO support. At Asan Medical Center, a multidisciplinary team approach has been applied for managing newborns with CDH since 2018. Outcomes were compared between hospital survivors and nonsurvivors.ResultsECMO was established at a median of 17 hours after birth. The mean birth weight was 3.1±0.5 kg. Twenty-three patients (23/51, 45.1%) were weaned from ECMO, and 16 patients (16/51, 31.4%) survived to discharge. The ECMO mode was veno-venous in 24 patients (47.1%) and veno-arterial in 27 patients (52.9%). Most cannulations (50/51, 98%) were accomplished through a transverse cervical incision. No significant between-group differences in baseline characteristics and prenatal indices were observed. The oxygenation index (1 hour before 90.0 vs. 51.0, p=0.005) and blood lactate level (peak 7.9 vs. 5.2 mmol/L, p=0.023) before ECMO were higher in nonsurvivors. Major bleeding during ECMO more frequently occurred in nonsurvivors (57.1% vs. 12.5%, p=0.007). In the multivariate analysis, the oxygenation index measured at 1 hour before ECMO initiation was identified as a significant risk factor for in-hospital mortality (odds ratio, 1.02; 95% confidence interval, 1.01–1.04; p=0.05).ConclusionThe survival of neonates after ECMO for CDH is suboptimal. Timely application of ECMO is crucial for better survival outcomes.

Extracorporeal Membrane Oxygenation in Congenital Diaphragmatic Hernia.

Congenital diaphragmatic hernia (CDH) is characterized by failure of diaphragmatic development with lung hypoplasia and persistent pulmonary hypertension of the newborn (PPHN). If conventional treatment with gentle ventilation and optimized vasoactive medication fails, extracorporeal membrane oxygenation (ECMO) may be considered. The benefits of ECMO in CDH are still controversial, since there are only few randomized trials demonstrating the advantages of this therapeutic option. At present, there is no precise prenatal and/or early postnatal prognostication parameter to predict reversibility of PPHN in CDH patients. Indications for initiating ECMO include either respiratory or circulatory parameters, which are also undergoing continuous refinement. Centers with higher case numbers and the availability of ECMO published promising survival rates, but data on long-term results, including morbidity and quality of life, are rare. Survival might be influenced by the timing of ECMO initiation and the timing of surgical repair. In this regard a trend toward early initiation of ECMO and early surgery on ECMO exists. The results concerning the cannulation modes are similar and a consensus on time limit for ECMO runs does not exist. The use of ECMO in CDH will continue to be evaluated, and prospective randomized trials and registry network are necessary to help answering the addressed questions of patient selection and management.

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.

Combined treatments and outcomes with ECMO

In this issue of The Journal two articles explore the use of extracorporeal membrane oxygenation (ECMO) in combination with hypothermia or with steroids, and a third article reports outcomes of ECMO for congenital diaphragmatic hernia. First the outcomes. Davis et al report the experience in the United Kingdom for using ECMO to try to save infants with congenital diaphragmatic hernia (CDH). Of the 73 infants offered ECMO in the United Kingdom from 1991 to 2000, 63% came off ECMO, 58% survived to discharge, but only 37% survived to 1 year. Only 7 of the original 73 patients were free of neurodevelopmental deficits or medical problems. This dismal clinical experience documents a true risk of adverse outcomes of about 90%. Many of these infants were not managed by the more conservative ventilation and oxygenation goals that are now being evaluated. Those newer management approaches also will need to be evaluated for their effects on long-term outcome, which hopefully will be better than this dismal experience. One option is to combine ECMO with hypothermia. Hypothermia is being intensively investigated as a method to decrease brain injury after birth asphyxia. As reported above, poor neurodevelopmental outcomes are common after ECMO and no doubt are multifactorial in origin. Probable causes include the cardiorespiratory failure before ECMO and events surrounding the initiation of and maintenance of ECMO. Many infants may have the equivalent of an asphyxial event, and hypothermia might improve outcomes for ECMO patients. Several large trials of hypothermia for birth asphyxia will soon be available to answer the question of the efficacy of hypothermia. Horan et al report that infants on ECMO can be managed with hypothermia with no apparent adverse outcomes. This pilot study evaluated 5 groups of 5 patients each who were sequentially targeted to a lower temperature or a longer duration of hypothermia. The study is a nice demonstration of a staged evaluation of a high-risk therapy within the context of another high-risk therapy. If hypothermia is beneficial for birth asphyxia, the study of Horan et al will be the basis for a randomized trial of hypothermia during ECMO. The third report tests the hypothesis that the old stand-by therapy of high-dose corticosteroid would benefit infants on ECMO. Corticosteroids are often used because of the pulmonary inflammation associated with the original cause of the respiratory failure (meconium, sepsis, pneumonia) or the therapy before ECMO (oxygen, mechanical ventilation). Griffin et al found that although dexamethasone improved the radiographic lung injury score, there was no benefit for decreasing the duration of ECMO or for survival. As in other clinical settings, short-term benefits of corticosteroids do not necessarily improve outcomes. ECMO is a complex and expensive therapy that is offered to a diverse population of critically ill patients who are simultaneously receiving multiple other treatments. Caution is in order to try to avoid complications of treatments that are either not helpful or harmful. Page 296 (Griffin) Page 301 (Horan) Page 309 (Davis)

The Role of ECMO in Neonates with CDH

Source: The Congenital Diaphragmatic Hernia Study Group. Does extracorporeal membrane oxygenation improve survival in neonates with congenital diaphragmatic hernia? J Ped Surg. 1999;34(5):720–724; discussion 724–725.While the benefit from extracorporeal membrane oxygenation (ECMO) in improving survival of neonates with congenital diaphragmatic hernia (CDH) has never been clearly demonstrated with a randomized controlled trial, the lack of alternative therapy and the high mortality rate (approximately one-third) has led to widespread use of this aggressive and costly therapy. This study analyzes data from a CDH registry involving 65 centers with and without ECMO capability to determine if ECMO improved survival after adjusting for overall risk of mortality. Data were available for 632 neonates with birth weight (BW) >2kg, of whom 289 received ECMO. Patients were divided into quintiles based on their predicted risk of death (using BW and 5 minute Apgar). After adjusting for risk of death, ECMO was associated with significantly higher mortality in the 2 quintiles with the lowest risk of death, and lower mortality in the quintile with the highest risk of death, ≥80%. The first 2 groups accounted for 68% of the patients while the latter group for 5%. There was no significant association between ECMO and mortality in the middle 2 quintiles. The authors conclude that ECMO makes a difference in survival for infants at high risk of death. The apparent association of ECMO with lower survival in infants in the 2 lowest quintiles is unexplained, but may be due to a failure of the predictive model to adequately adjust for differences between infants receiving and not receiving ECMO in these groups.This article by the Congenital Diaphragmatic Hernia Group is important because it is one of the first publications from this large, voluntary collaboration of physicians who follow children with diaphragmatic hernia. The important message in this study was that ECMO has value in improving survival for infants with high-risk diaphragmatic hernia. With that in mind, some consideration should probably be given to delivery of infants with congenital diaphragmatic hernia close to an ECMO center.The ability to tell the effect of ECMO on improved survival rests on whether or not the infants with CDH who received ECMO and those who did not were comparable. The authors attempt to do so by stratifying on predicted risk of death (based on birth weight and Apgar), and then comparing survival within those strata. The authors and the commentator point out that ECMO appears to be associated with better survival in the highest risk group. However, survival in the two lowest risk groups was actually poorer in those infants receiving ECMO. The problems in sorting out the effect of ECMO are precisely those seen in studies which are not prospective, controlled clinical trials. In all likelihood, there are underlying differences (eg, degree of congenital lung dysplasia) between the two groups which were not adequately adjusted for in the model. Furthermore, even if the results in the highest risk group were real, and those in the lowest risk groups were not, the overall survival would only increase by 1.4% since the high risk group only accounts for 5% of CDH patients. The optimal use of ECMO in CDH is not yet apparent and almost certainly can only be ascertained by further detailed, analytic reports from this multi-center collaborative study group.

Nitric oxide avoids the need for a second course of ECMO in congenital diaphragmatic hernia

Inhaled nitric oxide was effectively used to avoid the need for a second course of extracorporeal membrane oxygenation (ECMO) in a neonate with a congenital diaphragmatic hernia and recurrent pulmonary hypertension following ECMO.

Do we use the right entry criteria for extracorporeal membrane oxygenation in congenital diaphragmatic hernia?

In a retrospective review we analysed alveolar-arterial oxygen difference (AaDO 2) as an entry criterion for extracorporeal membrane oxygenation (ECMO) in neonates with several forms of acute respiratory insufficiency. Although for meconium aspiration syndrome, respiratory distress syndrome, sepsis, and idiopathic pulmonary hypertension of the newborn we found values in accordance with the literature, patients with congenital diaphragmatic hernia (CDH) met 80% mortality criteria with significant lower AaDO 2 values. Several patients died before ever reaching usual entry criteria for ECMO, because serious lung deterioration makes AaDO 2 values unreliable. Awaiting classical ECMO entry criteria for patients with CDH may at least partially explain the lower survival rate for ECMO in CDH.

Clinical use of extracorporeal membrane oxygenation in the treatment of persistent pulmonary hypertension following surgical repair of congenital diaphragmatic hernia

The clinical use of extracorporeal membrane oxygenation (ECMO) in the treatment of persistent pulmonary hypertension following surgical repair of congenital diaphragmatic hernia is reported on 11 patients. The patients had a total of 13 treatments; two patients had two treatments. During the same period of clinical use, 122 patients were placed on ECMO for all causes. The indications, results, and complications of the use of ECMO for treatment following surgical repair of congenital diaphragmatic hernia are presented. The reversal of persistent pulmonary hypertension is demonstrated. All patients treated by ECMO for congenital diaphragmatic hernia have survived.