Extracorporeal membrane oxygenation (ECMO) in neonatal respiratory failure. 100 cases

The role of extracorporeal life support and timing of repair in infants with congenital diaphragmatic hernia

Extracorporeal life support (ECLS) serves as a rescue therapy for patients with congenital diaphragmatic hernia (CDH) and severe cardiopulmonary failure, and only half of these patients survive to discharge. This costly intervention has a significant complication risk and is reserved for patients with the most severe disease physiology refractory to maximal cardiopulmonary support. Some contraindications to ECLS do exist such as coagulopathy, lethal chromosomal or congenital anomaly, very preterm birth, or very low birth weight, but many of these limits are being evaluated through further research. Consensus guidelines from the past decade vary in recommendations for ECLS use in patients with CDH but this therapy appears to have a survival benefit in the most severe subset of patients. Improved outcomes have been observed for patients treated at high-volume centers. This review details the evolving literature surrounding management paradigms for timing of CDH repair for patients receiving preoperative ECLS. Most recent data support early repair following cannulation to avoid non-repair which is uniformly fatal in this population. Longer ECLS runs are associated with decreased survival, and patient physiology should guide ECLS weaning and eventual decannulation rather than limiting patients to arbitrary run lengths. Standardization of care across centers is a major focus to limit unnecessary costs and improve short-term and long-term outcomes for these complex patients.

Dose optimization and target attainment of vancomycin in children

Vancomycin is a glycopeptide antibiotic that has been adopted in clinical practice to treat gram-positive infections for more than 70 years. Despite vancomycin's long history of therapeutic use, optimal dose adjustments and pharmacokinetic/pharmacodynamic (PK/PD) target attainment in children are still under debate. Therapeutic drug monitoring (TDM) has been widely integrated into pediatric clinical practice to maximize efficacy and safety of vancomycin treatment. Area under the curve (AUC)-guided TDM has been recently recommended instead of trough-only TDM to ensure PK/PD target attainment of AUC0-24h/minimal inhibitory concentration (MIC) > 400 to 600 and minimize acute kidney injury risk. Bayesian forecasting in pediatric patients allows estimation of population PK to accurately predict individual vancomycin concentrations over time, and consequently total vancomycin exposure. AUC-guided TDM for vancomycin, preferably with Bayesian forecasting, is therefore suggested for all pediatric age groups and special pediatric populations. In this review we aim to analyze the current literature on the pediatric use of vancomycin and summarize the current knowledge on dosing optimization for target attainment in special patient populations.

The History of Extracorporeal Membrane Oxygenation and the Development of Extracorporeal Membrane Oxygenation Anticoagulation

Extracorporeal membrane oxygenation (ECMO) was first started for humans in early 1970s by Robert Bartlett. Since its inception, there have been numerous challenges with extracorporeal circulation, such as coagulation and platelet activation, followed by consumption of coagulation factors and platelets, and biocompatibility of tubing, pump, and oxygenator. Unfractionated heparin (heparin hereafter) has historically been the defacto anticoagulant until recently. Also, coagulation monitoring was mainly based on bedside activated clotting time and activated partial thromboplastin time. In the past 50 years, the technology of ECMO has advanced tremendously, and thus, the survival rate has improved significantly. The indication for ECMO has also expanded. Among these are clinical conditions such as postcardiopulmonary bypass, sepsis, ECMO cardiopulmonary resuscitation, and even severe coronavirus disease 2019 (COVID-19). Not surprisingly, the number of ECMO cases has increased according to the Extracorporeal Life Support Organization Registry and prolonged ECMO support has become more prevalent. It is not uncommon for patients with COVID-19 to be on ECMO support for more than 1 year until recovery or lung transplant. With that being said, complications of bleeding, thrombosis, clot formation in the circuit, and intravascular hemolysis still remain and continue to be major challenges. Here, several clinical ECMO experts, including the "Father of ECMO"-Dr. Robert Bartlett, describe the history and advances of ECMO.

Extracorporeal Membrane Oxygenation Then and Now; Broadening Indications and Availability

Extracorporeal membrane oxygenation (ECMO) is a life support technology provided to children to support respiratory failure, cardiac failure, or cardiopulmonary resuscitation after failure of conventional management. Over the decades, ECMO has expanded in use, advanced in technology, shifted from experimental to a standard of care, and evidence supporting its use has increased. The expanded ECMO indications and medical complexity of children have also necessitated focused studies in the ethical domain such as decisional authority, resource allocation, and equitable access.

The next generation of evidence-based medicine

Recently, advances in wearable technologies, data science and machine learning have begun to transform evidence-based medicine, offering a tantalizing glimpse into a future of next-generation 'deep' medicine. Despite stunning advances in basic science and technology, clinical translations in major areas of medicine are lagging. While the COVID-19 pandemic exposed inherent systemic limitations of the clinical trial landscape, it also spurred some positive changes, including new trial designs and a shift toward a more patient-centric and intuitive evidence-generation system. In this Perspective, I share my heuristic vision of the future of clinical trials and evidence-based medicine.

Expanding neonatal ECMO criteria: When is the premature neonate too premature

Extracorporeal membrane oxygenation (ECMO) is a universally accepted and life-saving therapy for neonates with respiratory or cardiac failure that is refractory to maximal medical management. Early studies found unacceptable risks of mortality and morbidities such as intracranial hemorrhage among premature and low birthweight neonates, leading to widely accepted ECMO inclusion criteria of gestational age ≥34 weeks and birthweight >2 kg. Although contemporary data is lacking, the most recent literature demonstrates increased survival and decreased rates of intracranial hemorrhage in premature neonates who are supported with ECMO. As such, it seems like the right time to push the boundaries of ECMO on a case-by-case basis beginning with neonates 32-34 weeks GA in large volume centers with careful neurodevelopmental follow-up to better inform practices changes on this select population.

Extracorporeal membrane oxygenation in COVID-19 associated acute respiratory distress syndrome: A narrative review

Venovenous extracorporeal membrane oxygenation (VV-ECMO) is an established rescue therapy in the management of refractory acute respiratory distress syndrome (ARDS). Although ECMO played an important role in previous respiratory viral epidemics, concerns about the benefits and usefulness of this technique were raised during the coronavirus disease 2019 (COVID-19) pandemic. Indeed, the mortality rate initially reported in small case series from China was concerning and exceeded 90%. A few months later, the critical care community published the findings from several observational cohorts on the use of extracorporeal membrane oxygenation (ECMO) in COVID-19-related ARDS. Contrary to the preliminary results, data from the first surge supported the use of ECMO in experienced centers because the mortality rate was comparable to those from the ECMO to Rescue Lung Injury in Severe ARDS (EOLIA) trial or other large prospective studies. However, the mortality rate of the population with severe disease evolved during the pandemic, in conjunction with changes in the management of the disease and the occurrence of new variants. The results from subsequent studies confirmed that the outcomes mainly depend on strict patient selection and center expertise. In comparison with non-COVID-related ARDS, the duration of ECMO for COVID-related ARDS was longer and increased over time. Clinicians and decision-makers must integrate this finding in the ECMO decision-making process to plan their ICU capacity and resource allocation. This narrative review summarizes the current evidence and specific considerations for ECMO use in COVID-19-associated ARDS.

Premature and Extracorporeal Life Support: Is it Time? A Systematic Review

Early preterm birth < 34 gestational weeks (GA) and birth weight (BW) <2 kg are relative contraindications for extracorporeal membrane oxygenation (ECMO). However, with improved technology, ECMO is presently managed more safely and with decreasing complications. Thus, these relative contraindications may no longer apply. We performed a systematic review to evaluate the existing literature on ECMO in early and late (34-37 GA) prematurity focusing on survival to hospital discharge and the complication intracranial hemorrhage (ICH). Data sources: MEDLINE, PubMed, Web of Science, Embase, and the Cochrane Database. Only publications in the English language were evaluated. Of the 36 included studies, 23 were related to ECMO support for respiratory failure, 10 for cardiac causes, and four for congenital diaphragmatic hernia (CDH). Over the past decades, the frequency of ICH has declined (89-21%); survival has increased in both early prematurity (25-76%), and in CDH (33-75%), with outcome similar to late prematurity (48%). The study was limited by an inherent risk of bias from overlapping single-center and registry data. Both the risk of ICH and death have decreased in prematurely born treated with ECMO. We challenge the 34 week GA time limit for ECMO and propose an international task force to revise current guidelines. At present, gestational age < 34 weeks might no longer be considered a contraindication for ECMO in premature neonates.

Trends in the Extracorporeal Membrane Oxygenation Literature: A Bibliometric Analysis in the COVID-19 Era

Extracorporeal Membrane Oxygenation (ECMO) was first used in the 1970s. Its use is increasingly common in critical care and perioperative settings and has gained newfound prominence during COVID-19. To guide future research, we conducted a bibliometric analysis of ECMO literature. Thomson Reuters Web of Science was searched to March 7, 2021. Articles were ranked by total number of citations. Data was extracted from the 100 most cited papers relevant to ECMO for study design, topic, author, year, and institution. Journal impact factor for 2019 and Eigenfactor scores were also recorded. Our search retrieved a total of 18,802 articles. Median number of citations for the top 100 articles was 220 (range 157-1,819). These were published in 34 journals, with first authors originating from 15 countries. The Annals of Thoracic Surgery had the highest number of articles (n = 9) while Lancet publications had the most citations (n = 3,191). Use of ECMO was most commonly observed in cardiogenic shock or acute respiratory distress syndrome. United States had the greatest article output (n = 49). With 10 publications, 2013 was the most prolific year. Using linear regression, when controlled for time since publication, there was no statistically significant relationship between 2019 journal impact factor and number of article citations (p = .09). Top articles in the ECMO literature are of considerable impact and quality. As the United States produced the bulk of the prominent evidence base, and most data were regarding respiratory issues, outsized advances in ECMO may be possible within the United States during the COVID-19 era.

Unité mobile d’assistance circulatoire et respiratoire de l’enfant et du nouveau-né : une revue narrative

Les unités mobiles d’assistance circulatoire et respiratoire de l’enfant et du nouveau-né se sont développées au cours des dix dernières années. En effet, la mise en place d’une suppléance extracorporelle respiratoire ou circulatoire nécessite une équipe expérimentée et n’est pas disponible dans tous les centres hospitaliers pédiatriques. Or, les enfants atteints d’une défaillance circulatoire ou respiratoire réfractaire ne sont, pour la plupart, pas déplaçables vers une unité délivrant ce type de traitement de sauvetage. Les unités mobiles ont donc pour objectif de mettre à disposition ces technologies d’exception sur l’ensemble du territoire afin de garantir une égalité d’accès aux soins. Cependant, la haute technicité de ces thérapeutiques nécessite une équipe entraînée sachant poser et régler une assistance extracorporelle, prendre en charge un patient en défaillance respiratoire et/ou hémodynamique réfractaire et aguerrie à ces transports à haut risque. Le territoire français était jusqu’en 2014 très mal couvert par les unités mobiles pédiatriques et néonatales. Depuis, la création de plusieurs unités a permis une couverture totale du territoire. L’objectif de cette revue narrative sur les unités mobiles pédiatriques et néonatales est de résumer les différentes modalités de suppléance respiratoire et hémodynamique extracorporelle, d’en illustrer leurs différentes missions et leurs modalités de fonctionnement. Nous finirons par une description de leur efficacité en termes de survie et de survenue d’incidents en cours de transport.

Membrane Lung and Blood Pump Use During Prolonged Extracorporeal Membrane Oxygenation: Trends From 2002 to 2017

Extracorporeal life support (ECLS) has grown in its application since its first clinical description in the 1970s. The technology has been used to support a wide variety of mechanical support modalities and diseases, including respiratory failure, cardiorespiratory failure, and cardiac failure. Over many decades and safety and efficacy studies, followed by randomized clinical trials and thousands of clinical uses, ECLS is considered as an accepted treatment option for severe pulmonary and selected cardiovascular failure. Extracorporeal life support involves the use of support artificial organs, including a membrane lung and blood pump. Over time, changes in the technology and the management of ECLS support devices have evolved. This manuscript describes the use of membrane lungs and blood pumps used during ECLS support from 2002 to 2017 in over 65,000 patients reported to the Extracorporeal Life Support Organization Registry. Device longevity and complications associated with membrane lungs and blood pump are described and stratified by age group: neonates, pediatrics, and adults.

Extracorporeal Membrane Oxygenation in Pediatric Liver Transplantation: A Multicenter Linked Database Analysis and Systematic Review of the Literature

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) can be used to maintain oxygen delivery and provide hemodynamic support in case of circulatory and respiratory failure. Although the role of ECMO has emerged in the setting of adult liver transplantation (LT), data in children are limited. We aimed to describe the characteristics and outcomes of children receiving ECMO support at the time of or following LT.

METHODS

All pediatric LT recipients (≤20 y) requiring ECMO support peri-/post-LT were identified from a linked Pediatric Health Information System/Scientific Registry of Transplant Recipients dataset (2002-2018). The Kaplan-Meier method and Cox regression analysis were used to assess post-ECMO survival. A systematic literature review was conducted in accordance with the PRISMA statement.

RESULTS

Thirty-four children required ECMO peri-/post-LT. The median time from LT to ECMO was 5 d (interquartile range, 0.0-12.3), and the median ECMO duration was 1 d (interquartile range, 1.0-6.3). Children started on ECMO within 1 d of LT exhibited superior survival compared with those started on ECMO later (P = 0.03). When adjusting for recipient weight, increasing time from LT to ECMO initiation was associated with increased risk of mortality (hazard ratio, 1.03; 95% confidence interval, 1.00-1.06; P = 0.049). Overall, 55.9% (n = 19 of 34) of the patients survived. Twenty-two children receiving ECMO in the peri-/post-LT period were systematically reviewed, and 15 of them survived (68.2%).

CONCLUSIONS

With an encouraging >55% patient survival at 6 mo, ECMO should be considered as a viable option in pediatric LT recipients with potentially reversible severe respiratory or cardiovascular failure refractory to conventional treatment.

Bioengineering Progress in Lung Assist Devices

Artificial lung technology is advancing at a startling rate raising hopes that it would better serve the needs of those requiring respiratory support. Whether to assist the healing of an injured lung, support patients to lung transplantation, or to entirely replace native lung function, safe and effective artificial lungs are sought. After 200 years of bioengineering progress, artificial lungs are closer than ever before to meet this demand which has risen exponentially due to the COVID-19 crisis. In this review, the critical advances in the historical development of artificial lungs are detailed. The current state of affairs regarding extracorporeal membrane oxygenation, intravascular lung assists, pump-less extracorporeal lung assists, total artificial lungs, and microfluidic oxygenators are outlined.

Antifactor Xa Monitoring and Hematologic Complications of Pediatric Extracorporeal Membrane Oxygenation

Hemorrhagic and thrombotic complications are a significant source of morbidity and mortality for pediatric patients on extracorporeal membrane oxygenation (ECMO). Optimal anticoagulation therapies and monitoring strategies remain unknown. In 2013, our institution changed the anticoagulation monitoring protocol from activated clotting time (ACT) to antifactor Xa (anti-Xa) levels. We conducted a retrospective review of patients who received anticoagulation management directed by ACT results (n = 96) or anti-Xa levels (n = 72) between January 2010 and March 2016. Hemorrhagic complications occurred in 25% of the ACT group and 39% of the anti-Xa group (p = 0.054). Thrombotic complications were observed in 12.5% of the ACT group and 14% of the anti-Xa group (p = 0.8). There was a greater incidence of extracorporeal cardiopulmonary resuscitations (E-CPR; 36% vs. 15%; p = 0.005) in the anti-Xa group as compared with the ACT group. Secondary analysis showed no difference in transfusion requirements for red blood cells (ml/kg; p = 0.32) or platelets (ml/kg; p = 0.32). There was no difference in average heparin infusion rates (unit/kg/hr) per cannulation (p = 0.17) between the groups. Management of anticoagulation based on anti-Xa levels appears to be as effective as management based on ACT results.

Extracorporeal membrane oxygenation and lung transplantation

The use of extracorporeal membrane oxygenation has had a positive impact on the outcomes after lung transplantation. Extracorporeal membrane oxygenation has a role in all phases of lung transplantation-preoperative, intraoperative, and postoperative periods. It serves as a bridge to transplantation in appropriate patients awaiting lung transplantation. Extracorporeal membrane oxygenation is used as a preferred method of cardiopulmonary support in some centres during implantation; and, after lung transplantation, it can be used to salvage the implanted lung in cases of severe primary graft dysfunction or as a planned extension of intraoperative extracorporeal membrane oxygenation onto the postoperative period. It has now gained acceptance as a mandatory tool in most lung transplant units. This article reviews the history of extracorporeal membrane oxygenation and lung transplantation, their subsequent development, and the current use of extracorporeal membrane oxygenation during lung transplantation. Our institutional practice and experience are described. The implications of the current global coronavirus disease pandemic on extracorporeal membrane oxygenation and lung transplantation are also briefly discussed.

Extracorporeal Gas Exchange for Acute Respiratory Distress Syndrome: Open Questions, Controversies and Future Directions

Veno-venous extracorporeal membrane oxygenation (V-V ECMO) in acute respiratory distress syndrome (ARDS) improves gas exchange and allows lung rest, thus minimizing ventilation-induced lung injury. In the last forty years, a major technological and clinical improvement allowed to dramatically improve the outcome of patients treated with V-V ECMO. However, many aspects of the care of patients on V-V ECMO remain debated. In this review, we will focus on main issues and controversies on caring of ARDS patients on V-V ECMO support. Particularly, the indications to V-V ECMO and the feasibility of a less invasive extracorporeal carbon dioxide removal will be discussed. Moreover, the controversies on management of mechanical ventilation, prone position and sedation will be explored. In conclusion, we will discuss evidences on transfusions and management of anticoagulation, also focusing on patients who undergo simultaneous treatment with ECMO and renal replacement therapy. This review aims to discuss all these clinical aspects with an eye on future directions and perspectives.

Neurodevelopmental outcomes in children with isolated congenital diaphragmatic hernia: A systematic review and meta-analysis

BACKGROUND

Congenital diaphragmatic hernia (CDH) reportedly has neurologic consequences in childhood however little is known about the impact in isolated CDH.

AIMS

Herein we aimed to describe the risk of neurodevelopmental complications in children born with isolated CDH.

MATERIALS & METHODS

We systematically reviewed literature for reports on the neurological outcome of infants born with isolated CDH. The primary outcome was neurodevelopmental delay. Secondary outcomes included, motor skills, intelligence, vision, hearing, language and behavior abnormalities.

RESULTS

Thirteen out of 87 (15%) studies reported on isolated CDH, including 2624 out of 24,146 children. Neurodevelopmental delay was investigated in four studies and found to be present in 16% (3-34%) of children. This was mainly attributed to motor problems in 13% (2-30%), whereas cognitive dysfunction only in 5% (0-20%) and hearing in 3% (1-7%). One study assessed the effect of fetal surgery. When both isolated and non-isolated children were included, these numbers were higher.

DISCUSSION

This systematic review demonstrates that only a minority of studies focused on isolated CDH, with neurodevelopmental delay present in 16% of children born with CDH.

CONCLUSION

To accurately counsel patients, more research should focus on isolated CDH cases and examine children that underwent fetal surgery.

Reconsidering ECMO in Premature Neonates

Extracorporeal membrane oxygenation (ECMO) is a life-saving intervention for neonates with respiratory failure or congenital cardiac disease refractory to maximal medical management. Early studies showed high rates of mortality and morbidities among preterm and low birthweight (BW) neonates, leading to widely accepted ECMO inclusion criteria of gestational age (GA) ≥34 weeks and BW >2 kg. In recent years, publications involving neonates of 32-34 weeks GA have reported improved survival and decreased intracranial hemorrhage. As such, ECMO should be considered on a case-by-case basis in premature neonates as long as the risks are understood.

Decreased Brain Volumes and Infants With Congenital Heart Disease Undergoing Venoarterial Extracorporeal Membrane Oxygenation

OBJECTIVES

The aims of this study were to: i) determine the spectrum of brain injury and ii) compare brain volumes between pre- and postoperative brain MRI in the infants receiving extracorporeal membrane oxygenation compared with those who did not require extracorporeal membrane oxygenation.

DESIGN

Cohort study of infants with D-transposition of the great arteries or single ventricle physiology. Brain volume (cm) was measured using a segmentation of a volumetric T1-weighted gradient echo sequence. Brain imaging findings (intraventricular hemorrhage, white matter injuries, and stroke) were analyzed with respect to known clinical risk factors for brain injury and adverse neurodevelopmental outcomes. Clinical factors were collected by retrospective chart review. The association between brain volume and extracorporeal membrane oxygenation was evaluated using generalized estimating equations to account for repeated measures.

SETTING

Prospective and single-centered study.

PATIENTS

One hundred nine infants (median gestational age, 39.1 wk) with D-transposition of the great arteries (n = 77) or single ventricle physiology (n = 32) were studied pre- and postoperatively with MRI as per clinical protocol.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 28 infants (26%) receiving extracorporeal membrane oxygenation, 19 (68%) were supported with extracorporeal membrane oxygenation once, and nine (32%) were supported 2-4 times. On postoperative MRI, new white matter injury was found in only five (17%) of the extracorporeal membrane oxygenation infants versus 40 (49%) in the non-extracorporeal membrane oxygenation group (p = 0.073). The rate of stroke (9% vs 10%), intraventricular hemorrhage (24% vs 29%), and hypoxic ischemia (3% vs 14%) did not differ between the non-extracorporeal membrane oxygenation and extracorporeal membrane oxygenation groups (all p > 0.5). Accounting for D-transposition of the great arteries or single ventricle physiology diagnosis, infants requiring extracorporeal membrane oxygenation had slower brain volume with single (β = -1.67) or multiple extracorporeal membrane oxygenation runs ([β = -6.54]; overall interaction p = 0.012).

CONCLUSIONS

Patients with d-transposition of the great arteries or single ventricle physiology undergoing extracorporeal membrane oxygenation at our center have a similar incidence of brain injury but more significant impairment of perioperative brain volumes than those not requiring extracorporeal membrane oxygenation.

Extracorporeal Membrane Oxygenation Support for Pediatric Burn Patients: Is It Worth the Risk?

OBJECTIVES

Examine the outcomes of pediatric burn patients requiring extracorporeal membrane oxygenation to determine whether extracorporeal membrane oxygenation should be considered in this special population.

DESIGN

Retrospective cohort study.

SETTING

All extracorporeal membrane oxygenation centers reporting to the Extracorporeal Life Support Organization.

SUBJECTS

Pediatric patients (birth to younger than 18 yr) who were supported with extracorporeal membrane oxygenation with a burn diagnosis between 1990 and 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 113 patients were identified from the registry by inclusion criteria. Patients cannulated for respiratory failure had the highest survival (55.7%, n = 97) compared to those supported for cardiac failure (33.3%, n = 6) or extracorporeal cardiopulmonary resuscitation (30%, n = 10). Patients supported on venovenous extracorporeal membrane oxygenation for respiratory failure had the best overall survival at 62.2% (n = 37). Important for the burn population, rates of surgical site bleeding were similar to other surgical patients placed on extracorporeal membrane oxygenation at 22.1%. Cardiac arrest prior to cannulation was associated with increased hospital mortality (odds ratio, 3.41; 95% CI, 0.16-1.01; p = 0.048). Following cannulation, complications including the need for inotropes (odds ratio, 2.64; 95% CI, 1.24-5.65; p = 0.011), presence of gastrointestinal hemorrhage (p = 0.049), and hyperglycemia (glucose > 240 mg/dL) (odds ratio, 3.42; 95% CI, 1.13-10.38; p = 0.024) were associated with increased mortality. Of patients with documented burn percentage of total body surface area (n = 19), survival was 70% when less than 60% total body surface area was involved.

CONCLUSIONS

Extracorporeal membrane oxygenation could be considered as an additional level of support for the pediatric burn population, especially in the setting of respiratory failure. Additional studies are necessary to determine the optimal timing of cannulation and other patient characteristics that may impact outcomes.

Overview of the bicaval dual lumen cannula

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is a form of extracorporeal life support that provides total gas exchange (CO2 and O2) within the central venous circulation. The bicaval dual lumen cannula (DLC) is an option for patients requiring respiratory support with VV-ECMO. The catheter is inserted via the internal jugular vein into the superior and inferior vena cava, drains blood into the ECMO circuit for gas exchange, and then returns arterialized blood to the right heart for circulation. The DLC facilitates physical therapy, ambulation, and early extubation. This chapter will review the uses, advantages, and unique complications of the DLC.

Neonatal respiratory extracorporeal membrane oxygenation and primary diagnosis: trends between two decades

OBJECTIVE

Examine changing neonatal respiratory extracorporeal membrane oxygenation (ECMO) practice trends and outcomes.

STUDY DESIGN

Retrospective cohort study comparing neonatal respiratory ECMO in the 1990 and 2010 decades (1994-1995 and 2014-2015). Patients ≤ 30 days of life, reported to the Extracorporeal Life Support Organization registry, were included.

RESULTS

Four thousand one hundred and twenty-five patients met inclusion criteria. ECMO cases decreased by 33%. The primary ECMO diagnosis changed significantly over time (p < 0.0001). Survival to discharge decreased (76 vs 67%, p < 0.0001) and ECMO duration increased (131 vs 158 h, p < 0.001). Lung recovery was the most common reason to discontinue ECMO although family request for withdrawal and a diagnosis considered "incompatible with life" was increasingly common in the 2010s.

CONCLUSION

Although the use of ECMO for neonatal respiratory diagnoses has decreased over time, its use has increased for patients with more complex diagnoses and ECMO duration is longer. ECMO continues to be an important supportive therapy, improved understanding of which patients would benefit most is needed.

Development and Validation of Extracorporeal Membrane Oxygenation Mortality-Risk Models for Congenital Diaphragmatic Hernia

The purpose of our study was to develop and validate extracorporeal membrane oxygenation (ECMO)–specific mortality risk models for congenital diaphragmatic hernia (CDH). We utilized the data from the Extracorporeal Life Support Organization Registry (2000–2015). Prediction models were developed using multivariable logistic regression. We identified 4,374 neonates with CDH with an overall mortality of 52%. Predictive discrimination (C statistic) for pre-ECMO mortality model was C = 0.65 (95% confidence interval, 0.62–0.68). Within the highest risk group, based on the pre-ECMO risk score, mortality was 87% and 75% in the training and validation data sets, respectively. The pre-ECMO risk score included pre-ECMO ventilator settings, pH, prior diaphragmatic hernia repair, critical congenital heart disease, perinatal infection, and demographics. For the on-ECMO model, mortality prediction improved substantially: C = 0.73 (95% confidence interval, 0.71–0.76) with the addition of on-ECMO–associated complications. Within the highest risk group, defined by the on-ECMO risk score, mortality was 90% and 86% in the training and validation data sets, respectively. Mortality among neonates with CDH needing ECMO can be reliably predicted with validated clinical variables identified in this study. ECMO-specific mortality prediction tools can allow risk stratification to be used in research and quality improvement efforts, as well as with caution for individual case management.

Cerebral Oxygenation of Premature Lambs Supported by an Artificial Placenta

An artificial placenta (AP) using venovenous extracorporeal life support (VV-ECLS) could represent a paradigm shift in the treatment of extremely premature infants. However, AP support could potentially alter cerebral oxygen delivery. We assessed cerebral perfusion in fetal lambs on AP support using near-infrared spectroscopy (NIRS) and carotid arterial flow (CAF). Fourteen premature lambs at estimated gestational age (EGA) 130 days (term = 145) underwent cannulation of the right jugular vein and umbilical vein with initiation of VV-ECLS. An ultrasonic flow probe was placed around the right carotid artery (CA), and a NIRS sensor was placed on the scalp. Lambs were not ventilated. CAF, percentage of regional oxygen saturation (rSO2) as measured by NIRS, hemodynamic data, and blood gases were collected at baseline (native placental support) and regularly during AP support. Fetal lambs were maintained on AP support for a mean of 55 ± 27 hours. Baseline rSO2 on native placental support was 40% ± 3%, compared with a mean rSO2 during AP support of 50% ± 11% (p = 0.027). Baseline CAF was 27.4 ± 5.4 ml/kg/min compared with an average CAF of 23.7 ± 7.7 ml/kg/min during AP support. Cerebral fractional tissue oxygen extraction (FTOE) correlated negatively with CAF (r = -0.382; p < 0.001) and mean arterial pressure (r = -0.425; p < 0.001). FTOE weakly correlated with systemic O2 saturation (r = 0.091; p = 0.017). Cerebral oxygenation and blood flow in premature lambs are maintained during support with an AP. Cerebral O2 extraction is inversely related to carotid flow and is weakly correlated with systemic O2 saturation.

Vancomycin pharmacokinetics in critically ill neonates receiving extracorporeal membrane oxygenation

Objective

This study aimed to characterise vancomycin pharmacokinetics in critically ill neonates undergoing extracorporeal membrane oxygenation.

Methods

In a retrospective analysis, the pharmacokinetics of vancomycin were determined in 25 full-term neonates receiving extracorporeal membrane oxygenation and compared with those of matched controls (n = 25) not receiving extracorporeal membrane oxygenation.

Results

The half-life of vancomycin in the neonates undergoing extracorporeal membrane oxygenation was significantly prolonged compared with that in the controls (17.45 ± 11.01 hour vs 5.92 ± 2.70 hour, P<0.001). Clearance decreased significantly in the extracorporeal membrane oxygenation group relative to the control group (0.03 ± 0.02 L/kg/hr vs 0.08 ± 0.05 L/kg/hr, P<0.001). No significant difference was found in the volume of distribution between the two groups (0.63 ± 0.30 L/kg in the extracorporeal membrane oxygenation group vs 0.57 ± 0.14 L/kg/hr in control, P=0.596). Clearance values were significantly correlated with serum creatinine (r = - 0.528, P<0.001). In the subgroup analysis using patients with serum creatinine < 0.5 mg/dL, similar results were obtained including significantly prolonged half-life (11.52 ± 6.31 hour vs 5.44 ± 2.36 hour, P<0.001) and decreased clearance (0.05 ± 0.02 L/kg/hr vs 0.09 ± 0.05 L/kg/hr, P<0.001) in the extracorporeal membrane oxygenation group relative to the control group.

Conclusions

Vancomycin clearance decreased significantly in the neonates undergoing extracorporeal membrane oxygenation compared with the controls. Dosing adjustments of vancomycin and close therapeutic drug monitoring are required for the safe and effective management of neonates during extracorporeal membrane oxygenation.

The quality of life in extracorporeal life support survivors: single-center experience of a long-term follow-up

OBJECTIVE

To evaluate the health-related quality of life on a very long-term follow-up in patients treated with extracorporeal membrane oxygenation (ECMO) during neonatal and pediatric age.

DESIGN

Prospective follow-up study.

SETTING

Pediatric Intensive Care Unit of a tertiary-care University-Hospital.

PATIENTS

Out of 20 neonates and 21 children treated with ECMO in our center, 24 patients underwent short-term neurological follow-up. Twenty of them underwent long-term neurological follow-up.

INTERVENTION

Short-term follow-up was performed at 18 months and consisted in clinical evaluation, electroencephalography, and neuroimaging. Long-term follow-up was performed in 2017, at the mean period 19.72 years from ECMO (median 20.75, range 11.50-24.08) and consisted in a standardized questionnaires self-evaluation (PedsQL 4.0 Generic Core Scale) of health-related quality of life and an interviewed about the presence of organ morbidity, school level, or work position.

MEASUREMENTS AND MAIN RESULTS

Sixty-one percent (25/41) of the patients survived within 30 days after ECMO treatment. Short-term follow-up was performed in 24 patients (1 patient but died before the evaluation): 21 patients (87%) showed a normal neurological status, and 3 developed severe disability. Long-term follow-up was performed in 20 long-term survivors (3 patients were not possible to be contacted and considered lost to follow-up): mean age of patients at long-term follow-up was 21.23 (median 20.96, range 13.33-35.58) years; 90% (18/20) of them have no disability with a complete normal quality of life and 95% have no cognitive impairment.

CONCLUSIONS

ECMO represents a life-saving treatment for infants and children with respiratory and/or heart failure; survivors show a good quality of life comparable to healthy peers.

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.

Interhospital Transport on Extracorporeal Membrane Oxygenation of Neonates-Perspective for the Future

In recent years the number of extracorporeal membrane oxygenation (ECMO) cases in neonates has been relatively constant. Future expansion lays in new indications for treatment. Regionalization to high-volume ECMO centers allows for optimal utilization of resources, reduction in costs, morbidity, and mortality. Mobile ECMO services available "24-7" are needed to provide effective logistics and reliable infrastructure for patient safety. ECMO transports are usually high-risk and complex. To reduce complications during ECMO transport communication using time-out, checklists, and ECMO A-B-C are paramount in any size mobile program. Team members' education, clinical training, and experience are important. For continuing education, regular wet-lab training, and simulation practices in teams increase performance and confidence. In the future the artificial placenta for the extremely premature infant (23-28 gestational weeks) will be introduced. This will enforce the development and adaptation of ECMO devices and materials for increased biocompatibility to manage the high-risk prem-ECMO (28-34 weeks) patients. These methods will likely first be introduced at a few high-volume neonatal ECMO centers. The ECMO team brings bedside competence for assessment, cannulation, and commencement of therapy, followed by a safe transport to an experienced ECMO center. How transport algorithms for the artificial placentae will affect mobile ECMO is unclear. ECMO transport services in the newborn should firstly be an out-reach service led and provided by ELSO member centers that continuously report transport data to an expansion of the ELSO Registry to include transport quality follow-up and research. For future development and improvement follow-up and sharing of data are important.

Mechanical Support of the Left Ventricle in Ischemia Induced Left Ventricular Failure: An Experimental Study

Objective

this study compares the hemodynamic effects of intraaortic balloon pumping (IABP), left ventricular assist device (LVAD), and extracorporeal membrane oxygenation (ECMO) in left ventricular failure in pigs.

Methods

In 29 pigs weighing 12 + 0.7 kg left ventricular failure was induced by ligating the left anterior descending coronary artery. Eight animals served as controls. Eight pigs were treated by IABP, seven by LVAD, and six by ECMO. The study period lasted four hours. Hemodynamic and oxygen transport/ uptake parameters were measured continuously or intermittently.

Results

Six animals of the ECMO and LVAD groups survived the 4 hour period, but only 3 and 4 animals of the IABP and control groups survived (p<0.05). Cardiac index decreased about 48% and 22% in the control and IABP groups (p<0.05), whereas there was only a slight decrease in the ECMO (9%) and LVAD (14%) groups. Oxygen delivery fell significantly in the control and IABP groups (p<0.05), compared with only a slight change in the LVAD and ECMO groups.

Conclusion

ECMO is the most effective system for temporary circulatory support in severe ventricular failure. LVAD maintains cardiac output when pulmonary blood flow is provided. IABP is less efficient in supporting the failing heart, especially in the presence of severe ventricular arrhythmias.

Follow-up in Neonatal Extracorporeal Membrane Oxygenation (ECMO)

In 34 survivors of the first 43 ECMO patients from our institution before discharge to another hospital or home an EEG, BAER, Head Ultrasonography, cerebral CT scan, Dubowitz score and ophthalmological inspection were performed. At one year of age Mental Developmental Index of the Bayley scales, Motor Quotient as well as pulmonary and neurological status were assessed. In 29 patients follow-up took place in our hospital. In 17 of them (59%) all tests before discharge were normal, 2 patients (7%) showed an abnormal BAER, an additional 5 patients (17%) had abnormal EEG and 2 patients (7%) had abnormal HUS in combination with abnormal cerebral CT scan. In 19 patients (33%) the Dubowitz score was abnormal at discharge. At one year of age neurological status was normal in 25 (86%) patients, respiratory status was normal in 22 (76%) and Mental Development Index was > 80 in 23 of the patients (79%). A significant correlation between Mental Development Index and Motor Quotient was found r=0.50, p=0.0065. It is concluded that more than one abnormal neurophysiological test before discharge may identify patients with additional risks for adverse outcome and that the respiratory status influenced psychomotor development at one year of age.

Blood Platelet Activation and Membrane Glycoprotein Changes during Extracorporeal Life Support (Ecls). In Vitro Studies

The aim of this study was to evaluate an in vitro model for investigation of platelet function parameters in an extracorporeal system. Two different perfusion pumps were compared, a roller pump (Polystan) and a centrifugal pump (Biomedicus). A continuous increase in glycoprotein (GP)1b-negative platelets was observed in both circuits. A marked increase of plasma β-thromboglobulin thromboglobulin concentration and a decrease of the intracellular pool of serotonin was observed, indicating a marked release of alpha as well as of dense granules. The plasma concentration of glycocalicin increased in parallel with a reduced platelet surface expression of GP1b, suggesting that the loss of GP1b is caused by proteolysis rather than by a downregulation of this receptor protein. It is concluded that ECLS results in a pronounced platelet degranulation and causes changes of important membrane receptors which might explain some of the bleeding problems observed in patients treated with ECLS. No significant difference was noted between the roller pump and the centrifugal pump. Trial of strategies, e.g. protease inhibitors and nitric oxide to revert this untoward effect of ECLS are highly warranted.

Pushing the boundaries of ECLS: Outcomes in <34 week EGA neonates

PURPOSE

Extracorporeal life support (ECLS) is usually reserved for infants ≥34weeks estimated gestational age (EGA) owing to concerns about increased mortality and incidence of intracranial hemorrhage (ICH). We sought to characterize survival, rates of ICH, and complications in <34week EGA neonates placed on ECLS.

METHODS

752 neonates of EGA 29-34weeks were identified in the Extracorporeal Life Support Organization (ELSO) Registry (1976-2008). Data analyzed included birthweight, survival, pre-ECLS conditions, ventilatory parameters and complications (including ICH and other neurological outcomes). Data were compared using t-test, Chi-square and logistic regression analyses.

RESULTS

When compared to survival rates of 34week EGA neonates (58%), survival was statistically different for 29-33week EGA (48%, p=0.05). No significant difference in ICH incidence was seen between the 29-33week and 34week groups (21% vs. 17%, respectively), but a significant difference was seen in the incidence of cerebral infarct between groups (22% for 29-33weeks vs. 16% for 34weeks; p=0.03). ICH and survival did not correlate with EGA during logistic regression analysis.

CONCLUSIONS

Though rates of survival and cerebral infarction were worse at 29-33weeks EGA compared with 34weeks, these differences were modest and may be clinically acceptable. This suggests that EGA<34weeks may not be an absolute contraindication to use of ECLS.

LEVEL OF EVIDENCE

III.

Extracorporeal Membrane Oxygenation Support in Neonates: A Single Medical Center Experience in Taiwan

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) was used in neonates with severe cardiopulmonary failure who failed to respond to conventional therapy. We started to apply neck venoarterial ECMO (VA-ECMO) in neonatal patients from 2000. In this study, we have focused on neonates who received ECMO support and described the current status of ECMO in neonates for both cardiac and pulmonary support and the risk factors associated with their outcomes.

METHODS

Data were retrieved from our ECMO database for the neonates (age < 28 days) who received neck VA-ECMO support from January 2005 to June 2015.

RESULTS

In total, 27 neonates, including 21 with respiratory support and six with cardiac support, were enrolled in this study. Sixteen (59.2%) patients survived to hospital discharge, and only one patient had a poor neurological outcome. The survival rate for respiratory support was 61.9% in which meconium aspiration syndrome with persistent pulmonary hypertension of a newborn had a superior outcome (11/13, 84.6%) and congenital diaphragmatic hernia had the worst outcome (4/7, 57.1%). The survival rate in the cardiac support group was only 50%. The median ECMO duration and hospital stay were 6 (1∼35.8) days and 37 (23∼232) days, respectively, for survivors. Furthermore, 11 (52.3%) neonates of 21 outborn patients were put on ECMO in other hospitals by our mobile ECMO team for respiratory support, and their survival (81.8%) was significantly better than those from in-house ECMO institution (40%).

CONCLUSION

This is the first report for ECMO in neonatal disease in Taiwan. We achieved an overall survival rate of 59.2% with good neurological outcomes in this 10-year experience. ECMO could be a useful transportation tool for critical neonates who have a poor response to ventilator support.

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.

Cannulation strategies in adult veno-arterial and veno-venous extracorporeal membrane oxygenation: Techniques, limitations, and special considerations

Extracorporeal membrane oxygenation (ECMO) refers to specific mechanical devices used to temporarily support the failing heart and/or lung. Technological advances as well as growing collective knowledge and experience have resulted in increased ECMO use and improved outcomes. Veno-arterial (VA) ECMO is used in selected patients with various etiologies of cardiogenic shock and entails either central or peripheral cannulation. Central cannulation is frequently used in postcardiotomy cardiogenic shock and is associated with improved venous drainage and reduced concern for upper body hypoxemia as compared to peripheral cannulation. These concerns inherent to peripheral VA ECMO may be addressed through so-called triple cannulation approaches. Veno-venous (VV) ECMO is increasingly employed in selected patients with respiratory failure refractory to more conventional measures. Newer dual lumen VV ECMO cannulas may facilitate extubation and mobilization. In summary, the pathology being addressed impacts the ECMO approach that is deployed, and each ECMO implementation has distinct virtues and drawbacks. Understanding these considerations is crucial to safe and effective ECMO use.

Neurological Complications of Respiratory Disease

The respiratory and central nervous systems are intimately connected. Ventilatory control is strictly regulated by central mechanisms in a complex process that involves central and peripheral chemoreceptors, baroreceptors, the cardiovascular system, and specific areas of the brain responsible for autonomic control. Disorders of the lung and respiratory system can interfere with these mechanisms and temporarily or permanently disrupt this complex network resulting in mild to severe neurological sequelae. This article explores the wide variety of neurological problems resulting from respiratory dysfunction, with emphasis on its pathophysiology, clinical features, prognosis, and long-term outcome.

Platelet consumption during neonatal extracorporeal life support (ECLS)

This paper reports the results of a retrospective study of blood use and blood loss in 40 neonates during extracorporeal life support (ECLS). Immediately after onset of bypass 39±2.5ml platelets, 59.4±6.5ml packed red blood cells (PRBC) and 15.0±5.4ml fresh frozen plasma (FFP) per patient were needed. The average daily amount given per patient was 49.0±3.0ml of platelets and 48.0±3.4ml and 9.6±3.9ml of PRBC and FFP respectively. The 10 patients who had bleeding complications received 50.0±6.3ml/day of platelets compared to 49.0±3.4ml in the other patients. The majority of blood loss during the entire period of ECLS was from samples, averaging 43.0 ± 1.5ml/day. Neck wound drainage, 6.7±2.5ml/day per patient, lasted for the entire period.

Circulatory assistance by way of long-term cardiopulmonary bypass

From 1978 to 1986, 46 patients underwent prolonged circulatory support of 5-39 hours duration, at the Centre Chirurgical Marie Lannelongue. Indication for circulatory support was decided in the immediate postoperative stage, or later in patients with major, intractable heart failure, not responsive to standard resuscitative treatment. Patient details and equipment used are described, together with the details of monitoring. Outcome was favourable in 20 to 35% of cases, depending on the severity of the underlying cardiac pathology. Circulatory support by way of cardiopulmonary bypass (CPB) proved a readily feasible and reliable procedure. The method is an effective resuscitative technique, applicable in cases of reversible underlying pathology. In extreme cases, it may constitute an intermediate step before proceeding to cardiac transplantation or total circulatory support using a mechanical device such as an artificial heart.

Imaging findings in fetal diaphragmatic abnormalities

Imaging plays a key role in the detection of a diaphragmatic pathology in utero. US is the screening method, but MRI is increasingly performed. Congenital diaphragmatic hernia is by far the most often diagnosed diaphragmatic pathology, but unilateral or bilateral eventration or paralysis can also be identified. Extralobar pulmonary sequestration can be located in the diaphragm and, exceptionally, diaphragmatic tumors or secondary infiltration of the diaphragm from tumors originating from an adjacent organ have been observed in utero. Congenital abnormalities of the diaphragm impair normal lung development. Prenatal imaging provides a detailed anatomical evaluation of the fetus and allows volumetric lung measurements. The comparison of these data with those from normal fetuses at the same gestational age provides information about the severity of pulmonary hypoplasia and improves predictions about the fetus's outcome. This information can help doctors and families to make decisions about management during pregnancy and after birth. We describe a wide spectrum of congenital pathologies of the diaphragm and analyze their embryological basis. Moreover, we describe their prenatal imaging findings with emphasis on MR studies, discuss their differential diagnosis and evaluate the limits of imaging methods in predicting postnatal outcome.

Effects of Renal Replacement Therapy in Patients Receiving Extracorporeal Membrane Oxygenation: A Meta-Analysis

The use of renal replacement therapy (RRT) in patients receiving extracorporeal membrane oxygenation (ECMO) is increasing, but the effect of RRT on ECMO is controversial. We performed a meta-analysis to determine whether RRT is related to higher mortality in patients receiving ECMO. We searched MEDLINE, EMBASE, the Cochrane Library, and KoreaMed and found 43 observational studies with 21,624 patients receiving ECMO and then compared inpatient mortality rates of patients receiving ECMO both with and without RRT. The risk ratio (RR) of mortality between patients receiving RRT and those not receiving RRT tended to decrease as the mortality of the group not receiving RRT increased. Among patients with RRT use rates of 30% and higher, the overall mortality rates for all patients receiving ECMO tended to decrease. We found that the increase in the RR for RRT tended to be greater the longer the initiation of RRT was delayed. We suggest that in patients receiving ECMO who have high RRT use rates, RRT may decrease mortality rates.

Determinants of survival and resource utilization for pediatric extracorporeal membrane oxygenation in the United States 1997-2009

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) remains a vital therapy for children requiring cardiopulmonary support.

METHODS

The Kids' Inpatient Database (KID) was analyzed for ECMO (ICD-9-CM 39.65) patients between 1997 and 2009.

RESULTS

Overall, 8005 cases were identified, consisting of neonatal (ECMO <30days of life; 33%), infant (30days to 1year; 46%), young child (1year to 5years; 9.7%), and older child (>5years; 11%) groups. Patients were most commonly male (56%), Caucasian (49%), and insured by Medicaid (46%). ECMO was indicated for respiratory distress syndrome (RDS; 33%), cardiac and circulatory congenital anomalies (CCCA; 22%), congenital diaphragmatic hernia (CDH; 13%), and persistent pulmonary hypertension of the newborn (PPHN; 10%). On multivariate analysis, length of stay (LOS) decreased over the study period, while total charges (TC) increased over time, p<0.001. Survival was higher for boys and those treated in large or urban teaching hospitals, p<0.05. ECMO for CDH, CCCA, and RDS had the highest associated mortality, p<0.001. Neonatal and infant ECMO had no difference in mortality vs. older children.

CONCLUSIONS

While LOS for ECMO has decreased over time, TC has increased steadily. Improved survival is found in boys and patients at large or urban teaching hospitals. CDH, CCCA, and RDS portend poor survival outcomes as indicators for ECMO.

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).

ECMO in neonates: neuroimaging findings and outcome

Extracorporeal membrane oxygenation (ECMO) is a rescue therapy for newborns with severe but reversible respiratory failure. Although ECMO has significantly improved survival, it is associated with substantial complications, of which intracranial injuries are the most important. These injuries consist of hemorrhagic and non-hemorrhagic, ischemic lesions. Different from the classical presentation of hemorrhages in preterm infants, hemorrhages in ECMO-treated newborns are mainly parenchymal and with a high percentage in the posterior fossa area. There are conflicting data on the predominant occurrence of cerebral lesions in the right hemisphere. The existence of intracerebral injuries and the classification of its severity are the major predictors of neurodevelopmental outcome. This section will discuss the known data on intracranial injury in the ECMO population and the effect of ECMO on the brain.

Neurologic complications of cardiac surgery and interventional cardiology

A wide array of neurologic complications can occur in relation to cardiac surgical procedures, most of which are transient and do not result in permanent sequelae. Specific neurologic insults can occur depending on the type of cardiac procedure and are an important cause of morbidity and mortality. Neurologists practicing in the hospital setting as well as outpatient neurologists should be familiar with the cardiac surgical procedures currently available. Prompt identification of neurologic deficits is important in order to plan an appropriate systematic evaluation and initiate possible treatments in a timely manner. This chapter provides a comprehensive overview of all facets of neurologic complications after cardiac surgical procedures.

Moderately preterm, late preterm and early term infants: research needs

In spite of increased appreciation that all preterm infants and early term infants are at higher risk for mortality and morbidities compared with their term counterparts, there are many knowledge gaps affecting optimal clinical care for this vulnerable population. This article presents a research agenda focusing on the systems biology, epidemiology, and clinical and translational sciences on this topic.

Neurologic complications and neurodevelopmental outcome with extracorporeal life support

Extracorporeal life support is used to support patients of all ages with refractory cardiac and/or respiratory failure. Extracorporeal membrane oxygenation (ECMO) has been used to rescue patients whose predicted mortality would have otherwise been high. It is associated with acute central nervous system (CNS) complications and with long- term neurologic morbidity. Many patients treated with ECMO have acute neurologic complications, including seizures, hemorrhage, infarction, and brain death. Various pre-ECMO and ECMO factors have been found to be associated with neurologic injury, including acidosis, renal failure, cardiopulmonary resuscitation, and modality of ECMO used. The risk of neurologic complication appears to vary by age of the patient, with neonates appearing to have the highest risk of acute central nervous system complications. Acute CNS injuries are associated with increased risk of death in a patient who has received ECMO support. ECMO is increasingly used during cardiopulmonary resuscitation when return of spontaneous circulation is not achieved rapidly and outcomes may be good in select populations. Economic analyses have shown that neonatal and adult respiratory ECMO are cost effective. There have been several intriguing reports of active physical rehabilitation of patients during ECMO support that is well tolerated and may improve recovery. Although there is evidence that some patients supported with ECMO appear to have very good outcomes, there is limited understanding of the long-term impact of ECMO on quality of life and long-term cognitive and physical functioning for many groups, especially the cardiac and pediatric populations. This deserves further study.

Brain injury associated with neonatal extracorporeal membrane oxygenation in the Netherlands: a nationwide evaluation spanning two decades

OBJECTIVE

To determine the prevalence of and to classify ultrasound-proven brain injury during neonatal extracorporeal membrane oxygenation in The Netherlands.

DESIGN

Retrospective nationwide study (Rotterdam and Nijmegen), spanning two decades.

SETTING

Level III university hospitals.

SUBJECTS

All neonates who underwent neonatal extracorporeal membrane oxygenation from 1989 to 2010.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Cranial ultrasound images were reviewed independently by two investigators without knowledge of primary diagnosis, outcome, type of extracorporeal membrane oxygenation, or statistics. The scans were reviewed for lesion type and timing, with the use of a refined classification method for focal brain injury. Extracorporeal membrane oxygenation type was venoarterial in 88%. Brain abnormalities were detected in 17.3%: primary hemorrhage was most frequent (8.8%). Stroke was identified in 5% of the total group, with a notable significant preference for the left hemisphere (in 70%). Lobar hematoma (prevalence 2.2 %) was also significantly left predominant.

CONCLUSION

The incidence of brain injury found with cranial ultrasound in The Netherlands of the patients treated with extracorporeal membrane oxygenation during the neonatal period was 17.3%. Primary hemorrhage was the largest group of lesions, not clearly side-specific except for lobar bleeding, most probably related to changes in venous flow. Arterial ischemic stroke occurred predominant in the left hemisphere.