Seizures as a predictor of long-term neurodevelopmental outcome in survivors of neonatal extracorporeal membrane oxygenation (ECMO)

Brain development in newborns and infants after ECMO

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) not only significantly improves survival rates in severely ill neonates but also is associated with long-term neurodevelopmental issues. To systematically review the available literature on the neurodevelopmental outcomes of neonates and infants who have undergone ECMO treatment, with a focus on motor deficits, cognitive impairments, sensory impairments, and developmental delays. This review aims to understand the incidence, prevalence, and risk factors for these problems and to explore current nursing care and management strategies.

DATA SOURCES

A comprehensive literature search was performed across PubMed, EMBASE, and Web of Science using a wide array of keywords and phrases pertaining to ECMO, neonates, infants, and various facets of neurodevelopment. The initial screening involved reviewing titles and abstracts to exclude irrelevant articles, followed by a full-text assessment of potentially relevant literature. The quality of each study was evaluated based on its research methodology and statistical analysis. Moreover, citation searches were conducted to identify potentially overlooked studies. Although the focus was primarily on neonatal ECMO, studies involving children and adults were also included due to the limited availability of neonate-specific literature.

RESULTS

About 50% of neonates post-ECMO treatment exhibit varying degrees of brain injury, particularly in the frontal and temporoparietal white matter regions, often accompanied by neurological complications. Seizures occur in 18%-23% of neonates within the first 24 hours, and bleeding events occur in 27%-60% of ECMO procedures, with up to 33% potentially experiencing ischemic strokes. Although some studies suggest that ECMO may negatively impact hearing and visual development, other studies have found no significant differences; hence, the influence of ECMO remains unclear. In terms of cognitive, language, and intellectual development, ECMO treatment may be associated with potential developmental delays, including lower composite scores in cognitive and motor functions, as well as potential language and learning difficulties. These studies emphasize the importance of early detection and intervention of potential developmental issues in ECMO survivors, possibly necessitating the implementation of a multidisciplinary follow-up plan that includes regular neuromotor and psychological evaluations. Overall, further multicenter, large-sample, long-term follow-up studies are needed to determine the impact of ECMO on these developmental aspects.

CONCLUSIONS

The impact of ECMO on an infant's nervous system still requires further investigation with larger sample sizes for validation. Fine-tuned management, comprehensive nursing care, appropriate patient selection, proactive monitoring, nutritional support, and early rehabilitation may potentially contribute to improving the long-term outcomes for these infants.

Pediatric ECLS Neurologic Management and Outcomes

Neurologic complications associated with extracorporeal life support (ECLS), including seizures, ischemia/infarction, and intracranial hemorrhage significantly increase morbidity and mortality in pediatric and neonatal patients. Prompt recognition of adverse neurologic events may provide a window to intervene with neuroprotective measures. Many neuromonitoring modalities are available with varying benefits and limitations. Several pre-ECLS and ECLS-related factors have been associated with an increased risk for neurologic complications. These may be patient- or circuit-related and include modifiable and non-modifiable factors. ECLS survivors are at risk for long-term neurological sequelae affecting neurodevelopmental outcomes. Possible long-term outcomes range from normal development to severe impairment. Patients should undergo a neurological evaluation prior to discharge, and neurodevelopmental assessments should be included in each patient's structured, multidisciplinary follow-up. Safe pediatric and neonatal ECLS management requires a thorough understanding of neurological complications, neuromonitoring techniques and limitations, considerations to minimize risk, and an awareness of possible long-term ramifications. With a focus on ECLS for respiratory failure, this manuscript provides a review of these topics and summarizes best practice guidelines from international organizations and expert consensus.

Extracorporeal Membrane Oxygenation for Neonates With Congenital Diaphragmatic Hernia: Prevalence of Seizures and Outcomes

OBJECTIVES

We aimed to determine the prevalence of electrographic seizures and associated odds of adverse outcomes of electrographic seizures in neonates with congenital diaphragmatic hernia (CDH) receiving extracorporeal membrane oxygenation (ECMO).

DESIGN

Retrospective, descriptive case series.

SETTING

Neonatal ICU (NICU) in a quaternary care institution.

PATIENTS

All neonates with CDH receiving ECMO undergoing continuous electroencephalographic monitoring (CEEG) and follow-up between January 2012 and December 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

All eligible neonates with CDH receiving ECMO underwent CEEG (n = 75). Electrographic seizures occurred in 14 of 75 (19%): they were exclusively electrographic-only in nine of 14, both electrographic-only and electroclinical in three of 14, and electroclinical only in two of 14. Two neonates developed status epilepticus. We identified an association between presence of seizures, rather than not, and longer duration of initial session of CEEG monitoring (55.7 hr [48.2-87.3 hr] vs 48.0 hr [43.0-48.3 hr]; p = 0.001). We also found an association between presence of seizures, rather than not, and greater odds of use of a second CEEG monitoring (12/14 vs 21/61; odds ratio [OR], 11.43 [95% CI, 2.34-55.90; p = 0.0026). Most neonates with seizures (10/14), experienced their onset of seizures more than 96 hours after the start of ECMO. Overall, the presence of electrographic seizures, compared with not, was associated with lower odds of survival to NICU discharge (4/14 vs 49/61; OR 0.10 [95% CI 0.03 to 0.37], p = 0.0006). Also, the presence of seizures-rather than not-was associated with greater odds of a composite of death and all abnormal outcomes on follow-up (13/14 vs 26/61; OR, 17.5; 95% CI, 2.15-142.39; p = 0.0074).

CONCLUSIONS

Nearly one in five neonates with CDH receiving ECMO developed seizures during the ECMO course. Seizures were predominantly electrographic-only and when present were associated with great odds of adverse outcomes. The current study provides evidence to support standardized CEEG in this population.

Seizures in children undergoing extracorporeal membrane oxygenation: a systematic review and meta-analysis

OBJECTIVES

To investigate the incidence of seizures and short-term mortality associated with seizures in children undergoing extracorporeal membrane oxygenation (ECMO).

METHODS

PubMed, Embase, and Web of Science were searched from inception to September 2021. Study quality was assessed using the Newcastle-Ottawa Scale. Random effects meta-analysis was conducted.

RESULTS

Fourteen studies met the inclusion criteria for quantitative meta-analysis. The cumulative estimate of seizure incidence was 15% (95% CI: 12-17%). Studies using electroencephalography reported a higher incidence of seizures compared with those using electro-clinical criteria (19% vs. 9%, P = 0.034). Furthermore, 75% of seizures were subclinical. Children receiving extracorporeal cardiopulmonary resuscitation (ECPR) exhibited a higher incidence of seizures compared to children with respiratory and cardiac indications. Seizure incidence was higher in patients undergoing venoarterial (VA) ECMO compared with venovenous (VV) ECMO. The pooled odds ratio of mortality was 2.58 (95% CI: 2.25-2.95) in those developed seizures.

CONCLUSION

The incidence of seizures in children requiring ECMO was 15% and majority of seizures were subclinical. The incidence of seizures was higher in patients receiving ECPR than in those with respiratory and cardiac indications. Seizures were more frequent in patients undergoing VA ECMO than VV ECMO. Seizures were associated with increased short-term mortality.

IMPACT

The incidence of seizures in children undergoing extracorporeal membrane oxygenation (ECMO) was ~15% and majority of the seizures were subclinical. Seizures were associated with increased short-term mortality. Risk factors for seizures were extracorporeal cardiopulmonary resuscitation and venoarterial ECMO. Electroencephalography (EEG) monitoring is recommended in children undergoing ECMO and further studies on the optimal protocol for EEG monitoring are necessary.

Utility of cephalic drains in infants receiving extracorporeal membrane oxygenation

INTRODUCTION

The addition of cephalic drains (CDs) in extracorporeal membrane oxygenation (ECMO) to augment venous drainage may offer benefit, though their use is varied. Our objective was to describe our institution's experience with CDs including flow rates and patency. We also compared complication rates between patients with and without a CD.

METHODS

This retrospective cohort study included infants <12 months of age cannulated for ECMO between January 1, 2010 and September 30, 2019 at a single institution. Flow data were obtained for those with a CD. Demographic and complication rates were obtained for all.

RESULTS

Of 264 patients in the final cohort, 220 (83%) had a CD of which 93.2% remained patent to decannulation. CDs typically provided 30% or more of ECMO flow throughout the ECMO run. The median time to CD clot was 139 h (range 48-635 h). Patients with a clotted CD had longer ECMO runs than those whose CD remained patent (median 382 h [IQR 217-538] vs 139 h [IQR 91-246], p < 0.001). Survival to discharge was lower for those with clotted versus patent CD (14% vs 70%, p < 0.001). Mechanical complications were more common in patients with CD (p = 0.005). Seizures were more common in those without a CD (p = 0.021).

CONCLUSIONS

In this cohort, the majority of CDs placed remained patent at decannulation and provided substantial additional venous drainage. Mechanical problems were common in patients with CDs, but without clinical sequelae. Further study is warranted to elucidate CD impact on short- and long-term outcomes.

Neonatal respiratory and cardiac ECMO in Europe

Neonatal extracorporeal membrane oxygenation (ECMO) is a life-saving procedure for critically ill neonates suffering from a potentially reversible disease, causing severe cardiac and/or respiratory failure and refractory to maximal conventional management. Since the 1970s, technology, management, and clinical applications of neonatal ECMO have changed. Pulmonary diseases still represent the principal neonatal diagnosis, with an overall 74% survival rate, and up to one-third of cases are due to congenital diaphragmatic hernia. The overall survival rate in cardiac ECMO is lower, with congenital heart defect representing the main indication. This review provides an overview of the available evidence in the field of neonatal ECMO. We will address the changing epidemiology, basic principles, technologic advances in circuitry, and monitoring, and deliver a current multidisciplinary management framework, focusing on ECMO applications, complications, and long-term morbidities. Lastly, areas for further research will be highlighted.Conclusions: ECMO is a life support with a potential impact on long-term patients' outcomes. In the next years, advances in knowledge, technology, and expertise may push neonatal ECMO boundaries towards more premature and increasingly complex infants, with the final aim to reduce the burden of ECMO-related complications and improve overall patients' outcomes. What is Known: • ECMO is a life-saving option in newborns with refractory respiratory and/or cardiac failure. • The multidisciplinary ECMO management is challenging and may expose neonates to complications with an impact on long-term outcomes. What is New: • Advances in technology and biomaterials will improve neonatal ECMO management and, eventually, the long-term outcome of these complex patients. • Experimental models of artificial placenta and womb technology are under investigation and may provide clinical translation and future research opportunities.

Seizures Are Associated With Brain Injury in Infants Undergoing Extracorporeal Membrane Oxygenation

OBJECTIVE

Determine seizure frequency and association with neurologic outcomes in infants undergoing extracorporeal membrane oxygenation. Identify patient or clinical factors associated with seizures or brain injury on imaging.

METHODS

Retrospective, single-center study including infants less than 1 year of age, who underwent extracorporeal membrane oxygenation between 2012 and 2017.

RESULTS

A total of 104 infants met study criteria including 45 patients with continuous electroencephalographic (EEG) monitoring during their extracorporeal membrane oxygenation run and 59 infants without EEG. Seizures (electrographic-only or electro-clinical) were identified in 18 of the 45 (40%). Among the 18 infants with seizures, 14 (78%) had moderate to severe brain injury, whereas only 44% of those without seizures (12 of 27) on EEG had moderate to severe brain injury (P = .03). Cardiopulmonary resuscitation prior to extracorporeal membrane oxygenation (ECPR), mode of extracorporeal membrane oxygenation, length of stay, survival to discharge, and congenital heart disease were not associated with seizures. One of 10 patients with cyanotic congenital heart disease due to hypoplastic left heart syndrome had seizures compared with 7 of 10 patients with non-hypoplastic left heart syndrome lesions (P = .02). Seizures were associated with moderate to severe brain injury, after adjusting for ECPR and congenital heart disease (P = .04).

CONCLUSIONS

Electrographic seizures were common in patients undergoing extracorporeal membrane oxygenation and higher than previously reported. Seizures were associated with moderate to severe abnormalities on imaging, after adjusting for ECPR and congenital heart disease. This study adds to recent literature describing the risk of seizures in patients on extracorporeal membrane oxygenation and highlights the presence of brain injuries that may be identified by routine EEG surveillance.

Neurological Monitoring and Complications of Pediatric Extracorporeal Membrane Oxygenation Support

Extracorporeal membrane oxygenation is extracorporeal life support for life-threatening cardiopulmonary failure. Since its introduction, the use of extracorporeal membrane oxygenation has expanded to patients with more complex comorbidities without change in patient mortality rates. Although many patients survive, significant neurological complications like seizures, ischemic strokes, and intracranial hemorrhage can occur during extracorporeal membrane oxygenation care. The risks of these complications often add to the complexity of decision-making surrounding extracorporeal membrane oxygenation support. In this review, we discuss the pathophysiology and incidence of neurological complications in children supported on extracorporeal membrane oxygenation, factors influencing the incidence of these complications, commonly used neurological monitoring modalities, and outcomes for this complex patient population. We discuss the current literature on the use of electroencephalography for both seizure detection and monitoring of background electroencephalographic changes, in addition to the use of less commonly used imaging modalities like transcranial Doppler. We summarize the knowledge gaps and the lack of clinical consensus guidelines for managing these potentially life-changing neurological complications. Finally, we discuss future work to further understand the pathophysiology of extracorporeal membrane oxygenation-related neurological complications.

Electrographic Seizures and Brain Injury in Children Requiring Extracorporeal Membrane Oxygenation

BACKGROUND

Single-center studies suggest that up to 30% of children undergoing extracorporeal membrane oxygenation have electrographic seizures. The aim of this study was to characterize seizure prevalence, seizure risk factors, and brain injury prevalence in the pediatric extracorporeal membrane oxygenation population at a tertiary care children's hospital.

METHODS

We performed a retrospective systematic review of medical records for 86 consecutive children (neonates to age 21 years) who received Neurology consults and continuous video electroencephalography while undergoing extracorporeal membrane oxygenation from November 2015 to September 2018.

RESULTS

Continuous video electroencephalography was initiated in 86 of 170 children who required extracorporeal membrane oxygenation (51%); median duration of continuous vodeo electroencephalography was four days. Nineteen of 86 had electroencephalography-confirmed seizures (22%). Sixteen of 19 had seizures within the first 48 hours on continuous video electroencephalography. Interictal epileptiform discharges were a significant risk factor for seizures; 89% of those with seizures versus 46% of those without had interictal epileptiform discharges (P < 0.001, Fisher's exact test). Children with seizures also had higher pericannulation lactate (median 6.7, interquartile range of 4.3 to 19.0 for those with, and median 4.0, interquartile range of 2.0 to 7.3 for those without; P = 0.02, Mann-Whitney U test). Seizures were associated with hemorrhage on neuroimaging (68% of children with seizures had intracranial hemorrhage versus 34% of those without, P = 0.01, chi-square test).

CONCLUSION

Approximately half the children undergoing extracorporeal membrane oxygenation received continuous video electroencephalography during the study period, and 22% had seizures. Interictal epileptiform discharges and elevated pre-extracorporeal membrane oxygenation lactate levels were risk factors for seizures; seizures were associated with intracranial hemorrhage.

Neurologic Outcomes in a Two-Center Cohort of Neonatal and Pediatric Patients Supported on Extracorporeal Membrane Oxygenation

Contemporary studies of long-term outcomes in children supported on extracorporeal membrane oxygenation (ECMO) in the United States are limited. We enrolled 99 ECMO patients between July 2010 and June 2015 in a two-center prospective observational study that included neurologic and neuropsychologic evaluation at 6 and 12 months, using standardized outcome measures. Pre-ECMO, 20 (20%) had a pre-existing neurologic diagnosis, 40 (40%) had cardiac arrest, and 10 of 47 (21%) children with neuroimaging had acute abnormal findings. Of 50 children eligible for follow-up at 6 or 12 months, 40 (80%) returned for at least one visit. At the follow-up visit of longest interval from ECMO, the median Vineland Adaptive Behavior Scales-II (VABS-II) score was 91 (interquartile range [IQR], 81-98), the median Pediatric Stroke Outcome Measure (PSOM) score was 1 (IQR, 0-2), and the median Mullen Scales of Early Learning composite score was 85 (IQR, 72-96). Presence of new neuroimaging abnormalities during ECMO or within 6 weeks post-ECMO was associated with VABS-II score <85 or death within 12 months after ECMO. The Pediatric Cerebral Performance Category at hospital discharge showed a strong relationship with unfavorable VABS-II and PSOM scores at 6 or 12 months after ECMO. In this study, we report a higher prevalence of pre-ECMO neurologic conditions than previously described. In survivors to hospital discharge, median scores for adaptive behavior and cognitive, neurologic, and quality of life assessments were all below the general population means, but most deficits would be considered minor within each of the domains tested.

Prevalence of Seizures in Pediatric Extracorporeal Membrane Oxygenation Patients as Measured by Continuous Electroencephalography

OBJECTIVES

Standards for neuromonitoring during extracorporeal membrane oxygenation support do not currently exist, and there is wide variability in practice. We present our institutional experience at an academic children's hospital since establishment of a continuous electroencephalography monitoring protocol for extracorporeal membrane oxygenation patients.

DESIGN

Retrospective, single-center study.

SETTING

Neonatal ICU and PICU in an urban, quaternary care center.

PATIENTS

All neonatal and pediatric patients requiring extracorporeal membrane oxygenation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

During the study period, 70 patients were cannulated for extracorporeal membrane oxygenation and had continuous electroencephalography monitoring for greater than 24 hours. Electroencephalographic seizures were observed in 16 of 70 patients (23%), including five patients (7%) who were in status epilepticus. Among patients with continuous electroencephalography seizures, nine (56%) had subclinical nonconvulsive status epilepticus and eight (50%) had seizures in the initial 24 hours of extracorporeal membrane oxygenation support. Survival to hospital discharge was significantly greater for extracorporeal membrane oxygenation patients without seizures (74% vs 44%; p = 0.02).

CONCLUSIONS

Seizures occur in a significant proportion of pediatric and neonatal extracorporeal membrane oxygenation patients, frequently in the initial 24 hours after extracorporeal membrane oxygenation cannulation. Because seizures are associated with significantly decreased survival, neuromonitoring early in the extracorporeal membrane oxygenation course is important and useful. Further studies are needed to correlate electroencephalography findings with neurologic outcome.

Neurologic Outcomes After Extracorporeal Membrane Oxygenation: A Systematic Review

OBJECTIVES

The goal of this systematic review of the literature was to summarize neurologic outcomes following neonatal and pediatric extracorporeal membrane oxygenation.

DATA SOURCES

We conducted electronic searches of PubMed, Scopus, Web of Science, CINAHL, Cochrane, and EMBASE.

STUDY SELECTION

Inclusion criteria included publication dates 2000-2016, patient ages 0-18 years, and use of standardized measures to evaluate outcomes after extracorporeal membrane oxygenation.

DATA EXTRACTION

We identified 3,497 unique citations; 60 full-text articles were included in the final review.

DATA SYNTHESIS

Studies evaluated patients with congenital diaphragmatic hernia (7), cardiac disease (8), cardiac arrest (13), and mixed populations (32). Follow-up was conducted at hospital discharge in 10 studies (17%) and at a median of 26 months (interquartile range, 8-61 mo) after extracorporeal membrane oxygenation in 50 studies (83%). We found 55 outcome measures that assessed overall health and function (4), global cognitive ability (7), development (4), motor function (5), adaptive function (2), behavior/mood (6), hearing (2), quality of life (2), school achievement (5), speech and language (6), learning and memory (4), and attention and executive function (8). Overall, 10% to as many as 50% of children scored more than 2 SDS below the population mean on cognitive testing. Behavior problems were identified in 16-46% of children tested, and severe motor impairment was reported in 12% of children. Quality of life of former extracorporeal membrane oxygenation patients evaluated at school age or adolescence ranged from similar to healthy peers, to 31-53% having scores more than 1 SD below the population mean.

CONCLUSIONS

This systematic review of the literature suggests that children who have undergone extracorporeal membrane oxygenation suffer from a wide range of disabilities. A meta-analysis was not feasible due to heterogeneity in pathologies, outcome measures, and age at follow-up, underscoring the importance of developing and employing a core set of outcomes measures in future extracorporeal membrane oxygenation studies.

An overview of medical ECMO for neonates

Extracorporeal membrane oxygenation (ECMO), a life-saving therapy for respiratory and cardiac failure, was first used in neonates in the 1970s. The indications and criteria for ECMO have changed over the years, but it continues to be an important option for those who have failed other medical therapies. Since the Extracorporeal Life Support Organization (ELSO) Registry was established in 1989, more than 29,900 neonates have been placed on ECMO for respiratory failure, with 84% surviving their ECMO course, and 73% surviving to discharge or transfer. In this chapter, we will review the basics of ECMO, patient characteristics and criteria, patient management, ECMO complications, special uses of neonatal ECMO, and patient outcomes.

Patterns of Head Computed Tomography Abnormalities During Pediatric Extracorporeal Membrane Oxygenation and Association With Outcomes

BACKGROUND

We sought to classify type and distribution of acute infarction and hemorrhage on head computed tomography (CT) during pediatric extracorporeal membrane oxygenation (ECMO). We also analyzed the occurrence of seizures on electroencephalography and outcomes between those with and without CT abnormalities.

METHODS

We conducted a single center observational study in pediatric intensive care units. The medical records of 179 children who underwent ECMO between 2009 and 2013 were reviewed. No interventions were done.

RESULTS

A total of 46% (82/179) of children underwent CT. Of these, 60% (49/82) had acute pathology. Cerebral infarction occurred in 55% (27/49) and hemorrhage in 41% (20/49). Infarction was arterial in 67% (18/27) with a preponderance in the middle cerebral artery territory (17 patients). Infarction was bilateral in 41% (11/27) and not specific to the side of cannulation in the rest. Sensitivity and specificity for head ultrasound in predicting infarction on CT were 100% and 53%, respectively. A total of 36% (65/179) underwent continuous encephalography monitoring; 22% (14/65) of these had electrographic seizures. Electrographic seizures were increased in those with infarction (odds ratio [OR], 6.81; 95% confidence interval [CI], 1.98 to 23.43). Survival was reduced with both infarction (OR, 0.22; 95% CI, 0.09 to 0.54) and hemorrhage (OR, 0.31; 95% CI, 0.13 to 0.72). Children with CT abnormalities had more unfavorable outcomes (P = 0.01).

CONCLUSIONS

Head ultrasound is insufficient to rule out infarction. Infarction is middle cerebral artery predominant and associated with an increased risk of electrographic seizures.

Electrographic Seizures in Children and Neonates Undergoing Extracorporeal Membrane Oxygenation

OBJECTIVE

We aimed to determine the prevalence and risk factors for electrographic seizures in neonates and children requiring extracorporeal membrane oxygenation support.

DESIGN

Prospective quality improvement project.

SETTING

Quaternary care pediatric institution.

PATIENTS

Consistent with American Clinical Neurophysiology Society electroencephalographic monitoring recommendations, neonates and children requiring extracorporeal membrane oxygenation support underwent clinically indicated electroencephalographic monitoring.

INTERVENTIONS

We performed a 2-year quality improvement study from July 2013 to June 2015 evaluating electrographic seizure prevalence and risk factors.

MAIN RESULTS

Ninety-nine of 112 patients (88%) requiring extracorporeal membrane oxygenation support underwent electroencephalographic monitoring. Electrographic seizures occurred in 18 patients (18%), of whom 11 patients (61%) had electrographic status epilepticus and 15 patients (83%) had exclusively electrographic-only seizures. Electrographic seizures were more common in patients with low cardiac output syndrome (p = 0.03). Patients with electrographic seizures were more likely to die prior to discharge (72% vs 30%; p = 0.01) and have unfavorable outcomes (54% vs 17%; p = 0.004) than those without electrographic seizures.

CONCLUSIONS

Electrographic seizures occurred in 18% of neonates and children requiring extracorporeal membrane oxygenation support, often constituted electrographic status epilepticus, and were often electrographic-only thereby requiring electroencephalographic monitoring for identification. Low cardiac output syndrome was associated with an increased risk for electrographic seizures. Electrographic seizures were associated with higher mortality and unfavorable outcomes. Further investigation is needed to determine whether electrographic seizures identification and management improves outcomes.

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.

Extracorporeal membrane oxygenation for neonatal and pediatric respiratory failure: an evidence-based review of the past decade (2002-2012)

OBJECTIVE

To provide a comprehensive evidence-based review of extracorporeal membrane oxygenation for neonatal and pediatric respiratory failure.

DATA SOURCE

A thorough computerized bibliographic search of the clinical literature regarding the use of extracorporeal membrane oxygenation in the neonatal and pediatric populations.

STUDY SELECTION

Clinical trials published between January 1, 2002, and October 1, 2012, including "extracorporeal membrane oxygenation" or "ECMO" and limited to studies involving humans aged 0-18 years. Trials focused on extracorporeal membrane oxygenation for cardiac indications were excluded from this study, unless the study was evaluating ancillary therapies in conjunction with extracorporeal membrane oxygenation.

DATA EXTRACTION

Studies were evaluated for inclusion based on reporting of patient outcomes and/or strategic considerations, such as cannulation strategies, timing of extracorporeal membrane oxygenation utilization, and ancillary therapies.

DATA SYNTHESIS

Pertinent data are summarized, and the available data are objectively classified based on the value of the study design from which the data are obtained.

CONCLUSIONS

Despite a large number of published extracorporeal membrane oxygenation studies, there remains a paucity of high-quality clinical trials. The available data support continued use of extracorporeal membrane oxygenation for respiratory failure refractory to conventional therapy for neonatal and pediatric patients without significant comorbidities. Further research is needed to better quantify the benefit of extracorporeal membrane oxygenation and the utility of many therapies commonly applied to extracorporeal membrane oxygenation patients.

A review of long-term EEG monitoring in critically ill children with hypoxic-ischemic encephalopathy, congenital heart disease, ECMO, and stroke

Continuous EEG monitoring is being used with increasing frequency in critically ill children with hypoxic ischemic encephalopathy, congenital heart disease, stroke, and extracorporeal membrane oxygenation (ECMO). The primary indication for EEG monitoring is to identify electrographic seizures and electrographic status epilepticus, which have been associated with worse outcome in some populations. A secondary indication is to provide prognostic information. This review summarizes the available data regarding continuous EEG monitoring in critically ill children with special attention to hypoxic ischemic encephalopathy, congenital heart disease, stroke, and children undergoing ECMO.

Nonconvulsive seizures are common in children treated with extracorporeal cardiac life support

OBJECTIVES

The prevalence of electrographic seizures or nonconvulsive status epilepticus and the effect of such seizures in children treated with extracorporeal cardiac life support are not known. We investigated the occurrence of electrographic abnormalities, including asymmetries in amplitude or frequency of the background rhythm and interictal activity in children undergoing extracorporeal cardiac life support and their association with seizures. We compared mortality and radiologic evidence of neurologic injury between patients with seizures and those without seizures.

DESIGN

Retrospective review of medical records and the Extracorporeal Life Support Organization database.

SETTING

PICU at a single institution.

PATIENTS

All pediatric patients up to 18 years old, who had extracorporeal cardiac life support and continuous electroencephalography monitoring between the years 2006 and 2011.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Nineteen patients treated with extracorporeal cardiac life support underwent continuous electroencephalography monitoring. Seizures occurred in four patients (21%) and were exclusively nonconvulsive in three patients. Two of these four patients had nonconvulsive status epilepticus. Interictal discharges on electroencephalography were associated with seizures (odds ratio, 19.5 [95% CI, 1.29-292.75]; p = 0.03). Only 50% of the seizures were detected in the first hour of monitoring, whereas all seizures were detected within 24 hours. All patients with seizures had structural abnormalities seen on neuroimaging. Seizures were not significantly associated with increased mortality. To evaluate for ascertainment bias, we compared outcomes between patients who underwent extracorporeal cardiac life support and received continuous electroencephalography monitoring and those patients who underwent extracorporeal cardiac life support during the study period but did not receive electroencephalography (n = 30).

CONCLUSIONS

Seizures are common in children during extracorporeal cardiac life support, and most seizures are nonconvulsive. In patients undergoing extracorporeal cardiac life support, clinical features are unreliable indicators of the presence of seizures. The presence of seizures is suggestive of CNS injury. This study is limited by the exclusion of neonates, a feature of the clinical use of electroencephalography at our institution. Although seizures were not associated with increased mortality, further prospective studies in larger populations are needed to assess the long-term morbidity associated with seizures during extracorporeal cardiac life support.

Neurological complications of extracorporeal membrane oxygenation in children

OBJECT

Extracorporeal membrane oxygenation (ECMO) is a potentially life-saving treatment for patients in refractory cardiorespiratory failure. Neurological complications that result from ECMO treatment are known to significantly impact patient survival and quality of life. The purpose of this study was to review the incidence of neurological complications of ECMO in the pediatric population and the role of neurosurgery in the treatment of these patients.

METHODS

Data were obtained from the national Extracorporeal Life Support Organization (ELSO) Registry for the years 1990 to 2009. The neurological complications recorded by the registry include CNS hemorrhage, CNS infarction, and seizure. The ECMO Registry at the authors' institution was then searched, and 3 pediatric patients who had undergone craniotomy during ECMO treatment were identified.

RESULTS

Children in the ELSO Registry who were treated with ECMO survived to hospital discharge in 65% of cases. Intracranial hemorrhage occurred in 7.4% of the ECMO-treated patients, with 36% of those surviving to hospital discharge. Hemorrhage was more likely in patients younger than 30 days old and in those requiring ECMO for cardiac indications. Cerebral infarction occurred in 5.7% of all ECMO-treated patients. Clinically diagnosed seizures occurred in 8.4% of all ECMO-treated patients. The ECMO Registry at the authors' institution revealed that 1898 patients were treated there. Intracranial hemorrhage was diagnosed in 81 patients (5.8%), and 3 of these patients were treated with craniotomy. Two of the patients were alive with minimal neurological impairment and normal school performance at 10 and 16 years of follow-up.

CONCLUSIONS

Intracranial hemorrhage is a serious complication of ECMO treatment. While the surgical risk is substantial, there may be a role for surgical evacuation of hemorrhage in well-selected patients.

Neurologic outcome at school entry for newborns treated with extracorporeal membrane oxygenation for noncardiac indications

The neurologic outcomes at school age in children who underwent neonatal extracorporeal membrane oxygenation for noncardiac indications in a single institution surviving till the age of 5 years was determined by standardized neurologic assessment. Of 42 newborns undergoing extracorporeal membrane oxygenation, 24 underwent neurologic assessment by a single neurologist at 5 years of age. In all, 12 (50%) had a normal neurologic outcome. Lower gestational age and birth weight was found to be associated with an abnormal outcome as was septic shock as an indication for extracorporeal membrane oxygenation initiation. The number of peri-extracorporeal membrane oxygenation complications experienced by a child was associated with later epilepsy. Although invasive and implemented in critically ill infants, half of newborns undergoing extracorporeal membrane oxygenation will have a normal neurologic outcome at school age. Preexisting factors, rather than factors related to the extracorporeal membrane oxygenation itself, appear to be greater determinants of later neurologic outcomes.

Survie et devenir clinique des nouveau-nés mis en assistance respiratoire extracorporelle

OBJECTIVES

To assess the prognosis of newborn infants with refractory hypoxemia who required extracorporeal membrane oxygenation (ECMO).

METHODS

Eighty-nine newborn infants treated by ECMO during more than 24 hours over a 8-year period (1996-2003) were included in this observational cohort study with a 9-month and 24-month evaluation.

RESULTS

Respiratory failure mainly resulted from meconium aspiration syndrome (MAS, 43%), congenital diaphragmatic hernia (CDH, 15%) and sepsis (15%). Overall survival at hospital discharge was 67%. Infants with MAS had the best survival rate (82%) and those with CDH had the worst (46%). Of the remaining 60 survivors, 53% remained oxygen dependent at 28 days and 33% at 45 days. At the age of 2 years, only 1 infant remained oxygen dependent (but did not required oxygen at 3 years) and only 3 infants had significant neurodevelopmental problems. CDH group was associated with a prolonged duration in supplementary oxygen (P<0.001) and a prolonged duration for tube feeding (P=0.01) as compared with other diagnoses. Regarding neurologic outcome, CDH infants had the poorer neurological acquisition rate at 9 months but a very good evolution by the time of the 24-month evaluation.

CONCLUSIONS

Morbidity in ECMO survivors is low considering the severity of illness in the newborn period, mainly related to pulmonary and feeding dysfunctions during the first months, in particular for the CDH group. Outcome at the age of 2 years of CDH infants is most often favourable regarding growth and neurodevelopmental evolution.