Esperanza: The First Neonatal ECMO Patient

Prevalence and Neurological Outcomes of Comatose Patients With Extracorporeal Membrane Oxygenation

OBJECTIVES

To investigate prevalence, risk factors, and in-hospital outcomes of comatose extracorporeal membrane oxygenation (ECMO) patients.

DESIGN

Retrospective observational.

SETTING

Tertiary academic hospital.

PARTICIPANTS

Adults received venoarterial (VA) or venovenous (VV) ECMO support between November 2017 and April 022.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We defined 24-hour off sedation as no sedative infusion (except dexmedetomidine) or paralytics administration over a continuous 24-hour period while on ECMO. Off-sedation coma (comaoff) was defined as a Glasgow Coma Scale score of ≤8 after achieving 24-hour off sedation. On-sedation coma (comaon) was defined as a Glasgow Coma Scale score of ≤8 during the entire ECMO course without off sedation for 24 hours. Neurological outcomes were assessed at discharge using the modified Rankin scale (good, 0-3; poor, 4-6). We included 230 patients (VA-ECMO 143, 65% male); 24-hour off sedation was achieved in 32.2% VA-ECMO and 26.4% VV-ECMO patients. Among all patients off sedation for 24 hours (n = 69), 56.5% VA-ECMO and 52.2% VV-ECMO patients experienced comaoff. Among those unable to be sedation free for 24 hours (n = 161), 50.5% VA-ECMO and 17.2% VV-ECMO had comaon. Comaoff was associated with poor outcomes (p < 0.05) in VA-ECMO and VV-ECMO groups, whereas comaon only impacted the VA-ECMO group outcomes. In a multivariable analysis, requirement of renal replacement therapy was an independent risk factor for comaoff after adjusting for ECMO configuration, after adjusting for ECMO configuration, acute brain injury, pre-ECMO partial pressure of oxygen in arterial blood, partial pressure of carbon dioxide in arterial blood, pH, and bicarbonate level (worst value within 24 hours before cannulation).

CONCLUSIONS

Comaoff was common and associated with poor outcomes at discharge. Requirement of renal replacement therapy was an independent risk factor.

[Peripheral extracorporeal membrane oxygenation in perioperative medicine : Principles, indications and challenges]

In recent years the number of patients treated in intensive care units by extracorporeal membrane oxygenation (ECMO) due to severe respiratory failure or cardiogenic shock has steadily increased [1]. Consequently, the number of invasive procedures and operations in these patients has also increased. A fundamental understanding of these systems and the clinical indications is therefore helpful for the practicing (non-cardiac) surgeon. This review article focuses on peripheral ECMO procedures: venovenous (V-V) ECMO for patients with respiratory failure and venoarterial (V-A) ECMO for circulatory support in cardiogenic shock.

Hybrid extracorporeal membrane oxynegation in pediatric intensive care patients: A single center experience: More is better?

BACKGROUND

The initial extracorporeal membrane oxygenation (ECMO) configuration is inefficient for patient oxygenation and flow, but by adding a Y-connector, a third or fourth cannula can be used to support the system, which is called hybrid ECMO.

METHODS

This was a single-center retrospective study consisting of patients receiving hybrid and standard ECMO in our PICU between January 2014 and January 2022.

RESULTS

The median age of the 12 patients who received hybrid ECMO and were followed up with hybrid ECMO was 140 (range, 82-213) months. The total median ECMO duration of the patients who received hybrid ECMO was 23 (8-72) days, and the median follow-up time on hybrid ECMO was 18 (range, 3-46) days. The mean duration of follow-up in the PICU was 34 (range, 14-184) days. PICU length of stay was found to be statistically significant and was found to be longer in the hybrid ECMO group (p = 0.01). Eight (67%) patients died during follow-up with ECMO. Twenty-eight-day mortality was found to be statistically significant and was found to be higher in the standard ECMO group (p = 0.03). The hybrid ECMO mortality rate was 66% (decannulation from ECMO). The hybrid ECMO hospital mortality rate was 75%. The standard ECMO mortality rate was 52% (decannulation from ECMO). The standard ECMO hospital mortality rate was 65%.

CONCLUSIONS

Even though hybrid ECMO use is rare, with increasing experience and new methods, more successful experience will be gained. Switching to hybrid ECMO from standard ECMO at the right time with the right technique can increase treatment success and survival.

The Story of ECMO

Extracorporeal Circulation in Neonatal Respiratory Failure: A Prospective Randomized Study. By RH Bartlett, DW Roloff, RG Cornell, AF Andrews, PW Dillon, JB Zwischenberger. Pediatrics 1985; 76:479-87. Extracorporeal membrane oxygenation (ECMO) is the use of mechanical devices to replace cardiac and pulmonary function in critical care. In the 1960s, laboratory research showed that extracorporeal circulation could be maintained for days using a membrane oxygenator. In the 1970s, the first clinical trials showed that ECMO could sustain life in severe cardiac and pulmonary failure for days or weeks, leading to organ recovery. From 1980 to 2000, ECMO became standard practice for neonatal and pediatric respiratory and cardiac failure. The critical clinical trial was a prospective randomized trial of ECMO in newborn respiratory failure, published in 1985. This is the classic article reviewed in this publication. This was the first use of a randomized, adaptive design trial to minimize the potential ethical dilemma inherent to clinical trials in which the endpoint is death. Other randomized trials followed, and ECMO is now standard practice for severe respiratory and cardiac failure in all age groups.

Veno-arterial extracorporeal membrane oxygenation for respiratory and cardiac support in neonates: a single center experience

Objective

Extracorporeal membrane oxygenation (ECMO) is an advanced life support that has been utilized in the neonate for refractory respiratory and circulatory failure. Striving for the best outcomes and understanding optimal surgical techniques continue to be at the forefront of discussion and research. This study presents a single-center experience of cervically cannulated neonatal patients on V-A ECMO, a description of our cannulation/decannulation techniques and our patient outcomes.

Methods

Single center retrospective review of neonates who received neck V-A ECMO support from January 2012 to December 2022. The data and outcomes of the patients were retrospectively analyzed.

Results

A total of 78 neonates received V-A ECMO support. There were 66 patients that received ECMO for respiratory support, the other 12 patients that received ECMO for cardiac support. The median duration of ECMO support was 109 (32-293) hours for all patients. During ECMO support, 20 patients died and 5 patients discontinued treatment due to poor outcome or the cost. A total of 53 (68%) patients were successfully weaned from ECMO, but 3 of them died in the subsequent treatment. Overall 50 (64%) patients survived to hospital discharge. In this study, 48 patients were cannulated using the vessel sparing technique, the other 30 patients were cannulated using the ligation technique. We found no significant difference in the rates of normal cranial MRI at discharge between survivors with and without common carotid artery ligation.

Conclusion

We achieved satisfactory outcomes of neonatal ECMO in 11-year experience. This study found no significant difference in early neuroimaging between survivors with and without common carotid artery ligation. The long-term neurological function of ECMO survivors warranted further follow-up and study.

Transfusion in Neonatal Extracorporeal Membrane Oxygenation: A Best Practice Review

Extracorporeal Membrane Oxygenation (ECMO) is an important tool for managing critically ill neonates. Bleeding and thrombotic complications are common and significant. An understanding of ECMO physiology, its interactions with the unique neonatal hemostatic pathways, and appreciation for the distinctive risks and benefits of neonatal transfusion as it applies to ECMO are required. Currently, there is variability regarding transfusion practices, related to changing norms and a lack of high-quality literature and trials. This review provides an analysis of the neonatal ECMO transfusion literature and summarizes available best practice guidelines.

Extracorporeal membrane oxygenation in paediatric cardiac surgery: 5-year single centre experience

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has become an integral part of paediatric cardiac surgery. We report the experience of a well-established ECMO service over 5 years.

METHODS

This retrospective study analysed all paediatric patients who required ECMO support following cardiac surgery from April 2015 to March 2020. Inclusion criteria were age less than 18 years and post-operative ECMO support. Patients were analysed dividing into groups according to the urgency for ECMO support (extracorporeal cardiopulmonary resuscitation (ECPR) and cardiac ECMO) and according to age (neonatal and paediatric ECMO groups). They were followed for 30-day, 6-month mortality, long-term survival, postoperative morbidity and the need for reintervention.

RESULTS

Forty-six patients were included who had a total of venoarterial (VA) 8 ECMO runs. The 5-year incidence of the need for VA ECMO after cardiac surgery was 3.3% (48 of the overall 1441 cases recorded). The median follow-up period was 3.5 (interquartile ranges, 0.8-4.7) years. Thirty-day, 6-month and follow-up survival rate was 85%, 65% and 52% respectively. At the 6-month follow-up, the ECPR group showed a trend towards worse survival compared with the cardiac ECMO group (47% vs. 55%) but with no statistical significance (p = 0.35). Furthermore, the survival rates between paediatric (60%) and neonatal (46%) ECMO groups were similar, with no statistical significance (p = 0.45). The rate of acute neurological events was 27% (13/48).

CONCLUSION

ECPR and neonatal ECMO groups had higher mortality. VA ECMO 30-day and 6-month survival rates were 85% and 65% respectively. Major neurological injury resulting in ECMO termination occurred in 3 patients. Accumulated experiences and protocols in ECMO management can improve mortality and morbidity.

On-Support and Postweaning Mortality in Postcardiotomy Extracorporeal Membrane Oxygenation

BACKGROUND

Postcardiotomy venoarterial extracorporeal membrane oxygenation (VA ECMO) is characterized by discrepancies between weaning and survival-to-discharge rates. This study analyzes the differences between postcardiotomy VA ECMO patients who survived, died on ECMO, or died after ECMO weaning. Causes of death and variables associated with mortality at different time points are investigated.

METHODS

The retrospective, multicenter, observational Postcardiotomy Extracorporeal Life Support Study (PELS) includes adults requiring postcardiotomy VA ECMO between 2000 and 2020. Variables associated with on-ECMO mortality and postweaning mortality were modeled using mixed Cox proportional hazards, including random effects for center and year.

RESULTS

In 2058 patients (men, 59%; median age, 65 years; interquartile range [IQR], 55-72 years), weaning rate was 62.7%, and survival to discharge was 39.6%. Patients who died (n = 1244) included 754 on-ECMO deaths (36.6%; median support time, 79 hours; IQR, 24-192 hours), and 476 postweaning deaths (23.1%; median support time, 146 hours; IQR, 96-235.5 hours). Multiorgan (n = 431 of 1158 [37.2%]) and persistent heart failure (n = 423 of 1158 [36.5%]) were the main causes of death, followed by bleeding (n = 56 of 754 [7.4%]) for on-ECMO mortality and sepsis (n = 61 of 401 [15.4%]) for postweaning mortality. On-ECMO death was associated with emergency surgery, preoperative cardiac arrest, cardiogenic shock, right ventricular failure, cardiopulmonary bypass time, and ECMO implantation timing. Diabetes, postoperative bleeding, cardiac arrest, bowel ischemia, acute kidney injury, and septic shock were associated with postweaning mortality.

CONCLUSIONS

A discrepancy exists between weaning and discharge rate in postcardiotomy ECMO. Deaths occurred during ECMO support in 36.6% of patients, mostly associated with unstable preoperative hemodynamics. Another 23.1% of patients died after weaning in association with severe complications. This underscores the importance of postweaning care for postcardiotomy VA ECMO patients.

A Clinical-Scale Microfluidic Respiratory Assist Device with 3D Branching Vascular Networks

Recent global events such as COVID-19 pandemic amid rising rates of chronic lung diseases highlight the need for safer, simpler, and more available treatments for respiratory failure, with increasing interest in extracorporeal membrane oxygenation (ECMO). A key factor limiting use of this technology is the complexity of the blood circuit, resulting in clotting and bleeding and necessitating treatment in specialized care centers. Microfluidic oxygenators represent a promising potential solution, but have not reached the scale or performance required for comparison with conventional hollow fiber membrane oxygenators (HFMOs). Here the development and demonstration of the first microfluidic respiratory assist device at a clinical scale is reported, demonstrating efficient oxygen transfer at blood flow rates of 750 mL min⁻1 , the highest ever reported for a microfluidic device. The central innovation of this technology is a fully 3D branching network of blood channels mimicking key features of the physiological microcirculation by avoiding anomalous blood flows that lead to thrombus formation and blood damage in conventional oxygenators. Low, stable blood pressure drop, low hemolysis, and consistent oxygen transfer, in 24-hour pilot large animal experiments are demonstrated - a key step toward translation of this technology to the clinic for treatment of a range of lung diseases.

Effects of shorter activated coagulation time on hemorrhage during venoarterial extracorporeal membrane oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been used for decades, but optimal anticoagulation control remains unknown. This study aimed to compare shorter target activated coagulation time (ACT) criteria with the usual target ACT criteria in terms of complications.

METHODS

We retrospectively identified patients who received ECMO between 1 January 2013 and 31 December 2018 in an acute tertiary care hospital. Patients were divided into two groups: (I) those whose target ACT was 160-180 sec and (II) those whose target ACT was 180-220 sec. Cox proportional hazard models and Fine-Gray models adjusted for propensity score to account for the competing risk of death were used to compare the incidence of hemorrhage during ECMO between the groups.

RESULTS

We identified 74 patients, 25 of whom were managed with target ACT 160-180 sec, and 49 of whom were managed with target ACT 180-220 sec. In crude analysis, the proportions of patients with hemorrhage in the under 180-sec group were significantly more than those in the over 180-sec group [60.0% (15/25) vs. 28.6% (14/49), p = 0.009]. Shorter target ACT was not associated with hemorrhage during ECMO in either Cox regression (hazard ratio, 1.67; 95% confidence interval, 0.59-4.80; p = 0.336) or Fine-Gray model (hazard ratio, 1.58; 95% confidence interval, 0.64-3.91; p = 0.324).

CONCLUSIONS

The shorter ACT target was not associated with improved hemorrhage and inappropriate coagulation than the usual target ACT criteria. This study is the first to compare the ACT target of patients with ECMO.

Surgical Science and the Evolution of Critical Care Medicine

Surgical science has driven innovation and inquiry across adult and pediatric disciplines that provide critical care regardless of location. Surgically originated but broadly applicable knowledge has been globally shared within the pages Critical Care Medicine over the last 50 years.

Extracorporeal Membrane Oxygenation (ECMO) for Pulmonary and/or Cardiopulmonary Support-a Brief Review and Our Experience

Extracorporeal membrane oxygenation (ECMO) is a modality utilized for partially or completely supporting the cardiac and/or pulmonary function. There are multiple vascular access techniques depending upon the necessity and the mode of ECMO used. ECMO has evolved over the years as an integral part of the cardiac care discipline. Historically, this lifesaving modality began as an extension of cardiopulmonary bypass and was associated with adverse outcomes. Currently, ECMO has evolved as an accepted and viable solution to patients with severe cardiac/respiratory/cardiorespiratory failure that is refractory to conservative management. The outcomes of patients on ECMO are dependent on multiple factors originating from demographic and pathophysiological status of patients as well as the control of homeostasis during ECMO within the acceptable range. Various studies have been published by many practitioners over past decades since the dawn of ECMO era. A brief review of such experience is summated, and a conclusion is derived about the clinical course of the patients on ECMO, while adding the author's experience about the same in a tertiary care large-volume center.

Updates in Neonatal Extracorporeal Membrane Oxygenation and the Artificial Placenta

Extracorporeal life support, initially performed in neonates, is now commonly used for both pediatric and adult patients requiring pulmonary and/or cardiac support. Data suggests the clinical feasibility of Extracorporeal Membrane Oxygenation for premature infants (29-33 weeks estimated gestational age [EGA]). For extremely premature infants less than 28 weeks EGA, an artificial placenta has been developed to recreate the fetal environment. This approach is investigational but clinical translation is promising. In this article, we discuss the current state and advances in neonatal and "preemie Extracorporeal Membrane Oxygenation" and the development of an artificial placenta and its potential use in extremely premature infants.

Changing populations being treated with ECMO in the neonatal period - who are the others?

Extracorporeal life support via extracorporeal membrane oxygenation (ECMO) has served the sickest of neonates for almost 50 years. Naturally, the characteristics of neonates receiving ECMO have changed. Advances in care have averted the need for ECMO for some, while complex cases with uncertain outcomes, previously not eligible for ECMO, are now considered. Characterizing the disease states and outcomes for neonates on ECMO is challenging as many infants do not fall into classic categories, i.e. meconium aspiration syndrome (MAS), respiratory distress syndrome (RDS), or congenital diaphragmatic hernia (CDH). Since 2017, over one third of neonatal respiratory ECMO runs reported to the Extracorporeal Life Support Organization Registry are grouped as Other, a catch-all that encompasses those with a diagnosis not included in the classic categories. This review summarizes the historical neonatal ECMO population, reviews advances in therapy and technology impacting neonatal care, and addresses the unknowns in the ever-growing category of Other.

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.

Multilayer Scaling of a Biomimetic Microfluidic Oxygenator

Extracorporeal membrane oxygenation (ECMO) has been advancing rapidly due to a combination of rising rates of acute and chronic lung diseases as well as significant improvements in the safety and efficacy of this therapeutic modality. However, the complexity of the ECMO blood circuit, and challenges with regard to clotting and bleeding, remain as barriers to further expansion of the technology. Recent advances in microfluidic fabrication techniques, devices, and systems present an opportunity to develop new solutions stemming from the ability to precisely maintain critical dimensions such as gas transfer membrane thickness and blood channel geometries, and to control levels of fluid shear within narrow ranges throughout the cartridge. Here, we present a physiologically inspired multilayer microfluidic oxygenator device that mimics physiologic blood flow patterns not only within individual layers but throughout a stacked device. Multiple layers of this microchannel device are integrated with a three-dimensional physiologically inspired distribution manifold that ensures smooth flow throughout the entire stacked device, including the critical entry and exit regions. We then demonstrate blood flows up to 200 ml/min in a multilayer device, with oxygen transfer rates capable of saturating venous blood, the highest of any microfluidic oxygenator, and a maximum blood flow rate of 480 ml/min in an eight-layer device, higher than any yet reported in a microfluidic device. Hemocompatibility and large animal studies utilizing these prototype devices are planned. Supplemental Visual Abstract, http://links.lww.com/ASAIO/A769.

Extracorporeal Membrane Oxygenation in Critically Ill Children

Neonatal and pediatric extracorporeal membrane oxygenation (ECMO) has evolved over the past 50 years. Advances in technology, expertise, and application have increased the number of centers providing ECMO with expanded indications for use. However, increasing the use of ECMO in recent years to more medically complex critically ill children has not changed overall survival despite increased experience and improvements in technology. This review focuses on ECMO history, circuits, indications and contraindications, management, complications, and outcome data. The authors highlight important areas of progress, including unintubated and awake patients on ECMO, application during the COVID-19 pandemic, and future directions.

Development of a Standardized Assessment of Simulation-based Extracorporeal Membrane Oxygenation Educational Courses

Background

In 2020, the Extracorporeal Life Support Organization education task force identified seven extracorporeal membrane oxygenation (ECMO) educational domains that would benefit from international collaborative efforts. These included research efforts to delineate the impact and outcomes of ECMO courses.

Objective

Development of a standardized online assessment tool to evaluate the effectiveness of didactic and simulation-based ECMO courses on participants’ confidence, knowledge, and simulation-based skills; participant satisfaction; and course educational benefits.

Methods

We performed a prospective multicenter observational study of five different U.S. academic institution–based adult ECMO courses that met Extracorporeal Life Support Organization endorsement requirements for course structure, educational content, and objectives. Standardized online forms were developed and administered before and after courses, assessing demographics, self-assessment regarding ECMO management, and knowledge examination (15 simple-recall multiple-choice questions). Psychomotor skill assessment was performed during the course (time to complete prespecified critical actions during simulation scenarios). Self-assessment evaluated cognitive, behavioral, and technical aspects of ECMO; course satisfaction; and educational benefits.

Results

Out of 211 participants, 107 completed both pre- and postcourse self-assessment forms (97 completed both pre- and postcourse knowledge forms). Fifty-three percent of respondents were physician intensivists, with most (51%) practicing at academic hospitals and with less than 1 year of ECMO experience (50%). After the course, participants reported significant increases in confidence across all domains (cognitive, technical, and behavioral, P < 0.0001, 95% confidence interval [CI], 1.2–1.5; P < 0.0001, 95% CI, 2.2–2.6; and P = 0.002, 95% CI, 1.7–2.1, respectively) with an increase in knowledge scores (P < 0.001; 95% CI, 1.4–2.5). These findings were most significant in participants with less ECMO experience. There were also significant reductions in times to critical actions in three of the four scored simulation scenarios. The results demonstrated participants’ satisfaction with most course aspects, with more than 95% expressing that courses met their educational goals.

Conclusion

We developed and tested a structured ECMO course assessment tool, demonstrating participants’ self-reported benefit as well as improvement in psychomotor skill acquisition, course satisfaction, and educational benefits. Course evaluation is feasible and potentially provides important information to improve ECMO courses. Future steps could include national implementation, addition of questions targeting clinical decision making to further assess knowledge gain, and multilanguage translation for implementation in international courses.

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.

Toward Development of a Higher Flow Rate Hemocompatible Biomimetic Microfluidic Blood Oxygenator

The recent emergence of microfluidic extracorporeal lung support technologies presents an opportunity to achieve high gas transfer efficiency and improved hemocompatibility relative to the current standard of care in extracorporeal membrane oxygenation (ECMO). However, a critical challenge in the field is the ability to scale these devices to clinically relevant blood flow rates, in part because the typically very low blood flow in a single layer of a microfluidic oxygenator device requires stacking of a logistically challenging number of layers. We have developed biomimetic microfluidic oxygenators for the past decade and report here on the development of a high-flow (30 mL/min) single-layer prototype, scalable to larger structures via stacking and assembly with blood distribution manifolds. Microfluidic oxygenators were designed with biomimetic in-layer blood distribution manifolds and arrays of parallel transfer channels, and were fabricated using high precision machined durable metal master molds and microreplication with silicone films, resulting in large area gas transfer devices. Oxygen transfer was evaluated by flowing 100% O2 at 100 mL/min and blood at 0-30 mL/min while monitoring increases in O2 partial pressures in the blood. This design resulted in an oxygen saturation increase from 65% to 95% at 20 mL/min and operation up to 30 mL/min in multiple devices, the highest value yet recorded in a single layer microfluidic device. In addition to evaluation of the device for blood oxygenation, a 6-h in vitro hemocompatibility test was conducted on devices (n = 5) at a 25 mL/min blood flow rate with heparinized swine donor blood against control circuits (n = 3). Initial hemocompatibility results indicate that this technology has the potential to benefit future applications in extracorporeal lung support technologies for acute lung injury.

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.

A high gas transfer efficiency microfluidic oxygenator for extracorporeal respiratory assist applications in critical care medicine

Advances in microfluidics technologies have spurred the development of a new generation of microfluidic respiratory assist devices, constructed using microfabrication techniques capable of producing microchannel dimensions similar to those found in human capillaries and gas transfer films in the same thickness range as the alveolar membrane. These devices have been tested in laboratory settings and in some cases in extracorporeal animal experiments, yet none have been advanced to human clinical studies. A major challenge in the development of microfluidic oxygenators is the difficulty in scaling the technology toward high blood flows necessary to support adult humans; such scaling efforts are often limited by the complexity of the fabrication process and the manner in which blood is distributed in a three-dimensional network of microchannels. Conceptually, a central advantage of microfluidic oxygenators over existing hollow-fiber membrane-based configurations is the potential for shallower channels and thinner gas transfer membranes, features that reduce oxygen diffusion distances, to result in a higher gas transfer efficiency defined as the ratio of the volume of oxygen transferred to the blood per unit time to the active surface area of the gas transfer membrane. If this ratio is not significantly higher than values reported for hollow fiber membrane oxygenators (HFMO), then the expected advantage of the microfluidic approach would not be realized in practice, potentially due to challenges encountered in blood distribution strategies when scaling microfluidic designs to higher flow rates. Here, we report on scaling of a microfluidic oxygenator design from 4 to 92 mL/min blood flow, within an order of magnitude of the flow rate required for neonatal applications. This scaled device is shown to have a gas transfer efficiency higher than any other reported system in the literature, including other microfluidic prototypes and commercial HFMO cartridges. While the high oxygen transfer efficiency is a promising advance toward clinical scaling of a microfluidic architecture, it is accompanied by an excessive blood pressure drop in the circuit, arising from a combination of shallow gas transfer channels and equally shallow distribution manifolds. Therefore, next-generation microfluidic oxygenators will require novel design and fabrication strategies to minimize pressure drops while maintaining very high oxygen transfer efficiencies.

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.

ECMO Retrieval over the Mediterranean Sea: Extending Hospital Arms

The retrieval and transport of patients from peripheral hospitals to high volume extracorporeal membrane oxygenation (ECMO) centers aims to reduce complications and improve survival. In Sicily (Italy), our institute houses a mobile ECMO team that serves a population of around 10 million people for a vast area in southern Italy and Malta. This observational, descriptive study includes all patients that required veno-venous (V-V) ECMO and transport by a mobile team between October 2009 and May 2020. Linear and multiple logistic regressions were applied to explore the risk factors for mortality in the ICU. Kaplan-Meier estimates were generated to predict the survival in patients transported by helicopter or ambulance, and the two cohorts were compared according to their baseline characteristics. Of 122 patients transported, 89 (73%) survived to ICU discharge (50 (41%) patients were transported by ambulance, and 72 (59%) were transported by helicopter). Independent predictive factors associated with mortality in a stepwise multiple regression model were prone positioning, acute kidney injury, and the number of days spent on mechanical ventilation (MV). Kaplan-Meier estimates for survival favored the helicopter cohort (79%) rather than the ambulance cohort (64%). Patients transported by helicopter had better pre-ECMO profiles, with shorter hospital and ICU stays, a shorter duration of MV use, and higher RESP scores, which indicate better survival probabilities. ECMO transport can be carried out safely over long distances; in rural areas with underdeveloped roads, transportation via helicopter or ambulance can extend the arm of the hospital to remote areas. Early ECMO initiation can be crucial in improving survival outcomes, and when transportation is the limiting factor to starting ECMO support, it should be attempted at the earliest logistical stage possible.

Pediatric and neonatal extracorporeal life support: current state and continuing evolution

The use of extracorporeal life support (ECLS) for the pediatric and neonatal population continues to grow. At the same time, there have been dramatic improvements in the technology and safety of ECLS that have broadened the scope of its application. This article will review the evolving landscape of ECLS, including its expanding indications and shrinking contraindications. It will also describe traditional and hybrid cannulation strategies as well as changes in circuit components such as servo regulation, non-thrombogenic surfaces, and paracorporeal lung-assist devices. Finally, it will outline the modern approach to managing a patient on ECLS, including anticoagulation, sedation, rehabilitation, nutrition, and staffing.

Clinical characteristics and outcomes of adults with peripheral extracorporeal membrane oxygenation in a developing country: A single center 8-year retrospective study

INTRODUCTION

In our institute, we began using peripheral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) in 2010, and peripheral veno-venous (VV) ECMO in 2015. This study aimed to describe clinical characteristics and outcomes in those patients.

METHODS

We reviewed retrospective data of adults receiving peripheral ECMO from January 2010 to December 2017 and divided it into two groups for analysis: VA- and VV-ECMO.

RESULTS

There were 28 patients in the VA group and 12 in VV. For VA, the mean (SD) age was 58.5 (17.2) years. The most common indication was cardiac arrest (12 patients, 42.9%); 15 patients (53.6%) were on intra-aortic balloon pump concomitantly. In the VV cohort, the mean age was 53.3 (16.2) years. Eleven (91.7%) patients had acute respiratory distress syndrome as an indication. The mortality rate of VA-ECMO was 85.7%, and VV was 58.3%.

CONCLUSION

The mortality rate in our ECMO center was considerably higher than that in the international registry report. Improved team education, rigid patient selection criteria, and a reimbursement protocol should lead to ameliorated outcomes.

TRIAL REGISTRATION

TCTR20190120001. Registered January 19, 2019.

Extracorporeal Membrane Oxygenation for Hemodynamic Support

Extracorporeal membrane oxygenation was first successfully achieved in 1975 in a neonate with meconium aspiration. Neonatal extracorporeal membrane oxygenation has expanded to include hemodynamic support in cardiovascular collapse before and after cardiac surgery, medical heart disease, and rescue therapy for cardiac arrest. Advances in pump technology, circuit biocompatibility, and oxygenators efficiency have allowed extracorporeal membrane oxygenation to support neonates with increasingly complex pathophysiology. Contraindications include extreme prematurity, extremely low birth weight, lethal chromosomal abnormalities, uncontrollable hemorrhage, uncontrollable disseminated intravascular coagulopathy, and severe irreversible brain injury. The future will involve collaboration to guide and evolve evidence-based practices for this life-sustaining therapy.

Trends in Mortality and Costs of Pediatric Extracorporeal Life Support

BACKGROUND

Extracorporeal life support (ECLS) has been used for >30 years as a life-sustaining therapy in critically ill patients for a variety of indications. In the current study, we aimed to examine trends in use, mortality, length of stay (LOS), and costs for pediatric ECLS hospitalizations.

METHODS

We performed a retrospective cohort study of pediatric patients (between the ages of 28 days and <21 years) on ECLS using the 2008-2015 National Inpatient Sample, the largest all-payer inpatient hospitalization database generated from hospital discharges. Nonparametric and Cochran-Armitage tests for trend were used to study in-hospital mortality, LOS, and hospitalization costs.

RESULTS

Of the estimated 5847 patients identified and included for analysis, ECLS was required for respiratory failure (36.4%), postcardiotomy syndrome (25.9%), mixed cardiopulmonary failure (21.7%), cardiogenic shock (13.1%), and transplanted graft dysfunction (2.9%). The rate of ECLS hospitalizations increased 329%, from 11 to 46 cases per 100 000 pediatric hospitalizations, from 2008 to 2015 (P < .001). Overall mortality decreased from 50.3% to 34.6% (P < .001). Adjusted hospital costs increased significantly ($214 046 ± 11 822 to 324 841 ± 25 621; P = .002) during the study period despite a stable overall hospital LOS (46 ± 6 to 44 ± 4 days; P = .94).

CONCLUSIONS

Use of ECLS in pediatric patients has increased with substantially improved ECLS survival rates. Hospital costs have increased significantly despite a stable LOS in this group. Dissemination of this costly yet life-saving technology warrants ongoing analysis of use trends to identify areas for quality improvement.

Extracorporeal Membrane Oxygenation for Respiratory Failure

This review focuses on the use of veno-venous extracorporeal membrane oxygenation for respiratory failure across all blood flow ranges. Starting with a short overview of historical development, aspects of the physiology of gas exchange (i.e., oxygenation and decarboxylation) during extracorporeal circulation are discussed. The mechanisms of phenomena such as recirculation and shunt playing an important role in daily clinical practice are explained.Treatment of refractory and symptomatic hypoxemic respiratory failure (e.g., acute respiratory distress syndrome [ARDS]) currently represents the main indication for high-flow veno-venous-extracorporeal membrane oxygenation. On the other hand, lower-flow extracorporeal carbon dioxide removal might potentially help to avoid or attenuate ventilator-induced lung injury by allowing reduction of the energy load (i.e., driving pressure, mechanical power) transmitted to the lungs during mechanical ventilation or spontaneous ventilation. In the latter context, extracorporeal carbon dioxide removal plays an emerging role in the treatment of chronic obstructive pulmonary disease patients during acute exacerbations. Both applications of extracorporeal lung support raise important ethical considerations, such as likelihood of ultimate futility and end-of-life decision-making. The review concludes with a brief overview of potential technical developments and persistent challenges.

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.

Extra-Corporeal Membrane Oxygenation for Neonatal Respiratory Support

To review our experience with Extra-Corporeal Membrane Oxygenation (ECMO) for respiratory support in neonates. From 1989 to 2018 2114 patients underwent respiratory ECMO support, with 764 (36%) neonates. Veno-Venous (V-V) cannulation was used in 428 (56%) neonates and Veno-Arterial (V-A) in 336 (44%). Historically V-V ECMO was our preferred modality, but due to lack of suitable cannula in the last 7 years V-A was used in 209/228 (92%) neonates. Mean and inter-quartile range of ECMO duration was 117 hours (inter-quartile range 90 to 164 hours). Overall 724 (95%) neonates survived to ECMO decannulation, with 640 (84%) hospital discharge. Survival varied with underlying diagnosis: meconium aspiration 98% (354/362), persistent pulmonary hypertension 80% (120/151), congenital diaphragmatic hernia 66% (82/124), sepsis 59% (35/59), pneumonia 86% (6/7), other 71% (43/61). Survival was 86% with V-V and 80% with V-A cannulation, better than ELSO Registry with 77% V-V and 63% V-A. Major complications: cerebral infarction/hemorrhage in 4.7% (31.1% survival to discharge), renal replacement therapy in 17.6% (58.1% survival to discharge), new infection in 2.9%, with negative impact on survival (30%). Following a circuit design modification and subsequent reduction in heparin requirement, intracerebral hemorrhage decreased to 9/299 (3.0%) radiologically proven cerebral infarction/hemorrhage. We concluded (1) outcomes from neonatal ECMO in our large case series were excellent, with better survival and lower complication rate than reported in ELSO registry. (2) These results highlight the benefits of ECMO service in high volume units. (3) The similar survival rate seen in neonates with V-A and V-V cannulation differs from the ELSO register; this may reflect the change in cannulation enforced by lack of suitable V-V cannula and all neonates undergoing V-A cannulation.

Adjunctive Therapies During Extracorporeal Membrane Oxygenation to Enhance Multiple Organ Support in Critically Ill Children

Since the advent of extracorporeal membrane oxygenation (ECMO) over 40 years ago, there has been increasing interest in the use of the extracorporeal circuit as a platform for providing multiple organ support. In this review, we will examine the evidence for the use of continuous renal replacement therapy, therapeutic plasma exchange, leukopheresis, adsorptive therapies, and extracorporeal liver support in conjunction with ECMO.