The evolution of patient selection criteria and indications for extracorporeal life support in pediatric cardiopulmonary failure: next time, let's not eat the bones

Refurbishment of Extracorporeal Life Support Oxygenators in the Context of In Vitro Testing

Refurbishing single use extracorporeal membrane oxygenation (ECMO) oxygenators for in vitro research applications is common. However, the refurbishment protocols that are established in respective laboratories have never been evaluated. In the present study, we aim at proving the relevance of a well-designed refurbishing protocol by quantifying the burden of repeatedly reused oxygenators. We used the same three oxygenators in 5 days of 6 hours whole blood experiments. During each experiment day, the performance of the oxygenators was measured through the evaluation of gas transfer. Between experiment days, each oxygenator was refurbished applying three alternative refurbishment protocols based on purified water, pepsin and citric acid, and hydrogen peroxide solutions, respectively. After the last experiment day, we disassembled the oxygenators for visual inspection of the fiber mats. The refurbishment protocol based on purified water showed strong degeneration with a 40-50 %-performance drop and clearly visible debris on the fiber mats. Hydrogen peroxide performed better; nevertheless, it suffered a 20% decrease in gas transfer as well as clearly visible debris. Pepsin/citric acid performed best in the field, but also suffered from 10% performance loss and very few, but visible debris. The study showed the relevance of a well-suited and well-designed refurbishment protocol. The distinct debris on the fiber mats also suggests that reusing oxygenators is ill-advised for many experiment series, especially regarding hemocompatibility and in vivo testing. Most of all, this study revealed the relevance of stating the status of test oxygenators and, if refurbished, comment on the implemented refurbishment protocol in detail.

Basics of Extracorporeal Membrane Oxygenation

OVERVIEW

The use of extracorporeal membrane oxygenation (ECMO) is becoming commonplace worldwide in ICUs for the care of patients with respiratory and/or cardiac failure. Understanding the use of ECMO and the management of these complex patients will be vital to current and future clinicians as ECMO use continues to grow.

Risk Factors for Mortality in Refractory Pediatric Septic Shock Supported with Extracorporeal Life Support

Risk factors for mortality in children with refractory pediatric septic shock who are supported with extracorporeal life support (ECLS) are largely unknown. Therefore, we performed univariable and multivariable analyses to determine risk factors for mortality among children (<19 years) who underwent an ECLS run between January 2012 and September 2014 at eight tertiary pediatric hospitals, and who had septic shock based on 2005 International Consensus Criteria. Of the 514 children treated with ECLS during the study period, 70 were identified with septic shock. The mortality rate was similar between those with (54.3%) and without septic shock (43.7%). Among those with septic shock, significant risk factors for mortality included cardiac failure or extracorporeal cardiopulmonary resuscitation (ECPR) as indication for ECLS cannulation compared with respiratory failure (P = 0.003), having a new neurologic event following cannulation (P = 0.032), acquiring a new infection following cannulation (P = 0.005), inability to normalize pH in the 48 hours following ECLS cannulation (P = 0.010), and requiring higher daily volume of platelet transfusions (P = 0.005). These findings can be used to help guide clinical decision making for children with septic shock that is refractory to medical management.

Extracorporeal Membrane Oxygenation for Severe Respiratory Failure During Respiratory Epidemics and Pandemics: A Narrative Review

Introduction: Epidemics and pandemics from zoonotic respiratory viruses, such as the 2019 novel coronavirus, can lead to significant global intensive care burden as patients progress to acute respiratory distress syndrome (ARDS). A subset of these patients develops refractory hypoxaemia despite maximal conventional mechanical ventilation and require extracorporeal membrane oxygenation (ECMO). This review focuses on considerations for ventilatory strategies, infection control and patient selection related to ECMO for ARDS in a pandemic. We also summarise the experiences with ECMO in previous respiratory pandemics. Materials and Methods: A review of pertinent studies was conducted via a search using MEDLINE, EMBASE and Google Scholar. References of articles were also examined to identify other relevant publications. Results: Since the H1N1 Influenza pandemic in 2009, the use of ECMO for ARDS continues to grow despite limitations in evidence for survival benefit. There is emerging evidence to suggest that lung protective ventilation for ARDS can be further optimised while receiving ECMO so as to minimise ventilator-induced lung injury and subsequent contributions to multi-organ failure. Efforts to improve outcomes should also encompass appropriate infection control measures to reduce co-infections and prevent nosocomial transmission of novel respiratory viruses. Patient selection for ECMO in a pandemic can be challenging. We discuss important ethical considerations and predictive scoring systems that may assist clinical decision-making to optimise resource allocation. Conclusion: The role of ECMO in managing ARDS during respiratory pandemics continues to grow. This is supported by efforts to redefine optimal ventilatory strategies, reinforce infection control measures and enhance patient selection. Ann Acad Med Singapore 2020;49:199–214 Key words: Acute Respiratory Distress Syndrome, Coronavirus disease 2019, ECMO, Infection control, Mechanical ventilation

Successful venoarterial extracorporeal membrane oxygenation for postoperative septic shock in a child with liver transplantation: A case report

Refractory septic shock after LT is a life-threatening complication. VA ECMO is used to treat refractory cardiorespiratory failure. We present herein the case of a 5-year-old girl with post-Kasai biliary atresia, who underwent a living donor LT and suffered refractory septic shock. VA ECMO was indicated due to progressive cardiac deterioration. After full recovery of her EF, she has been steadily improving and has shown good liver function and no neurological sequelae. This is the first report of successful VA ECMO in a post- LT patient with refractory septic shock.

Ethical Considerations for Care of the Child Undergoing Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) is a complex, highly technical surgical procedure that can offer hope for children born with congenital heart defects. The procedure may only briefly prolong a life, has limited potential for decreasing mortality, and may lead to serious complications, however. Perioperative nurses play an important role in caring for the child who requires ECMO. They are involved in assessing the child, implementing the plan of care, and facilitating communication between the child's family members and the health care team. Thus, perioperative nurses have a responsibility to consider the broad range of ethical issues associated with the procedure. By examining the ethical concepts of beneficence, nonmaleficence, autonomy, justice, and moral distress, the perioperative nurse can better understand the dilemmas that can affect the care and outcome of the critically ill child who requires ECMO.

Should Extracorporeal Membrane Oxygenation Be Offered? An International Survey

OBJECTIVES

To assess the current attitudes of extracorporeal membrane oxygenation (ECMO) program directors regarding eligibility for ECMO among children with cardiopulmonary failure.

STUDY DESIGN

Electronic cross-sectional survey of ECMO program directors at ECMO centers worldwide within the Extracorporeal Life Support Organization directory (October 2015-December 2015).

RESULTS

Of 733 eligible respondents, 226 (31%) completed the survey, 65% of whom routinely cared for pediatric patients. There was wide variability in whether respondents would offer ECMO to any of the 5 scenario patients, ranging from 31% who would offer ECMO to a child with trisomy 18 to 76% who would offer ECMO to a child with prolonged cardiac arrest and indeterminate neurologic status. Even physicians practicing the same specialty sometimes held widely divergent opinions, with 50% of pediatric intensivists stating they would offer ECMO to a child with severe developmental delay and 50% stating they would not. Factors such as quality of life and neurologic status influenced decision making and were used to support decisions for and against offering ECMO.

CONCLUSIONS

ECMO program directors vary widely in whether they would offer ECMO to various children with cardiopulmonary failure. This heterogeneity in physician decision making underscores the need for more evidence that could eventually inform interinstitutional guidelines regarding patient selection for ECMO.

Severe Tumor Lysis Syndrome and Acute Pulmonary Edema Requiring Extracorporeal Membrane Oxygenation Following Initiation of Chemotherapy for Metastatic Alveolar Rhabdomyosarcoma

We present an 8-year-old male with metastatic alveolar rhabdomyosarcoma (ARMS) who developed precipitous cardiopulmonary collapse with severe tumor lysis syndrome (TLS) 48 hr after initiation of chemotherapy. Despite no detectable pulmonary metastases, acute hypoxemic respiratory failure developed, requiring extracorporeal membrane oxygenation (ECMO). Although TLS has been reported in disseminated ARMS, this singular case of life-threatening respiratory deterioration developing after initiation of chemotherapy presented unique therapeutic dilemmas. We review the clinical aspects of this case, including possible mechanisms of respiratory failure, and discuss the role of ECMO utilization in pediatric oncology.

Outcomes of pediatric patients with abdominal sepsis requiring surgery and extracorporeal membrane oxygenation using the Extracorporeal Life Support Organization database

No study describes the use of extracorporeal membrane oxygenation (ECMO) in pediatric patients with abdominal sepsis (AS) requiring surgery. A description of outcomes in this patient population would assist clinical decision-making and provide a context for discussions with patients and families. The Extracorporeal Life Support Organization database was queried for pediatric patients (30 days to 18 years) with AS requiring surgery. Forty-five of 61 patients survived (73.8%). Reported bleeding complications (57.1 vs 48.8%), the number of pre-ECMO ventilator hours (208.1 vs 178.9), and the timing of surgery before (50 vs 66.7%) and on-ECMO (50 vs 26.7%) were similar in survivors and nonsurvivors. Decreased pre-ECMO mean pH (7.1 vs 7.3) was associated with increased mortality (odds ratio, 1.49; 95% confidence interval, 1.04 to 2.14). ECMO use for pediatric patients with AS requiring surgery is associated with increased mortality and an increased rate of bleeding complications compared with all pediatric patients receiving ECMO support. Acidemia predicts mortality and provides a potential target of examination for future studies.

Outcomes of Pediatric Patients with Abdominal Sepsis Requiring Surgery and Extracorporeal Membrane Oxygenation Using the Extracorporeal Life Support Organization Database

No study describes the use of extracorporeal membrane oxygenation (ECMO) in pediatric patients with abdominal sepsis (AS) requiring surgery. A description of outcomes in this patient population would assist clinical decision-making and provide a context for discussions with patients and families. The Extracorporeal Life Support Organization database was queried for pediatric patients (30 days to 18 years) with AS requiring surgery. Forty-five of 61 patients survived (73.8%). Reported bleeding complications (57.1 vs 48.8%), the number of pre-ECMO ventilator hours (208.1 vs 178.9), and the timing of surgery before (50 vs 66.7%) and on-ECMO (50 vs 26.7%) were similar in survivors and nonsurvivors. Decreased pre-ECMO mean pH (7.1 vs 7.3) was associated with increased mortality (odds ratio, 1.49; 95% confidence interval, 1.04 to 2.14). ECMO use for pediatric patients with AS requiring surgery is associated with increased mortality and an increased rate of bleeding complications compared with all pediatric patients receiving ECMO support. Acidemia predicts mortality and provides a potential target of examination for future studies.

Bronchoscopy with N-acetylcysteine lavage in severe respiratory failure from pertussis infection

Pertussis is an illness that causes significant morbidity and mortality, especially in infants younger than 3 months old. In the most severe cases, it can cause pneumonia, respiratory failure, acute respiratory distress syndrome, pulmonary hypertension, and death. There are reports of using rescue extracorporeal membrane oxygenation (ECMO) as a rescue therapy. However, the mortality of ECMO with pertussis is higher than with other causes of pediatric respiratory failure. We report here the case of a 2-month-old boy with severe respiratory failure and pulmonary hypertension who satisfied ECMO criteria but was successfully treated with repeated bronchoscopy with instillation of N-acetylcysteine. Our patient's respiratory failure was refractory to multiple therapies that have shown benefit in pediatric hypoxemic respiratory failure, including open lung strategies, prone positioning, intratracheal surfactant, and inhaled nitric oxide. Although pulmonary hypertension is a key factor in most cases of fatal pertussis, the adverse effects of hyperinflation and air leaks were more important in this patient's clinical course. Because bronchiolar obstruction from inflammatory, mucous, and airway epithelial debris can be seen in severe pertussis, a regimen of repeated therapeutic bronchoscopy was initiated, and thick, inspissated secretions were retrieved. The patient's airway obstruction gradually resolved, and he eventually recovered with minimal sequelae.

Clinical management of the extracorporeal membrane oxygenation circuit

The clinical management of patients on extracorporeal membrane oxygenation should be standardized and follow clear guidelines or protocols. However, due to the diversity of cannulation strategies and the complex situations that extracorporeal membrane oxygenation is now used in, each extracorporeal membrane oxygenation program has developed its own clinical management strategies. These vary widely across the globe. Extracorporeal membrane oxygenation provides partial or complete support of ventilation and oxygenation, as well as univentricular or biventricular support of myocardial function, either individually or in combination. High-flow extracorporeal membrane oxygenation can also provide circulatory support in profound vasoplegic shock. Improvements in technology and greater understanding of disease pathophysiology, coupled to refinements in technology, which lessen the adverse interaction between the circuit and the patient, all contribute to fewer mechanical and patient complications on extracorporeal membrane oxygenation. Earlier and more appropriate use of extracorporeal membrane oxygenation has been associated with improved patient outcomes. These clinical management strategies are reviewed in this article, part of the Pediatric Cardiac Intensive Care Society/Extracorporeal Life Support Organization Joint Statement on Mechanical Circulatory Support.

Extracorporeal life support: an update of Rogers' Textbook of Pediatric Intensive Care

INTRODUCTION

The field of extracorporeal life support, which has focused predominantly on extracorporeal membrane oxygenation in the past, is undergoing rapid expansion following years of stagnation as newer devices and improved technology have become available. Additionally, new cannulae and cannulation techniques have allowed extracorporeal life support to be expanded to many groups who would have been excluded from support in the past.

REVIEW

This update will review the current state of the art since Rogers' Textbook of Pediatric Intensive Care (Fourth Edition) was published several years ago. The changing environment of extracorporeal support in terms of patient populations, technological advances, patient management, and outcome will be discussed.

CONCLUSIONS

Continued examination of the criteria and circumstances where extracorporeal life support is applied as well as outcomes which include morbidity, cost effectiveness, and quality of life are needed areas of continued research. Increasing collaborations between all centers performing extracorporeal life support throughout the world should remain a priority to further research and understanding of this complex field.