Outcome of pediatric patients treated with extracorporeal life support after cardiac surgery

Early outcomes of moderate-to-high-risk pediatric congenital cardiac surgery and predictors of extracorporeal circulatory life support requirement

Background

Cardiopulmonary failure refractory to medical management after moderate-to-high-risk congenital cardiac surgery may necessitate mechanical support with veno-arterial extracorporeal membrane oxygenation (ECMO). On the extreme, ECMO can also be initiated in the setting of cardiac arrest (extracorporeal cardiopulmonary resuscitation, ECPR) unresponsive to conventional resuscitative measures.

Methods

This was a single-center retrospective cohort study of patients (n = 510) aged <3 years old who underwent cardiac surgery with cardiopulmonary bypass with a RACHS-1 score ≥3 between 2011 and 2014. Perioperative factors were reviewed to identify predictors of ECMO initiation and mortality in the operating room (OR) and the intensive care unit (ICU).

Results

A total of 510 patients with a mean surgical age of 10.0 ± 13.4 months were included. Among them, 21 (4%) patients received postoperative ECMO-12 were initiated in the OR and 9 in the ICU. ECMO cannulation was associated with cardiopulmonary bypass duration, aortopulmonary shunt, residual severe mitral regurgitation, vaso-inotropic score, and postprocedural lactate (p < 0.001). Of the 32 (6%) total deaths, 7 (22%) were ECMO patients-4 were elective OR cannulations and 3 were ICU ECPR. Prematurity [hazard ratio (HR): 2.61, p < 0.01), Norwood or Damus-Kaye-Stansel procedure (HR: 4.29, p < 0.001), postoperative left ventricular dysfunction (HR: 5.10, p = 0.01), residual severe tricuspid regurgitation (HR: 6.06, p < 0.001), and postoperative ECMO (ECPR: HR: 15.42, p < 0.001 vs. elective: HR: 5.26, p = 0.01) were associated with mortality. The two patients who were electively cannulated in the ICU survived.

Discussion

Although uncommon, postoperative ECMO in children after congenital cardiac surgery is associated with high mortality, especially in cases of ECPR. Patients with long cardiopulmonary bypass time, residual cardiac lesions, or increased vaso-inotropic requirement are at higher risk of receiving ECMO. Pre-emptive or early ECMO initiation before deterioration into cardiac arrest may improve survival.

Short-Term Mortality Among Pediatric Patients With Heart Diseases Undergoing Veno-Arterial Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Analysis

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation serves as a crucial mechanical circulatory support for pediatric patients with severe heart diseases, but the mortality rate remains high. The objective of this study was to assess the short-term mortality in these patients.

METHODS AND RESULTS

We systematically searched PubMed, Embase, and Cochrane Library for observational studies that evaluated the short-term mortality of pediatric patients undergoing veno-arterial extracorporeal membrane oxygenation. To estimate short-term mortality, we used random-effects meta-analysis. Furthermore, we conducted meta-regression and binomial regression analyses to investigate the risk factors associated with the outcome of interest. We systematically reviewed 28 eligible references encompassing a total of 1736 patients. The pooled analysis demonstrated a short-term mortality (defined as in-hospital or 30-day mortality) of 45.6% (95% CI, 38.7%-52.4%). We found a significant difference (P<0.001) in mortality rates between acute fulminant myocarditis and congenital heart disease, with acute fulminant myocarditis exhibiting a lower mortality rate. Our findings revealed a negative correlation between older age and weight and short-term mortality in patients undergoing veno-arterial extracorporeal membrane oxygenation. Male sex, bleeding, renal damage, and central cannulation were associated with an increased risk of short-term mortality.

CONCLUSIONS

The short-term mortality among pediatric patients undergoing veno-arterial extracorporeal membrane oxygenation for severe heart diseases was 45.6%. Patients with acute fulminant myocarditis exhibited more favorable survival rates compared with those with congenital heart disease. Several risk factors, including male sex, bleeding, renal damage, and central cannulation contributed to an increased risk of short-term mortality. Conversely, older age and greater weight appeared to be protective factors.

Optimizing Outcomes in Extracorporeal Membrane Oxygenation Postcardiotomy in Pediatric Population

Extracorporeal membrane oxygenation (ECMO) is a rapidly emerging advanced life support technique used in cardiorespiratory failure refractory to other treatments. There has been an influx in the number of studies relating to ECMO in recent years, as the technique becomes more popular. However, there are still significant gaps in the literature including complications and their impacts and methods to predict their development. This review evaluates the available literature on the complications of ECMO postcardiotomy in the pediatric population. Areas explored include renal, cardiovascular, hematological, infection, neurological, and hepatic complications. Incidence, risk factors and potential predictors, and scoring systems for the development of these complications have been evaluated.

The numerical value of fluid balance to predict survival in neonates requiring extracorporeal membrane oxygenation

BACKGROUND

The aim of this study was to understand numerical variation of fluid balance in neonates requiring extracorporeal membrane oxygenation (ECMO) and to assess the relationship between hourly fluid balance and mortality.

METHODS

This is a prospective cohort study. All neonates supported by ECMO were enrolled from October 2011 to September 2017. All of the enrolled neonates were divided into survival group and non- survival group. The numerical value of fluid balance of the enrolled neonates were recorded at 6 hours, 12 hours, 24 hours, 36 hours and 48 hours after initiation of ECMO respectively. The differences between the two groups were compared. The numerical value of fluid balance predict survival by the receiver operating characteristic (ROC) curve.

RESULTS

Forty-eight neonates were enrolled, in which 35 cases were survival and the survival rate was 72.9%. The numerical value of fluid balance in the survival group were lower than that in the non-survival group at 6 hours, 12 hours, 24 hours, 36 hours and 48 hours after ECMO(all P<0.05). The area under ROC curve at 6h, 12h, 24h, 36h and 48h after initiation of ECMO was 0.835, 0.900, 0.839, 0.909 and 0.974 respectively. There were statistically significant in the numerical value of fluid balance predicting survival (all P<0.05) and a high sensitivity, specificity and positive predictive value at the each time point.

CONCLUSIONS

The negative hourly fluid balance were associated with decreased mortality, and the lower the numerical value of fluid balance in neonates requiring ECMO, the higher the survival rate.

Hemodynamic and Echocardiographic Predictors of Mortality in Pediatric Patients on Venoarterial Extracorporeal Membrane Oxygenation: A Multicenter Investigation

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (ECMO) supports patients with advanced cardiac dysfunction; however, mortality occurs in a significant subset of patients. The authors performed a multicenter, prospective study to determine hemodynamic and echocardiographic predictors of mortality in children placed on ECMO for cardiac support.

METHODS

Over 8 years, six heart centers prospectively assessed echocardiographic and hemodynamic variables on full and minimum ECMO flow. Sixty-three patients were enrolled, ranging in age from 1 day to 16 years. Hemodynamic measurements included heart rate, vasoactive inotropic score, arteriovenous oxygen difference, pulse pressure, and lactate. Echocardiographic variables included shortening fraction, ejection fraction (EF), right ventricular fractional area change, outflow tract Doppler-derived stroke distance (velocity-time integral [VTI]), and degree of atrioventricular valve regurgitation. Patients were stratified into two groups: those who were able to wean within 48 hours of assessment and survived without ventricular assist devices or orthotopic heart transplantation (successful wean group) and those with unsuccessful weaning. For each patient, variables were compared between full and minimum ECMO flow for each group.

RESULTS

Thirty-eight patients (60%) formed the unsuccessful group (two with ventricular assist devices, four with orthotopic heart transplantation, 24 deaths), and 25 constituted the successful wean group. At minimum flow, higher EF (53 ± 16% vs 40 ± 20%, P = .0094), less mitral regurgitation (0.8 ± 0.9 vs 1.4 ± 0.9, P = .0329), and lower central venous pressure (12.0 ± 3.9 vs 14.7 ± 5.4 mm Hg), along with higher VTI (9.0 ± 2.9 vs 6.8 ± 3.7 cm, P = .0154), correlated successful weaning. A longer duration of ECMO (8 vs 5 days, P < .0002) was associated with unsuccessful weaning. Multivariate logistic regression predicted minimum-flow EF and VTI to independently predict successful weaning with cutoff values by receiver operating characteristic analysis of EF > 41% (area under the curve, 0.712; P = .0005) and VTI > 7.9 cm (area under the curve, 0.729; P = .0010).

CONCLUSIONS

Diminished VTI or EF during ECMO weaning predicts the need for orthotopic heart transplantation or ventricular assist device support or death in children on ECMO for cardiac dysfunction. Increased postwean central venous pressure or mitral regurgitation along with a prolonged ECMO course also predicted these adverse outcomes. These measurements should be used to help discriminate which patients will require alternative methods of circulatory support for survival.

Bridging with Veno-Arterial Extracorporeal Membrane Oxygenation in Children: A 10-Year Single-Center Experience

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is frequently used in children with and without congenital heart disease (CHD). This study, of a single-center and retrospective design, evaluated the use and timing of V-A ECMO in a pediatric cohort who underwent V-A ECMO implantation between January 2009 and December 2019. The patients were divided into a pre-/non-surgical group and a post-surgical group. Among the investigated variables were age, gender, weight, duration of ECMO, ECMO indication, and ventricular physiology, with only the latter being statistically relevant between the two groups. A total of 111 children (58 male/53 female), with a median age of 87 days (IQR: 7–623) were supported using V-A ECMO. The pre-/non-surgical group consisted of 59 patients and the post-surgical group of 52 patients. Survival at discharge was 49% for the pre-/non-surgical group and 21% for the surgical group (p = 0.04). Single-ventricle physiology was significant for a worse outcome (p = 0.0193). Heart anatomy still has the biggest role in the outcomes of children on ECMO. Nevertheless, children with CHD can be successfully bridged with ECMO to cardiac operation.

Extracorporeal Membrane Oxygenation in Congenital Heart Disease

Mechanical circulatory support (MCS) is a key therapy in the management of patients with severe cardiac disease or respiratory failure. There are two major forms of MCS commonly employed in the pediatric population—extracorporeal membrane oxygenation (ECMO) and ventricular assist device (VAD). These modalities have overlapping but distinct roles in the management of pediatric patients with severe cardiopulmonary compromise. The use of ECMO to provide circulatory support arose from the development of the first membrane oxygenator by George Clowes in 1957, and subsequent incorporation into pediatric cardiopulmonary bypass (CPB) by Dorson and colleagues. The first successful application of ECMO in children with congenital heart disease undergoing cardiac surgery was reported by Baffes et al. in 1970. For the ensuing nearly two decades, ECMO was performed sparingly and only in specialized centers with varying degrees of success. The formation of the Extracorporeal Life Support Organization (ELSO) in 1989 allowed for the collation of ECMO-related data across multiple centers for the first time. This facilitated development of consensus guidelines for the use of ECMO in various populations. Coupled with improving ECMO technology, these advances resulted in significant improvements in ECMO utilization, morbidity, and mortality. This article will review the use of ECMO in children with congenital heart disease.

Postcardiotomy Extracorporeal Membrane Oxygenation Support in Patients with Congenital Heart Disease

Background

This study investigated mortality and morbidity in patients requiring post-cardiotomy extracorporeal membrane oxygenation (ECMO) support after operations for congenital heart disease (CHD).

Methods

CHD patients requiring postoperative ECMO support between May 2011 and May 2021 were retrospectively reviewed. Patients were divided into non-survivors and survivors to hospital discharge. Survival outcomes and associations of various factors with in-hospital death were analyzed.

Results

Fifty patients required postoperative ECMO support. Patients' median age and weight at the time of ECMO insertion were 1.85 months (interquartile range [IQR], 0.23-14.5 months) and 3.84 kg (IQR, 3.08-7.88 kg), respectively. Twenty-nine patients (58%) were male. The median duration of ECMO support was 6 days (IQR, 3-12 days). Twenty-nine patients (58%) died on ECMO support or after ECMO weaning, and 21 (42%) survived to hospital discharge. Postoperative complications included renal failure (n=33, 66%), bleeding (n=11, 22%), and sepsis (n=15, 30%). Prolonged ECMO support (p=0.017), renal failure (p=0.005), continuous renal replacement therapy (CRRT) application (p=0.001), sepsis (p=0.012), bleeding (p=0.032), and high serum lactate (p=0.002) and total bilirubin (p=0.017) levels during ECMO support were associated with higher mortality risk in a univariate analysis. A multivariable analysis identified CRRT application (p=0.013) and a high serum total bilirubin level (p=0.001) as independent risk factors for death.

Conclusion

Postcardiotomy ECMO should be considered as an important therapeutic modality for patients unresponsive to conventional management. ECMO implementation strategies and management in appropriate patients without severe complications, particularly renal failure and/or liver failure, are crucial for achieving positive outcomes.

Outcomes in Pediatric Post-Cardiotomy ECMO Support With Modification of Systematic Support Strategy

BACKGROUND

Utilization of extracorporeal membrane oxygenation (ECMO) support in the post-cardiotomy setting is vital to successful perioperative outcomes following pediatric cardiac surgery. Specific analysis of protocolized management strategies and staff preparedness is imperative to optimizing institutional ECMO outcomes.

METHODS

All patients requiring post-cardiotomy ECMO support at a single institution from 2013 to 2019 were retrospectively reviewed. In 2015, several modifications were made to the ECMO support paradigm that addressed deficiencies in equipment, critical care protocols, and staff preparedness. Cases were stratified according to era of ECMO support; patients supported prior to paradigm change from 2013 to 2015 (Group EARLY, n = 20), and patients supported following the implementation of systematic modifications from 2016 to 2019 (Group LATE, n = 26). The primary outcomes of interest were survival to decannulation and hospital discharge.

RESULTS

Median age at cannulation was 24.5 days (IQR 7-96) and median duration of support was 4 days (IQR 2-8). Overall survival to decannulation was 78.3% (65% EARLY vs. 88.5% LATE, P = .08) and overall survival to hospital discharge was 58.7% (35% EARLY vs. 76.9% LATE, P = .004).

CONCLUSION

Systematic modifications to ECMO support strategy and staff preparation are associated with a significant increase in perioperative survival for pediatric patients requiring post-cardiotomy ECMO support.

Support with extracorporeal membrane oxygenation for over 1 year duration as a bridge to cardiac transplantation: a case report and review of the literature

We present the case of a 13-year-old male with a complex congenital cardiac history who was supported with extracorporeal membrane oxygenation for 394 days while awaiting cardiac transplantation. The patient underwent successful cardiac transplantation after 394 days of support with veno-arterial extracorporeal membrane oxygenation and is currently alive 2 years after cardiac transplantation. We believe that this case represents the longest period of time that a patient has been supported with extracorporeal membrane oxygenation as a bridge to cardiac transplantation.We also review the literature associated with prolonged support with extracorporeal membrane oxygenation. This case report documents many of the challenges associated with prolonged support with extracorporeal membrane oxygenation, including polymicrobial bacterial and fungal infections, as well as renal dysfunction. It is possible to successfully bridge a patient to cardiac transplantation with prolonged support with extracorporeal membrane oxygenation of over 1 year; however, multidisciplinary collaboration is critical.

Outcomes of adult patients supported by extracorporeal membrane oxygenation (ECMO) following cardiopulmonary arrest. The Mayo Clinic experience

INTRODUCTION

To describe our experience in use of extracorporeal life support (ECLS) as a rescue strategy in patients following cardiopulmonary resuscitation.

METHODS

A retrospective analysis was performed for patients (n = 101) who received ECLS after cardiorespiratory arrest between May 2001 and December 2014. The primary outcome was survival to hospital discharge.

RESULTS

In this cohort median (IQR) age was 56 (37-67) years, 53 (53%) were male, and 90 (89%) were Caucasian. Ventricular tachycardia or ventricular fibrillations were the initial cardiac rhythm in 49 (48.5%) and asystole/pulseless electrical activity in 37 (36.8%). Median (IQR) time to initiation of extracorporeal support from arrest time was 72 (43-170) min. The median (IQR) duration of support was 100 (47-157) hours. Renal failure (66%) and bleeding (66%) were the two most commonly observed complications during ECLS support. The survival to hospital discharge was seen in 47 (47%) patients, and good neurologic outcome (mRs 0-3) was seen in 29%. Acidosis, lactate and continuous renal replacement therapy were independent predictors of mortality. The median (IQR) intensive care unit stay was 14 (4-28) days and hospital stay was 17 (4-35) days.

CONCLUSION

Our institutional experience with ECLS as a rescue measure following cardiac arrest is associated with improvement in mortality, and favorable neurologic status at hospital discharge.

Do platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) have a predictive value on pediatric extracorporeal membrane oxygenation (ECMO) results?

BACKGROUND

It is difficult to predict the complications and prognosis of ECMO, which is gaining widespread use in patients with pediatric surgery. Platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) are emerging inflammatory markers that can be calculated from complete blood count, which is a cheap and easily accessible laboratory analysis. The ratios between cellular elements in peripheral blood have been demonstrated to provide information on inflammation, infection, and immune response.

METHODS

Sixty-seven patients who needed ECMO application after undergoing pediatric cardiovascular surgery in our clinic, between May 2005 and April 2020, were included in this study. The age of patients varied between 4 days and 17 years with a mean of 30.59 ± 147.26 months.

RESULTS

The relationships between PLR or NLR values and various blood parameters and blood gas results were found to be statistically nonsignificant in our group of pediatric ECMO recipients. Even if the effect of PLR and NLR values on mortality and prognosis is statistically nonsignificant in patients who need ECMO after congenital heart surgery, PLR and NLR are typically elevated in the postoperative period. An increase in these values above a certain threshold may be a statistically significant indicator for the prediction of mortality.

CONCLUSIONS

There are few studies in the literature concerning PLR and NLR values in patients with pediatric heart surgery. We consider this study will make way for new studies in the future.

Veno-arterial extracorporeal membrane oxygenation: Special reference for use in 'post-cardiotomy cardiogenic shock' - A review with an Indian perspective

The ultimate goals of cardiovascular physiology are to ensure adequate end-organ perfusion to satisfy the local metabolic demand, to maintain homeostasis and achieve 'milieu intérieur'. Cardiogenic shock is a state of pump failure which results in tissue hypoperfusion and its associated complications. There are a wide variety of causes which lead to this deranged physiology, and one such important and common scenario is the post-cardiotomy state which is encountered in cardiac surgical units. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an important modality of managing post-cardiotomy cardiogenic shock with variable outcomes which would otherwise be universally fatal. VA-ECMO is considered as a double-edged sword with the advantages of luxurious perfusion while providing an avenue for the failing heart to recover, but with the problems of anticoagulation, inflammatory and adverse systemic effects. Optimal outcomes after VA-ECMO are heavily reliant on a multitude of factors and require a multi-disciplinary team to handle them. This article aims to provide an insight into the pathophysiology of VA-ECMO, cannulation techniques, commonly encountered problems, monitoring, weaning strategies and ethical considerations along with a literature review of current evidence-based practices.

Impact of CRRT in Patients with PARDS Treated with VV-ECMO

The high mortality of pediatric acute respiratory distress syndrome (PARDS) is partly related to fluid overload. Extracorporeal membrane oxygenation (ECMO) is used to treat pediatric patients with severe PARDS, but can result in acute kidney injury (AKI) and worsening fluid overload. The objective of this study was to determine whether the addition of CRRT to ECMO in patients with PARDS is associated with increased mortality. Methods: We conducted a retrospective 7-year study of patients with PARDS requiring ECMO and divided them into those requiring CRRT and those not requiring CRRT. We calculated severity of illness scores, the amount of blood products administered to both groups, and determined the impact of CRRT on mortality and morbidity. Results: We found no significant difference in severity of illness scores except the vasoactive inotropic score (VIS, 45 ± 71 vs. 139 ± 251, p = 0.042), which was significantly elevated during the initiation and the first three days of ECMO. CRRT was associated with an increase in the use of blood products and noradrenaline (p < 0.01) without changing ECMO duration, length of PICU stay or mortality. Conclusion: The addition of CRRT to ECMO is associated with a greater consumption of blood products but no increase in mortality.

Review of acute kidney injury and continuous renal replacement therapy in pediatric extracorporeal membrane oxygenation

Purpose

To review the relevant literature of acute kidney injury (AKI) and continuous renal replacement therapy (CRRT) as it relates to pediatric extracorporeal membrane oxygenation (ECMO).

Methods

Available online relevant literature.

Results

ECMO is a therapeutic modality utilized to support patients with refractory respiratory and/or cardiac failure. AKI and fluid overload (FO) are frequently observed in this patient population. There are multiple modalities that can be utilized for AKI and FO which include the following: diuretics, in-line hemofiltration, and CRRT. There are multiple considerations when using CRRT with ECMO including access, CRRT flows, hemolysis, anticoagulation, and CRRT termination.

Conclusion

While each ECMO center has its own set of equipment, experiences, and practices, it is imperative that the international ECMO community continues to work together to provide an evidence-based approach to address the morbidity and mortality associated with AKI and FO.

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.

Fluid overload and fluid removal in pediatric patients on extracorporeal membrane oxygenation requiring continuous renal replacement therapy: a multicenter retrospective cohort study

OBJECTIVE

The aim of this study was to characterize continuous renal replacement therapy (CRRT) utilization on extracorporeal membrane oxygenation (ECMO) and to determine the association of both fluid overload (FO) at CRRT initiation and fluid removal during CRRT with mortality in a large multicenter cohort.

METHODS

Retrospective chart review of all children < 18 years of age concurrently treated with ECMO and CRRT from January 1, 2007, to December 31, 2011, at six tertiary care children's hospital. Children treated with hemodialysis or peritoneal dialysis were excluded from the FO analysis.

MEASUREMENTS AND MAIN RESULTS

A total of 756 of the 1009 children supported with ECMO during the study period had complete FO data. Of these, 357 (47.2%) received either CRRT or were treated with an in-line filter and thus entered into the final analysis. Survival to ECMO decannulation was 66.4% and survival to hospital discharge was 44.3%. CRRT initiation occurred at median of 1 day (IQR 0, 2) after ECMO initiation. Median FO at CRRT initiation was 20.1% (IQR 5, 40) and was significantly lower in ECMO survivors vs. non-survivors (15.3% vs. 30.5% p = 0.005) and in hospital survivors vs. non-survivors (13.5% vs. 25.9%, p = 0.004). Median FO at CRRT discontinuation was significantly lower in ECMO survivors (23% vs. 37.6% p = 0.002) and hospital survivors vs. non-survivors (22.6% vs. 36.1%, p = 0.002). In ECMO survivors, after adjusting for pH at CRRT initiation, non-renal complications, ECMO mode, support type, center, patient age and AKI, FO at CRRT initiation (p = 0.01), and FO at CRRT discontinuation (p = 0.0002) were independently associated with duration of ECMO. In a similar multivariable analysis, FO at CRRT initiation (adjusted adds ratio [aOR] 1.09, 95% CI 1.00-1.18, p = 0.045) and at CRRT discontinuation (aOR 1.11, 95% CI 1.03-1.19, p = 0.01) were independently associated with hospital mortality.

CONCLUSIONS

In a multicenter pediatric ECMO cohort, this study demonstrates that severe FO was very common at CRRT initiation. We found an independent association between the degree of FO at CRRT initiation with adverse outcomes including mortality and increased duration of ECMO support. The results suggest that intervening prior to the development of significant FO may be a clinical therapeutic target and warrants further evaluation.

Extracorporeal Membrane Oxygenation Support After Heart Transplantation in Children-Outcomes of a Single Center Cohort

OBJECTIVES

Extracorporeal membrane oxygenation is used for postcardiotomy low cardiac output but is less established following heart transplantation. We characterized outcomes for children supported with extracorporeal membrane oxygenation after heart transplantation.

DESIGN

Single-center retrospective study.

SETTING

Large pediatric cardiac referral center.

PATIENTS

All patients who received heart transplantation and were cannulated to extracorporeal membrane oxygenation between 1995 and 2016.

INTERVENTIONS

Primary outcome measure was mortality 12 months postextracorporeal membrane oxygenation. Patient characteristics were analyzed for association with outcome according to early graft failure (extracorporeal membrane oxygenation ≤ 7 d after heart transplantation), or late graft failure.

MEASUREMENTS AND MAIN RESULTS

There were 246 heart transplants during the study period and 50 extracorporeal membrane oxygenation runs in 44 patients. Median time from transplant to extracorporeal membrane oxygenation was 1 day (range, 0-11.7 yr), with early graft failure in 28 patients (median 1, range 0-2 d) and 22 extracorporeal membrane oxygenation runs in 20 late graft failure patients (median, 0.8 yr; range, 8 d to 11.7 yr), including four patients with prior extracorporeal membrane oxygenation for early graft failure. Twenty-six patients (59%) survived to hospital discharge, and survival 12 months postextracorporeal membrane oxygenation was 24 patients (55%), lower in those with late graft failure (40% vs 67%; p 0.02). Independent risk factors for 12-month mortality were congenital heart disease, higher pulmonary vascular resistance indexed to body surface area (> 2.2 Woods U/m), and higher creatinine. Higher panel reactive antibody levels were associated with 12-month mortality in the late graft failure group only.

CONCLUSIONS

Extracorporeal membrane oxygenation can be effectively used to rescue patients with graft dysfunction after heart transplantation but is associated with high early mortality. Factors associated with mortality within 12 months include presence of congenital heart disease, renal dysfunction, elevated pulmonary vascular resistance indexed to body surface area and in those supported with extracorporeal membrane oxygenation late after heart transplantation, significant human leukocyte antigen sensitization.

Extracorporeal Membrane Oxygenation in Pediatric Pulmonary Hypertension

OBJECTIVE

To describe the epidemiology, critical care interventions, and mortality of children with pulmonary hypertension receiving extracorporeal membrane oxygenation.

DESIGN

Retrospective analysis of prospectively collected multicenter data.

SETTING

Data entered into the Extracorporeal Life Support Organization database between January 2007 and November 2018.

PATIENTS

Pediatric patients between 28 days and 18 years old with a diagnosis of pulmonary hypertension.

MEASUREMENTS AND MAIN RESULTS

Six hundred thirty-four extracorporeal membrane oxygenation runs were identified (605 patients). Extracorporeal membrane oxygenation support type was pulmonary (43.1%), cardiac (40.2%), and extracorporeal cardiopulmonary resuscitation (16.7%). The majority of cannulations were venoarterial (80.4%), and 30% had a pre-extracorporeal membrane oxygenation cardiac arrest. Mortality in patients with pulmonary hypertension was 51.3% compared with 44.8% (p = 0.001) in those without pulmonary hypertension. In univariate analyses, significant predictors of mortality included age less than 6 months and greater than 5 years; pre-extracorporeal membrane oxygenation cardiac arrest; pre-extracorporeal membrane oxygenation blood gas with pH less than 7.12, PaCO2 greater than 75, PaO2 less than 35, and arterial oxygen saturation less than 60%; extracorporeal membrane oxygenation duration greater than 280 hours; extracorporeal cardiopulmonary resuscitation; and extracorporeal membrane oxygenation complications including cardiopulmonary resuscitation, inotropic support, myocardial stun, tamponade, pulmonary hemorrhage, intracranial hemorrhage, seizures, other hemorrhage, disseminated intravascular coagulation, renal replacement therapy, mechanical/circuit problem, and metabolic acidosis. A co-diagnosis of pneumonia was associated with significantly lower odds of mortality (odds ratio, 0.5; 95% CI, 0.3-0.8). Prediction models were developed using three sets of variables: 1) pre-extracorporeal membrane oxygenation (age, absence of pneumonia, and pH < 7.12; area under the curve, 0.62); 2) extracorporeal membrane oxygenation related (extracorporeal cardiopulmonary resuscitation, any neurologic complication, pulmonary hemorrhage, renal replacement therapy, and metabolic acidosis; area under the curve, 0.72); and 3) all variables combined (area under the curve, 0.75) (p < 0.001).

CONCLUSIONS

Children with pulmonary hypertension who require extracorporeal membrane oxygenation support have a significantly greater odds of mortality compared with those without pulmonary hypertension. Risk factors for mortality include age, absence of pneumonia, pre-extracorporeal membrane oxygenation acidosis, extracorporeal cardiopulmonary resuscitation, pulmonary hemorrhage, neurologic complications, renal replacement therapy, and acidosis while on extracorporeal membrane oxygenation. Identification of those pulmonary hypertension patients requiring extracorporeal membrane oxygenation who are at even higher risk for mortality may inform clinical decision-making and improve prognostic awareness.

Use of extracorporeal membrane oxygenation in postcardiotomy pediatric patients: parameters affecting survival

AIM

We aimed to investigate the risk factors affecting survival after extracorporeal membrane oxygenation use in pediatric postcardiotomy patients.

METHODS

One hundred thirty-three consecutive patients who underwent surgery for congenital heart disease who needed extracorporeal membrane oxygenation support were retrospectively analyzed.

RESULTS

In all, 3,082 patients were operated, of which 140 patients (4.54% of the total number of operations) needed extracorporeal membrane oxygenation. Eighty (60.1%) patients were successfully weaned and 51 (38.3%) patients were discharged. Of the 50 patients discharged during the mean follow-up period of 34.8 (0-192.4) months, 6 (12%) patients died. The extracorporeal membrane oxygenation support was instituted in 29 (21.8%) patients for extracorporeal membrane oxygenation cardiopulmonary resuscitation, in 44 (33.1%) patients due to the inability to be separated from cardiopulmonary bypass, in 19 (14.3%) patients due to respiratory failure, and in 41 patients due to low cardiac output syndrome. Eighty patients (60.2%) were successfully weaned from extracorporeal membrane oxygenation support. The remaining 53 (39.8%) patients died on extracorporeal membrane oxygenation. Mortality was observed in 29 (21.8%) of the 80 patients in the successful weaning group, while the remaining 51 (38.3%) patients were discharged from the hospital. Multivariate analysis showed that double-ventricular physiology increased the rate of successful weaning (odds ratio: 3.4, 95% confidence interval lower: 1.5 and upper: 8, p = 0.004) and prolonged extracorporeal membrane oxygenation durations were a risk factor in successful weaning (odds ratio: 0.9, 95% confidence interval lower: 0.8 and upper: 0.9, p = 0.007). The parameters affecting mortality were the presence of syndrome (odds ratio: 3.8, 95% confidence interval lower: 1.0 and upper: 14.9, p = 0.05), single-ventricular physiology (odds ratio: 5.3, 95% confidence interval lower: 1.8 and upper: 15.3, p = 0.002), and the need for a second extracorporeal membrane oxygenation (odds ratio: 12.9, 95% confidence interval lower: 1.6 and upper: 104.2, p = 0.02). While 1-year survival was 15.2% and 3-year survival was 12.1% in patients with single-ventricular physiology, the respective survival rates were 43.9% and 40.8%.

CONCLUSION

Parameters affecting mortality after extracorporeal membrane oxygenation support in pediatric postcardiotomy patient group were the presence of a syndrome, multiple runs of extracorporeal membrane oxygenation, and single-ventricular physiology. Timing of extracorporeal membrane oxygenation initiation, appropriate patient selection, appropriate reintervention or reoperation for patients with correctable pathology, the use of an appropriate cannulation strategy in single-ventricle patients, management of shunt flow, and appropriate interventions to reduce the incidence of complications play key roles in improving survival.

Factors affecting the outcome of extracorporeal membrane oxygenation following paediatric cardiac surgery

BACKGROUND

Extracorporeal membrane oxygenation has been widely used after paediatric cardiac surgery due to increasing complex surgical repairs in neonates and infants having complex CHDs.

MATERIALS AND METHODS

We reviewed retrospectively the medical records of all patients with CHD requiring corrective or palliative cardiac surgery at King Abdulaziz University Hospital that needed extracorporeal membrane oxygenation support between November 2015 and November 2018.

RESULTS

The extracorporeal membrane oxygenation population was 30 patients, which represented 4% of 746 children who had cardiac surgery during this period. The patients' age range was from 1 day to 20.33 years, with a median age of 6.5 months. Median weight was 5 kg (range from 2 to 53 kg). Twenty patients were successfully decannulated (66.67%), and 12 patients (40%) were survived to hospital discharge. Patients with biventricular repair tended to have better survival rate compared with those with single ventricle palliation (55.55 versus 16.66%, p-value 0.058). During the first 24 hours of extracorporeal membrane oxygenation support, the flow rate was significantly reduced after 4 hours of extracorporeal membrane oxygenation connection in successfully decannulated patients.

CONCLUSION

Survival to hospital discharge in patients requiring extracorporeal membrane oxygenation support after paediatric cardiac surgery was better in those who underwent biventricular repair than in those who had univentricular palliation. Capillary leak on extracorporeal membrane oxygenation could be a risk of mortality in patients after paediatric cardiac surgery.

Acute Kidney Injury in Pediatric Patients on Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-analysis

Background: Acute kidney injury (AKI) is a well-established complication of extra-corporal membrane oxygenation (ECMO) in the adult population. The data in the pediatric and neonatal population is still limited. Moreover, the mortality risk of AKI among pediatric patients requiring ECMO remains unclear. Thus, this meta-analysis aims to assess the incidence of AKI, AKI requiring renal replacement therapy and AKI associated mortality in pediatric/neonatal patients requiring ECMO. Methods: A literature search was performed utilizing MEDLINE, EMBASE, and the Cochrane Database from inception through June 2019. We included studies that evaluated the incidence of AKI, severe AKI requiring renal replacement therapy (RRT) and the risk of mortality among pediatric patients on ECMO with AKI. Random-effects meta-analysis was used to calculate the pooled incidence of AKI and the odds ratios (OR) for mortality. Results: 13 studies with 3523 pediatric patients on ECMO were identified. Pooled incidence of AKI and AKI requiring RRT were 61.9% (95% confidence interval (CI): 39.0-80.4%) and 40.9% (95%CI: 31.2-51.4%), respectively. A meta-analysis limited to studies with standard AKI definitions showed a pooled estimated AKI incidence of 69.2% (95%CI: 59.7-77.3%). Compared with patients without AKI, those with AKI and AKI requiring RRT while on ECMO were associated with increased hospital mortality ORs of 1.70 (95% CI, 1.38-2.10) and 3.64 (95% CI: 2.02-6.55), respectively. Conclusions: The estimated incidence of AKI and severe AKI requiring RRT in pediatric patients receiving ECMO are high at 61.9% and 40.9%, respectively. AKI among pediatric patients on ECMO is significantly associated with reduced patient survival.

Structured review of post-cardiotomy extracorporeal membrane oxygenation: Part 2-pediatric patients

Veno-arterial extracorporeal membrane oxygenation (ECMO) is established therapy for short-term circulatory support for children with life-treating cardiorespiratory dysfunction. In children with congenital heart disease (CHD), ECMO is commonly used to support patients with post-cardiotomy shock or complications including intractable arrhythmias, cardiac arrest, and acute respiratory failure. Cannulation configurations include central, when the right atrium and aorta are utilized in patients with recent sternotomy, or peripheral, when cannulation of the neck or femoral vessels are used in non-operative patients. ECMO can be used to support any form of cardiac disease, including univentricular palliated circulation. Although veno-arterial ECMO is commonly used to support children with CHD, veno-venous ECMO has been used in selected patients with hypoxemia or ventilatory failure in the presence of good cardiac function. ECMO use and outcomes in the CHD population are mainly informed by single-center studies and reports from collated registry data. Significant knowledge gaps remain, including optimal patient selection, timing of ECMO deployment, duration of support, anti-coagulation, complications, and the impact of these factors on short- and long-term outcomes. This report, therefore, aims to present a comprehensive overview of the available literature informing patient selection, ECMO management, and in-hospital and early post-discharge outcomes in pediatric patients treated with ECMO for post-cardiotomy cardiorespiratory failure.

Outcomes of early versus delayed initiation of extracorporeal life support in cardiac surgery

Background

Extracorporeal membrane oxygenation offers temporary hemodynamic support for patients with refractory cardiogenic shock after cardiovascular surgery. However, the initiation time for such patients is controversial. Changing the initiation time might improve the outcomes. This study aimed to investigate whether early extracorporeal membrane oxygenation could improve postoperative outcomes in patients at a high risk of cardiogenic shock.

Methods

In this retrospective study, 173 patients with cardiovascular diseases at a high risk of refractory cardiogenic shock which assessed via empirical risk evaluation from 2010 to 2017 were included. After propensity matching, 36 patients, who were matched to patients initiated with extracorporeal membrane oxygenation after cardiovascular operation (delayed extracorporeal membrane oxygenation group, n = 36), were also initiated with such early in the operating room (early extracorporeal membrane oxygenation group, n = 36). The primary outcome was death. The secondary outcomes included receiving continuous renal replacement therapy, ventricular arrhythmia, and pulmonary infection.

Results

The demographic and baseline variables were similar between the matched groups. The early extracorporeal membrane oxygenation group showed lower mortality (69.44% vs 41.67%, P = 0.03), pulmonary infection morbidity (86.11% vs 55.56%, P < 0.01), and continuous renal replacement therapy rate(88.89% vs 66.67%, P = 0.04). Moreover, they showed improved cardiac index (P = 0.01) and lactate clearance (P < 0.01).

Conclusions

Extracorporeal membrane oxygenation provides effective support for cardiogenic failure refractory to medical management; early initiation improves cardiac output and promotes lactate clearance, thus increasing survival in patients with cardiogenic shock after cardiovascular surgery.

Trial registration

This is a retrospective study. It was not registered.

Blood Lactate as a Reliable Marker for Mortality of Pediatric Refractory Cardiogenic Shock Requiring Extracorporeal Membrane Oxygenation

The objective of this study is to establish reliable markers for mortality in children with refractory cardiogenic shock who underwent extracorporeal membrane oxygenation. A retrospective observational cohort study was performed at academic children's hospital for forty-three consecutive pediatric patients who required veno-arterial extracorporeal membrane oxygenation (ECMO) support with refractory cardiogenic shock from January 2011 to October 2017. 30-day mortality in this cohort was 39.5% (17/43), and successful ECMO weaning rate was 69.8%. Blood lactate was elevated before ECMO implantation and the lactate peak concentration had significant differences between survivors and non-survivors, 8.4 ± 4.3 vs 13.9 ± 6.6 mmol/L. AUC to ROC curve analysis of lactate peak was 0.745 (p < 0.05), and the best cut-off value was 14.2 mmmol/L (sensitivity: 53%, specificity: 92%). The length of lactate level > 5 mmol/L was the most significant connection to 30-day mortality. Its AUC was 0.722 (p < 0.05), and the best cut-off value was 3.3 h (sensitivity: 67%, specificity: 80%). Non-survivors had significantly higher lactate levels during 0-6 h of ECMO support, compared to survivors, which also persisted at 7-12-h, 13-24-h, and 25-48-h ECMO. However, lactate clearance at 12 h, 24 h, 48 h revealed no significant differences between survivors and non-survivors based on 30-day mortality. Lactate peak and the duration of high lactate concentration before ECMO were reliable markers for 30-day mortality of pediatric patients with refractory cardiogenic shock. Static lactate values after ECMO implantation were associated with mortality while dynamic lactate value was not. Ensuring adequate ECMO support after cannulation and early diagnostic and intervention should be implemented to normalize the lactate level.

Prognostic Risk Analyses for Postcardiotomy Extracorporeal Membrane Oxygenation in Children: A Review of Early and Intermediate Outcomes

We evaluated the morbidity and mortality of children requiring postcardiotomy extracorporeal membrane oxygenation (ECMO) to determine independent factors affecting early and intermediate outcomes. Between January 2002 and December 2015, 79 instances of ECMO after cardiac surgery in 73 children were retrospectively reviewed. Follow-up was completed in December 2016. Predictive risk analyses were employed concerning weaning of ECMO, hospital discharge, and mortality after discharge. Age and weight were 14.9 ± 25.6 months and 7.0 ± 5.3 kg, respectively. Median support time was 8.3 ± 4.4 days. Sixty-seven (85%) were successfully weaned off ECMO and 48 (61%) survived to hospital discharge. Multi-variate logistic regression analysis identified the first day to obtain negative fluid balance after initiation of support (adjusted odds ratio = 0.42), high serum lactate levels (0.97), and high total bilirubin (0.84) during support as significant independent factors associated with successful separation from ECMO. The first day of negative fluid balance (0.65) after successful decannulation was an independent risk factor for survival to hospital discharge. After hospital discharge, actuarial 1-year, 5-year, and 10-year survival rates were 94%, 78%, and 78%, respectively. Low weight increased the risk of death after hospital discharge by a multi-variate Cox hazard model. High serum lactate, high serum bilirubin, and unable to obtain early negative fluid balance during support impacted mortality of decannulation. Obtaining a late negative fluid balance in post-ECMO were independent risk factors for death after successful weaning. Low weight affected intermediate outcomes.

Neonatal Cardiac ECMO in 2019 and Beyond

Worldwide, the use of Extracorporeal Membrane Oxygenation (ECMO) for cardiac failure has been steadily increasing in the neonatal population and has become a widely accepted modality. Especially in centers caring for children with (congenital) heart disease, ECMO is now an essential part of care available for those with severe heart failure as a bridge to recovery, long term mechanical support, or transplantation. Short-term outcomes depend very much on indication. Hospital survival is ~40% for all neonatal cardiac ECMO patients combined. ECMO is being used for pre- and/or post-operative stabilization in neonates with congenital heart disease and in neonates with medical heart disease such as myocarditis, cardiomyopathy or refractory arrhythmias. ECMO use during resuscitation (ECPR) or for sepsis is summarized elsewhere in this special edition of Frontiers in Pediatrics. In this review article, we will discuss the indications for neonatal cardiac ECMO, the difficult process of patients' selection and identifying the right timing to initiate ECMO, as well as outline pros and cons for peripheral vs. central cannulation. We will present predictors of mortality and, very importantly, predictors of survival: what can be done to improve the outcomes for your patients. Furthermore, an overview of current insights regarding supportive care in neonatal cardiac ECMO is given. Additionally, we will address issues specific to neonates with single ventricle physiology on ECMO, for example cannulation strategies and the influence of shunt type (Blalock-Taussig shunt vs. "right ventricle to pulmonary artery" shunt). We will not only focus on short term outcomes, such as hospital survival, but also on the importance of long-term neuro-developmental outcomes, and we will end this review with suggestions for future research.

Factors Associated With Mortality in Children Who Successfully Wean From Extracorporeal Membrane Oxygenation

OBJECTIVES

Extracorporeal membrane oxygenation is an established therapy for cardiac and respiratory failure unresponsive to usual care. Extracorporeal membrane oxygenation mortality remains high, with ongoing risk of death even after successful decannulation. We describe occurrence and factors associated with mortality in children weaned from extracorporeal membrane oxygenation.

DESIGN

Retrospective cohort study.

SETTING

Two hundred five extracorporeal membrane oxygenation centers reporting to the Extracorporeal Life Support Organization.

SUBJECTS

Eleven thousand ninety-six patients, less than 18 years, supported with extracorporeal membrane oxygenation during 2007-2013, who achieved organ recovery before decannulation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Primary outcome was hospital mortality less than or equal to 30 days post extracorporeal membrane oxygenation decannulation. Among 11,096 patients, indication for extracorporeal membrane oxygenation cannulation was respiratory (6,206; 56%), cardiac (3,663; 33%), or cardiac arrest (extracorporeal cardiopulmonary resuscitation, 1,227; 11%); the majority were supported with venoarterial extracorporeal membrane oxygenation at some stage in their course (8,576 patients; 77%). Mortality was 13%. Factors associated with mortality included younger age (all < 1 yr categories compared with older, p < 0.05), lower weight among neonates (≤ 3 vs > 3 kg; p < 0.001), mode of extracorporeal membrane oxygenation support (venoarterial extracorporeal membrane oxygenation compared with venovenous extracorporeal membrane oxygenation, p < 0.001), longer admission to extracorporeal membrane oxygenation cannulation time (≥ 28 vs < 28 hr; p < 0.001), cardiac and extracorporeal cardiopulmonary resuscitation compared with respiratory extracorporeal membrane oxygenation (both p < 0.001), extracorporeal membrane oxygenation duration greater than or equal to 135 hours (p < 0.001), preextracorporeal membrane oxygenation hypoxemia (PO2 ≤ 43 vs > 43 mm Hg; p < 0.001), preextracorporeal membrane oxygenation acidemia (p < 0.001), and extracorporeal membrane oxygenation complications, particularly cerebral or renal (both p < 0.001).

CONCLUSIONS

Despite extracorporeal membrane oxygenation decannulation for organ recovery, 13% of patients die in hospital. Mortality is associated with patient factors, preextracorporeal membrane oxygenation illness severity, and extracorporeal membrane oxygenation management. Evidence-based strategies to optimize readiness for extracorporeal membrane oxygenation decannulation and postextracorporeal membrane oxygenation decannulation care are needed.

Useful References in Pediatric Cardiac Intensive Care: The 2017 Update

OBJECTIVES

Pediatric cardiac intensive care continues to evolve, with rapid advances in knowledge and improvement in clinical outcomes. In the past, the Board of Directors of the Pediatric Cardiac Intensive Care Society created and subsequently updated a list of sentinel references focused on the care of critically ill children with congenital and acquired heart disease. The objective of this article is to provide clinicians with a compilation and brief summary of updated and useful references that have been published since 2012.

DATA SELECTION

Pediatric Cardiac Intensive Care Society members were solicited via a survey sent out between March 20, 2017, and April 28, 2017, to provide important references that have impacted clinical care. The survey was sent to approximately 523 members. Responses were received from 45 members, of which some included multiple references.

DATA EXTRACTION

Following review of the list of references, and removing editorials, references were compiled by the first and last author. The final list was submitted to members of the society's Research Briefs Committee, who ranked each publication.

DATA SYNTHESIS

Rankings were compiled and the references with the highest scores included. Research Briefs Committee members ranked the articles from 1 to 3, with one being highly relevant and should be included and 3 being less important and should be excluded. Averages were computed, and the top articles included in this article. The first (K.C.U.) and last author (K.M.G.) reviewed and developed summaries of each article.

CONCLUSIONS

This article contains a compilation of useful references for the critical care of children with congenital and acquired heart disease published in the last 5 years. In conjunction with the prior version of this update in 2012, this article may be used as an educational reference in pediatric cardiac intensive care.

Association of Pediatric Cardiac Surgical Volume and Mortality After Cardiac ECMO

Centers with higher surgical and extracorporeal membrane oxygenation (ECMO) volumes have improved survival for children undergoing pediatric cardiac surgery and ECMO, respectively. We examined the relationship between both cardiac surgical and cardiac ECMO volumes, with survival. Using data from the Pediatric Health Information System, we reviewed patients who underwent ECMO during the hospitalization for cardiac surgery or heart transplantation from January 2003 to June 2014. Among 106,967 patients in 43 centers undergoing a Risk Adjustment for Congenital Heart Surgery-1 1-6 procedure (n = 104,951) or cardiac transplantation (n = 2,016), 2.9% (n = 3,069) underwent ECMO support. Centers were categorized into volume quartiles based on annual ECMO and cardiac surgical volumes. Multivariable logistic regression models controlling for clustering by center and adjusting for factors associated with mortality were constructed. Although mortality was lower in ECMO centers that performed ≥7 ECMO runs (odds ratio [OR]: 0.44, 95% confidence interval [CI]: 0.22-0.88)] and centers performing ≥158 cardiac surgical cases (OR: 0.37, 95% CI: 0.22-0.63), surgical volume was more strongly associated with ECMO mortality. Centers with higher cardiac surgical volume had fewer ECMO complications. Cardiac surgical volume, compared with ECMO volume, is more strongly associated with cardiac ECMO survival.

Ventricular assist device use in single ventricle congenital heart disease

As VAD have become an effective therapy for end-stage heart failure, their application in congenital heart disease has increased. Single ventricle congenital heart disease introduces unique physiologic challenges for VAD use. However, with regard to the mixed clinical results presented within this review, we suggest that patient selection, timing of implant, and center experience are all important contributors to outcome. This review focuses on the published experience of VAD use in single ventricle patients and details physiologic challenges and novel approaches in this growing pediatric and adult population.

When CRRT on ECMO Is Not Enough for Potassium Clearance: A Case Report

Background:

Continuous renal replacement therapy (CRRT) is an excellent method used to remove fluid and solutes. It may also reduce the systemic inflammatory response for patients on extracorporeal membrane oxygenation (ECMO) support. The objective of this report is to describe a case where CRRT in combination with ECMO was insufficient to control hyperkalemia.

Methods:

We report the case of an adolescent patient with refractory symptomatic hyperkalemia due to substantial rhabdomyolysis in which CRRT insufficiently cleared the patient’s excess potassium.

Results:

Intermittent hemodialysis (IHD) was added and proved successful. The patient was weaned off ECMO, CRRT, and IHD, and his cardiac and renal function eventually normalized.

Conclusions:

Two important lessons can be learned from this case report: (1) If CRRT is insufficient in achieving a desirable potassium balance, additional IHD should be considered and (2) separate IHD access should be considered to improve efficacy.

Experience with Mechanical Circulatory Support for Medically Intractable Low Cardiac Output in a Pediatric Intensive Care Unit

Background and Objectives

Mechanical circulatory support with extracorporeal membrane oxygenation (ECMO) and ventricular assist device has always been the optimal choice for treating the majority of medically intractable low cardiac output case. We retrospectively investigated our institution's outcomes and variables associated with a high risk of mortality.

Subjects and Methods

From 1999 to 2014, 86 patients who were of pediatric age or had grown-up congenital heart disease underwent mechanical circulatory support for medically intractable low cardiac output in our pediatric intensive care unit. Of these, 9 grown-up congenital heart disease patients were over 18 years of age, and the median age of the subject group was 5.82 years (range: 1 day to 41.6 years). A review of all demographic, clinical, and surgical data and survival analysis were performed.

Results

A total of 45 (52.3%) patients were successfully weaned from the mechanical assist device, and 25 (29.1%) survivors were able to be discharged. There was no significant difference in results between patients over 18 years and under 18 years of age. Risk factors for mortality were younger age (<30 days), functional single ventricle anatomy, support after cardiac operations, longer support duration, and deteriorated pre-ECMO status (severe metabolic acidosis and increased levels of lactate, creatinine, bilirubin, or liver enzyme). The survival rate has improved since 2010 (from 25% before 2010 to 35% after 2010), when we introduced an upgraded oxygenator, activated heart transplantation, and also began to apply ECMO before the end-stage of cardiac dysfunction, even though we could not reveal significant correlations between survival rate and changed strategies associated with ECMO.

Conclusion

Mechanical circulatory support has played a critical role and has had a dramatic effect on survival in patients with medically intractable heart failure, particularly in recent years. Meticulous monitoring of acid-base status, laboratory findings, and early and liberal applications are recommended to improve outcomes without critical complication rates, particularly in neonates with single ventricle physiology.

Extracorporeal Life Support: Four Decades and Counting

Extracorporeal membrane oxygenation (ECMO) or extracorporeal life support (ECLS) is a form of heart lung bypass that is used to support neonates, pediatrics, and adult patients with cardiorespiratory failure for days or weeks till organ recovery or transplantation. Venoarterial (VA) and venovenous (VV) ECLS are the most common modes of support. ECLS circuit components and monitoring have been evolving over the last 40 years. The technology is safer, simpler, and more durable with fewer complications. The use of neonatal respiratory ECLS use has been declining over the last two decades, while adult respiratory ECLS is growing especially since the H1N1 influenza pandemic in 2009. This review provides an overview of ECLS evolution over the last four decades, its use in neonatal, pediatric and adults, description of basic principles, circuit components, complications, and outcomes as well as a quick look into the future.

Laboratory and clinical predictors of 30-day survival for patients on Extracorporeal Membrane Oxygenation (ECMO): 8-Year experience at Albert Einstein College of Medicine, Montefiore Medical Center

PURPOSE

Survival of patients on ECMO has remained stable in every population. Laboratory values predictors of survival are required to improve patient care.

MATERIALS AND METHODS

Clinical Looking Glass software was used to assess Electronic Medical Records (EMRs) of patients at Albert Einstein College of Medicine, Montefiore Medical Center (2007-2014).

RESULTS

Our population comprises of 166 adults and was divided in survivors and non-survivors, within 30days. Indications for ECMO were cardiac (65%), respiratory (25%) and infectious diseases (<10%). Eighty six patients (51.8%) survived the procedure. Gender, body weight, ejection fraction, diastolic blood pressure, and socio-economic status did not differ among survivors and non-survivors. In contrast, younger patients (45yo vs 55yo, p=0.0001) and higher systolic blood pressure (115mmHg vs 103mmHg, p=0.025) have favorable outcome. Univariate analysis shows that pre-cannulation values for creatinine (p=0.0003), chloride (p=0.009), bicarbonate (p=0.015) and pH (p=0.03) have prognostic value. Post-cannulation aPTT, pH, platelet and lymphocyte counts also have discriminative power. Notably, multiple logistic regressions for Multivariate Analysis identified chloride (OR 1.07; 95% CI 1.02-1.13; p=0.004), pH (OR 3.35; 95% CI 1.89-5.9; p<0.0001) and aPTT (OR 0.98; 95% CI 0.976-0.998; p=0.024) as independent risk factors for 30-day mortality. These results imply that pre-existing renal conditions and hemostatic dysregulation contribute to poor outcome. Finally, patients on VV-ECMO have increase odds of survival (OR 1.88; 95% CI 1.06-3.34; p=0.029).

CONCLUSIONS

Laboratory markers identified herein may guide the management of patients on ECMO.

Post-cardiotomy Rescue Extracorporeal Cardiopulmonary Resuscitation in Neonates with Single Ventricle After Intractable Cardiac Arrest: Attrition After Hospital Discharge and Predictors of Outcome

Extracorporeal cardiopulmonary resuscitation (ECPR) in children with cardiac arrest refractory to conventional cardiopulmonary resuscitation (CPR) has been reported with encouraging results. We reviewed outcomes of neonates with functional single ventricle (FSV) surviving post-cardiotomy ECPR after hospital discharge. Fifty-eight patients who required post-cardiotomy extracorporeal membrane oxygenation (ECMO) since the introduction of our ECPR protocol (January 2007-December 2011) were identified. Forty-one were neonates. Survival analysis was conducted. Of 41 neonates receiving post-cardiotomy ECMO, 32 had FSV. Twenty-one had ECPR. Fourteen underwent Norwood operation (NO) for hypoplastic left heart syndrome (HLHS). Seven had non-HLHS FSV. Four (of 7) underwent modified NO/DKS with systemic-to-pulmonary shunt (SPS), 2 SPS only and 1 SPS with anomalous pulmonary venous connection repair. Mean age was 6.8 ± 2.1 days. ECMO median duration was 7 days [interquartile range (IQR_25-75: 4-18)]. Survival to ECMO discontinuation was 72% (15 of 21 patients) and at hospital discharge 62% (13 of 21 patients). The most common cause of late attrition was cardiac. At last follow-up (median: 22 months; IQR_25-75: 3-36), 47% of patients were alive. Duration of ECMO and failure of lactate clearance within 24 h from ECMO deployment determined late survival after hospital discharge (p < 0.05). Rescue post-cardiotomy ECMO support in neonates with FSV carries significant late attrition. ECMO duration and failure in lactate clearance after deployment are associated with unfavorable outcome. Emphasis on CPR quality, refinement of management directives early during ECMO and aggressive early identification of patients requiring heart transplantation might improve late survival.

Is Administration of Nitric Oxide During Extracorporeal Membrane Oxygenation Associated With Improved Patient Survival?

OBJECTIVE

To evaluate the outcomes associated with the use of inhaled nitric oxide during extracorporeal membrane oxygenation.

DESIGN

Post hoc analysis of data from an existing administrative national database, Pediatric Health Information system (2004-2014). Multivariable logistic regression models were fitted to study the effect of inhaled nitric oxide during extracorporeal membrane oxygenation on study outcomes.

SETTING

Forty-two children's hospitals across the United States.

PATIENTS

Patients in the age group from 1 day through 18 years admitted to an ICU who received extracorporeal membrane oxygenation during their hospital stay were included.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

In total, 6,419 patients qualified for inclusion. Of these, inhaled nitric oxide was used among 3,629 patients during extracorporeal membrane oxygenation run. Approximately one half of the study patients received inhaled nitric oxide at extracorporeal membrane oxygenation initiation. The proportion of patients receiving inhaled nitric oxide during extracorporeal membrane oxygenation decreased with increasing duration of extracorporeal membrane oxygenation. After adjusting for patient characteristics and center variables, use of inhaled nitric oxide was not associated with any survival benefit. However, higher proportion of patients receiving inhaled nitric oxide were associated with prolonged hospital length of stay and prolonged duration of extracorporeal membrane oxygenation. In adjusted models, the hospital charges were higher in the inhaled nitric oxide group. The median hospital costs among patients receiving inhaled nitric oxide were higher by $39,732 (95% CI, $31,074-48,390) as compared to the patients who did not receive inhaled nitric oxide, after adjusting for patient (including hospital length of stay) and center level variables. As the duration of inhaled nitric oxide therapy increased, proportion of patients with prolonged duration of extracorporeal membrane oxygenation and prolonged hospital length of stay increased.

CONCLUSIONS

This large observational analysis of use of nitric oxide during extracorporeal membrane oxygenation calls into question the benefits of inhaled nitric oxide among patients receiving extracorporeal membrane oxygenation for pulmonary or cardiac failure. Given our inability to determine type of extracorporeal membrane oxygenation and control for severity of illness, these findings should be interpreted as exploratory.

Factors Associated With Mortality in Neonates Requiring Extracorporeal Membrane Oxygenation for Cardiac Indications: Analysis of the Extracorporeal Life Support Organization Registry Data

OBJECTIVES

Survival among neonates supported with extracorporeal membrane oxygenation for cardiac indications is 39%. Previous single-center studies have identified factors associated with mortality, but a comprehensive multivariate analysis is not available for this population. Understanding factors associated with mortality may help design treatment strategies, determine optimal timing for cannulation, and inform patient selection. This study identifies factors associated with mortality in neonates supported with extracorporeal membrane oxygenation for cardiac indications.

DESIGN

Retrospective cohort study.

SETTING

Two hundred and thirty U.S. and international centers reporting extracorporeal membrane oxygenation data to the Extracorporeal Life Support Organization.

SUBJECTS

Four thousand and four seventy one neonates with congenital and acquired cardiac disease supported with extracorporeal membrane oxygenation for cardiac indications during 2001-2011.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

The primary outcome measure was mortality prior to hospital discharge. Overall hospital mortality was 59%. Demographic and preextracorporeal membrane oxygenation factors associated with mortality were evaluated in a multivariable model. Factors associated with death prior to hospital discharge included lower body weight, earlier era, single ventricle physiology, lower preextracorporeal membrane oxygenation arterial pH, and longer time from intubation to extracorporeal membrane oxygenation cannulation. Lower pH was associated with increased mortality regardless of cardiac diagnosis and surgical complexity. The majority of survivors separated from extracorporeal membrane oxygenation less than 8 days after extracorporeal membrane oxygenation deployment.

CONCLUSIONS

Mortality for neonates supported with extracorporeal membrane oxygenation for cardiac indications is high. Severity of preextracorporeal membrane oxygenation acidosis was independently associated with increased risk of mortality. Earlier initiation of extracorporeal membrane oxygenation may reduce the degree and duration of acidosis and may improve survival. Further studies are needed to determine optimal timing of cannulation in this population.

Clinical Research in Acute Fatal Illness

Clinical research to evaluate the effectiveness of life support systems in acute fatal illness has unique problems of logistics, ethics, and consent. There have been 10 prospective comparative trials of extracorporeal membrane oxygenation in acute fatal respiratory failure, utilizing different study designs. The trial designs were prospective controlled randomized, prospective adaptive randomized, sequential, and matched pairs. The trials were reviewed with regard to logistics, ethics, consent, statistical methods, economics, and impact. The matched pairs method is the best study design for evaluation of life support systems in acute fatal illness.

Extracorporeal Life Support in Pediatric and Neonatal Critical Care: A Review

Extracorporeal life support (ECLS) is a modified form of cardiopulmonary bypass used to provide prolonged tissue oxygen delivery in patients with respiratory and/or cardiac failure. The first large-scale success of ECLS was achieved in the management of term newborns with respiratory failure. ECLS has become an accepted therapeutic modality for neonates, children, and adults who have failed conventional therapy and in whom cardiac and/or respiratory insufficiency is potentially reversible. The use of ECLS allows one to reduce other cardiopulmonary supports and apply a gentle ventilation strategy in a population of severely compromised critical care patients. ECLS has now been employed in more than 26,000 neonatal and pediatric patients with an overall survival rate of 68%. ECLS has evolved significantly over 25 years of clinical practice; patient selection for this complex and highly invasive therapy, as well as how ECLS is employed in different patient groups, is constantly changing. Generally, ECLS is used more liberally now than in the past. The number of patients requiring this support, however, is declining yearly, and those patients who receive ECLS compose a more severe subset of an intensive care population. This review provides an overview of the development of ECLS and the equipment and techniques employed. The use of ECLS for neonatal respiratory failure, pediatric respiratory failure, and cardiac support are outlined. Management of the ECLS patient is discussed in detail, and outcome of these patients is reviewed. Finally, current trends and future implications of ECLS in neonatal and pediatric critical care are addressed.

Is it possible to predict outcome in cardiac ECMO? Analysis of preoperative risk factors

Background. Serious heart failure may be treated with extracorporeal membrane oxygenation (ECMO) when other treatment fails. The aim of the present study was to analyse preoperative risk factors of early mortality in patients treated with veno-arterial (VA)-ECMO. Methods. We studied a total of 18 possible risk factors in 80 patients with severe cardiac insufficiency treated with VA-ECMO. All consecutive cases treated at our institution between Sept.1990 and May 2006 were included. Univariate analysis and multiple logistic regression analysis were performed on 16 risk factors. The endpoint was early mortality (any death within 30 days of ECMO treatment). Results. Thirty patients (37.5%) died within 30 days. Age, gender, cause of cardiac failure, pre-ECMO treatment (ventilator, NO, IABP) did not significantly influence early mortality. A higher SvO2 was associated with survival and remained significant in the multivariate analysis. Conclusion. Treatment with VA-ECMO in patients with severe cardiac failure may save lives. It is, however, difficult to predict outcome. In this study, only SvO2 values prior to ECMO were positively associated with survival. Perfusion (2007) 22, 225—229.