Indication for initiation of mechanical circulatory support impacts survival of infants with shunted single-ventricle circulation supported with extracorporeal membrane oxygenation

Short-Term Outcomes, Functional Status, and Risk Factors for Requiring Extracorporeal Life Support After Norwood Operation: A Single-Center Retrospective Study

Patients requiring extracorporeal life support (ECLS) post-Norwood operation constitute an extremely high-risk group. We retrospectively described short-term outcomes, functional status, and assessed risk factors for requiring ECLS post-Norwood operation between January 2010 and December 2020 in a high-volume center. During the study period, 269 patients underwent a Norwood procedure of which 65 (24%) required ECLS. Of the 65 patients, 27 (41.5%) survived to hospital discharge. Mean functional status scale (FSS) score at discharge increased from 6.0 on admission to 8.48 (p < 0.0001). This change was primary in feeding (p < 0.0001) and respiratory domains (p = 0.017). Seven survivors (26%) developed new morbidity, and two (7%) developed unfavorable functional outcomes. In the regression analysis, we showed that patients with moderate-severe univentricular dysfunction on pre-Norwood transthoracic echocardiogram (odds ratio [OR] = 6.97), modified Blalock Taussig Thomas (m-BTT) shunt as source of pulmonary blood flow (OR = 2.65), moderate-severe atrioventricular valve regurgitation on transesophageal echocardiogram (OR = 8.50), longer cardiopulmonary bypass time (OR = 1.16), longer circulatory arrest time (OR = 1.20), and delayed sternal closure (OR = 3.86), had higher odds of requiring ECLS (p < 0.05). Careful identification of these risk factors is imperative to improve the care of this high-risk cohort and improve overall outcomes.

Early outcomes after post-cardiotomy extracorporeal membrane oxygenation in paediatric patients: a contemporary, binational cohort study

OBJECTIVES

The aim of this study was to assess the early outcomes and risk factors of paediatric patients requiring extracorporeal membrane oxygenation after cardiac surgery (post-cardiotomy).

METHODS

Retrospective binational cohort study from the Australia and New Zealand Congenital Outcomes Registry for Surgery database. All patients younger than 18 years of age who underwent a paediatric cardiac surgical procedure from 1 January 2013 to 31 December 2021 and required post-cardiotomy extracorporeal membrane oxygenation (PC-ECMO) in the same hospital admission were included in the study.

RESULTS

Of the 12 290 patients included in the study, 376 patients required post-cardiotomy ECMO (3%). Amongst these patients, hospital mortality was 35.6% and two-thirds of patients experienced a major complication. Hypoplastic left heart syndrome was the most common diagnosis (17%). The Norwood procedure and modified Blalock-Taussig shunts had the highest incidence of requiring PC-ECMO (odds ratio of 10 and 6.8 respectively). Predictors of hospital mortality after PC-ECMO included single-ventricle physiology, intracranial haemorrhage and chylothorax.

CONCLUSIONS

In the current era, one-third of patients who required PC-ECMO after paediatric cardiac surgery in Australia and New Zealand did not survive to hospital discharge. The Norwood procedure and isolated modified Blalock-Taussig shunt had the highest incidence of requiring PC-ECMO. Patients undergoing the Norwood procedure had the highest mortality (48%). Two-thirds of patients on PC-ECMO developed a major complication.

Outcome after extracorporeal membrane oxygenation therapy in Norwood patients before the bidirectional Glenn operation

OBJECTIVES

Patients after the Norwood procedure are prone to postoperative instability. Extracorporeal membrane oxygenation (ECMO) can help to overcome short-term organ failure. This retrospective single-centre study examines ECMO weaning, hospital discharge and long-term survival after ECMO therapy between Norwood and bidirectional Glenn palliation as well as risk factors for mortality.

METHODS

In our institution, over 450 Norwood procedures have been performed. Since the introduction of ECMO therapy, 306 Norwood operations took place between 2007 and 2022, involving ECMO in 59 cases before bidirectional Glenn. In 48.3% of cases, ECMO was initiated intraoperatively post-Norwood. Patient outcomes were tracked and mortality risk factors were analysed using uni- and multivariable testing.

RESULTS

ECMO therapy after Norwood (median duration: 5 days; range 0-17 days) saw 31.0% installed under CPR. Weaning was achieved in 46 children (78.0%), with 55.9% discharged home after a median of 45 (36-66) days. Late death occurred in 3 patients after 27, 234 and 1541 days. Currently, 30 children are in a median 4.8 year (3.4-7.7) follow-up. At the time of inquiry, 1 patient awaits bidirectional Glenn, 6 are at stage II palliation, Fontan was completed in 22 and 1 was lost to follow-up post-Norwood. Risk factor analysis revealed dialysis (P < 0.001), cerebral lesions (P = 0.026), longer ECMO duration (P = 0.002), cardiac indication and lower body weight (P = 0.038) as mortality-increasing factors. The 10-year mortality probability after ECMO therapy was 48.5% (95% CI 36.5-62.9%).

CONCLUSIONS

ECMO therapy in critically ill patients after the Norwood operation may significantly improve survival of a patient cohort otherwise forfeited and give the opportunity for successful future-stage operations.

Extracorporeal Membrane Oxygenation Then and Now; Broadening Indications and Availability

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

Timing of reintervention influences survival and resource utilization following first-stage palliation of single ventricle heart disease

OBJECTIVE

Outcomes after first-stage palliation of single-ventricle heart disease are influenced by many factors, including the presence of residual lesions requiring reintervention. However, there is a dearth of information regarding the optimal timing of reintervention. We assessed if earlier reintervention would be favorably associated with in-hospital outcomes among patients requiring unplanned reinterventions after the Norwood operation.

METHODS

This was a single-center, retrospective review of all patients who underwent the Norwood procedure from January 1997 to November 2017 and required a predischarge unplanned surgical or transcatheter reintervention on 1 or more subcomponent areas repaired at the index operation. Outcomes of interest included in-hospital mortality or transplant, postoperative hospital length of stay, and inpatient cost. Associations between timing of reintervention and outcomes were assessed using logistic regression (mortality or transplant) or generalized linear models (postoperative hospital length of stay and cost), adjusting for baseline patient-related and procedural factors.

RESULTS

Of 500 patients who underwent the Norwood operation, 92 (18.4%) required an unplanned reintervention. Median time to reintervention was 12 days (interquartile range, 5-35 days). There were 31 (33.7%) deaths or transplants, median postoperative hospital length of stay was 49 days (interquartile range, 32-87 days), and median cost was $328,000 (interquartile range, $204,000-$464,000). On multivariable analysis, each 5-day increase in time to reintervention increased the odds of mortality or transplant by 20% (odds ratio, 1.2; 95% confidence interval, 1.1-1.3; P = .004). Longer time to reintervention was also significantly associated with greater postoperative hospital length of stay (P < .001) and higher cost (P < .001).

CONCLUSIONS

For patients requiring predischarge unplanned reinterventions after the Norwood operation, earlier reintervention is associated with improved in-hospital transplant-free survival and resource use.

Outcomes of Extracorporeal Membrane Oxygenation in Patients After Repair of Congenital Heart Defects

Extracorporeal membrane oxygenation (ECMO) is widely used after congenital heart surgery. The purpose of this study is to analyze the factors influencing mortality and morbidity in patients who require ECMO support after congenital cardiac surgery. All 109 patients (5.8% of total cases) who underwent ECMO support after congenital heart surgery between January 2014 and 2021 were included in this single-center study. The mean age was 10.13 ± 20.55 months, and the mean weight was 6.41 ± 6.79 kg. 87 (79.8%) of the patients were under 1 year of age. A total of 54 patients (49.5%) were weaned successfully from ECMO support, and 27 of them (24.8%) were discharged. The childhood age group had the best outcomes. Seventy-seven percent of the children were weaned successfully, and 50% were discharged. 69 patients (63.3%) had biventricular physiology; weaning and survival outcomes were better than single ventricle patients (P-value 0.002 and < 0.001, respectively). Low cardiac output (n = 49; 44.9%) as an ECMO indication had better outcomes than extracorporeal cardiopulmonary resuscitation (n = 31; 28.4%) (P = 0.05). Most of the patients had ≥ 4 Modified Aristotle Comprehensive Complexity (MACC) levels, and higher MACC levels were associated with a higher mortality rate. The most common procedure was the Norwood operation (16.5%), with the worst outcome (5.5% survival). Bleeding and renal complications were the most common complications affecting outcomes. Results were more satisfactory in patients with biventricular repair, childhood, and lower MACC levels. Early initiation of ECMO in borderline patients without experiencing cardiac arrest or multiorgan failure may improve outcomes.

Impact of Intraoperative Residual Lesions and Timing of Extracorporeal Membrane Oxygenation on Outcomes Following First-Stage Palliation of Single Ventricle Heart Disease

BACKGROUND

Data regarding the influence of intraoperative residual lesions on extracorporeal membrane oxygenation (ECMO) following the Norwood procedure are limited. Moreover, the significance of postoperative ECMO timing on in-hospital outcomes remains incompletely characterized.

METHODS

This was a single-center, retrospective review of consecutive patients who underwent the Norwood operation from January 1997 to November 2017. Patients with at least minor residual lesions based on the intraoperative postcardiopulmonary bypass echocardiogram were identified. The association between residual lesions and postoperative ECMO was assessed with logistic regression, adjusting for age, weight, prematurity, various preoperative system-specific and procedural risk factors, shunt type, and era. Among patients receiving ECMO, associations between late ECMO (≥3 days post-Norwood) and in-hospital mortality or transplant, postoperative hospital length-of-stay, and cost of hospitalization were evaluated using logistic regression or generalized linear models with a gamma distribution and logarithmic link.

RESULTS

Among 500 patients, 78 (15.6%) received ECMO postoperatively. On multivariable analysis, the presence of at least minor residual lesions (odds ratio, 4.4; 95% CI, 2.1-9.3; P < .001) was associated with postoperative ECMO. In the ECMO subpopulation, there were 44 (56.4%) deaths or transplants. Late ECMO was associated with increased risk of in-hospital mortality or transplant (adjusted odds ratio, 6.2; 95% CI, 1.5-26.0), longer postoperative hospital length of stay (regression coefficient, 0.7; 95% CI, 0.3-1.1), and greater cost (regression coefficient, 0.6; 95%, CI 0.4-0.7), versus early ECMO (all P values < .05).

CONCLUSIONS

The presence of even minor intraoperative residua significantly increases the risk of ECMO following the Norwood operation. Among patients receiving ECMO postoperatively, early institution of ECMO is associated with lower mortality and resource utilization.

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.

Extracorporeal Membrane Oxygenation After Norwood Surgery in Patients With Hypoplastic Left Heart Syndrome: A Retrospective Single-Center Cohort Study From Brazil

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is increasingly being used to support patients after the repair of congenital heart disease.

OBJECTIVE

We report our experience with patients with a single functional ventricle who were supported by ECMO after the Norwood procedure, reviewing the outcomes and identifying risk factors for mortality in these patients.

METHODS

In this single-center retrospective cohort study, we enrolled 33 patients with hypoplastic left heart syndrome (HLHS) who received ECMO support after the Norwood procedure between January 2015 and December 2019. The independent variables evaluated in this study were demographic, anatomical, and those directly related to ECMO support (ECMO indication, local of initiation, time under support, and urinary output while on ECMO). The dependent variable was survival. A p < 0.05 was considered statistically significant.

RESULTS

The ECMO support was applied in 33 patients in a group of 120 patients submitted to Norwood procedure (28%). Aortic atresia was present in 72.7% of patients and mitral atresia in 51.5%. For 15% of patients, ECMO was initiated in the operating room; for all other patients, ECMO was initiated in the intensive care unit. The indications for ECMO in the cardiac intensive care unit were cardiac arrest in 22 (79%) of patients, low cardiac output state in 10 (18%), and arrhythmia in 1 patient (3%). The median time under support was 5 (2-25) days. The median follow-up time was 59 (4-150) days. Global survival to Norwood procedure was 90.9% during the 30-day follow-up, being 33.3% for those submitted to ECMO. Longer ECMO support (p = 0.004) was associated with a higher risk of death in the group submitted to ECMO.

CONCLUSIONS

The mortality of patients with HLHS who received ECMO support after stage 1 palliation was high. Patients with low urine output were related to worse survival rates, and longer periods under ECMO support (more than 9 days of ECMO) were associated with 100% mortality. Earlier ECMO initiation before multiorgan damage may improve results.

A Review of Physiologic Considerations and Challenges in Pediatric Patients With Failing Single- Ventricle Physiology Undergoing Ventricular Assist Device Placement

Advances in surgical techniques and outpatient cardiac care have led to a growing population of pediatric patients surviving well into adulthood with previous single-ventricle palliation. Continued improvement in survival has resulted in subsequent increases in the number of patients with single-ventricle physiology listed for heart transplantations. Some of these patients require mechanical circulatory support as a bridge to transplantation, although establishing successful mechanical circulatory support in these complex patients remains challenging. Only limited published data exist describing the perioperative anesthetic management and key considerations dedicated to patients with failing single-ventricle physiology presenting for ventricular assist devices. This clinical review aims to provide a focused evaluation of the vital perioperative considerations encountered in this novel population.

Use of ECMO for Cardiogenic Shock in Pediatric Population

In children with severe advanced heart failure where medical management has failed, mechanical circulatory support in the form of veno-arterial extracorporeal membrane oxygenation (VA ECMO) or ventricular assist device represents life-sustaining therapy. This review provides an overview of VA ECMO used for cardiovascular support including medical and surgical heart disease. Indications, contraindications, and outcomes of VA ECMO in the pediatric population are discussed.VA ECMO provides biventricular and respiratory support and can be deployed in rapid fashion to rescue patient with failing physiology. There have been advances in conduct and technologic aspects of VA ECMO, but survival outcomes have not improved. Stringent selection and optimal timing of deployment are critical to improve mortality and morbidity of the patients supported with VA ECMO.

Characterization of Extracorporeal Membrane Oxygenation Support for Single Ventricle Patients

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) can provide crucial support for single ventricle (SV) patients at various stages of palliation. However, characterization of the utilization and outcomes of ECMO in these unique patients remains incompletely studied.

METHODS

We performed a single-center retrospective review of SV patients between 2010 and 2017 who underwent ECMO cannulation with primary end point of survival to discharge and secondary end point of survival to decannulation or orthotopic heart transplantation (OHT). Multivariate analysis was performed for factors predictive of survival to discharge and survival to decannulation.

RESULTS

Forty SV patients with a median age of one month (range: 3 days to 15 years) received ECMO support. The incidence of ECMO was 14% for stage I, 3% for stage II, and 4% for stage III. Twenty-seven (68%) patients survived to decannulation, and 21 (53%) patients survived to discharge, with seven survivors to discharge undergoing OHT. Complications included infection (40%), bleeding (40%), thrombosis (33%), and radiographic stroke (45%). Factors associated with survival to decannulation included pre-ECMO lactate (hazard ratio [HR]: 0.61, 95% confidence interval [CI]: 0.41-0.90, P = .013) and post-ECMO bicarbonate (HR: 1.24, 95% CI: 1.0-1.5, P = .018). Factors associated with survival to discharge included central cannulation (HR: 40.0, 95% CI: 3.1-500.0, P = .005) and lack of thrombotic complications (HR: 28.7, 95% CI: 2.1-382.9, P = .011).

CONCLUSIONS

Extracorporeal membrane oxygenation can be useful to rescue SV patients with approximately half surviving to discharge, although complications are frequent. Early recognition of the role of heart transplant is imperative. Further study is required to identify areas for improvement in this population.

Use of Extracorporeal Membrane Oxygenation After Congenital Heart Disease Repair: A Systematic Review and Meta-Analysis

Introduction: Extracorporeal membrane oxygenation (ECMO) has been widely used to treat cardiopulmonary failure in patients with congenital heart defects (CHD) postoperatively. A meta-analysis is performed for outcomes of postoperative CHD patients on ECMO.

Methods: Electronic databases, including PubMed, EMbase, and Cochrane Library CENTRAL were searched systematically from January 1990 to June 2020 for literature which reported the outcomes of postoperative CHD cases on ECMO. The scope of this search was restricted to articles published in English.

Results: Forty-three studies were included in this study, involving 3,585 subjects. Postoperative ventricular failure with low cardiac output was the most common indication of ECMO initiation. The pooled estimated incidence of in-hospital mortality was 56.8% (95% CI, 52.5–61.0%). Bleeding was the most common complication with ECMO with an incidence of 47.1% (95% CI, 38.5–55.8%). Multivariate meta-regression analysis revealed that single ventricular physiology (coefficient 0.213, 95% CI 0.099–0.327, P = 0.001) and renal failure (coefficient 0.315, 95% CI 0.091–0.540, P = 0.008) were two independent risk factors for in-hospital mortality.

Conclusions: There is an overall high in-hospital mortality of 56.8% in postoperative CHD patients on ECMO. Bleeding is the most common complication during ECMO running with an incidence of 47.1%. Single ventricular physiology and renal failure, as two independent risk factors, may potentially increase in-hospital mortality. Further studies exploring the differences in outcomes between ECMO and other extracorporeal life support strategies are warranted.

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.

Extracorporeal cardiopulmonary resuscitation with low pump flow for blocked modified Blalock-Taussig shunt followed by spontaneous recanalization

A 2-week-old male newborn with a double inlet left ventricle developed a cardiac arrest following modified Blalock-Taussig anastomosis in pediatric intensive care unit. Probable causes of the arrest were hemodynamic instability and thrombosed shunt, which was later recanalized on extracorporeal membrane oxygenation therapy, which was successfully used with a pump flow lower than recommended in these patients-without the shunt clip, but without any complications.

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.

Review on Mechanical Support and Cell-Based Therapies for the Prevention and Recovery of the Failed Fontan-Kreutzer Circulation

Though the current staged surgical strategy for palliation of single ventricle heart disease, culminating in a Fontan circulation, has increased short-term survival, mounting evidence has shown that the single ventricle, especially a morphologic right ventricle (RV), is inadequate for long-term circulatory support. In addition to high rates of ventricular failure, high central venous pressures (CVP) lead to liver fibrosis or cirrhosis, lymphatic dysfunction, kidney failure, and other comorbidities. In this review, we discuss the complications seen with Fontan physiology, including causes of ventricular and multi-organ failure. We then evaluate the clinical use, results, and limitations of long-term mechanical assist devices intended to reduce RV work and high CVP, as well as biological therapies for failed Fontan circulations. Finally, we discuss experimental tissue engineering solutions designed to prevent Fontan circulation failure and evaluate knowledge gaps and needed technology development to realize a more robust single ventricle therapy.

Improved outcomes in neonates who require venoarterial extracorporeal membrane oxygenation after the Norwood procedure

BACKGROUND

Extracorporeal membrane oxygenation after the Norwood procedure has historically been associated with poor outcomes, with reported hospital survival rates of 13%-48%. We hypothesized that contemporary outcomes in this population have improved. We aimed to compare clinical outcomes of contemporary cohorts of patients with functional single ventricle physiology who did and did not receive extracorporeal membrane oxygenation after the Norwood procedure.

METHODS

Single-center retrospective cohort study of patients with single ventricle anatomy who underwent the Norwood procedure between 2009 and 2017 was performed. Kaplan-Meier survival curves were constructed, and Cox proportional hazard regression analyses were performed to compare transplant-free survival in patients who did and did not receive venoarterial extracorporeal membrane oxygenation.

RESULTS

In total, 85 patients met inclusion criteria. Venoarterial extracorporeal membrane oxygenation was utilized in 25 patients (29%). A total of 18 patients (72%) who received venoarterial extracorporeal membrane oxygenation survived to hospital discharge, compared to 54 patients (92%) who did not receive venoarterial extracorporeal membrane oxygenation (p = 0.013). Post-discharge transplant-free survival was not significantly different between patients who did and did not receive venoarterial extracorporeal membrane oxygenation (log-rank p value = 0.28). Cox proportional hazard regression analysis revealed that the occurrence of cardiac arrest requiring cardiopulmonary resuscitation (hazard ratio = 4.5; 95% confidence interval = 2.0-10.1) during the perioperative period was independently associated with death or transplantation, whereas venoarterial extracorporeal membrane oxygenation was not an independent risk factor for death or transplantation (hazard ratio = 2.0; 95% confidence interval = 0.8-4.9).

CONCLUSION

In our cohort of children who received venoarterial extracorporeal membrane oxygenation after the Norwood procedure, hospital survival was improved compared to historical data. In addition, venoarterial extracorporeal membrane oxygenation utilization was not independently associated with worse outcomes.

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.

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.

Hypoplastic left heart syndrome: from fetus to fontan

The care of children with hypoplastic left heart syndrome is constantly evolving. Prenatal diagnosis of hypoplastic left heart syndrome will aid in counselling of parents, and selected fetuses may be candidates for in utero intervention. Following birth, palliation can be undertaken through staged operations: Norwood (or hybrid) in the 1st week of life, superior cavopulmonary connection at 4-6 months of life, and finally total cavopulmonary connection (Fontan) at 2-4 years of age. Children with hypoplastic left heart syndrome are at risk of circulatory failure their entire life, and selected patients may undergo heart transplantation. In this review article, we summarise recent advances in the critical care management of patients with hypoplastic left heart syndrome as were discussed in a focused session at the 12th International Conference of the Paediatric Cardiac Intensive Care Society held on 9 December, 2016, in Miami Beach, Florida.

Mechanical Circulatory Support for Single Ventricle Failure

Mechanical circulatory support (MCS) for failing single ventricle (SV) physiology is a complex and challenging problem, which has not yet been satisfactorily addressed. Advancements in surgical strategies and techniques along with intensive care management have substantially improved the outcomes of neonatal palliation for SV physiology, particularly for hypoplastic left heart syndrome (HLHS). This is associated with a steady increase in the number of SV patients who are susceptible to develop heart failure (HF) and would potentially require MCS at a certain stage in their palliation. We have reviewed the literature regarding the reported modalities of MCS use in the management of SV patients. This includes analysis of various devices and strategies used for failing circulation at distinct stages of the SV pathway: after neonatal palliation, after the superior cavo-pulmonary connection (SCPC), and after total cavo-pulmonary connection (TCPC).

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.

Cardiopulmonary Resuscitation in Infants and Children With Cardiac Disease: A Scientific Statement From the American Heart Association

Cardiac arrest occurs at a higher rate in children with heart disease than in healthy children. Pediatric basic life support and advanced life support guidelines focus on delivering high-quality resuscitation in children with normal hearts. The complexity and variability in pediatric heart disease pose unique challenges during resuscitation. A writing group appointed by the American Heart Association reviewed the literature addressing resuscitation in children with heart disease. MEDLINE and Google Scholar databases were searched from 1966 to 2015, cross-referencing pediatric heart disease with pertinent resuscitation search terms. The American College of Cardiology/American Heart Association classification of recommendations and levels of evidence for practice guidelines were used. The recommendations in this statement concur with the critical components of the 2015 American Heart Association pediatric basic life support and pediatric advanced life support guidelines and are meant to serve as a resuscitation supplement. This statement is meant for caregivers of children with heart disease in the prehospital and in-hospital settings. Understanding the anatomy and physiology of the high-risk pediatric cardiac population will promote early recognition and treatment of decompensation to prevent cardiac arrest, increase survival from cardiac arrest by providing high-quality resuscitations, and improve outcomes with postresuscitation care.

An overview of mechanical circulatory support in single-ventricle patients

The population of people with a single-ventricle is continually increasing due to improvements across the spectrum of medical care. Unfortunately, a proportion of these patients will develop heart failure. Often, for these patients, mechanical circulatory support (MCS) represents the only available treatment option. While single-ventricle patients currently represent a small proportion of the total number of patients who receive MCS, as the single-ventricle patient population increases, this number will increase as well. Outcomes for these complex single-ventricle patients who require MCS has begun to be evaluated. When considering the entire population, survival to hospital discharge is 30-50%, though this must be considered with the significant heterogeneity of the single-ventricle patient population. Patients with a single-ventricle have unique anatomy, mechanisms of failure, indications for MCS and the type of support utilized. This has made the interpretation and the generalizability of the limited available data difficult. It is likely that some subsets will have a significantly worse prognosis and others a better one. Unfortunately, with these limited data, indications of a favorable or poor outcome have not yet been elucidated. Though currently, a database has been constructed to address this issue. While the outcomes for these complex patients is unclear, at least in some situations, they are poor. However, significant advances may provide improvements going forward, including new devices, computer simulations and 3D printed models. The most important factor, however, will be the increased experience gained by the heart failure team to improve patient selection, timing, device and configuration selection and operative approach.

Extracorporeal membrane oxygenation in congenital heart disease

This review article will discuss the indications for and outcomes of neonates with congenital heart disease who receive extracorporeal membrane oxygenation (ECMO) support. Most commonly, ECMO is used as a perioperative bridge to recovery or temporary support for those after cardiac arrest or near arrest in patients with congenital or acquired heart disease. What had historically been considered a contraindication to ECMO, is evolving and more of the sickest and most complicated babies are cared for on ECMO. Given that, it is imperative for aggressive survellience for long-term morbidity in survivors, particularly neurodevelopmental outcomes.

Norwood Procedure for Palliation of Hypoplastic Left Heart Syndrome: Right Ventricle to Pulmonary Artery Conduit vs Modified Blalock-Taussig Shunt

Patients with hypoplastic left heart syndrome undergo a series of operations to separate the pulmonary and systemic circulations. The first of at least 3 operations occurs in the newborn period, with a stage I palliation. The goal of stage I palliation is to provide pulmonary blood flow and create an unobstructed systemic outflow tract. Advances in surgical techniques and intraoperative and postoperative care have helped decrease morbidity and mortality for patients with hypoplastic left heart syndrome who have the stage I Norwood operation, but the patients continue to be at increased risk for hemodynamic collapse and adverse outcomes. This article discusses risk factors, surgical approach, postoperative nursing and medical management strategies, differences between and outcomes for the Norwood operation with the right ventricle to pulmonary artery conduit and the Norwood operation with a modified Blalock-Taussig shunt.

Extracorporeal Cardiopulmonary Resuscitation in the Pediatric Cardiac Population: In Search of a Standard of Care

OBJECTIVES

Although clinical and pharmacologic guidelines exist for the practice of cardiopulmonary resuscitation in children (Pediatric Advanced Life Support), the practice of extracorporeal cardiopulmonary resuscitation in pediatric cardiac patients remains without universally accepted standards. We aim to explore variation in extracorporeal cardiopulmonary resuscitation procedures by surveying clinicians who care for this high-risk patient population.

DESIGN

A 28-item cross-sectional survey was distributed via a web-based platform to clinicians focusing on cardiopulmonary resuscitation practices and extracorporeal membrane oxygenation team dynamics immediately prior to extracorporeal membrane oxygenation cannulation.

SETTINGS

Pediatric hospitals providing extracorporeal mechanical support services to patients with congenital and/or acquired heart disease.

SUBJECTS

Critical care/cardiology specialist physicians, cardiothoracic surgeons, advanced practice nurse practitioners, respiratory therapists, and extracorporeal membrane oxygenation specialists.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Survey web links were distributed over a 2-month period with critical care and/or cardiology physicians comprising the majority of respondents (75%). Nearly all respondents practice at academic/teaching institutions (97%), 89% were from U.S./Canadian institutions and 56% reported less than 10 years of clinical experience. During extracorporeal cardiopulmonary resuscitation, a majority of respondents reported adherence to guideline recommendations for epinephrine bolus dosing (64%). Conversely, 19% reported using only one to three epinephrine bolus doses regardless of extracorporeal cardiopulmonary resuscitation duration. Inotropic support is held after extracorporeal membrane oxygenation cannulation "most of the time" by 58% of respondents and 94% report using afterload reducing/antihypertensive agents "some" to "most of the time" after achieving full extracorporeal membrane oxygenation support. Interruptions in chest compressions are common during active cannulation according to 77% of respondents.

CONCLUSIONS

The results of this survey identify wide variability in resuscitative practices during extracorporeal cardiopulmonary resuscitation in the pediatric cardiac population. The deviations from established Pediatric Advanced Life Support CPR guidelines support a call for further inquiry into the pharmacologic and logistical care surrounding extracorporeal cardiopulmonary resuscitation.

Predictors of Mortality in Children with Pulmonary Atresia with Intact Ventricular Septum

Pulmonary atresia with intact ventricular septum (PA/IVS) is a rare cardiac congenital lesion characterized by imperforate pulmonary valve, intact ventricular septum, and atrial level shunt. Although different management strategies to establish a source of non-ductal dependent pulmonary blood flow have been described, studies have not assessed the relationship between the therapeutic approach, patient characteristics, and outcomes. The purpose of this study was to identify predictors of mortality for patients with PA/IVS. Neonates and children with PA/IVS were identified through analysis of the 2012 Kids' Inpatient Database of the Healthcare Cost and Utilization Project. Hospital admissions that included a cardiac catheterization and/or surgical procedure were analyzed to identify demographics, co-morbidities, and outcomes. We identified 508 patients with PA/IVS with hospital admissions that included cardiac catheterization (n = 165), surgical procedures (n = 273), or both (n = 70). The incidence of mortality in this cohort was 6.69% (34/508). Univariable analysis demonstrated that age less than 12 months (p < 0.001), non-elective admission (p < 0.001), AKI (p = 0.001), sepsis (p = 0.002), and the use of ECMO (p < 0.001) were associated with an increased risk of mortality, while no difference was observed for the type of therapeutic approach (p = 0.498). These variables were used in a multivariable logistic regression analysis to develop the predictive model for mortality. Age less than 12 months, non-elective admission, and the use of ECMO in children with PA/IVS were predictors for mortality. Interestingly, the type of therapeutic approach did not influence mortality, which suggests that patient characteristics other than the method chosen to provide pulmonary blood flow determine mortality.

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.

Interstage Survival for Patients with Hypoplastic Left Heart Syndrome After ECMO

There is a reported 5-20 % incidence of extracorporeal membrane oxygenation (ECMO) following stage I palliation for hypoplastic left heart syndrome (HLHS). This study compares the interstage mortality of HLHS patients supported with ECMO (HLHS-ECMO) to those who were not supported with ECMO (HLHS-nECMO) using the National Pediatric Cardiology Quality Improvement Initiative database. Patients with HLHS who survived to hospital discharge after stage I palliation were analyzed. HLHS-ECMO patients were compared to HLHS-non-ECMO patients with respect to demographics, surgical variables, and interstage survival. A total of 931 patients were identified in the database. Sixty-six (7.1 %) patients were supported with ECMO during their stage I palliation admission. There were no statistically significant differences between the groups with respect to demographics or anatomic subtype. HLHS-ECMO patients were more likely to have a preoperative risk factor identified (62 vs. 48 %, p = 0.03) or require ECMO prior to stage I palliation (3 vs. 0.5 %, p = 0.03). HLHS-ECMO patients had a significantly higher incidence of death or transplant versus the HLHS-nECMO group (18 vs. 9 %, p = 0.03). Despite survival to discharge, patients with HLHS requiring ECMO after their palliation continue to have an increased risk of death/cardiac transplant versus patients that do not require ECMO. ECMO use is likely a marker for a high-risk patient group. These patients may benefit from closer follow-up during the interstage period.

Association of Extracorporeal Membrane Oxygenation Support Adequacy and Residual Lesions With Outcomes in Neonates Supported After Cardiac Surgery

OBJECTIVES

There is a paucity of data regarding the impact of extracorporeal membrane oxygenation support, adequacy of surgical repair, and timing of intervention for residual structural lesions in neonates cannulated to extracorporeal membrane oxygenation after cardiac surgery. Our goal was to determine how these factors were associated with survival.

DESIGN

Retrospective study.

SETTING

Cardiovascular ICU.

SUBJECTS

Neonates (≤ 28 d old) with congenital heart disease cannulated to extracorporeal membrane oxygenation after cardiac surgery during 2006-2013.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Eighty-four neonates were cannulated to venoarterial extracorporeal membrane oxygenation after cardiac surgery. Survival to discharge was 50%. There was no difference in survival based on surgical complexity and those with single or biventricular congenital heart disease. Prematurity (≤ 36 wk gestation; odds ratio, 2.33; p = 0.01), preextracorporeal membrane oxygenation pH less than or equal to 7.17 (odds ratio, 2.01; p = 0.04), need for inotrope support during extracorporeal membrane oxygenation (odds ratio, 3.99; p = 0.03), and extracorporeal membrane oxygenation duration greater than 168 hours (odds ratio, 2.04; p = 0.04) were all associated with increased mortality. Although preextracorporeal membrane oxygenation lactate was not significantly different between survivors and nonsurvivors, unresolved lactic acidosis greater than or equal to 72 hours after cannulation (odds ratio, 2.77; p = 0.002) was associated with increased mortality. Finally, many patients (n = 70; 83%) were noted to have residual lesions after cardiac surgery, and time to diagnosis or correction of residual lesions was significantly shorter in survivors (1 vs 2 d; p = 0.02).

CONCLUSIONS

Our data suggest that clearance of lactate is an important therapeutic target for patients cannulated to extracorporeal membrane oxygenation. In addition, timely identification of residual lesions and expedient interventions on those lesions may improve survival.

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.

Hypoplastic Left Heart Syndrome and Other Shunt-Dependent Single Ventricles

OBJECTIVES

In this review, we discuss the pathophysiology, treatment, and outcomes of patients with the hypoplastic left heart syndrome and other single ventricle variants prior to and following surgery.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSIONS

Patients with shunted single ventricle physiology are at increased risk for acute hemodynamic decompensation owing to the increased myocardial workload, the dynamic balance between systemic and pulmonary circulations, and the potential for shunt obstruction. Understanding of the physiology and anticipatory management are critical to prevent hemodynamic compromise and cardiac arrest.

Validation of a Simple Score to Determine Risk of Hospital Mortality After the Norwood Procedure

The ability to quantify patient-specific hospital mortality risk before the Norwood procedure remains elusive. This study aimed to develop an accurate and clinically feasible score to assess the risk of hospital mortality in neonates undergoing the Norwood procedure. All patients (n = 549) in the publically available Pediatric Heart Network Single Ventricle Reconstruction trial database were included in the analysis. Patients were randomly divided into a derivation (75%) and validation (25%) cohort. Preoperative factors found to be associated with mortality upon univariable analysis (P < 0.2) were included in the logistic regression model. The score was derived by including variables independently associated with mortality (P < 0.05). A 20-point score using 6 variables (birth weight, clinical syndrome or abnormal karyotype, surgeon Norwood volume or year, anatomic subtype, ascending aorta size, and obstructed pulmonary venous return) was developed using relative magnitudes of the covariates׳ odds ratio. The score was then tested in the validation cohort. In weighted regression analysis, model predicted risk of mortality correlated closely with actual rates of mortality in the derivation (R² = 0.87, P < 0.01) and validation cohorts (R² = 0.82, P < 0.01). Patients were classified as low (score: 0-5), medium (6-10), or high risk (>10). Mortality differed significantly between risk groups in both the derivation (6% vs 22% vs 77%, P < 0.01) and validation (4% vs 30% vs 53%, P < 0.01) cohorts. This mortality score is accurate in determining risk of hospital mortality in neonates undergoing planned Norwood operations. The score has the potential to be used in clinical practice to aid in risk assessment before surgery. Clinical trial registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00115934.

Extracorporeal membrane oxygenator support in infants with systemic-pulmonary shunts

BACKGROUND

Management of a patent systemic-pulmonary (SP) shunt and the resulting runoff during extracorporeal membrane oxygenation (ECMO) varies among institutions. We have used a strategy of increased flow without surgical reduction of the shunt diameter, and here report our results with this strategy.

METHODS

In this database review of 169 successive veno-arterial ECMO runs performed between 2002 and 2013 in infants and neonates, ECMO flow, time to achieve lactate clearance, normal pH, and negative fluid balance were compared in patients with shunts and those without shunts.

RESULTS

Fifty-one of 169 infants (30.2%) had a shunt in situ when ECMO was initiated. Significantly higher ECMO flows were maintained in the shunt group compared with the nonshunt group (161 ± 43 mL/kg/minute vs 134 ± 41 mL/kg/minute; P < .001). Infants with shunts had significantly higher pre-ECMO and peak lactate levels (12.4 ± 5.6 mmol/L vs 10.0 ± 6.3 mmol/L; P < .05 and 13.7 ± 4.9 mmol/L vs 11.6 ± 5.5 mmol/L; P < .02, respectively) and required a longer period of support for clearance (median, 28.8 hours [16.1-63.3 hours] vs 17.5 hours [10.8-34.5 hours]; P < .001). Although the absolute rate of lactate clearance was not significantly different between the 2 groups (median, 0.46 mmol/L/hour [0.12-0.72 mmol/L/hour] vs 0.48 mmol/L/hour [0.22-0.86 mmol/L/hour]; P = .139) the presence of a shunt, neonatal age, peak lactate, extracorporeal cardiopulmonary resuscitation, and the use of hemofiltration on ECMO significantly predicted the rate of clearance. Survival to hospital discharge was similar in the shunt and nonshunt groups (49.0% vs 48.3%; P = .932).

CONCLUSIONS

A strategy of increased ECMO flow without surgically restricting shunt diameter appears to be successful in providing circulatory support in the majority of patients with an SP shunt. Equivalent survival suggests that routine surgical reduction of shunt diameter is not indicated.

Outcomes of Single-Ventricle Patients Supported With Extracorporeal Membrane Oxygenation

OBJECTIVES

Extracorporeal membrane oxygenation is often used in children with single-ventricle anomalies. We aimed to describe extracorporeal membrane oxygenation use in single-ventricle patients to test the hypothesis that despite increasing prevalence, mortality has not improved and overall burden measure by hospital charges and length of stay have increased.

DESIGN

Retrospective analysis of the Healthcare Cost and Utilization Project Kids' Inpatient Database was performed with sample weighting to generate national estimates.

PATIENTS

Pediatric patients (age ≤ 20) with a diagnosis of single ventricle heart disease requiring extracorporeal membrane oxygenation support from 2000 to 2009.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Seven hundred one children (95% CI, 559-943) with single ventricle were supported with extracorporeal membrane oxygenation in the reporting period. Mortality was 57% and did not improve over time (2000 = 52%, 2003 = 63%, 2006 = 57%, and 2009 = 55%; p = 0.66). Single-ventricle patients who required extracorporeal membrane oxygenation were more likely to have had a cardiac procedure (90% vs 46%; p < 0.001), a diagnosis of arrhythmia (22% vs 13%; p < 0.001), cerebrovascular or neurologic insult (9% vs 1%; p < 0.001), heart failure (24% vs 12%; p < 0.001), acute renal failure (28% vs 3%; p < 0.001), or sepsis (28% vs 8%; p < 0.001). By multivariable analysis, acute renal failure was a risk factor for mortality (adjusted odds ratio, 3.12; 95% CI, 1.95-4.98; p < 0.001). The length of stay for single-ventricle patients with extracorporeal membrane oxygenation increased from 25.2 days in 2000 to 55.6 days in 2009 (p < 0.001). Total inflation-adjusted charges increased from $358,021 (95% CI, $278,658-439,765) in 2000 to $732,349 (95% CI, $671,781-792,917) in 2009 (p < 0.001).

CONCLUSIONS

Extracorporeal membrane oxygenation support is uncommon with single-ventricle admissions occurring in 2.3% of all hospitalizations. Among those patients, the mortality rate was 57% with no change over time. Acute renal failure was an independent risk factor for mortality during hospitalization. In addition, length of stay for these patients increased and hospital charges doubled. Further studies are needed to determine suitability and cost-effectiveness of extracorporeal membrane oxygenation in single-ventricle patients.