Outcomes of infants weighing three kilograms or less requiring extracorporeal membrane oxygenation after cardiac surgery

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.

Association between Serum Lactate and Morbidity and Mortality in Neonates: A Systematic Review and Meta-Analysis

OBJECTIVE

Lactate is a marker of hypoperfusion in critically ill patients. Whether lactate is useful for identifying and stratifying neonates with a higher risk of adverse outcomes remains unknown. This study aimed to investigate the association between lactate and morbidity and mortality in neonates.

METHODS

A meta-analysis was performed to determine the association between blood lactate levels and outcomes in neonates. Ovid MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov were searched from inception to 1 May 2021. A total of 49 observational studies and 14 data accuracy test studies were included. The risk of bias was assessed using the Newcastle-Ottawa Scale for observational studies and the QUADAS-2 tool for data accuracy test studies. The primary outcome was mortality, while the secondary outcomes included acute kidney injury, necessity for renal replacement therapy, neurological outcomes, respiratory morbidities, hemodynamic instability, and retinopathy of prematurity.

RESULTS

Of the 3184 articles screened, 63 studies fulfilled all eligibility criteria, comprising 46,069 neonates. Higher lactate levels are associated with mortality (standard mean difference, -1.09 [95% CI, -1.46 to -0.73]). Using the estimated sensitivity (0.769) and specificity (0.791) and assuming a prevalence of 15% for adverse outcomes (median of prevalence among studies) in a hypothetical cohort of 10,000 neonates, assessing the lactate level alone would miss 346 (3.46%) cases (false negative) and wrongly diagnose 1776 (17.76%) cases (false positive).

CONCLUSIONS

Higher lactate levels are associated with a greater risk of mortality and morbidities in neonates. However, our results do not support the use of lactate as a screening test to identify adverse outcomes in newborns. Research efforts should focus on analyzing serial lactate measurements, rather than a single measurement.

Survival-to-Hospital Discharge in Neonates With Congenital Heart Disease Supported With Prolonged Extracorporeal Membrane Oxygenation

Factors that determine early outcomes in neonates with congenital heart disease (CHD) supported with prolonged venoarterial extracorporeal membrane oxygenation (ECMO) are not known and contemporary multicenter data are limited. This Extracorporeal Life Support Organization registry-based retrospective cohort study included all neonates (age ≤28 days) with CHD supported with venoarterial ECMO >7 days at 111 centers in the United States from January 2011 to December 2020. The primary outcome was survival-to-hospital discharge, and the secondary outcome was ECMO survival (successful decannulation before hospital discharge or death). Of the 2,155 total ECMO runs, 948 neonates received prolonged ECMO (gestational age [mean ± SD] 37.9 ± 1.8 weeks; birth weight 3.1 ± 0.6 kg; ECMO duration 13.6 ± 11.2 days). The ECMO survival rate was 51.6% (489 of 948), and the survival-to-hospital discharge rate was 23.9% (226 of 948). Body weight at ECMO (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.44 to 0.78/kg), gestational age (OR 0.89, 95% CI 0.79 to 1.00 per week), risk-adjusted congenital heart surgery-1 score (OR 1.22, 95% CI 1.04 to 1.45), and pump flow at 24 hours (OR 1.11, 95% CI 1.04 to 1.18 per 10 ml/kg/min) were significantly associated with survival-to-hospital discharge. Pre-ECMO mechanical ventilation duration, time to extubation after ECMO decannulation, and length of stay were inversely associated with hospital survival. Patient-specific (higher body weight and gestational age) and CHD-related (lower risk-adjusted congenital heart surgery-1 score) attributes are associated with better outcomes in neonates who receive prolonged venoarterial ECMO. Further elucidation of the factors associated with reduced survival to discharge in ECMO survivors is needed.

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.

Machine learning predicts blood lactate levels in children after cardiac surgery in paediatric ICU

BACKGROUND

Although serum lactate levels are widely accepted markers of haemodynamic instability, an alternative method to evaluate haemodynamic stability/instability continuously and non-invasively may assist in improving the standard of patient care. We hypothesise that blood lactate in paediatric ICU patients can be predicted using machine learning applied to arterial waveforms and perioperative characteristics.

METHODS

Forty-eight post-operative children, median age 4 months (2.9-11.8 interquartile range), mean baseline heart rate of 131 beats per minute (range 33-197), mean lactate level at admission of 22.3 mg/dL (range 6.3-71.1), were included. Morphological arterial waveform characteristics were acquired and analysed. Predicting lactate levels was accomplished using regression-based supervised learning algorithms, evaluated with hold-out cross-validation, including, basing prediction on the currently acquired physiological measurements along with those acquired at admission, as well as adding the most recent lactate measurement and the time since that measurement as prediction parameters. Algorithms were assessed with mean absolute error, the average of the absolute differences between actual and predicted lactate concentrations. Low values represent superior model performance.

RESULTS

The best performing algorithm was the tuned random forest, which yielded a mean absolute error of 3.38 mg/dL when predicting blood lactate with updated ground truth from the most recent blood draw.

CONCLUSIONS

The random forest is capable of predicting serum lactate levels by analysing perioperative variables, including the arterial pressure waveform. Thus, machine learning can predict patient blood lactate levels, a proxy for haemodynamic instability, non-invasively, continuously and with accuracy that may demonstrate clinical utility.

Development of a Model for the Pediatric Survival After Veno-Arterial Extracorporeal Membrane Oxygenation Score: The Pedi-SAVE Score

Pediatric cardiac extracorporeal membrane oxygenation (ECMO) patients have high mortality rates. The purpose of our study was to develop and validate the Pediatric Survival After Veno-arterial ECMO (Pedi-SAVE) score for predicting survival at hospital discharge after pediatric cardiac veno-arterial (VA) ECMO. We used data for pediatric cardiac VA-ECMO patients from the Extracorporeal Life Support Organization registry (1/1/2001-12/31/2015). Development and validation cohorts were created using 2:1 random sampling. Predictors of survival to develop pre- and postcannulation models were selected using multivariable logistic regression and random forest models. ß-coefficients were standardized to create the Pedi-SAVE score. Of 10,091 pediatric cardiac VA-ECMO patients, 4,996 (50%) survived to hospital discharge. Pre- and postcannulation Pedi-SAVE scores predicted that the lowest risk patients have a 65% and 74% chance of survival at hospital discharge, respectively, compared to 33% and 22% in the highest risk patients. In the validation cohort, pre- and postcannulation Pedi-SAVE scores had c-statistics of 0.64 and 0.71, respectively. Precannulation factors associated with survival included: nonsingle ventricle congenital heart disease, older age, white race, lower STAT mortality category, higher pH, not requiring acid-buffer administration, <2 cardiac procedures, and indication for VA-ECMO other than failure to wean from cardiopulmonary bypass. Postcannulation, additional factors associated with survival included: lower ECMO pump flows at 24 hours and lack of complications. The Pedi-SAVE score is a novel validated tool to predict survival at hospital discharge for pediatric cardiac VA-ECMO patients, and is an important advancement in risk adjustment and benchmarking for this population.

Premature and Extracorporeal Life Support: Is it Time? A Systematic Review

Early preterm birth < 34 gestational weeks (GA) and birth weight (BW) <2 kg are relative contraindications for extracorporeal membrane oxygenation (ECMO). However, with improved technology, ECMO is presently managed more safely and with decreasing complications. Thus, these relative contraindications may no longer apply. We performed a systematic review to evaluate the existing literature on ECMO in early and late (34-37 GA) prematurity focusing on survival to hospital discharge and the complication intracranial hemorrhage (ICH). Data sources: MEDLINE, PubMed, Web of Science, Embase, and the Cochrane Database. Only publications in the English language were evaluated. Of the 36 included studies, 23 were related to ECMO support for respiratory failure, 10 for cardiac causes, and four for congenital diaphragmatic hernia (CDH). Over the past decades, the frequency of ICH has declined (89-21%); survival has increased in both early prematurity (25-76%), and in CDH (33-75%), with outcome similar to late prematurity (48%). The study was limited by an inherent risk of bias from overlapping single-center and registry data. Both the risk of ICH and death have decreased in prematurely born treated with ECMO. We challenge the 34 week GA time limit for ECMO and propose an international task force to revise current guidelines. At present, gestational age < 34 weeks might no longer be considered a contraindication for ECMO in premature neonates.

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.

The Outcome of Post-cardiotomy Extracorporeal Membrane Oxygenation in Neonates and Pediatric Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

Post-cardiotomy extracorporeal membrane oxygenation (PC-ECMO) is a known rescue therapy for neonates and pediatric patients who failed to wean from cardiopulmonary bypass (CPB) or who deteriorate in intensive care unit (ICU) due to various reasons such as low cardiac output syndrome (LCOS), cardiac arrest and respiratory failure. We conducted a systematic review and meta-analysis to assess the survival in neonates and pediatric patients who require PC-ECMO and sought the difference in survivals by each indication for PC-ECMO.

DESIGN

Systematic review and meta-analysis.

SETTING

Multi-institutional analysis.

PARTICIPANTS

Neonates and pediatric patients who requires PC- ECMO.

INTERVENTIONS

ECMO after open-heart surgery.

RESULTS

Twenty-six studies were included in the analysis with a total of 186,648 patients and the proportion of the population who underwent PC-ECMO was 2.5% (2,683 patients). The overall pooled proportion of survival in this population was 43.3% [95% Confidence interval (CI): 41.3-45.3%; I ²: 1%]. The survival by indications of PC-ECMO were 44.6% (95% CI: 42.6-46.6; I ²: 0%) for CPB weaning failure, 47.3% (95% CI: 39.9-54.7%; I ²: 5%) for LCOS, 37.6% (95% CI: 31.0-44.3%; I ²: 32%) for cardiac arrest and 47.7% (95% CI: 32.5-63.1%; I ²: 0%) for respiratory failure. Survival from PC-ECMO for single ventricle or biventricular physiology, was reported by 12 studies. The risk ratio (RR) was 0.74 for survival in patients with single ventricle physiology (95% CI: 0.63-0.86; I ²: 40%, P < 0.001). Eight studies reported on the survival after PC-ECMO for genetic conditions. The RR was 0.93 for survival in patients with genetic condition (95% CI: 0.52-1.65; I ²: 65%, P = 0.812).

CONCLUSIONS

PC-ECMO is an effective modality to support neonates and pediatric patients in case of failed CPB weaning and deterioration in ICU. Even though ECMO seems to improve survival, mortality and morbidity remain high, especially in neonates and pediatric patients with single ventricle physiology. Most genetic conditions alone should not be considered a contraindication to ECMO support, further studies are needed to determine which genetic abnormalities are associated with favorable outcome.

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.

Extracorporeal Membrane Oxygenation Support for Failure to Wean From Cardiopulmonary Bypass After Pediatric Cardiac Surgery: Analysis of Extracorporeal Life Support Organization Registry Data

Supplemental Digital Content is available in the text.

Objectives:

Extracorporeal membrane oxygenation has been used to support children who fail to wean from cardiopulmonary bypass after pediatric cardiac surgery, but little is known about outcomes. We aimed to describe epidemiology and extracorporeal membrane oxygenation factors associated with inhospital mortality in these patients.

Design:

Retrospective multicenter registry-based cohort study.

Setting:

International pediatric extracorporeal membrane oxygenation centers.

Patients:

Children less than 18 years old supported with extracorporeal membrane oxygenation for failure to wean from cardiopulmonary bypass after cardiac surgery during 2000–2016 and reported to Extracorporeal Life Support Organization’s registry.

Intervention:

None.

Measurements and Main Results:

The primary outcome measure was inhospital mortality. Cardiac surgical procedural complexity was assigned using risk adjustment in congenital heart surgery-1. Multivariable logistic regression was used to identify factors independently associated with the primary outcome. We included 2,322 patients, with a median age of 26 days (interquartile range, 7–159); 47% underwent complex surgical procedures (risk adjustment in congenital heart surgery 4–6 categories). Inhospital mortality was 55%. The multivariable model evaluating associations with inhospital mortality showed noncardiac congenital anomalies (odds ratio, 1.78; CI, 1.36–2.32), comorbidities (odds ratio, 1.59; CI, 1.30–1.94), preoperative cardiac arrest (odds ratio, 1.67; CI, 1.20–2.34), preoperative mechanical ventilation greater than 24 hours (odds ratio, 1.49; CI, 1.21–1.84), preoperative bicarbonate administration (odds ratio, 1.42; CI, 1.08–1.86), longer cardiopulmonary bypass time (> 251 min; odds ratio, 1.50; CI, 1.13–1.99), complex surgical procedures (odds ratio, 1.43; CI, 1.13–1.81), longer extracorporeal membrane oxygenation duration (> 104 hr, odds ratio, 1.54; CI, 1.17–2.02), and extracorporeal membrane oxygenation complications increased the odds of inhospital mortality. Age greater than 26 days (odds ratio, 0.56; CI, 0.42–0.75) reduced the odds of mortality.

Conclusions:

Children supported with extracorporeal membrane oxygenation for failure to wean from cardiopulmonary bypass after cardiac surgery are at high risk of mortality (55%). Younger patients, those with congenital abnormalities and comorbidities, undergoing complex procedures, requiring longer cardiopulmonary bypass, and experiencing extracorporeal membrane oxygenation complications and longer extracorporeal membrane oxygenation duration have higher mortality risk. These data can help assessing prognosis in this high-risk population.

Extracorporeal Membrane Oxygenation in Infants Undergoing Truncus Arteriosus Repair

BACKGROUND

Infants undergoing truncus arteriosus (TA) repair suffer one of the highest mortality rates of all congenital heart defects. Extracorporeal membrane oxygenation (ECMO) can support patients undergoing TA repair, but little is known about factors contributing to mortality in this cohort. The objective of this study was to identify risk factors for mortality in infants with TA requiring perioperative ECMO.

METHODS

Data from the Extracorporeal Life Support Organization from 2002 to 2017 for infants less than 60 days old undergoing TA repair were analyzed. Demographics, clinical characteristics, and ECMO characteristics and complications were compared between survivors and nonsurvivors. Multivariable logistic regression was used to evaluate independent risk factors for mortality.

RESULTS

Of 245 patients analyzed, 92 (37.6%) survived to discharge. Nonsurvivors had a lower weight and a longer ECMO duration. A higher proportion of nonsurvivors suffered complications on ECMO, including mechanical complications, circuit thrombus, bleeding, and need for renal replacement therapy. In multivariable analysis lower weight (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.33-0.95), duration of ECMO (OR, 1.1; 95% CI, 1.02-1.18), need for renal replacement therapy (OR, 3.23; 95% CI, 1.68-6.2), cardiopulmonary resuscitation on ECMO (OR, 11.52; 95% CI, 1.3-102.33), and infection on ECMO (OR, 4.47; 95% CI, 1.2-16.64) were independently associated with mortality.

CONCLUSIONS

Many factors associated with mortality for infants requiring perioperative ECMO with TA repair are related to complications suffered on ECMO. Thoughtful patient selection and meticulous ECMO management to prevent complications are essential in improving outcomes for these infants.

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.

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.

Extracorporeal membrane oxygenation, Berlin, and ventricular assist devices: a primer for the cardiologist

PURPOSE OF REVIEW

Mechanical circulatory support (MCS) has become an indispensable tool in the management of children with impending respiratory and cardiac failure. Though extracorporeal membrane oxygenation (ECMO) was classically the only form of support available to pediatric patients, considerable advances have allowed ventricular assist devices (VADs) to become increasingly utilized in children. This review provides an update of recent advances in ECMO and VAD management in children.

RECENT FINDINGS

The options for mechanical support in infants and small children with end-stage heart failure are limited. As such, the greatest advances in the past decade have come in the successful adoption of the Berlin Heart EXCOR device, with a marked improvement in survival to transplant over ECMO. Further advances have been made in the use of adult VADs in children. For instance, the HeartWare HVAD has been utilized in children as young as 3 years of age, despite being designed for use in adult patients.

SUMMARY

The availability of mechanical support options for children remains limited to ECMO and a small number of VADs. While outcomes of VAD support in pediatric patients have been promising, further study in smaller and more complex pediatric patients is necessary.

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.

Extracorporeal Membrane Oxygenation in a 1,360-g Premature Neonate after Repairing Total Anomalous Pulmonary Venous Return

With advancements in complex repairs in neonates with complicated congenital heart diseases, extracorporeal membrane oxygenation (ECMO) has been increasingly used as cardiac support. ECMO has also been increasingly used for low birth weight (LBW) or very low birth weight (VLBW) neonates. However, since prematurity and LBW are risk factors for ECMO, the appropriate indications for neonates with LBW, especially VLBW, are under dispute. We report a case of ECMO performed in a 1,360-g premature infant with VLBW due to cardiopulmonary bypass weaning failure after repairing infracardiac total anomalous pulmonary venous return.

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.

Extracorporeal Life Support for Pediatric Heart Failure

Extracorporeal life support (ECLS) represents an essential component in the treatment of the pediatric patient with refractory heart failure. Defined as the use of an extracorporeal system to provide cardiopulmonary support, ECLS provides hemodynamic support to facilitate end-organ recovery and can be used as a salvage therapy during acute cardiorespiratory failure. Support strategies employed in pediatric cardiac patients include bridge to recovery, bridge to therapy, and bridge to transplant. Advances in extracorporeal technology and refinements in patient selection have allowed wider application of this therapy in pediatric heart failure patients.

ECLS in Pediatric Cardiac Patients

Extracorporeal life support (ECLS) is an important device in the management of children with severe refractory cardiac and or pulmonary failure. Actually, two forms of ECLS are available for neonates and children: extracorporeal membrane oxygenation (ECMO) and use of a ventricular assist device (VAD). Both these techniques have their own advantages and disadvantages. The intra-aortic balloon pump is another ECLS device that has been successfully used in larger children, adolescents, and adults, but has found limited applicability in smaller children. In this review, we will present the "state of art" of ECMO in neonate and children with heart failure. ECMO is commonly used in a variety of settings to provide support to critically ill patients with cardiac disease. However, a strict selection of patients and timing of intervention should be performed to avoid the increase in mortality and morbidity of these patients. Therefore, every attempt should be done to start ECLS "urgently" rather than "emergently," before the presence of dysfunction of end organs or circulatory collapse. Even though exciting progress is being made in the development of VADs for long-term mechanical support in children, ECMO remains the mainstay of mechanical circulatory support in children with complex anatomy, particularly those needing rapid resuscitation and those with a functionally univentricular circulation. With the increase in familiarity with ECMO, new indications have been added, such as extracorporeal cardiopulmonary resuscitation (ECPR). The literature supporting ECPR is increasing in children. Reasonable survival rates have been achieved after initiation of support during active compressions of the chest following in-hospital cardiac arrest. Contraindications to ECLS have reduced in the last 5 years and many centers support patients with functionally univentricular circulations. Improved results have been recently achieved in this complex subset of patients.

Impact of Kidney Disease on Survival in Neonatal Extracorporeal Life Support

OBJECTIVE

To investigate the prevalence and survival to discharge of neonates with kidney disease who received extracorporeal life support.

DESIGN

We analyzed the Extracorporeal Life Support Organization international registry of neonates (< 30 d old) who received extracorporeal life support from 1989 to 2012. We used International Classification of Diseases and Related Health Problems, 9th Revision, Clinical Modification, codes to identify neonates with kidney disease at time of cannulation for extracorporeal life support.

SETTING

Participating Extracorporeal Life Support Organization centers.

PATIENTS

All neonates who received extracorporeal life support at an Extracorporeal Life Support Organization center from 1989 to 2012.

INTERVENTIONS

We performed bivariate logistic regression to estimate associations between survival and covariates. We used unadjusted and adjusted logistic regression to compare survival to discharge between neonates with and without kidney disease. Odds ratios were estimated separately for three groups based on extracorporeal life support indication: pulmonary indication without congenital diaphragmatic hernia, pulmonary indication with congenital diaphragmatic hernia, and cardiac indication. Adjusted models included covariates identified as significant in bivariate models for each group.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measure was survival to discharge from hospitalization. Of the 28,755 neonates who received extracorporeal life support, 405 had kidney disease (extracorporeal life support indication: 210 pulmonary indication without congenital diaphragmatic hernia, 65 pulmonary indication with congenital diaphragmatic hernia, and 130 cardiac indication). Survival was lower in neonates with kidney disease than those without (49% vs 82% pulmonary indication without congenital diaphragmatic hernia, 25% vs 51% pulmonary indication with congenital diaphragmatic hernia, 21% vs 41% cardiac indication). Kidney disease was associated with reduced survival in adjusted models (95% CI for odds ratio 0.31-0.59 pulmonary indication without congenital diaphragmatic hernia, 0.27-0.89 pulmonary indication with congenital diaphragmatic hernia, 0.31-0.77 cardiac indication).

CONCLUSIONS

Neonates with kidney disease who receive extracorporeal life support have poorer survival to discharge compared with other neonates who receive extracorporeal life support, suggesting that kidney disease should be considered when making extracorporeal life support initiation decisions.

Neurologic injury in neonates with congenital heart disease during extracorporeal membrane oxygenation: an analysis of extracorporeal life support organization registry data

The aim of this article is to describe the epidemiology and factors associated with acute neurologic injury in neonates with congenital heart disease (CHD) undergoing extracorporeal membrane oxygenation (ECMO). It is a retrospective cohort study. Multi-institutional data for purposes of this study were obtained from the extracorporeal life support organization registry Neonates with CHD supported with ECMO during 2005-2010. Of 1,898 neonates with CHD supported with ECMO, 273 (14%) had neurologic injury. Birth weight less than 3 kg (odds ratio [OR]: 1.5; 95% confidence intervals [CI]: 1.1-1.9), pre-ECMO blood pH ≤ 7.15 (OR: 1.5, 95% CI: 1.1-2.1) need for cardiopulmonary resuscitation before ECMO (OR: 1.7, 95% CI: 1.5-2.0) increased neurologic injury. In-hospital mortality was higher in patients with neurologic injury compared with those without (73% vs. 53%; p < 0.001). Neonates with CHD undergoing ECMO are highly vulnerable to acute neurologic injury regardless of cardiac lesion-specific physiology or the occurrence of cardiac surgery. The incidence of neurologic injuries in this population is higher in sicker patients. Severity of illness should therefore become the main target for improvement. Timely deployment of ECMO may therefore influence the development of ECMO complications.

Clinical Applications of Extracorporeal Membranous Oxygenation: A Mini-Review

The clinical usage of extracorporeal membranous oxygenation began more than 40 years ago. Although the indications for its use have expanded over the years, it has been challenging to conduct randomized controlled trials to prove that extracorporeal membranous oxygenation is more effective than traditional approaches. Through a review of retrospective reports and data from registries, we attempted to evaluate the appropriateness of its application for acute respiratory distress syndrome, cardiopulmonary resuscitation, postcardiotomy cardiogenic shock, and sepsis. Our investigation revealed that using extracorporeal membranous oxygenation when readily available is appropriate for all patients with cardiopulmonary resuscitation or postcardiotomy cardiogenic shock, and for selected patients with acute respiratory distress syndrome or sepsis.

KEY WORDS

Acute respiratory distress syndrome; Cardiopulmonary resuscitation; Extracorporeal membranous oxygenation; Postcardiotomy cardiogenic shock; Sepsis.

Perioperative pharmacological management of pulmonary hypertensive crisis during congenital heart surgery

Pulmonary hypertensive crisis is an important cause of morbidity and mortality in patients with pulmonary arterial hypertension secondary to congenital heart disease (PAH-CHD) who require cardiac surgery. At present, prevention and management of perioperative pulmonary hypertensive crisis is aimed at optimizing cardiopulmonary interactions by targeting prostacyclin, endothelin, and nitric oxide signaling pathways within the pulmonary circulation with various pharmacological agents. This review is aimed at familiarizing the practitioner with the current pharmacological treatment for dealing with perioperative pulmonary hypertensive crisis in PAH-CHD patients. Given the life-threatening complications associated with pulmonary hypertensive crisis, proper perioperative planning can help anticipate cardiopulmonary complications and optimize surgical outcomes in this patient population.

Extracorporeal life support for the neonatal cardiac patient: outcomes and new directions

Extracorporeal life support is an important therapy for neonates with life-threatening cardiopulmonary failure. Utilization of extracorporeal life support in neonates with congenital heart disease has increased dramatically during the past three decades. Despite increased usage, overall survival in these patients has changed very little and extracorporeal life support-related morbidity, including bleeding, neurologic injury, and renal failure, remains a major problem. Although survival is lower and neurologic complications are higher in premature infants than term infants, cardiac extracorporeal life support including extracorporeal cardiopulmonary resuscitation is effective in preventing death in many of these high-risk patients. Miniaturized ventricular assist devices and compact integrated extracorporeal life support systems are being developed to provide additional therapeutic options for neonates.