Extracorporeal Membrane Oxygenation Population Research Articles

Assessing Kidney Transplantation Using ECMO-Supported Donors Within a KDPI-Based Allocation System.

Organ donors supported by extracorporeal membrane oxygenation (ECMO) have historically been considered high-risk and are judiciously utilized. This study examines transplant outcomes using renal allografts from donors supported on ECMO for nondonation purposes. Retrospective review of the Gift of Life (Pennsylvania, New Jersey, Delaware) organ procurement organization database, cross-referenced to the Organ Procurement and Transplantation Network database, assessed kidney transplants using donors supported on venoarterial (VA) and venovenous (VV) ECMO for nondonation purposes. Transplants using VA- and VV-ECMO donors were compared with Kidney Donor Profile Index (KDPI)-stratified non-ECMO donors. Regression modeling of the entire ECMO and non-ECMO populations assessed ECMO as predictive of graft survival. Additional regression of the ECMO population alone assessed for donor features associated with graft survival. Seventy-eight ECMO donors yielded 128 kidney transplants (VA: 80, VV: 48). Comparing outcomes using these donors to kidney transplants using organs from KDPI-stratified non-ECMO donors, VA- and VV-ECMO donor grafts conferred similar rates of delayed graft function and posttransplant renal function to KDPI-matched non-ECMO counterparts. VA-ECMO kidneys demonstrated superior graft survival compared with the lowest-quality (KDPI 86%-100%) non-ECMO kidneys and similar graft survival to KDPI <85% non-ECMO kidneys. VV-ECMO showed inferior graft survival to all but the lowest-quality (KDPI 86%-100%) non-ECMO kidneys. VV-ECMO, but not VA-ECMO, was associated with increased risk of graft loss on multivariable regression (hazard ratios-VA: 1.02, VV: 2.18). Higher KDPI, advanced age, increased body mass index, hypertension, and diabetes were identified as high-risk features of ECMO donors. Kidney transplantation using appropriately selected ECMO donors can safely expand the donor pool. Ongoing studies are necessary to determine best practice patterns using kidneys from these donors.

Continuous Electroencephalography (EEG) Protocol Improves Seizure Detection in Children on Extracorporeal Membrane Oxygenation.

Seizures are a complication for pediatric patients requiring extracorporeal membrane oxygenation (ECMO). There are no standardized guidelines regarding continuous electroencephalography (EEG) monitoring to detect seizures in these patients, and the impact of protocolized monitoring has not been evaluated. Here we examined the effects of continuous EEG protocol implementation in our pediatric ECMO population. Retrospective chart reviews were conducted on 57 patients who underwent extracorporeal membrane oxygenation and concurrent continuous EEG out of 165 patients supported on extracorporeal membrane oxygenation. Timing of continuous EEG initiation and seizures detected by continuous EEG was determined for 5 years prior to and 15 months after protocol implementation. Protocol implementation was associated with increased ECMO-supported patients who were concurrently monitored by continuous EEG. Time from ECMO cannulation to continuous EEG initiation was shorter (median 7 hours after versus 16.2 hours before; P < .001). Patients who had ongoing seizures at the start of continuous EEG recording decreased from 64% preprotocol to 0% postprotocol (P < .001), and there was an associated earlier time to break in status epilepticus postprotocol. Seizures were detected past 48 hours after cannulation in 50% of patients in the postprotocol group. Protocol implementation resulted in earlier continuous EEG initiation and more EEGs initiated before seizure onset with evidence of altered seizure dynamics. Although current recommendations suggest that continuous EEG duration of 24-48 hours results in seizure detection for >90% of critically ill adults, longer monitoring may be needed to reliably detect seizures in children supported with ECMO, particularly if monitoring is initiated earlier in the post-cannulation period.

Extracorporeal membrane oxygenation as a bridge to lung transplantation: Practice patterns and patient outcomes

Extracorporeal membrane oxygenation (ECMO) is increasingly relied on to bridge patients with respiratory failure to lung transplantation despite limited evidence for its use in this setting. This study evaluated longitudinal trends in practice patterns, patient characteristics, and outcomes in patients bridged with ECMO to lung transplant. A retrospective review of all adult isolated lung transplant patients in the United Network for Organ Sharing database between 2000 and 2019 was performed. Patients were classified as "ECMO" if supported with ECMO at the time of listing or transplantation and "non-ECMO" otherwise. Linear regression was used to evaluate trends in patient demographics during the study period. Trends in mortality were evaluated using Cox proportional hazards modeling, with time period as the primary covariate (2000-2004, 2005-2009, 2010-2014, or 2015-2019) and age, time on the waitlist, and underlying diagnosis as covariates. The number of patients included were 40,866, of whom 1,387 (3.4%) were classified as ECMO and 39,479 (96.6%) as no ECMO. Average age and initial Lung Allocation Score increased significantly during the study period in both cohorts, but occurred at a slower rate in the ECMO population. The hazard of death was significantly lower in more recent years (2015-2019) for both the ECMO and non-ECMO cohorts (aHR (adjusted hazards ratio) 0.59, 95% confidence interval (CI) 0.37-0.96 and aHR 0.74, 95% CI 0.70-0.79) when compared to the early years (2000-2004) of the study period. Post-transplantation survival for patients bridged to transplantation with ECMO demonstrates ongoing improvement despite cannulation of progressively older and sicker patients.

Cannulate, Extubate, Ambulate: How the Pandemic Accelerated Development and Implementation of Early Mobility for Patients Requiring Extracorporeal Membrane Oxygenation

Objective: Extracorporeal membrane oxygenation (ECMO) is a lifesaving modality that was in great demand for persons with severe COVID-19 infection. Although mobility of these patients has previously been safely reported anecdotally, there were no established guidelines to implement in a greatly expanded patient population, as occurred in the pandemic period. We describe the development and implementation of a program (Cannulate, Extubate, Ambulate) for team-based safe mobilization. Methods: The 3-phase protocol advances based on patient alertness/ability to actively participate. A physical therapist determined initial stage and progression and recommended mobility activities for carryover by nurses and/or ECMO specialists between skilled sessions. Results: The mobility program has been successfully implemented for 104 patients with severe COVID-19 without significant adverse events. Most patients (51%) ambulated while cannulated, and 60% were able to discharge directly home after hospitalization. Conclusions: This safe, effective program allowed extension of physical therapy goals in a highly complex patient population during a time of very high demand. Making early mobility a team goal enhanced buy-in, instead of relying exclusively on rehabilitation providers for mobilization. Utilization of the Cannulate, Extubate, Ambulate program may assist other programs to minimize complications of immobility in the ECMO population.

Superiority of bivalirudin over heparin anticoagulation therapy for extracorporeal membrane oxygenation? Too early to draw conclusions

BackgroundWe aimed to compare the efficacy and safety of bivalirudin versus heparin as the anticoagulant in patients undergoing extracorporeal membrane oxygenation (ECMO). MethodsWe conducted a search in PubMed, Embase and the Cochrane Library for all the studies in which bivalirudin was compared to heparin as the anticoagulant for ECMO. Efficacy outcomes were defined as the time to reach therapeutic levels, time within therapeutic range (TTR), thrombotic events, circuit thrombosis, circuit exchanges. Safety outcomes were reported as heparin-induced thrombocytopenia (HIT), major bleeding events, minor bleeding events. Other outcomes included hospital length of stay (LOS), ICU LOS, mortality, 30-day mortality and in-hospital mortality. ResultsTen studies with 1091 patients were included for meta-analysis. A significant reduction in thrombotic events [OR 0.51, 95%CI 0.36,0.73, p = 0.0002, I2 = 0%], major bleeding events [OR 0.31, 95%CI 0.10,0.92, p = 0.04, I2 = 75%] and in-hospital mortality [OR 0.63, 95%CI 0.44,0.89, p = 0.009, I2 = 0%] treated with bivalirudin were found compared with heparin. There were no significant differences between groups regarding the time to reach therapeutic levels [MD 3.53, 95%CI −4.02,11.09, p = 0.36, I2 = 49%], TTR [MD 8.64, 95%CI −1.72,18.65, p = 0.10, I2 = 77%], circuit exchanges [OR 0.92, 95%CI 0.27,3.12, p = 0.90, I2 = 38%], HIT [OR 0.25, 95%CI 0.02,2.52, p = 0.24, I2 = 0%], minor bleeding events [OR 0.93, 95%CI 0.38,2.29, p = 0.87, I2 = 0%], hospital LOS [MD −2.93, 95%CI -9.01,3.15, p = 0.34, I2 = 45%], ICU LOS [MD −4.22, 95%CI -10.07,1.62, p = 0.16, I2 = 0%], mortality [OR 1.84, 95%CI 0.58,5.85, p = 0.30, I2 = 60%] and 30-day mortality [OR 0.75, 95%CI 0.38,1.48, p = 0.41, I2 = 0%]. ConclusionBivalirudin probably be a potential choice for ECMO anticoagulation. However, based on the included studies’ limitation, the superiority of bivalirudin over heparin for anticoagulation in the ECMO population still require further prospective randomized controlled studies before a definite conclusion.

Extracorporeal Membrane Oxygenation and Hemolytic Uremic Syndrome in Children: Outcome Review of a Multicenter National Database

AbstractHemolytic uremic syndrome (HUS) is a triad of hemolytic anemia, thrombocytopenia, and acute renal failure. In critically ill children with HUS, extrarenal manifestations may require intensive care unit admission and extracorporeal membrane oxygenation (ECMO) support. Outcomes specific to HUS and ECMO in children have not been well investigated. The primary aim of this project was to query a multicenter database to identify risk factors associated with mortality in HUS patients supported on ECMO. A secondary aim was to identify factors associated with ECMO utilization in children with HUS. Utilizing the Pediatric Health Information System database (January 2004 and September 2018), this retrospective, multicenter cohort study identified the index HUS hospitalization among children aged 0 to 18 years. Univariate analysis was used to compare demographics, clinical characteristics, and procedures to identify risk factors associated with adverse outcomes. Among 4,144 subjects, 37 were supported on ECMO. Survival for those on ECMO support was 54%. Among nonsurvivors, 59% of deaths occurred within 14 days of hospitalization. The mean hospital LOS was 15.9 days in nonsurvivors versus 53.9 days for survivors (p &lt; 0.001). When comparing subjects supported on ECMO to those who were not, patients with ECMO support had statistically longer hospital LOS and higher rates of extrarenal involvement (p &lt; 0.001). This study found a mortality rate of 46% among HUS patients requiring ECMO. The investigated clinical risk factors were not associated with mortality among the ECMO population. The study identifies risk factors associated with ECMO utilization in children with HUS.

1115: EVALUATION OF BIVALIRUDIN ANTICOAGULATION IN PATIENTS ON ECMO DUE TO COVID-19 RESPIRATORY FAILURE

Introduction: Patients supported on extracorporeal membrane oxygenation (ECMO) due to COVID-19 are at an increased risk of both thromboembolic complications and thrombocytopenia. Bivalirudin, a direct thrombin inhibitor, is increasingly being utilized for anticoagulation in the ECMO patient though there is largely a lack of literature within the COVID-19 population. The objective of our study was to evaluate the safety and efficacy of alternative anticoagulation with bivalirudin in patients on ECMO with COVID-19 respiratory failure. Methods: This was a non-interventional retrospective chart review conducted at a single center large community hospital between January 2020 – November 2021. We included both venovenous (VV) and venoarterial (VA) adult ECMO patients anticoagulated with bivalirudin that tested positive for COVID-19. Patients were excluded if their duration of ECMO cannulation was less than 48 hours. Descriptive statistical analyses were performed utilizing median with interquartile range and frequency with percent as appropriate. Results: Overall, 180 ECMO patients were included in the study. The duration of ECMO cannulation was 29 (9-54) days and our cohort experienced a 42% mortality rate. The rate of thrombotic events including in-circuit thrombosis, arterial and venous thrombotic events was 22%. The median initial platelet count on ECMO was 206 (157-274) and the median nadir was 85 (48-121). ELSO defined major bleeding occurred at a rate of 53% within this cohort. Conclusions: To our knowledge, this study describes the largest number of patients anticoagulated with bivalirudin for ECMO secondary to COVID-19. Our results suggest similar rates of thrombotic events compared to ELSO registry data. While the half-life of bivalirudin is short, clinicians should still be cautious of bleeding due to lack of a specific reversal agent. Retrospective studies with a comparator cohort, as well as randomized trials are warranted to further evaluate the selection of intravenous anticoagulants in the ECMO population with and without COVID-19.

Anti-factor Xa vs aPTT for heparin monitoring in extracorporeal membrane oxygenation.

The goal of this study was to evaluate the correlation of anti-factor Xa (anti-Xa) and activated partial thromboplastin time (aPTT) measures with heparin dosing in adult patients on extracorporeal membrane oxygenation (ECMO) support. This was a retrospective cohort study evaluating adult patients managed on ECMO for at least 24 hours who received unfractionated heparin for systemic anticoagulation and were monitored per protocol using anti-Xa and/or aPTT coagulation assays. The primary outcome was the correlation between aPTT and anti-Xa measures. The secondary outcomes included, but were not limited to, the number of hemorrhagic and thrombotic events. Twenty-seven patients were included in this study. In the 227 events where both laboratory values were collected, a weak correlation was found between anti-Xa and aPTT (Spearman's correlation coefficient = 0.4, P = 0). In the 12 hemorrhagic events that occurred, aPTT was collected for only 10 events. Fifty percent of those events were associated with supratherapeutic aPTT, while none of the hemorrhagic events were associated with a supratherapeutic anti-Xa level. Two thrombotic events occurred, one of which had subtherapeutic anti-Xa and aPTT and the other of which had neither an anti-Xa nor aPTT measure on the day the event occurred. In a population of patients on ECMO, many of whom had coronavirus disease 2019 (COVID-19), there was a weak association between aPTT and anti-Xa measures. Hemorrhagic evens were more common than thrombotic events; however, a relationship between these events and aPTT or anti-Xa levels was not determined. The applicability of these findings to an ECMO population without COVID-19 is unknown and will require further study.

Use of a Calibrated, Drug-Specific DTT Assay to Improve Bivalirudin Monitoring in Pediatric Extracorporeal Membrane Oxygenation (ECMO)

Background: Balancing the hemostatic system in anticoagulated ECMO patients to optimally prevent thrombosis and bleeding is challenging. Although the traditional anticoagulant of choice for ECMO has been unfractionated heparin (UFH), use of the direct thrombin inhibitor bivalirudin is growing, due to reported reductions in bleeding and thrombotic complications. Bivalirudin monitoring remains problematic, as the most widely available and commonly used assay, the activated partial thromboplastin time (aPTT), correlates poorly with other assays of bivalirudin effect. An accurate, standardized monitoring test is needed. In a prior study we investigated use of a research-only dilute thrombin time (dTT) assay calibrated to bivalirudin concentration (Hemoclot, Hyphen-Biomed, FR) in a pediatric ventricular assist device (VAD) population. This bivalirudin dTT had excellent correlation with both the clinical dTT (R2 = 0.991) and with a research-only, drug-calibrated factor IIa chromogenic assay (BiophenDT, Hyphen-Biomed, FR) (R2 = 0.94), but poor correlation with the aPTT (R2 =0.1). This led to an institutional practice change to utilize the clinical dTT and the bivalirudin dTT assay for monitoring bivalirudin in VAD patients. Clinicians started to include these tests as well as the aPTT for patients on ECMO; however, validation of the test in the ECMO population has not been reported. Aim: The aim of this quality improvement project was to validate how the bivalirudin dTT correlated with the clinically ordered dTT (c-dTT) and aPTT in pediatric ECMO patients. Methods: A retrospective review of pediatric ECMO patients ages 0-18 years treated with bivalirudin was conducted. Bivalirudin dosing, monitoring and titration was at the discretion of the treating physician. Clinically ordered laboratory testing of interest included c-dTT, bivalirudin dTT, and aPTT. The bivalirudin dTT uses a known quantity of human thrombin added to a 1:10 diluted plasma sample to initiate clotting. Clotting time (seconds) is related to bivalirudin concentration using drug-specific controls and calibrators of low and high (1.5 and 4 microgram/mL) bivalirudin (Biophen, Hyphen-Biomed, FR). Clinical data is reported descriptively. The bivalirudin dTT was compared to aPTT and c-dTT results using Pearson correlation and an R2 coefficient determined by simple linear regression. Data analysis on clinical outcomes including circuit thrombosis, patient thrombosis, and bleeding events is ongoing. Results: In total, 124 clinically obtained, concurrent c-dTT, aPTT, and bivalirudin dTT results from 6 pediatric ECMO patients receiving bivalirudin were evaluated. Ages ranged from 0-14 years (mean 3.5 years) with 4 patients started on ECMO in the neonatal period (<1 month of age). Indications for ECMO included congenital heart disease, congenital diaphragmatic hernia, respiratory failure, and cardiogenic shock. Mean bivalirudin infusion rate was 0.6 mg/kg/hr (range 0.15-0.84mg/kg/hr). Average duration on bivalirudin was 8 days (range 4-11) for 5 of the 6 patients, with 1 patient on for > 150 days. The mean aPTT was 78.5 seconds (range 55.9-105.5 seconds). The mean c-dTT was 51 seconds (range 25.4-71.1 seconds). The bivalirudin assay had poor correlation with aPTT (R2 = 0.273, Fig 1) and excellent correlation with the c-dTT (R2 = 0.899, Fig 2). A c-dTT range of 35-65 seconds corresponded with a bivalirudin dTT level of 0.55-1.8mcg/mL. Discussion: Here we report results of the clinical use of a bivalirudin dTT monitoring assay in pediatric ECMO patients. Similar to prior results in VADs, the aPTT showed poor correlation with the bivalirudin dTT. The c-dTT had excellent correlation with the bivalirudin dTT and results were so stable for an infusion rate that clinicians ordered less frequent monitoring labs, compared to their practice for UFH. More research and outcomes data is needed to determine the appropriate therapeutic range for optimizing bivalirudin effect and minimizing complications. Validation of a bivalirudin-specific assay that can be used by many institutions will facilitate collaboration on outcomes-based research. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Prevalence and Impact of Infection during Extracorporeal Membrane Oxygenation in Oncologic Patients: A Retrospective Analysis of the Extracorporeal Life Support Organization (ELSO) Registry.

Background: Extracorporeal membrane oxygenation (ECMO) is widely utilized for severe cardiopulmonary insufficiency, but its application to the oncologic population has been debated given concern for increased risk of infection. This study aims to analyze the implications of infections acquired during ECMO runs in patients with malignancy. Methods: The Extracorporeal Life Support Organization (ELSO) database was queried for patients with an International Classification of Diseases code of neoplasms over the last two decades (2000-2019). Culture-proven infections during ECMO runs were analyzed and compared to previously reported data for all ECMO runs. Results: Two thousand, seven hundred and fifty-seven patients met inclusion criteria. Infection acquired during ECMO run was found in 687 patients, a significantly greater proportion compared to all ECMO runs (24.9% vs 11.7%; P = .001). Adult patients had a significantly higher rate of infection (27.0%; P < .001) compared to neonatal (11.0%) and pediatric (21.4%) patients. Prevalence of infection was highest in pulmonary ECMO (29.0%), while the infection rate standardized with ECMO duration was highest in extracorporeal cardiopulmonary resuscitation (55.03/1000-day ECMO run). Compared with ECMO for all diagnoses, the prevalence of Candida and Klebsiella infection was significantly higher in adult and pediatric oncologic patients. Regardless of the pathogen, the presence of infection was not associated with lower survival (38.6% vs 40.0%; P = .522). Conclusions: Oncologic patients had a significantly higher infection rate while on ECMO compared with the general ECMO population. However, the prognostic impact of these infections was minimal, thus ECMO should not be withheld in oncologic patients solely with concern for infection.

Evaluation of anticoagulation with bivalirudin for heparin-induced thrombocytopenia during extracorporeal membrane oxygenation.

Unfractionated heparin is the most commonly utilized anticoagulant in extracorporeal membrane oxygenation (ECMO) due to clinician familiarity, ease of reversal, and low cost compared to alternative agents. However, heparin's anticoagulant effect can be unpredictable and its use accompanies a risk of heparin induced thrombocytopenia (HIT). Successful use of bivalirudin as an alternative to heparin in non-HIT ECMO patients has previously been described. However, there is a paucity of data regarding its utilization in patients with confirmed HIT on ECMO. This single-center retrospective chart review at Cleveland Clinic Main Campus included 12 ECMO patients who were managed with bivalirudin for a new diagnosis of HIT. Descriptive statistical analyses were performed utilizing median with interquartile range and number with percent as appropriate. Of the 12 patients included, median ECMO duration was 328.5 (218.8-502.1) h and venoarterial ECMO was the most common configuration. No patients experienced the primary outcome of in-circuit thrombosis while on bivalirudin. One patient developed a deep vein thrombosis 22.5 h after switching from heparin to bivalirudin. Major bleeding occurred during bivalirudin therapy in 8 (66.7%) patients. Overall, our study results suggest that bivalirudin is effective for the management of HIT and did not show evidence of in-circuit thrombosis. A high incidence of major bleeding was observed with bivalirudin use within this study. Clinicians should view bivalirudin as an acceptable agent for the treatment of HIT in the ECMO population, but must consider bleeding risk given the lack of effective reversal agents.

Intensive Care Unit-Acquired Weakness in Patients With Extracorporeal Membrane Oxygenation Support: Frequency and Clinical Characteristics.

BackgroundIntensive care unit-acquired weakness (ICU-AW) is common in critical illness patients and is well described. Extracorporeal membrane oxygenation (ECMO) is used as a life-saving method and patients with ECMO support often suffer more risk factors of ICU-AW. However, information on the frequency and clinical characteristics of ICU-AW in patients with ECMO support is lacking. Our study aims to clarify the frequency and characteristics of ICU-AW in ECMO patients.MethodsWe conducted a retrospective study, ICU-AW was diagnosed when patients were discharged with a Medical Research Council (MRC) sum score <48. Clinical information was collected from the case report forms. Univariable analysis, LASSO regression analysis, and logistic regression analysis were used to analyze the clinical data of individuals.ResultsIn ECMO population, 40 (80%) patients diagnosed with ICU-AW. On univariable analysis, the ICU-AW group had higher Acute Physiology and Chronic Health Evaluation II (APACHE II) [13.9 (6.5–21.3) versus 21.1 (14.3–27.9), p = 0.005], longer deep sedation time [2 (0–7) versus 6.5 (3–11), p = 0.005], longer mechanical ventilation time [6.8 (2.6–9.3) versus 14.3 (6.6–19.3), p = 0.008], lower lowest albumin [26.7 (23.8–29.5) versus 22.1 (18.5–25.7), p < 0.001]. The LASSO analysis showed mechanical ventilation time, deep sedation time, deep sedation time during ECMO operation, APACHE II, and lowest albumin level were independent predictors of ICU-AW. To investigate whether ICU-AW occurs more frequently in the ECMO population, we performed a 1:1 matching with patients without ECMO and found there was no difference in the incidence of ICU-AW between the two groups. Logistic regression analysis of combined cohorts showed lowest albumin odds ratio (OR: 1.9, p = 0.024), deep sedation time (OR: 1.9, p = 0.022), mechanical ventilation time (OR: 2.0, p = 0.034), and APACHE II (OR: 2.3, p = 0.034) were independent risk factors of ICU-AW, but not ECMO.ConclusionThe ICU-AW was common with a prevalence of 80% in the ECMO population. Mechanical ventilation time, deep sedation time, deep sedation time during ECMO operation, APACHE II, and lowest albumin level were risk factors of ICU-AW in ECMO population. The ECMO wasn’t an independent risk factor of ICU-AW.

Viscoelastic Testing in Pediatric Mechanical Circulatory Support.

Pediatric mechanical circulatory support can be lifesaving. However, managing anticoagulation is one of the most challenging aspects of care in patients requiring mechanical circulatory support. Effective anticoagulation is even more difficult in pediatric patients due to the smaller size of their blood vessels, increased turbulent flow, and developmental hemostasis. Recently, viscoelastic testing (VET) has been used as a qualitative measure of anticoagulation efficacy in patients receiving extracorporeal membrane oxygenation (ECMO) and ventricular assist devices (VAD). Thromboelastography (TEG®) and thromboelastometry (ROTEM®) provide a global qualitative assessment of hemostatic function from initiation of clot formation with the platelet-fibrin interaction, platelet aggregation, clot strength, and clot lysis. This review focuses on the TEG®/ROTEM® and important laboratory and patient considerations for interpretation in the ECMO and VAD population. We summarize the adult and pediatric ECMO/VAD literature regarding VET values, VET-platelet mapping, utility over standard laboratory monitoring, and association with outcome measures such as blood product utilization, bleeding, and thrombosis.

Evaluation of Severity of Illness Scores in the Pediatric ECMO Population.

Though commonly used for adjustment of risk, severity of illness and mortality risk prediction scores, based on the first 24 h of intensive care unit (ICU) admission, have not been validated in the pediatric extracorporeal membrane oxygenation (ECMO) population. We aimed to determine the association of Pediatric Index of Mortality 2 (PIM2), Pediatric Risk of Mortality Score III (PRISM III) and Pediatric Logistic Organ Dysfunction (PELOD) scores with mortality in pediatric patients on ECMO. This was a retrospective cohort study of children ≤18 years of age included in the Pediatric ECMO Outcomes Registry (PEDECOR) from 2014 to 2018. Logistic regression and Receiver Operating Characteristics (ROC) curves were used to calculate the area under the curve (AUC) to evaluate association of mortality with the scores. Of the 655 cases, 289 (44.1%) did not survive until hospital discharge. AUCs for PIM2, PRISM III, and PELOD predicting mortality were 0.52, 0.52, and 0.51 respectively. PIM2, PRISM III, and PELOD scores are not associated with odds of mortality for pediatric patients receiving ECMO. These scores for a general pediatric ICU population should not be used for prognostication or risk stratification of a select population such as ECMO patients.

Surgical outcomes and complications of bedside tracheostomy in the ICU for patients on ECMO.

Extracorporeal membrane oxygenation (ECMO) is increasingly employed in the management of patients with severe cardiac and pulmonary dysfunction. Patients commonly require tracheostomy for ventilator liberation. Though bedside percutaneous tracheostomy is commonly performed, it has the potential for increased complications, both surgical and with the ECMO circuit. We examined surgical outcomes of bedside percutaneous tracheostomy in the ECMO population. Patients were identified from an institutional database for bedside procedures. Demographics and data on complications were recorded. Descriptive statistics were calculated. 37 patients on ECMO at the time of tracheostomy were identified. Median age and BMI were 43.2 and 28.0, respectively. 33 patients (89%) were on VV ECMO, and 4 (11%) were on VA ECMO. All were on anticoagulation prior to tracheostomy, which was held for 4 h before and after the procedure in all cases. There were no procedure-related deaths or airway losses. No patients experienced periprocedural clotting events of their ECMO circuit or oxygenator within 24 h. 3 patients (8%) required reintervention (re-exploration or bronchoscopy) for bleeding. Four other patients (10%) had minor bleeding controlled with packing. One patient had pneumomediastinum which resolved without intervention, and one had an occlusion of their tracheostomy which was treated with tracheostomy exchange. Bedside percutaneous tracheostomy is feasible for patients on ECMO. Further study is needed to determine specific risk factors for complications and means to mitigate these. Bedside percutaneous tracheostomy may be considered as part of the management of patients on ECMO to help facilitate liberation from mechanical support.

EARLY CONTINUOUS RENAL REPLACEMENT THERAPY FOR VOLUME MANAGEMENT WITHOUT SIGNIFICANT KIDNEY INJURY DURING EXTRACORPOREAL MEMBRANE OXYGENATION

SESSION TITLE: Critical Care Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Volume overload is linked to higher mortality in extracorporeal membrane oxygenation (ECMO) patients. Correspondingly, early and aggressive volume management has been associated with improved survival. Data on continuous renal replacement therapy (CRRT) specifically for volume removal in the adult ECMO population is deficient. The purpose of this study was to evaluate the efficacy of early CRRT primarily for volume removal in ECMO patients with mild or no kidney injury. METHODS: A single center, retrospective chart review was conducted for ECMO patients over a 9-year period. ECMO patients with mild or no kidney injury who received CRRT for volume removal were compared to like patients who did not receive CRRT. Intergroup statistical comparisons were performed using Wilcoxon/Kruskal-Wallis and chi-square tests. RESULTS: 140 ECMO patient charts were reviewed. 74 patients received CRRT. Of these, 19 patients had no or stage 1 acute kidney injury as defined by Kidney Disease Improving Global Outcomes (KDIGO). For comparison, 19 non-CRRT patients were propensity matched for age, gender, and ECMO mode. We reviewed multiple variables with the primary focus being fluid balance at 72-hours post CRRT initiation and survival at discharge. We found a significant difference in fluid balance in the two cohorts. The CRRT group had an average fluid balance of -3840 ml while the non-CRRT group had a net balance of 425 ml for a similar period. CONCLUSIONS: The use of early CRRT for volume management in ECMO patients with minimal or no kidney injury achieved a negative fluid balance that was substantially negative and significantly lower than patients without CRRT. CLINICAL IMPLICATIONS: Aggressive fluid management is a vital aspect of ECMO care. Our findings suggest that early CRRT in ECMO patients without significant kidney injury can achieve a considerable negative fluid balance. DISCLOSURES: No relevant relationships by Jason Thomas, source=Web Response

Tau Is Elevated in Pediatric Patients on Extracorporeal Membrane Oxygenation.

Neurologic injury is a known and feared complication of extracorporeal membrane oxygenation (ECMO). Neurologic biomarkers may have a role in assisting in early identification of such. Axonal biomarker tau has not been investigated in the pediatric ECMO population. The objective of this study is to evaluate plasma levels of tau in pediatric patients supported with ECMO. Eighteen patients requiring ECMO support in a quaternary pediatric intensive care unit at a university-affiliated children's hospital from October 2015 to February 2017 were enrolled. Patients undergoing extracorporeal cardiopulmonary resuscitation or recent history of bypass were excluded. Plasma tau was measured using enzyme-linked immunosorbent assay. Neuroimaging was reviewed for acute neurologic injury, and tau levels were analyzed to assess for correlation. Tau was significantly higher in ECMO patients than in control subjects. Sixty-one percent of subjects had evidence of acute brain injury on neuroimaging, but tau level did not correlate with injury. Subjects with multifocal injury all experienced infarction and had significantly higher tau levels on ECMO day 3 than patients with isolated injury. In addition, peak tau levels of neuro-injured subjects were compared with controls and noninjured ECMO subjects using receiver operating curve analysis. This study demonstrates preliminary evidence of axonal injury in pediatric ECMO patients.

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

Extracorporeal membrane oxygenation has been widely used after paediatric cardiac surgery due to increasing complex surgical repairs in neonates and infants having complex CHDs. We reviewed retrospectively the medical records of all patients with CHD requiring corrective or palliative cardiac surgery at King Abdulaziz University Hospital that needed extracorporeal membrane oxygenation support between November 2015 and November 2018. The extracorporeal membrane oxygenation population was 30 patients, which represented 4% of 746 children who had cardiac surgery during this period. The patients' age range was from 1 day to 20.33 years, with a median age of 6.5 months. Median weight was 5 kg (range from 2 to 53 kg). Twenty patients were successfully decannulated (66.67%), and 12 patients (40%) were survived to hospital discharge. Patients with biventricular repair tended to have better survival rate compared with those with single ventricle palliation (55.55 versus 16.66%, p-value 0.058). During the first 24 hours of extracorporeal membrane oxygenation support, the flow rate was significantly reduced after 4 hours of extracorporeal membrane oxygenation connection in successfully decannulated patients. Survival to hospital discharge in patients requiring extracorporeal membrane oxygenation support after paediatric cardiac surgery was better in those who underwent biventricular repair than in those who had univentricular palliation. Capillary leak on extracorporeal membrane oxygenation could be a risk of mortality in patients after paediatric cardiac surgery.

Anticoagulation in Neonatal ECMO: An Enigma Despite a Lot of Effort!

Extracorporeal membrane oxygenation (ECMO) is a valuable modality used to support neonates, children, and adults with cardiorespiratory failure refractory to conventional therapy. It requires use of anticoagulation to prevent clotting in the extracorporeal circuit. Balancing bleeding from excessive anticoagulation with thrombotic risk remains a difficult aspect of ECMO care. Despite many advances in ECMO technology, better understanding of the coagulation cascade and new monitoring schemes to adjust anticoagulation, bleeding and thrombosis remain the most frequent complications in ECMO and are associated with morbidity and mortality. In neonates, ECMO is also complicated by the immature hemostatic system, laboratory testing norms which are not specific for neonates, lack of uniformity in management, and paucity of high-quality evidence to determine best practices. Traditional anticoagulation focuses on the use of unfractionated heparin. Direct thrombin inhibitors are also used but have not been well-studied in the neonatal ECMO population. Anticoagulation monitoring is complex and currently available assays do not take into account thrombin generation or platelet contribution to clot formation. Global assays may add valuable information to guide therapy. This review provides an overview of hemostatic alterations, anticoagulation, monitoring and management, novel anticoagulant use, and circuit modifications for neonatal ECMO. Future considerations are also presented.

Pediatric ECMO Research: The Case for Collaboration.

The use of extracorporeal membrane oxygenation (ECMO) in the pediatric age has increased considerably in the last decade, as has the complexity of cases and the variety of indications outside of the neonatal age. However, no randomized controlled trials have been attempted to date to test ECMO as an intervention in non-neonatal pediatric patients with critical illness. In this review, we provide a brief overview of the history of clinical research in pediatric ECMO and discuss methodological challenges including heterogeneity of ages and diagnoses in the pediatric ECMO population, rapid advances in technology and clinical practice related to ECMO, feasibility of enrolling critically ill children on ECMO in clinical research studies, and variability in ECMO management across institutions and countries. Lastly, we discuss opportunities and existing infrastructure for future multicenter, multi-network research collaborations for pediatric ECMO studies.