Extracorporeal Membrane Oxygenation Patients Research Articles

Abstract 4137942: Comparing Outcomes in Low versus High Activated Partial Thromboplastin Time-guided Anticoagulation Monitoring during Extracorporeal Membrane Oxygenation

Introduction: Systemic anticoagulation in Extracorporeal Membrane Oxygenation (ECMO) aims to reduce the risk of patient and circuit thrombosis, but requires monitoring due to risk of bleeding. Activated partial thromboplastin time (aPTT) is one of many tests utilized for this purpose. However, it lacks validation in ECMO patients and its clinical utility necessitates further analysis. Aim: We aim to elucidate associations between low versus high aPTT-guided anticoagulation monitoring and total time, survival, bleeding, and thrombotic events during ECMO. Methods: A retrospective review was conducted on 93 patients requiring ECMO at our institution between January 2020 and March 2021. Study inclusion required more than 2 days on ECMO and maintenance on anticoagulation with aPTT targets predominantly greater (>) or less than (<) 60 seconds (s). Final cohort was 74 subjects; 30 subjects with majority aPTT targets <60s composed the control “low” aPTT group and 44 subjects with aPTT targets >60s composed the “high” aPTT group. Primary outcomes were survival to decannulation, survival to discharge, average time on ECMO, and incidence of bleeding and thrombotic events during ECMO. Bleeding and thrombotic events were classified into subtypes and incidence of each was recorded. Statistical analyses were performed with Fisher’s exact, Pearson’s chi-square, and Student’s t-tests with an alpha level of .05 on IBM SPSS software. Results: The high group required a longer average time on ECMO (29.5 days versus 14.3 days; p = .002; 95% CI [5.5; 24.7]). Chi-square tests did not show an association between the low versus high groups and survival to decannulation (22/30 and 35/44; p = .533), survival to hospital discharge (17/30 and 30/44; p = .312), or overall incidence of bleeding (18/30 and 20/44; p = .219) and thrombotic events (7/30 and 14/44; p = .427). Regarding subtypes of events, Fisher’s exact test showed an association between aPTT target >60s and severe epistaxis (1/30 in the low and 9/44 in the high group; two-tailed p = .042). Though not significant, a greater incidence of oxygenator failure and circuit thrombosis was recorded in the high group. Conclusions: Our findings did not establish a relationship between aPTT target <60s or >60s and survival, bleeding, or thrombotic events. However, aPTT target >60s was associated with longer average ECMO time and severe epistaxis. Further investigation of aPTT-guided anticoagulation monitoring in ECMO patients is needed.

An investigation into the contributing factors to survival of ARDS patients supported by veno-venous ECMO.

This study aimed to identify characteristics associated with survival during and post Extra Corporeal Membrane Oxygenation (ECMO) therapy, in patients with acute respiratory distress syndrome (ARDS) during the COVID-19 pandemic. A retrospective observational study on 94 consecutive patients with confirmed COVID-19 induced ARDS supported by ECMO was carried out 49/94 (52.7%) patients survived to hospital discharge. Non-survivors were found to have significantly (p < .05) higher: Pre-ECMO International normalized ratios (INR), carbon dioxide partial pressure (pCO2), Acute Kidney Injury (AKI) scores and blood urea levels. Also, lower pre-ECMO peak inspiratory pressures (PIP), mean arterial pressure, saturation of arterial oxygen (SaO2), blood bicarbonate levels (HCO3), blood Ph and fewer trials off ECMO with shorter combined trial off times. Patients that did not survive were more likely to have renal impairment and have received peri-ECMO haemofiltration. Poor prognosis was significantly associated with: receiving pre-ECMO nitric oxide (HR = 3.047, CI = 1.247-7.447, p = .015), renal impairment (HR = 3.023, CI = 1.586-5.763, p < .001), AKI of 2 (HR = 3.611, CI = 1.382-9.441, p = .009) or 3 (HR = 3.275, CI = 1.235-8.685, p = .017), peri-ECMO haemofiltration (HR = 2.412, CI = 1.310-4.442, p = .005) and the ABO blood group B (HR = 3.103, CI = 1.335-7.212, p = .008). pre-ECMO high CO2 (HR = 1.134, CI = 1.031-1.248, p = .010), blood lactate (HR = 1.350, CI = 1.156-1.576, p < .001), INR (HR = 2.571, CI = 1.438-4.598, p=<0.001) and lower blood Ph (HR = 0.023, CI = 0.002-0.210, p < .001). Commonly used mortality scores may not be of use in a COVID-19 cohort of ECMO patients. The initiation of ECMO needs to be implemented prior to metabolic derangements, renal and fulminant respiratory failure.

Wavelet and time-based cerebral autoregulation analysis using diffuse correlation spectroscopy on adults undergoing extracorporeal membrane oxygenation therapy.

Adult patients who have suffered acute cardiac or pulmonary failure are increasingly being treated using extracorporeal membrane oxygenation (ECMO), a cardiopulmonary bypass technique. While ECMO has improved the long-term outcomes of these patients, neurological injuries can occur from underlying illness or ECMO itself. Cerebral autoregulation (CA) allows the brain to maintain steady perfusion during changes in systemic blood pressure. Dysfunctional CA is a marker of acute brain injury and can worsen neurologic damage. Monitoring CA using invasive modalities can be risky in ECMO patients due to the necessity of anticoagulation therapy. Diffuse correlation spectroscopy (DCS) measures cerebral blood flow continuously, noninvasively, at the bedside, and can monitor CA. In this study, we compare DCS-based markers of CA in veno-arterial ECMO patients with and without acute brain injury. Adults undergoing ECMO were prospectively enrolled at a single tertiary hospital and underwent DCS and arterial blood pressure monitoring during ECMO. Neurologic injuries were identified using brain computerized tomography (CT) scans obtained in all patients. CA was calculated over a twenty-minute window via wavelet coherence analysis (WCA) over 0.05 Hz to 0.1 Hz and a Pearson correlation (DCSx) between cerebral blood flow measured by DCS and mean arterial pressure. Eleven ECMO patients who received CT neuroimaging were recruited. 5 (45%) patients were found to have neurologic injury. CA indices WCOH, the area under the curve of the WCA, were significantly higher for patients with neurological injuries compared to those without neurological injuries (right hemisphere p = 0.041, left hemisphere p = 0.041). %DCSx, percentage of time DCSx was above a threshold 0.4, were not significantly higher (right hemisphere p = 0.268, left hemisphere p = 0.073). DCS can be used to detect differences in CA for ECMO patients with neurological injuries compared to uninjured patients using WCA.

Utilization and outcomes of extracorporeal membrane oxygenation in patients with cirrhosis

Utilization and outcomes of extracorporeal membrane oxygenation in patients with cirrhosis

Utility of venoarterial extracorporeal membrane oxygenation in patients with acute myocardial infarction complicated by cardiogenic shock

Abstract Background Acute myocardial infarction complicated by cardiogenic shock (AMI-CS) continues to portend poor clinical prognosis and remains a major cause of morbidity and mortality. Although venoarterial (VA) extracorporeal membrane oxygenation (ECMO) is frequently used in the treatment of AMI-CS, studies evaluating its benefit compared to percutaneous ventricular assist devices (pVAD) or standard medical therapy in this patient population have yielded conflicting results. Purpose The goal of this meta-analysis is to evaluate the use of ECMO compared to either pVAD or medical therapy with or without intra-aortic balloon counterpulsation (IABP) in patients presenting with AMI-CS. Methods A database search was performed for studies reporting on the association of ECMO compared to pVAD or medical therapy with or without IABP with clinical outcomes in patients with AMI-CS. The endpoints of interest were 30-day all-cause mortality and long term all-cause mortality. The databases searched included Pubmed, Web of Science, and Embase. The search was not restricted by time or publication status. Registry studies were excluded from this analysis. Results A total of 8 studies with 937 participants (447 treated with ECMO, 243 treated with pVAD, 247 treated with medical therapy with or without IABP) met inclusion criteria. Mean age was 63 years old, 80.5% were men, mean left ventricular ejection fraction was 26%, mean follow-up was 6.3 months (ranging 1-12 months). Treatment of AMI-CS patients with ECMO was not associated with lower risk of 30-day all-cause mortality compared to pVAD or standard medical therapy with or without IABP placement (OR 1.29, 95% CI 0.87-1.90; p=0.21; OR 0.58, 95% CI 0.25-1.35; p=0.13). Heterogenetic was low to moderate for each subgroup. Test for subgroup differences did not demonstrate statistically significant differences in the results for pVAD and for standard medical therapy with or without IABP (p=0.10, I2=64.1%). Compared to pVAD, ECMO was not associated lower risk of long-term mortality (OR 1.27, 95% CI 0.85-1.90; p=0.24). The heterogeneity for this analysis was low (I2=0%). Conclusion In patients presenting with AMI-CS, use of VA-ECMO is not associated with lower risk of mortality compared to pVAD or standard medical therapy with or without IABP placement. The risks and benefits of ECMO should be carefully considered compared to other forms of temporary mechanical circulatory support.Figure 1

Mixed venous to arterial pCO2-gap is poorly correlated to cardiac index in 1526 pulmonary artery catheter monitored critically ill patients

Abstract Background The CO2 gap is the difference between mixed venous and arterial CO2, and can be estimated by the difference in partial pressure in CO2 (Pv-aCO2 or ∆PCO2). ∆PCO2 is affected by cardiac output (CO), CO2 production and solubility. The central venous-to-arterial CO2 gap has been proposed as a less invasive surrogate for P(v-a)CO2 and has been investigated as a measure of adequacy of resuscitation, and to guide sepsis management. Nevertheless, the CO2-gap as determinant of CO has never been thoroughly investigated in large cohort of critically ill ICU-patients. This study aims to investigate the relationship between ∆PCO2 and cardiac index (CI) in a retrospective cohort of critically ill patients in a large quaternary cardiothoracic intensive care unit. Methods Over 62 months, pulmonary artery catheter monitored critically ill patients were identified and their case files reviewed in retrospect. Extracorporeal membrane oxygenation (ECMO) patients were excluded. P(v-a)CO2 measurements were defined as mixed venous and arterial pCO2 measurements drawn simultaneously or within maximum 30 minutes together with PA-measurements. Correlation coefficients were calculated between P(v-a)CO2 and CI, serum lactate, mixed venous saturations (SvO2), cardiac power index (CPI), inotropic score (IS), central venous pressure (CVP) and minute expiratory volume (MV)(Table 1). We used receiver operator characteristic (ROC) curves to assess the diagnostic performance of P(v-a)CO2 as a surrogate for CI lower than 2,2L/min/m2. Multivariate linear regression analysis was performed with P(v-a)CO2 as an dependent variable. Results 4414 P(v-a)CO2 measurements were identified from 1526 patients. Median P(v-a)CO2 was 0,86 kPa (0,66-1,1) or 6.45 mmHg (4.95-8.25), and mean CI was 2.7l/min/m2 (2.2-3.2). Correlation coefficients of P(v-a)CO2 with the other variables remained poor (&amp;gt; 0,35). The area under the ROC curve for P(v-a)CO2 as a predictor of CI&amp;lt;2.2l/min/m2 was 0.65, p&amp;lt;0.0001 (Fig. 1B). A value of P(v-a)CO2 &amp;gt; 6.9 mmHg was found to have the highest sensitivity and specificity, with a poor performance of 61.21% sensitivity and 62.73% specificity. Conclusion This large retrospective study in 1526 critically ill cardiac ICU-patients did not demonstrate a strong relationship between P(v-a)CO2 and CI, nor with any other hemodynamic variable found in the ICU patient cohort studied (Table 1). This raises scepticism regarding the efficacy of P(v-a)CO2 as a physiological goal in guiding resuscitation and management of this precarious patient group. Therefore, we argue that the PA-catheter remains the cornerstone in assessing critically ill (cardiothoracic) ICU patients.

Neurosurgical Procedures in Patients Requiring Extracorporeal Membrane Oxygenation.

Extracorporeal membrane oxygenation (ECMO) is often withheld in patients with significant neurologic injury or recent neurosurgical intervention due to perceived futility. Studies of neurosurgical interventions before or during ECMO are limited to case reports or single-center series, limiting generalizability, and outcomes in this population are unknown. We therefore sought to report the outcomes of ECMO patients with acute neurosurgical interventions at four high-volume ECMO and comprehensive stroke centers. Retrospective case series. Four academic tertiary referral hospitals in the United States. Adults (n = 24) having undergone neurosurgical procedures before or during ECMO. None. We retrospectively reviewed adults at four institutions who had undergone neurosurgical procedures immediately before or during ECMO from 2015 to 2023. The primary outcome was survival to hospital discharge. Secondary outcomes included favorable neurologic outcome (Cerebral Performance Category 1 or 2) and neurosurgical complications. Twenty-four of 2957 ECMO patients (0.8%) were included. Primary indications for neurosurgical intervention included traumatic brain (n = 8) or spinal (n = 3) injury, spontaneous intracranial hemorrhage (n = 6), and acute ischemic stroke (n = 5). Procedures included extraventricular drain (EVD) and/or intracranial pressure monitor placement (n = 10), craniectomy/craniotomy (n = 5), endovascular thrombectomy (n = 4), and spinal surgery (n = 3). Fifteen patients (63%) survived to hospital discharge, of whom 12 (80%) were discharged with favorable neurologic outcomes. Survival to discharge was similar for venoarterial and venovenous ECMO patients (8/12 vs. 7/12; p = 0.67) and those who had neurosurgery before vs. during ECMO (8/13 vs. 7/11; p = 0.92). One patient (4%) experienced a neurosurgical complication, a nonlethal tract hemorrhage from EVD placement. Survival to discharge was similar for neurosurgical and nonneurosurgical ECMO patients at participating institutions (63% vs. 57%; p = 0.58). Patients with acute neurologic injury can feasibly undergo neurosurgery during ECMO or can undergo ECMO after recent neurosurgery. Larger studies are needed to fully understand risks for bleeding and other procedure-related complications.

Ultra-Low-Field Portable MRI and Extracorporeal Membrane Oxygenation: Preclinical Safety Testing.

Conventional MRI is incompatible with extracorporeal membrane oxygenation (ECMO) cannulas and pumps. Ultra-low-field portable MRI (ULF-pMRI) with 0.064 Tesla may provide a solution, but its safety and compatibility is unknown. ULF-pMRI does not cause significant displacement and heating of ECMO cannulas and does not affect ECMO pump function. ECMO cannulas in various sizes were tested ex vivo using phantom models to assess displacement force and heating according to the American Society for Testing and Materials criteria. ECMO pump function was assessed by pump flow and power consumption. In vivo studies involved five female domestic pigs (20-42 kg) undergoing different ECMO configurations (peripheral and central cannulation) and types of cannulas with an imaging protocol consisting of T2-weighted, T1-weighted, FLuid-Attenuated Inversion Recovery, and diffusion-weighted imaging sequences. Phantom models demonstrated that ECMO cannulas, both single lumen with various sizes (15-24-Fr) and double lumen cannula, had average displacement force less than gravitational force within 5 gauss safety line of ULF-pMRI and temperature changes less than 1°C over 15 minutes of scanning and ECMO pump maintained stable flow and power consumption immediately outside of the 5 gauss line. All pig models showed no visible motion due to displacement force or heating of the cannulas. ECMO flow and the animals' hemodynamic status maintained stability, with no changes greater than 10%, respectively. ULF-pMRI is safe and feasible for use with standard ECMO configurations, supporting its clinical application as a neuroimaging modality in ECMO patients.

Effect of Unfractionated Heparin Dose on Complement Activation and Selected Extracellular Vesicle Populations during Extracorporeal Membrane Oxygenation.

Extracorporeal membrane oxygenation (ECMO) provides critical support for patients with severe cardiopulmonary dysfunction. Unfractionated heparin (UFH) is used for anticoagulation to maintain circuit patency and avoid thrombotic complications, but it increases the risk of bleeding. Extracellular vesicles (EVs), nano-sized subcellular spheres with potential pro-coagulant properties, are released during cellular stress and may serve as potential targets for monitoring anticoagulation, particularly in thromboinflammation. We investigated the impact of UFH dose during ECMO therapy at the coagulation-inflammation interface level, focusing on complement activation and changes in circulating large EV (lEV) subsets. In a post hoc analysis of a multicenter randomized controlled trial comparing two anticoagulation management algorithms, we examined lEV levels and complement activation in 23 veno-venous-ECMO patients stratified by UFH dose. Blood samples were collected at different time points and grouped into three phases of ECMO therapy: initiation (day 1), mid (days 3-4), and late (days 6-7). Immunoassays detected complement activation, and flow cytometry analyzed lEV populations with an emphasis on mitochondria-carrying subsets. Patients receiving <15 IU/kg/h UFH exhibited higher levels of the complement activation product C5a and soluble terminal complement complex (sC5b-9). Lower UFH doses were linked to increased endothelial-derived lEVs, while higher doses were associated with elevated RBC-derived and mitochondria-positive lEVs. Our findings suggest the potential theranostic relevance of EV detection at the coagulation-inflammation interface. Further research is needed to standardize EV detection methods and validate these findings in larger ECMO patient cohorts.

Extracorporeal membrane oxygenation: unmet needs and perspectives.

Extracorporeal Membrane Oxygenation (ECMO) has become an essential lifesaving intervention for individuals with severe cardiovascular and respiratory failure. Its application is expanding across several therapeutic contexts, surpassing conventional indications. The COVID-19 pandemic has significantly stressed worldwide health systems to manage acute respiratory failure. ECMO has been employed as a vital intervention, particularly for patients with severe COVID-19-induced acute respiratory distress syndrome (ARDS). ECMO is applicable throughout pregnancy. The principal indications for ECMO in pregnant women align with those in the general population. However, pregnancy complicates issues, necessitating consideration of both mother's and infant's well-being. Patients with systemic rheumatic diseases are prone to experience life-threatening complications. While a majority of these patients respond to immunosuppressive drugs, a small percentage suffer organ failure and may benefit from ECMO as a bridge to recovery. The article addresses coagulation therapies, highlighting the necessity of precise anticoagulation to avert both bleeding and thrombosis, particularly in patients requiring extended ECMO support. Additionally, the pharmacokinetics of antibiotics in ECMO patients are summarized, including the influence of the ECMO circuit on drug metabolism. Survey-based research offers valuable insights into ECMO use, procedures, and challenges. The paper evaluates current survey-based research and ECMO guidelines, highlighting clinical practice, training, and resource availability discrepancies across ECMO centers globally. Particular focus is placed on the rehabilitation requirements of ECMO survivors, acknowledging the importance of early mobilization and post-discharge care in improving long-term outcomes and quality of life.

Acute Ischemic Stroke during Extracorporeal Membrane Oxygenation (ECMO): A Narrative Review of the Literature

Ischemic stroke (IS) is a severe complication and leading cause of mortality in patients under extracorporeal membrane oxygenation (ECMO). The aim of our narrative review is to summarize the existing evidence and provide a deep examination of the diagnosis and treatment of acute ischemic stroke patients undergoing ECMO support. The incidence rate of ISs is estimated to be between 1 and 8%, while the mortality rate ranges from 44 to 76%, depending on several factors, including ECMO type, duration of support and patient characteristics. Several mechanisms leading to ISs during ECMO have been identified, with thromboembolic events and cerebral hypoperfusion being the most common causes. However, considering that most of the ECMO patients are severely ill or under sedation, stroke symptoms are often underdiagnosed. Multimodal monitoring and daily clinical assessment could be useful preventive techniques. Early recognition of neurological deficits is of paramount importance for prompt therapeutic interventions. All ECMO patients with suspected strokes should immediately receive brain computed tomography (CT) and CT angiography (CTA) for the identification of large vessel occlusion (LVO) and assessment of collateral blood flow. CT perfusion (CTP) can further assist in the detection of viable tissue (penumbra), especially in cases of strokes of unknown onset. Catheter angiography is required to confirm LVO detected on CTA. Intravenous thrombolytic therapy is usually contraindicated in ECMO as most patients are on active anticoagulation treatment. Therefore, mechanical thrombectomy is the preferred treatment option in cases where there is evidence of LVO. The choice of the arterial vascular access used to perform mechanical thrombectomy should be discussed between interventional radiologists and an ECMO team. Anticoagulation management during the acute phase of IS should be individualized after the thromboembolic risk has been carefully balanced against hemorrhagic risk. A multidisciplinary approach is essential for the optimal management of ISs in patients treated with ECMO.

Neurological monitoring and management for adult extracorporeal membrane oxygenation patients: Extracorporeal Life Support Organization consensus guidelines

Background Critical care of patients on extracorporeal membrane oxygenation (ECMO) with acute brain injury (ABI) is notable for a lack of high-quality clinical evidence. Here, we offer guidelines for neurological care (neurological monitoring and management) of adults during and after ECMO support. Methods These guidelines are based on clinical practice consensus recommendations and scientific statements. We convened an international multidisciplinary consensus panel including 30 clinician-scientists with expertise in ECMO from all chapters of the Extracorporeal Life Support Organization (ELSO). We used a modified Delphi process with three rounds of voting and asked panelists to assess the recommendation levels. Results We identified five key clinical areas needing guidance: (1) neurological monitoring, (2) post-cannulation early physiological targets and ABI, (3) neurological therapy including medical and surgical intervention, (4) neurological prognostication, and (5) neurological follow-up and outcomes. The consensus produced 30 statements and recommendations regarding key clinical areas. We identified several knowledge gaps to shape future research efforts. Conclusions The impact of ABI on morbidity and mortality in ECMO patients is significant. Particularly, early detection and timely intervention are crucial for improving outcomes. These consensus recommendations and scientific statements serve to guide the neurological monitoring and prevention of ABI, and management strategy of ECMO-associated ABI.

A safety comparison of heparin and argatroban anticoagulation in veno-venous extracorporeal membrane oxygenation with a focus on bleeding.

Anticoagulation during extracorporeal membrane oxygenation (ECMO) might still lead to severe bleeding complications. Heparin is the most frequently used anticoagulant, but novel drugs could be promising. Argatroban is a new alternative to heparin. To date, no robust studies have confirmed the clear superiority of argatroban (AG) over heparin, although it has some advantages and may be safer. An observational study was conducted in all adult veno-venous ECMO patients with COVID-19-associated acute respiratory distress syndrome admitted to the University Hospital Ostrava (n = 63). They were anticoagulated with heparin in the first period and with AG in the second period, targeting the same activated partial thromboplastin time (aPTT; 45-60 s). Bleeding complications requiring transfusion and life-threatening bleeding events were evaluated. The primary objective was to compare heparin and AG in terms of bleeding, transfusion requirements and mortality-related bleeding. The total time on ECMO per patient was 16 days with an in-hospital mortality of 55.6%. The red blood cell consumption in the AG group (median 2.7 transfusions/week) was significantly lower than in the heparin group (median 4.2 transfusions/week, p = 0.011). Life-threatening bleeding complications were higher in the heparin group compared to the AG group (35.7% vs. 10.2%, p = 0.035), and mortality-related bleeding complications were also higher in the heparin group (21.4% vs. 2.0%, p = 0.032). Argatroban is an interesting alternative to heparin with less bleeding, less need for red blood cell transfusions and improved safety of ECMO with less mortality-related bleeding.

Intravenous enoxaparin guided by anti-Xa in venovenous extracorporeal membrane oxygenation: A retrospective, single-center study.

Unfractionated heparin is used as the most common anticoagulation for venovenous extracorporeal membrane oxygenation (VV ECMO) patients. However, it is accompanied by frequent bleeding and thrombotic complications. The aim of the study was to demonstrate the feasibility of Enoxaparin anticoagulation for VV ECMO patients. This study is a retrospective analysis of VV ECMO patients on continuous intravenous Enoxaparin anticoagulation. The primary outcome was the incidence of bleeding, thrombotic, and neurological complications during ECMO support. The secondary outcome was an analysis of secondary and primary hemostasis profiles. Data from 38 patients were analyzed in this study. The incidence of bleeding complications was 5.3%, for thrombotic complications it was 2.6% and for neurological (bleeding/ischemic events) complications it was 10.5%. The targeted anti-Xa activity of 0.4-0.6 IU/mL was achieved and maintained during whole ECMO period in 28 patients (73.8%), not affecting the hemocoagulation profile represented by APTT-r 1.15 ± 0.2, TT 18.67 ± 3.35 s, PT/INR 1.21 ± 0.19, fibrinogen 5.39 ± 1.49 g/L, antithrombin, and platelet count. Primary hemostasis pathology was diagnosed in all patients by PFA 200 tests Col/EPI 279 ± 38 s and Col/ADP 249 ± 66 s. The running time of ECMO was 7.8 ± 3.4 days. Enoxaparin anticoagulation appears to be feasible for VV ECMO patients without an increase in adverse events. Further larger-sampled and comparative studies are needed in the future to support our findings.

S1714 Utilization and Outcomes of Extracorporeal Membrane Oxygenation in Patients With Cirrhosis

S1714 Utilization and Outcomes of Extracorporeal Membrane Oxygenation in Patients With Cirrhosis

Machine Learning Differentiates Extracorporeal Membrane Oxygenation Mortality Risk Profiles Among Trauma Patients.

Extracorporeal membrane oxygenation (ECMO) is resource intensive with high mortality. Identifying trauma patients most likely to derive a survival benefit remains elusive despite current ECMO guidelines. Our objective was to identify unique patient risk profiles using the largest database of trauma patients available. ECMO patients ≥16years were identified using Trauma Quality Improvement Program data (2010-2019). Machine learning K-median clustering (ML) utilized 101 variables including injury severity, demographics, comorbidities, and hospital stay information to generate unique patient risk profiles. Mortality and patient and center characteristics were evaluated across profiles. A total of 1037 patients were included with 33% overall mortality, mean age 32years, and median ISS = 26. The ML identified 3 unique patient risk profile groups. Although mortality rates were equivalent across the 3 groups, groups were distinguished by (Group 1) young (median 25years), severely injured (ISS = 34) patients with thoracic and head injuries (99%) via blunt mechanism (93%), and a high prevalence of ARDS (77%); (Group 2) relatively young (median 30years) and moderately injured (ISS = 22) patients with exposure-related injuries (11%); and (Group 3) older (median 46years) patients with a high proportion of comorbidities (69%) and extremity injuries (100%). There were no differences based on center ECMO volume, teaching status, or ACS-Level across all 3 groups. Machine learning compliments traditional analyses by identifying unique mortality risk profiles for trauma patients receiving ECMO. These details can further inform treatment guidelines, clinical decision making, and institutional criteria for ECMO usage.

Extracorporeal membrane oxygenation (ECMO) support for children with pulmonary hypertension: A single-institutional experience of outcomes.

Pediatric pulmonary arterial hypertension (PAH) can present with a wide spectrum of disease severity. Pulmonary hypertension (PH) crises can lead to acute decompensation requiring extracorporeal membrane oxygenation (ECMO) support, including extracorporeal cardiopulmonary resuscitation (eCPR). We evaluated outcomes for pediatric PH patients requiring ECMO. A single-institution retrospective review of pediatric PAH patients with World Symposium on PH (WSPH) groups 1 and 3 requiring ECMO cannulation from 2010 through 2022 (n = 20) was performed. Primary outcome was survival to hospital discharge. Secondary outcomes were survival to decannulation and 1-year survival. Of 20 ECMO patients, 16 (80%) survived to decannulation and 8 (40%) survived to discharge and 1 year follow up. Of three patients who had two ECMO runs; none survived. There were five patients who had eCPR for the first run; one survived to discharge. The univariate logistic regression model showed that venovenous ECMO was associated with better survival to hospital discharge than venoarterial ECMO, (OR: 0.12, 95% CI: 0.01-0.86, p = 0.046). PH medications (administered before, during, or after ECMO) were not associated with survival to discharge. For children with decompensated PAH requiring ECMO, mortality rate is high, and management is challenging. While VA ECMO is the main configuration for decompensated PH, VV ECMO could be considered if there is adequate ventricular function, presence of a systemic to pulmonary shunt, or an intercurrent treatable illness to improve survival to discharge. A multidisciplinary approach with requisite expertise should be utilized on a case-by-case basis until more reliable data is available to predict outcomes.

A comparison of some existing and novel methods for integrating historical models to improve estimation of coefficients in logistic regression

Abstract Model integration refers to the process of incorporating a fitted historical model into the estimation of a current study to increase statistical efficiency. Integration can be challenging when the current model includes new covariates, leading to potential model misspecification. We present and evaluate seven existing and novel model integration techniques, which employ both likelihood constraints and Bayesian informative priors. Using a simulation study of logistic regression, we quantify how efficiency—assessed by bias and variance—changes with the sample sizes of both historical and current studies and in response to violations to transportability assumptions. We also apply these methods to a case study in which the goal is to use novel predictors to update a risk prediction model for in-hospital mortality among pediatric extracorporeal membrane oxygenation patients. Our simulation study and case study suggest that (i) when historical sample size is small, accounting for this statistical uncertainty is more efficient; (ii) all methods lose efficiency when there exist differences between the historical and current data-generating mechanisms; (iii) additional shrinkage to zero can improve efficiency in higher-dimensional settings but at the cost of bias in estimation.

A comparative study of femoral artery and combined femoral and axillary artery cannulation in veno-arterial extracorporeal membrane oxygenation patients.

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a critical support technique for cardiac surgery patients. This study compares the outcomes of femoral artery cannulation vs. combined femoral and axillary artery cannulation in post-cardiotomy VA-ECMO patients. This study aimed to compare the clinical outcomes of critically ill patients post-cardiac surgery under VA-ECMO support using different cannulation strategies. Specifically, the focus was on the impact of femoral artery (FA) cannulation vs. combined femoral artery and axillary artery (FA+AA) cannulation on patient outcomes. Through a retrospective analysis, we compared 51 adult patients who underwent cardiac surgery and received VA-ECMO support based on the cannulation strategy employed-FA cannulation in 27 cases vs. FA+AA cannulation in 24 cases. The FA+AA group showed significant advantages over the FA group in terms of the incidence of chronic renal failure (CRF) (37.50% vs. 14.81%, p = 0.045), preoperative blood filtration requirement (37.50% vs. 11.11%, p = 0.016), decreased platelet count (82.67 ± 44.95 vs. 147.33 ± 108.79, p = 0.014), and elevated creatinine (Cr) levels (151.80 ± 60.73 vs. 110.26 ± 57.99, p = 0.041), although the two groups had similar 30-day mortality rates (FA group 40.74%, FA+AA group 33.33%). These findings underscore that a combined approach may offer more effective hemodynamic support and better clinical outcomes when selecting an ECMO cannulation strategy. Despite the FA+AA group patients presenting with more preoperative risk factors, this group has exhibited lower rates of complications and faster recovery during ECMO treatment. While there has been no significant difference in 30-day mortality rates between the two cannulation strategies, the FA+AA approach may be more effective in reducing complications and improving limb ischemia. These findings highlight the importance of individualized treatment strategies and meticulous monitoring in managing post-cardiac surgery ECMO patients.

Serum neurofilament light chain as a sensitive biomarker for neuromonitoring during extracorporeal membrane oxygenation

The use of extracorporeal membrane oxygenation (ECMO) has grown rapidly, driven by the COVID-19 pandemic. Despite its widespread adoption, neurological complications pose a significant risk, impacting both mortality and survivors’ quality of life. Detecting these complications is challenging due to sedation and the heterogeneous nature of ECMO-associated neurological injury. Still, consensus of neurologic monitoring during ECMO is lacking since utilization and effectiveness of current neuromonitoring methods are limited. Especially in view of the heterogeneous nature of neurological injury during ECMO support an easily acquirable biomarker tracing neuronal damage independently from the underlying pathomechanism would be favorable. In a single-center prospective study on 34 severe acute respiratory distress syndrome (ARDS) patients undergoing ECMO, we explored the potential of serum neurofilament light chain levels (NfL) as a biomarker for neurological complications and its predictive power towards the overall outcome of ECMO patients. Individuals experiencing neurological complications (41%) demonstrated a notable rise in NfL levels (Tbaseline median 92.95 pg/ml; T24h median 132 pg/ml (IQR 88.6–924 pg/ml), p = 0.008; T7d median 248 pg/ml (IQR 157–1090 pg/ml), p = 0.001). Moreover, under ECMO therapy, these patients exhibited markedly elevated concentrations compared to those without neurological complications (T24h median 70.75 pg/ml (IQR 22.2–290 pg/ml), p = 0.023; T7d median 128 pg/ml (IQR 51.8–244 pg/ml), p = 0.002). There was no significant difference in the NfL dynamics between surviving patients and those who died during or shortly after ECMO therapy. While NfL indicates neuro-axonal damage during intensive care with ECMO therapy, we could not identify any correlation between survival outcome and the levels of NfL, indicating that NfL may not serve as a prognostic marker for survival. Nevertheless, additional studies involving a larger patient cohort are required.