VA ECMO Research Articles

Lactate-Based Difference as a Determinant of Outcomes following Surgery for Type A Acute Aortic Dissection: A Multi-Centre Study.

All patients referred to the three cardiovascular centres between January 2005 and December 2022 were included in the study. The inclusion criteria required the presence of a lesion involving the ascending aorta, symptoms within 7 days of surgery, and referral for primary surgical repair of TAAAD based on recommendations, with consideration for other concomitant major cardiac surgical procedures needed during TAAAD and retrograde extension of TAAAD. We conducted an analysis of both continuous and categorical variables and utilised predictive mean matching to fill in missing numeric features. For missing binary variables, we used logistic regression to impute values. We specifically targeted early postoperative mortality and employed LASSO regression to minimise potential collinearity of over-fitting variables and variables measured from the same patient. A total of 633 patients were recruited for the study, out of which 449 patients had complete preoperative arterial lactate data. The average age of the patients was 64 years, and 304 patients were male (67.6%). The crude early postoperative mortality rate was 24.5% (110 out of 449 patients). The mortality rate did not show any significant difference when comparing conservative and extensive surgeries. However, malperfusion had a significant impact on mortality [48/131 (36.6%) vs. 62/318 (19.5%), p < 0.001]. Preoperative arterial lactates were significantly elevated in patients with malperfusion. The optimal prognostic threshold of arterial lactate for predicting early postoperative mortality in our cohort was ≥2.6 mmol/L. The arterial lactate concentration in patients referred for TAAAD is an independent factor for both operative mortality and postoperative complications. In addition to mortality, patients with an upper arterial lactate cut-off of ≥2.6 mmol/L face significant risks of VA ECMO and the need for dialysis within the first 48 h after surgery. To improve recognition and facilitate rapid transfer and surgical treatment protocol, more diligent efforts are required in the management of malperfusion in TAAAD.

Platelet Reactivity on ECMO: Role of VerifyNow

Viscoelastic assays help in identifying disorders of clotting factors, platelet function, and detection of excessive fibrinolysis. Rotational thromboelastometry (ROTEM) assesses quantitative and qualitative aspects of whole blood coagulation which allows for the determination of the mechanism of hemostatic disturbance. This helps clinicians in targeting the correct blood component therapy transfusion. Now, using verify we aim to study platelet reactivity, VA ECMO which will reflect the platelet aggregation response to an aggregating agent like Aspirin and thus know the etiology of bleeding on VA ECMO, to know the right component therapy to be transfused with a Point of Care test. For extracorporeal membrane oxygenation, although the conventional laboratory tests are used to monitor anticoagulation on whole blood, viscoelastic tests reflect coagulation status like no other standard laboratory tests. They show the status of color propagation, formation, and stabilization. It was reported that platelet function was impaired over time in all parameters with different activators.

Viscoelastic Testing on Venoarterial Extracorporeal Membrane Oxygenation: Need or Greed?

Extracorporeal life support (ECLS) is a life support modality that is being used in life-threatening cardiac and/or respiratory failure; in neonates, children, and adults. The risk of bleeding and other coagulation-related issues is unavoidable. Hence, while conducting ECLS, a patient-tailored approach is better than the generalized approach for bleeding management. There are no established guidelines for heparin use and its monitoring during ECLS in a bleeding patient on VA ECMO. Likewise, heparin and its adjuncts, though mentioned in the literature, have no consensus on what exact steps to follow in an adverse condition. Having a protocol for anticoagulation and its monitoring is of paramount importance in any center practicing ECLS. This review aims to seek the incidence of bleeding and thrombosis while on ECMO with the use of routine anticoagulant heparin and justify the need for the use of viscoelastic tests on VA ECMO.

Growing Evidence for LV Unloading in VA ECMO.

Impressively increasing availability of mechanical circulatory/cardiac support systems (MCSs) worldwide, together with the deepening of the knowledge of critical care medical practitioners, has inevitably led to the discussion about further improvements of intensive care associated to MCS. An appealing topic of the left ventricle (LV) overload related to VA ECMO support endangering myocardial recovery is being widely discussed within the scientific community. Unloading of LV leads to the reduction in LV end-diastolic pressure, reduction in pressure in the left atrium, and decrease in the LV thrombus formation risk. Consequently, better conditions for myocardial recovery, with comfortable filling pressures and a better oxygen delivery/demand ratio, are achieved. The combination of VA ECMO and Impella device, also called ECPELLA, seems to be a promising strategy that may bring the improvement of CS mortality rates. The series of presented trials and meta-analyses clearly showed the potential benefits of this strategy. However, the ongoing research has brought a series of new questions, such as whether Impella itself is the only appropriate unloading modality, or any other approach to unload LV would be beneficial in the same way. Benefits and potential risks of LV unloading and its timing are being discussed in this current review.

Extracorporeal cardiopulmonary resuscitation-When the heart no longer functions

Extracorporeal cardiopulmonary resuscitation (ECPR) is an option for restoring blood circulation in patients with refractory circulatory failure. While conventional resuscitation measures are being continued, venoarterial extracorporeal membrane oxygenation (VA ECMO) is established in patients with cardiac arrest. This bypass can compensate for the functions of the heart and lungs until recovery of organ function. The benefit of ECPR compared to conventional resuscitation appears to be evident, especially after aprolonged resuscitation period; however, in three prospective randomized controlled studies an advantage has not yet been conclusively proven for widespread use in clinical routine. ECPR systems are complex and resource-intensive and should therefore be limited to specialized centers where sufficient numbers of patients are treated to ensure ahigh level of expertise in the teams.

The addition of Cytosorb in patients on VA-ECMO improves urinary output and ICU survival.

The aim of this study was to analyze the efficiency of CytoSorb adsorber in patients presenting with cardiogenic shock and treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO). Sixteen patients put on VA ECMO due to cardiogenic shock were included, stratified according to the use of Cytosorb adsorber in the first 24 h and compared across different clinical outcomes. Significantly lower vasopressor doses were required among patients treated with Cytosorb at the initiation and before weaning from ECMO. Furthermore, these patients showed significantly higher urine output before weaning and lower lactate levels during the extracorporeal support. Finally, the mortality rate was lower among the Cytosorb therapy group (22.2% vs 57.1%). While a decrease in vasopressor doses was already associated with CytoSorb use, this is the first study showing an increase in urinary output and a trend towards better survival among patients on VA ECMO treated with CytoSorb.

Transfusion of red blood cells in venoarterial extracorporeal membrane oxygenation: A multicenter retrospective observational cohort study.

Evidence-based recommendations for transfusion in patients with venoarterial extracorporeal membrane oxygenation (VA ECMO) are scarce. The current literature is limited to single-center studies with small sample sizes, therefore complicating generalizability. This study aims to create an overview of red blood cell (RBC) transfusion in VA ECMO patients. This international mixed-method study combined a survey with a retrospective observational study in 16 centers. The survey inventoried local transfusion guidelines. Additionally, retrospective data of all adult patients with a VA ECMO run >24 h (January 2018 until July 2019) was collected of patient, ECMO, outcome, and daily transfusion parameters. All patients that received VA ECMO for primary cardiac support were included, including surgical (i.e., post-cardiotomy) and non-surgical (i.e., myocardial infarction) indications. The primary outcome was the number of RBC transfusions per day and in total. Univariable logistic regressions and a generalized linear mixed model (GLMM) were performed to assess factors associated with RBC transfusion. Out of 419 patients, 374 (89%) received one or more RBC transfusions. During a median ECMO run of 5 days (1st-3rd quartile 3-8), patients received a median total of eight RBC units (1st-3rd quartile 3-17). A lower hemoglobin (Hb) prior to ECMO, longer ECMO-run duration, and hemorrhage were associated with RBC transfusion. After correcting for duration and hemorrhage using a GLMM, a different transfusion trend was found among the regimens. No unadjusted differences were found in overall survival between either transfusion status or the different regimens, which remained after adjustment for potential confounders. RBC transfusion in patients on VA ECMO is very common. The sum of RBC transfusions increases rapidly after ECMO initiation, and is dependent on the Hb threshold applied. This study supports the rationale for prospective studies focusing on indications and thresholds for RBC transfusion.

117: Predictors of weaning failure in VA ECMO after cardiac surgery

117: Predictors of weaning failure in VA ECMO after cardiac surgery

6: A Novel Approach to Measuring Physiologic Changes during Ambulation for a Patient with Post Infarct VSD Supported on Femoral IABP and VA ECMO

6: A Novel Approach to Measuring Physiologic Changes during Ambulation for a Patient with Post Infarct VSD Supported on Femoral IABP and VA ECMO

56: Comparison of Outcomes of Central and Peripheral VA ECMO Cannulation for Pediatric Patients with Septic Shock

56: Comparison of Outcomes of Central and Peripheral VA ECMO Cannulation for Pediatric Patients with Septic Shock

73: A safe and effective method for percutaneous, awake, bedside decannulation of peripheral VA ECMO using vascular closure devices: a case series.

73: A safe and effective method for percutaneous, awake, bedside decannulation of peripheral VA ECMO using vascular closure devices: a case series.

208: Impact of a Multidisciplinary C-Shock Team on the Survival of Patients Undergoing VA ECMO in an Academic Quaternary Hospital Center.

208: Impact of a Multidisciplinary C-Shock Team on the Survival of Patients Undergoing VA ECMO in an Academic Quaternary Hospital Center.

Left ventricular decompression in veno-arterial extracorporeal membrane oxygenation

Objective: Our study investigates the frequency and determines the characteristics and outcomes of patients with venoarterial extracorporeal membrane oxygenation (VA-ECMO) support requiring left ventricular unloading at Ha Noi Heart hospital.&#x0D; Methods: A cross-sectional descriptive study was conducted among 84 patients undergoing VA- ECMO between December 2018 and December 2021 at Ha Noi Heart hospital. Signs of left ventricular distension in VA-ECMO (Inadequate arterial blood pressure pulsatility, “smoke like” effect in left ventricular, reduced aortic valve opening/absent aortic valve closure, pulmonary edema, left ventricular distension) were studied before and at 24 hours, 48 hours and 72 hours after VA-ECMO support.&#x0D; Results: Left ventricular distention requiring decompression occurs in 44,1% of patients supported with VA-ECMO 3.6% (left ventricular distension), inadequate arterial blood pressure pulsatility (77,4%), “smoke like” effect in left ventricular (53,6%), pulmonary edema 47 ,6%; reduced aortic valve opening/absent aortic valve closure in 35,7% of the cases. Left ventricular decompression may improve clinical outcomes from 48 hours onwards (p&lt;0.05). There were no differences in age, left ventricular ejection fraction before VA-ECMO, ECRP rates, continuous renal replacement therapy rates, duration of mechanical ventilation, duration of ECMO, hospital length of stay and diagnosis of patients with and without left ventricular unloading (p&gt;0.05). The proportion of patients using invasive left ventricular decompression who successful weaning from VA- ECMO was significantly higher than in the group without left ventricular unloading (94,5% versus 74,4%; p&lt;0.05).The survival rate of patients using left ventricular unloading tended to be higher than that in the group without left ventricular decompression (72,9% vs 53,2%; p&gt;0.05) ). Complications of invasive left ventricular decompression included 1 patient with occlusion of the junction requires removal of the left atrial drainage.&#x0D; Conclusion: Left heart decompression may contribute to increasing the success rate of VA-ECMO weaning and may help to improve the survival rate of patients with VA ECMO.

The interaction of thrombocytopenia, hemorrhage, and platelet transfusion in venoarterial extracorporeal membrane oxygenation: a multicenter observational study

BackgroundThrombocytopenia, hemorrhage and platelet transfusion are common in patients supported with venoarterial extracorporeal membrane oxygenation (VA ECMO). However, current literature is limited to small single-center experiences with high degrees of heterogeneity. Therefore, we aimed to ascertain in a multicenter study the course and occurrence rate of thrombocytopenia, and to assess the association between thrombocytopenia, hemorrhage and platelet transfusion during VA ECMO.MethodsThis was a sub-study of a multicenter (N = 16) study on transfusion practices in patients on VA ECMO, in which a retrospective cohort (Jan-2018–Jul-2019) focusing on platelets was selected. The primary outcome was thrombocytopenia during VA ECMO, defined as mild (100–150·109/L), moderate (50–100·109/L) and severe (< 50·109/L). Secondary outcomes included the occurrence rate of platelet transfusion, and the association between thrombocytopenia, hemorrhage and platelet transfusion, assessed through mixed-effect models.ResultsOf the 419 patients included, median platelet count at admission was 179·109/L. During VA ECMO, almost all (N = 398, 95%) patients developed a thrombocytopenia, of which a significant part severe (N = 179, 45%). One or more platelet transfusions were administered in 226 patients (54%), whereas 207 patients (49%) suffered a hemorrhagic event during VA ECMO. In non-bleeding patients, still one in three patients received a platelet transfusion. The strongest association to receive a platelet transfusion was found in the presence of severe thrombocytopenia (adjusted OR 31.8, 95% CI 17.9–56.5). After including an interaction term of hemorrhage and thrombocytopenia, this even increased up to an OR of 110 (95% CI 34–360).ConclusionsThrombocytopenia has a higher occurrence than is currently recognized. Severe thrombocytopenia is strongly associated with platelet transfusion. Future studies should focus on the etiology of severe thrombocytopenia during ECMO, as well as identifying indications and platelet thresholds for transfusion in the absence of bleeding.Trial registration: This study was registered at the Netherlands Trial Registry at February 26th, 2020 with number NL8413 and can currently be found at https://trialsearch.who.int/Trial2.aspx?TrialID=NL8413.

Prognostic impact of lung computed tomography density in cardiogenic shock patients with veno-arterial extracorporeal membrane oxygenation.

Pulmonary complications often occur in patients receiving veno-arterial extracorporeal membrane oxygenation (VA ECMO). However, the prognostic impact of lung damage has not been fully elucidated. This single-center retrospective observational study targeted patients with cardiogenic shock who received VA ECMO between 2012 and 2021. This study included 65 patients who underwent chest computed tomography (CT) on VA ECMO, followed by escalation to central mechanical circulatory support (MCS) with left ventricular venting. The average density of lung CT images was measured using region-of-interest methods, and the primary endpoint was 180-day all-cause death after escalation to the central MCS. Twenty-two patients (34%) developed 180-day all-cause death. According to the Cox regression analysis, age (hazard ratio [HR], 1.08; 95% confidence interval [CI], 1.03-1.14; p = 0.001), ischemic etiology (HR, 5.53; 95% CI, 2.09-14.62; p < 0.001), duration of VA ECMO support (HR, 1.19; 95% CI, 1.00-1.40; p = 0.045), and lung CT density (≥ -481 Hounsfield unit [HU]) (HR, 6.33; 95% CI, 2.26-17.72; p < 0.001) were independently associated with all-cause death. Receiver operating characteristic curve analysis determined that lung CT density ≥ -481 HU is an optimal cutoff value for predicting all-cause death (area under the curve [AUC], 0.72). The 180-day overall survival rate for patients with high lung CT density (≥ -481 HU) was significantly lower than that for those with low lung CT density (< -481 HU) (44.4% vs. 81.6%, respectively, p = 0.002). Higher lung CT density could be a useful predictor of death in patients with VA ECMO requiring central MCS escalation.

Blend to Limit OxygEN in ECMO: A RanDomised ControllEd Registry (BLENDER) Trial: Study Protocol and Statistical Analysis Plan

IntroductionCritically ill patients supported with venoarterial extracorporeal membrane oxygenation (VA ECMO) are at risk of developing severe arterial hyperoxia, which has been associated with increased mortality. Lower saturation targets in this population may lead to deleterious episodes of severe hypoxia. This manuscript describes the protocol and statistical analysis plan for the Blend to Limit OxygEN in ECMO: A RanDomised ControllEd Registry (BLENDER) Trial. DesignThe BLENDER trial is a pragmatic, multicentre, registry-embedded, randomised clinical trial., registered at ClinicalTrials.gov (NCT03841084) and approved by The Alfred Hospital Ethics Committee project ID HREC/50486/Alfred-2019. Participants and settingPatients supported by VA ECMO for cardiogenic shock or cardiac arrest who are enrolled in the Australian national ECMO registry. InterventionThe study compares a conservative oxygenation strategy (target arterial saturations 92–96%) with a liberal oxygenation strategy (target 97–100%). Main Outcome MeasuresThe primary outcome is the number of intensive care unit (ICU)-free days for patients alive at day 60. Secondary outcomes include duration of mechanical ventilation, ICU and hospital mortality, the number of hypoxic episodes, neurocognitive outcomes, and health economic analyses. The 300-patient sample size enables us to detect a 3-day difference in ICU-free days at day 60, assuming a mean ICU-free days of 11 days, with a risk of type 1 error of 5% and power of 80%. Data will be analysed according to a predefined analysis plan. Findings will be disseminated in peer-reviewed publications. ConclusionsThis paper details the protocol and statistical analysis plan for the BLENDER trial, a registry-embedded, multicentre interventional trial comparing liberal and conservative oxygenation strategies in VA ECMO.

Smaller Return Cannula in Venoarterial Extracorporeal Membrane Oxygenation Does Not Increase Hemolysis: A Single-Center, Cohort Study.

The aim of this study was to explore the association between arterial return cannula diameter and hemolysis during peripheral VA ECMO. We identified 158 adult patients who received peripheral VA ECMO at our institution from the national ECMO database (EXCEL) between January 2019 and July 2021. We classified patients into a small cannula group (15 Fr diameter, n = 45) and a large cannula group (≥17 Fr diameter, n = 113), comparing incidences of clinical hemolysis and plasma free hemoglobin (pfHb). Moderate hemolysis is defined as having pfHb 0.05-0.10 g/L and severe hemolysis as having pfHb >0.10 g/L sustained for at least two consecutive readings or leading to a circuit change. There were no significant differences in rates of moderate hemolysis between small and large cannula groups (1 vs. 6; p = 0.39) and severe hemolysis (0 vs. 3; p = 0.27), nor was the pfHb level significantly different at 4 hours (0.086 ± 0.096 vs. 0.112 ± 0.145 g/L; p = 0.58) and at 24 hours (0.042 ± 0.033 vs. 0.051 ± 0.069 g/L; p = 0.99). There were no increased rates of hemolysis when comparing small versus large arterial return cannula diameter in peripheral VA ECMO.

Lower Limb Ischemia in Surgical Femoral Veno-Arterial Extracorporeal Membrane Oxygenation

To analyze the incidence, clinical impact on survival, and risk factors of lower limb ischemia (LLI) of surgical peripheral femoral venoarterial extracorporeal membrane oxygenation (VA ECMO) in the current era. A retrospective analysis of the authors' institutional database of VA ECMO was performed. Patients were divided into 2 groups according to the occurrence of LLI. The primary endpoint was survival to hospital discharge. Risk factors of LLI were searched with multivariate analyses. University hospital. Adult patients receiving peripheral VA ECMO for refractory cardiogenic shock and cardiac arrest. None. From January 2018 to December 2021, 188 patients (mean age: 52.0 ± 14.1 years; 63.8% male, 36.2% female) received peripheral VA ECMO. Male sex was more prevalent in the group without LLI (65.9% v 33.3%; p=0.031). Twelve (6.4%) patients developed LLI during VA ECMO support (n=6) or after VA ECMO removal (n=6). Survival to hospital discharge was not statistically different between patients with and without LLI (50.0% v 48.3%; p=0.571). Female sex patients were at increased risk for LLI (odds ratio 4.38, 95% CI 1.21-15.81; p=0.024). Peripheral femoral VA ECMO through a surgical approach is associated with a low LLI rate, which does not increase the risk of in-hospital mortality. The female sex is an independent risk factor for LLI.

On-Support and Postweaning Mortality in Postcardiotomy Extracorporeal Membrane Oxygenation

BackgroundPostcardiotomy venoarterial extracorporeal membrane oxygenation (VA ECMO) is characterized by discrepancies between weaning and survival-to-discharge rates. This study analyzes the differences between postcardiotomy VA ECMO patients who survived, died on ECMO, or died after ECMO weaning. Causes of death and variables associated with mortality at different time points are investigated. MethodsThe retrospective, multicenter, observational Postcardiotomy Extracorporeal Life Support Study (PELS) includes adults requiring postcardiotomy VA ECMO between 2000 and 2020. Variables associated with on-ECMO mortality and postweaning mortality were modeled using mixed Cox proportional hazards, including random effects for center and year. ResultsIn 2058 patients (men, 59%; median age, 65 years; interquartile range [IQR], 55-72 years), weaning rate was 62.7%, and survival to discharge was 39.6%. Patients who died (n = 1244) included 754 on-ECMO deaths (36.6%; median support time, 79 hours; IQR, 24-192 hours), and 476 postweaning deaths (23.1%; median support time, 146 hours; IQR, 96-235.5 hours). Multiorgan (n = 431 of 1158 [37.2%]) and persistent heart failure (n = 423 of 1158 [36.5%]) were the main causes of death, followed by bleeding (n = 56 of 754 [7.4%]) for on-ECMO mortality and sepsis (n = 61 of 401 [15.4%]) for postweaning mortality. On-ECMO death was associated with emergency surgery, preoperative cardiac arrest, cardiogenic shock, right ventricular failure, cardiopulmonary bypass time, and ECMO implantation timing. Diabetes, postoperative bleeding, cardiac arrest, bowel ischemia, acute kidney injury, and septic shock were associated with postweaning mortality. ConclusionsA discrepancy exists between weaning and discharge rate in postcardiotomy ECMO. Deaths occurred during ECMO support in 36.6% of patients, mostly associated with unstable preoperative hemodynamics. Another 23.1% of patients died after weaning in association with severe complications. This underscores the importance of postweaning care for postcardiotomy VA ECMO patients.

Modeling the effect of patient size on cerebral perfusion during veno-arterial extracorporeal membrane oxygenation.

A well-known complication of veno-arterial extracorporeal membrane oxygenation (VA ECMO) is differential hypoxia, in which poorly-oxygenated blood ejected from the left ventricle mixes with and displaces well-oxygenated blood from the circuit, thereby causing cerebral hypoxia and ischemia. We sought to characterize the impact of patient size and anatomy on cerebral perfusion under a range of different VA ECMO flow conditions. We use one-dimensional (1D) flow simulations to investigate mixing zone location and cerebral perfusion across 10 different levels of VA ECMO support in eight semi-idealized patient geometries, for a total of 80 scenarios. Measured outcomes included mixing zone location and cerebral blood flow (CBF). Depending on patient anatomy, we found that a VA ECMO support ranging between 67-97% of a patient's ideal cardiac output was needed to perfuse the brain. In some cases, VA ECMO flows exceeding 90% of the patient's ideal cardiac output are needed for adequate cerebral perfusion. Individual patient anatomy markedly affects mixing zone location and cerebral perfusion in VA ECMO. Future fluid simulations of VA ECMO physiology should incorporate varied patient sizes and geometries in order to best provide insights toward reducing neurologic injury and improved outcomes in this patient population.