Extracorporeal Membrane Oxygenation (VA-ECMO) in Management of Cardiogenic Shock

Current role of extracorporeal membrane oxygenation for the management of trauma patients: Indications and results

Extracorporeal membrane oxygenation (ECMO) has emerged as a vital circulatory life support measure for patients with critical cardiac or pulmonary conditions unresponsive to conventional therapies. ECMO allows blood to be extracted from a patient and introduced to a machine that oxygenates blood and removes carbon dioxide. This blood is then reintroduced into the patient’s circulatory system. This process makes ECMO essential for treating various medical conditions, both as a standalone therapy and as adjuvant therapy. Veno-venous (VV) ECMO primarily supports respiratory function and indicates respiratory distress. Simultaneously, veno-arterial (VA) ECMO provides hemodynamic and respiratory support and is suitable for cardiac-related complications. This study reviews recent literature to elucidate the evolving role of ECMO in trauma care, considering its procedural intricacies, indications, contraindications, and associated complications. Notably, the use of ECMO in trauma patients, particularly for acute respiratory distress syndrome and cardiogenic shock, has demonstrated promising outcomes despite challenges such as anticoagulation management and complications such as acute kidney injury, bleeding, thrombosis, and hemolysis. Some studies have shown that VV ECMO was associated with significantly higher survival rates than conventional mechanical ventilation, whereas other studies have reported that VA ECMO was associated with lower survival rates than VV ECMO. ECMO plays a critical role in managing trauma patients, particularly those with acute respiratory failure. Further research is necessary to explore the full potential of ECMO in trauma care. Clinicians should have a clear understanding of the indications and contraindications for the use of ECMO to maximize its benefits in treating trauma patients.

Improving the Prioritization of Heart Transplantation Candidates for Optimal Clinical Outcomes: A Narrative Review

PURPOSE OF REVIEW

This narrative review evaluates the limitations of current heart transplantation allocation models, which prioritize medical urgency and waitlist time but fail to adequately predict long-term post-transplant outcomes. It aims to identify advanced metrics that can strengthen the prioritization framework while addressing persistent racial, geographic, and socioeconomic inequities in access to transplantation.

RECENT FINDINGS

Recent research indicates that incorporating frailty, nutritional status, immunological compatibility, and pulmonary hemodynamics into allocation frameworks can enhance the prediction of transplant outcomes. The growing use of mechanical circulatory support (MCS) as a bridge to transplantation provides stabilization for critically ill patients; however, disparities in access persist. Studies continue to emphasize the barriers faced by minority and pediatric populations, highlighting the need for expanded donor networks and improved matching criteria. This review highlights the necessity of shifting transplantation prioritization toward multidimensional candidate evaluations that consider both clinical complexity and long-term outcomes. Policy reforms aimed at addressing healthcare disparities and optimizing donor utilization are crucial for improving patient outcomes. Future research should focus on assessing the effectiveness of advanced allocation models, such as continuous distribution frameworks, to promote equitable and sustainable transplantation systems.

Pitfalls of computed tomography angiography examination in veno-arterial extracorporeal membrane oxygenation patients: a case report of a patient with cardiac rupture

BACKGROUND

Veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) is commonly used for patients with cardiac arrest, cardiogenic shock, or heart failure and is a life-saving technique. Computed tomography angiography (CTA) examination in patients on ECMO presents certain challenges. Due to the dual circulation characteristics of blood flow in ECMO patients, vascular imaging and interpretation can be difficult and may even present pitfalls.

CASE PRESENTATION

A 59-year-old male was admitted with a diagnosis of cardiogenic shock due to "sudden onset of chest discomfort for 6 hours and altered mental status for 4 hours". He underwent V-A ECMO treatment twice and had two aortic CTA examinations. The initial CTA mistakenly diagnosed an aortic dissection. Considering the dual circulation blood flow characteristic in ECMO patients, a second CTA was performed. Combined with echocardiography, the patient was accurately diagnosed with left ventricular rupture and underwent left ventricular rupture repair surgery. The patient was successfully weaned off ECMO, transferred out of the ICU, and eventually discharged in good condition.

CONCLUSION

The unique hemodynamics of V-A ECMO patients necessitate interpreting CTA examinations with an understanding of the dual circulation characteristic to avoid misdiagnosis.

A Systematic Review and Meta-Analysis of the Efficacy and Safety of Combined Mechanical Circulatory Support in Acute Myocardial Infraction Related Cardiogenic Shock

BACKGROUND

Acute myocardial infarction-related cardiogenic shock (AMICS) is a severe complication associated with exceedingly high mortality rates. While mechanical circulatory support (MCS) has emerged as a potential intervention, the evidence base for independent MCS use remains weak. In contrast, systematic reviews of observational studies have revealed significant mortality reduction when a combination of MCS was used: VA-ECMO in conjunction with a left ventricular (LV) unloading device (Impella or IABP). The ongoing dilemma concerning the selection between two LV unloading devices (VA-ECMO + Impella vs. VA-ECMO + IABP) warrants further investigation and clarification.

AIM

This is the first systematic review and meta-analysis assessing the short-term efficacy and safety of VA-ECMO + Impella versus VA-ECMO + IABP in treatment of AMICS.

METHODS

A systematic search was performed on the EMBASE, MEDLINE, and Cochrane databases. Studies reporting the short-term (30-day/inpatient) mortality and complications of adult patients with AMICS treated with VA-ECMO + Impella and VA-ECMO + IABP were included. Subgroup analysis was performed including studies with ACS predominant CS (CS etiology 100% by AMI).

RESULTS

Four observational studies with 14,247 patients were included. There was no significant difference in mortality between VA-ECMO + Impella and VA-ECMO + IABP (56.5% vs. 66.5%; OR, 0.90; 95% CI, 0.79-1.02; p = 0.09). However, VA-ECMO + Impella was associated with significantly lower mortality in patients with ACS predominant CS (53.2% vs. 67.7%; OR, 0.72; 95% CI, 0.62-0.85; p < 0.0001). VA-ECMO + Impella was concomitantly associated with a significantly higher risk of complications.

CONCLUSIONS

When comparing LV unloading devices in patients with AMICS requiring a combination of MCS, VA-ECMO + Impella was superior in mortality reduction only in the cohort where 100% of CS was caused by AMI.

Prevalence and risk factors for in-hospital mortality of adult patients on veno-arterial extracorporeal membrane oxygenation for cardiogenic shock and cardiac arrest: A systematic review and meta-analysis

OBJECTIVES

To synthesize quantitative research findings on the prevalence and risk factors for in-hospital mortality of patients on veno-arterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

A comprehensive search was conducted for the period from May 2008 to December 2023 by searching the five electronic databases of PubMed, CINAHL, Web of Science, EMBASE, and Cochrane library. The quality of included studies was assessed using the Newcastle-Ottawa scale. The meta-analysis estimated the pooled odds ratio or standard mean difference and 95% confidence intervals.

RESULTS

A total of twenty-five studies with 10,409 patients were included in the analysis. The overall in-hospital mortality of patients on VA-ECMO was 56.7 %. In the subgroup analysis, in-hospital mortality of VA-ECMO for cardiogenic shock and cardiac arrest was 49.2 % and 75.2 %, respectively. The number of significant factors associated with an increased risk of in-hospital mortality in the pre-ECMO period (age, body weight, creatinine, chronic kidney disease, pH, and lactic acid) was greater than that in the intra- and post-ECMO periods. Renal replacement, bleeding, and lower limb ischemia were the most significant risk factors for in-hospital mortality in patients receiving VA-ECMO.

CONCLUSION

Early detection of the identified risk factors can contribute to reducing in-hospital mortality in patients on VA-ECMO. Intensive care unit nurses should provide timely and appropriate care before, during, and after VA-ECMO.

IMPLICATIONS FOR CLINICAL PRACTICE

Intensive care unit nurses should be knowledgeable about factors associated with the in-hospital mortality of patients on VA-ECMO to improve outcomes. The present findings may contribute to developing guidelines for reducing in-hospital mortality among patients considering ECMO.

Impact of Left Ventricular Venting on Acute Brain Injury in Patients with Cardiogenic Shock: An Extracorporeal Life Support Organization Registry Analysis

Background

While left ventricular (LV) venting reduces LV distension in cardiogenic shock patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO), it may also amplify risk of acute brain injury (ABI). We investigated the hypothesis that LV venting is associated with increased risk of ABI. We also compared ABI risk of the two most common LV venting strategies, percutaneous microaxial flow pump (mAFP) and intra-aortic balloon pump (IABP).

Methods

The Extracorporeal Life Support Organization registry was queried for patients on peripheral VA-ECMO for cardiogenic shock (2013-2024). ABI was defined as hypoxic-ischemic brain injury, ischemic stroke, or intracranial hemorrhage. Secondary outcome was hospital mortality. We compared no LV venting with 1) LV venting, 2) mAFP, and 3) IABP using multivariable logistic regression. To compare ABI risk of mAFP vs. IABP, propensity score matching was performed.

Results

Of 13,276 patients (median age=58.2, 69.9% male), 1,456 (11.0%) received LV venting (65.5% mAFP and 29.9% IABP), and 525 (4.0%) had ABI. After multivariable regression, LV-vented patients had increased odds of ABI (adjusted odds ratio (aOR)=1.76, 95% CI=1.29, 2.37, p<0.001) but no difference in mortality (aOR=1.08, 95% CI=0.91-1.28, p=0.39) compared to non-LV-vented patients. In the propensity- matched cohort of IABP (n=231) vs. mAFP (n=231) patients, there was no significant difference in odds of ABI (aOR=1.35, 95%CI=0.69-2.71, p=0.39) or mortality (aOR=0.88, 95%CI=0.58-1.31, p=0.52).

Conclusions

LV venting was associated with increased odds of ABI but not mortality in patients receiving peripheral VA-ECMO for cardiogenic shock. There was no difference in odds of ABI or mortality for IABP vs. mAFP patients.

Clinical Perspective

In patients receiving peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock, left ventricular venting is associated with increased odds of acute brain injury (ABI) but not mortality. However, mode of venting-intra-aortic balloon pump (IABP) or percutaneous microaxial flow pump (mAFP)-does not appear to impact either odds of ABI or mortality. These findings highlight a link between venting strategies and neurological outcomes in this high-risk population. Clinicians must weigh the benefits of venting against ABI risk when managing neurocritically ill patients, though our findings provide reassurance clinicians that both IABP and mAFP may offer comparable neurologic safety profiles.

Central versus peripheral VA ECMO for cardiogenic shock: an 8-year experience of a tertiary cardiac surgery center in Greece

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA ECMO) has emerged as an effective rescue therapy in patients with cardiogenic shock refractory to standard treatment protocols, and its use has been rising worldwide in the last decade. Although experience and availability are growing, outcomes remain poor. There is need for evidence to improve clinical practice and outcomes.

METHODS

We retrospectively reviewed the medical records of all patients who were supported with VA ECMO for cardiogenic shock at our institution between January 2015 and January 2023. The study purpose was to compare outcomes between patients who were supported with central versus peripheral configuration.

RESULTS

ECMO was applied in 108 patients, 48 (44%) of whom received central configuration and 60 (56%) peripheral. Patients supported with central VA ECMO were more likely to be supported for post-cardiotomy shock (odds ratio [OR] 4.6 [95% confidence interval (CI) 2.03-10.41]), while patients in the peripheral group were predominantly treated for chronic heart failure decompensation (OR 9.4 [95% CI 1.16-76.3]). Central VA ECMO had lower survival rates during ECMO support (29.2% versus 51.7%, p = 0.018) and at discharge (8% versus 37%, p = 0.001). These patients were at high risk of complications, such as acute kidney injury (AKI) (OR 2.37 [95% CI 1.06-5.3], p = 0.034) and major bleeding (OR 3.08 [95% CI 1.36-6.94], p < 0.001).

CONCLUSIONS

Patients on central VA ECMO were supported mainly for post-cardiotomy shock, presented with more complications such as major bleeding and AKI, and had worse survival to hospital discharge compared with patients on peripheral VA ECMO. Patient selection, timing of implementation, cannulation strategy, and configuration remain the main determinants of clinical outcome.

Acute lung injury and post-cardiac arrest syndrome: a narrative review

BACKGROUND

Post-cardiac arrest syndrome (PCAS) presents a multifaceted challenge in clinical practice, characterized by severe neurological injury and high mortality rates despite advancements in management strategies. One of the important critical aspects of PCAS is post-arrest lung injury (PALI), which significantly contributes to poor outcomes. PALI arises from a complex interplay of pathophysiological mechanisms, including trauma from chest compressions, pulmonary ischemia-reperfusion (IR) injury, aspiration, and systemic inflammation. Despite its clinical significance, the pathophysiology of PALI remains incompletely understood, necessitating further investigation to optimize therapeutic approaches.

METHODS

This review comprehensively examines the existing literature to elucidate the epidemiology, pathophysiology, and therapeutic strategies for PALI. A comprehensive literature search was conducted to identify preclinical and clinical studies investigating PALI. Data from these studies were synthesized to provide a comprehensive overview of PALI and its management.

RESULTS

Epidemiological studies have highlighted the substantial prevalence of PALI in post-cardiac arrest patients, with up to 50% of survivors experiencing acute lung injury. Diagnostic imaging modalities, including chest X-rays, computed tomography, and lung ultrasound, play a crucial role in identifying PALI and assessing its severity. Pathophysiologically, PALI encompasses a spectrum of factors, including chest compression-related trauma, pulmonary IR injury, aspiration, and systemic inflammation, which collectively contribute to lung dysfunction and poor outcomes. Therapeutically, lung-protective ventilation strategies, such as low tidal volume ventilation and optimization of positive end-expiratory pressure, have emerged as cornerstone approaches in the management of PALI. Additionally, therapeutic hypothermia and emerging therapies targeting mitochondrial dysfunction hold promise in mitigating PALI-related morbidity and mortality.

CONCLUSION

PALI represents a significant clinical challenge in post-cardiac arrest care, necessitating prompt diagnosis and targeted interventions to improve outcomes. Mitochondrial-related therapies are among the novel therapeutic strategies for PALI. Further clinical research is warranted to optimize PALI management and enhance post-cardiac arrest care paradigms.

Protected cardiac surgery: strategic mechanical circulatory support to improve postcardiotomy mortality

PURPOSE OF REVIEW

To examine the evolving landscape of cardiac surgery, focusing on the increasing complexity of patients and the role of mechanical circulatory support (MCS) in managing perioperative low cardiac output syndrome (P-LCOS).

RECENT FINDINGS

P-LCOS is a significant predictor of mortality in cardiac surgery patients. Preoperative risk factors, such as cardiogenic shock and elevated lactate levels, can help identify those at higher risk. Proactive use of MCS, rather than reactive implementation after P-LCOS develops, may lead to improved outcomes by preventing severe organ hypoperfusion. The emerging concept of "protected cardiac surgery" emphasizes early identification of these high-risk patients and planned MCS utilization. Additionally, specific MCS strategies are being developed and refined for various cardiac conditions, including AMI-CS, valvular surgeries, and pulmonary thromboendarterectomy.

SUMMARY

This paper explores the shifting demographics and complexities in cardiac surgery patients. It emphasizes the importance of proactive, multidisciplinary approaches to identify high-risk patients and implement early MCS to prevent P-LCOS and improve outcomes. The concept of protected cardiac surgery, involving planned MCS use and shared decision-making, is highlighted. The paper also discusses MCS strategies tailored to specific cardiac procedures and the ethical considerations surrounding MCS implementation.

The impact of ECPELLA on haemodynamics and global oxygen delivery: a comprehensive simulation of biventricular failure

BACKGROUND

ECPELLA, a combination of veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) and Impella, a percutaneous left ventricular (LV) assist device, has emerged as a novel therapeutic option in patients with severe cardiogenic shock (CS). Since multiple cardiovascular and pump factors influence the haemodynamic effects of ECPELLA, optimising ECPELLA management remains challenging. In this study, we conducted a comprehensive simulation study of ECPELLA haemodynamics. We also simulated global oxygen delivery (DO2) under ECPELLA in severe CS and acute respiratory failure as a first step to incorporate global DO2 into our developed cardiovascular simulation.

METHODS AND RESULTS

Both the systemic and pulmonary circulations were modelled using a 5-element resistance‒capacitance network. The four ventricles were represented by time-varying elastances with unidirectional valves. In the scenarios of severe LV dysfunction, biventricular dysfunction with normal pulmonary vascular resistance (PVR, 0.8 Wood units), and biventricular dysfunction with high PVR (6.0 Wood units), we compared the changes in haemodynamics, pressure-volume relationship (PV loop), and global DO2 under different VA-ECMO flows and Impella support levels.

RESULTS

In the simulation, ECPELLA improved total systemic flow with a minimising biventricular pressure-volume loop, indicating biventricular unloading in normal PVR conditions. Meanwhile, increased Impella support level in high PVR conditions rendered the LV-PV loop smaller and induced LV suction in ECPELLA support conditions. The general trend of global DO2 was followed by the changes in total systemic flow. The addition of veno-venous ECMO (VV-ECMO) augmented the global DO2 increment under ECPELLA total support conditions.

CONCLUSIONS

The optimal ECPELLA support increased total systemic flow and achieved both biventricular unloading. The VV-ECMO effectively improves global DO2 in total ECPELLA support conditions.

ECMO in Myocardial Infarction-Associated Cardiogenic Shock: Blood Biomarkers as Predictors of Mortality

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation (va-ECMO) can provide circulatory and respiratory support in patients with cardiogenic shock. The main aim of this work was to investigate the association of blood biomarkers with mortality in patients with myocardial infarction needing va-ECMO support.

METHODS

We retrospectively analyzed electronic medical charts from patients receiving va-ECMO support in the period from 2008 to 2021 at the Medical University Innsbruck, Department of Anesthesiology and Intensive Care Medicine.

RESULTS

Of 188 patients, 57% (108/188) survived to discharge, with hemorrhage (46%) and thrombosis (27%) as the most frequent adverse events. Procalcitonin levels were markedly higher in non-survivors compared with survivors during the observation period. The multivariable model identified higher blood levels of procalcitonin (HR 1.01, p = 0.002) as a laboratory parameter associated with a higher risk of mortality.

CONCLUSIONS

In our study population of patients with myocardial infarction-associated cardiogenic shock, deceased patients had increased levels of inflammatory blood biomarkers throughout the whole study period. Increased procalcitonin levels have been associated with a higher risk of mortality. Future studies are needed to show the role of procalcitonin in patients receiving ECMO support.