Neurological outcome after extracorporeal cardiopulmonary resuscitation for in-hospital cardiac arrest: a systematic review and meta-analysis

Short-Term Neurologic Complications in Patients Undergoing Extracorporeal Membrane Oxygenation Support: A Review on Pathophysiology, Incidence, Risk Factors, and Outcomes

Regardless of the type, extracorporeal membrane oxygenation (ECMO) requires the use of large intravascular cannulas and results in multiple abnormalities including non-physiologic blood flow, hemodynamic perturbation, rapid changes in blood oxygen and carbon dioxide levels, coagulation abnormalities, and a significant systemic inflammatory response. Among other sequelae, neurologic complications are an important source of mortality and long-term morbidity. The frequency of neurologic complications varies and is likely underreported due to the high mortality rate. Neurologic complications in patients supported by ECMO include ischemic and hemorrhagic stroke, hypoxic brain injury, intracranial hemorrhage, and brain death. In addition to the disease process that necessitates ECMO, cannulation strategies and physiologic disturbances influence neurologic outcomes in this high-risk population. For example, the overall documented rate of neurologic complications in the venovenous ECMO population is lower, but a higher rate of intracranial hemorrhage exists. Meanwhile, in the venoarterial ECMO population, ischemia and global hypoperfusion seem to compose a higher percentage of neurologic complications. In what follows, the literature is reviewed to discuss the pathophysiology, incidence, risk factors, and outcomes related to short-term neurologic complications in patients supported by ECMO.

Extracorporeal Membrane Oxygenation Pathway for Management of Refractory Cardiac Arrest: a Retrospective Study From a National Center of Extracorporeal Cardiopulmonary Resuscitation

BACKGROUND

Cardiac arrest remains a critical condition with high mortality and catastrophic neurological impact. Extracorporeal cardiopulmonary resuscitation (ECPR) has been introduced as an adjunct in cardiopulmonary resuscitation modalities. However, survival with good neurological outcomes remains a major concern. This study aims to explore our early experience with ECPR and identify the factors associated with survival in patients presenting with refractory cardiac arrest.

METHODS

This is a retrospective cohort study analyzing 6-year data from a tertiary center, the country reference for ECPR. This study was conducted at a national center of ECPR. Participants of this study were adult patients who experienced witnessed refractory cardiopulmonary arrest and were supported by ECPR. ECPR was performed for eligible patients as per the local service protocols.

RESULTS

Data from 87 patients were analyzed; of this cohort, 62/87 patients presented with in-hospital cardiac arrest (IHCA) and 25/87 presented with out-of-hospital cardiac arrest (OHCA). Overall survival to decannulation and hospital discharge rates were 26.4% and 25.3%, respectively. Among survivors (n = 22), 19 presented with IHCA (30.6%), while only 3 survivors presented with OHCA (12%). A total of 15/87 (17%) patients were alive at 6-month follow-up. All survivors had good neurological function assessed as Cerebral Performance Category 1 or 2. Multivariate logistic regression to predict survival to hospital discharge showed that IHCA was the only independent predictor (odds ratio: 5.8, P = 0.042); however, this positive association disappeared after adjusting for the first left ventricular ejection fraction after resuscitation.

CONCLUSIONS

In this study, the use of ECPR for IHCA was associated with a higher survival to discharge compared to OHCA. This study demonstrated a comparable survival rate to other established centers, particularly for IHCA. Neurological outcomes were comparable in both IHCA and OHCA survivors. However, large multicenter studies are warranted for better understanding and improving the outcomes.

Comparison of prognosis between extracorporeal CPR and conventional CPR for patients in cardiac arrest: a systematic review and meta-analysis

AIM

Compared to the conventional cardiopulmonary resuscitation (CCPR), potential benefits of extracorporeal cardiopulmonary resuscitation (ECPR) for patients with cardiac arrest (CA) are still controversial. We aimed to determine whether ECPR can improve the prognosis of CA patients compared with CCPR.

METHODS

We systematically searched PubMed, EMBASE, and Cochrane Library from database's inception to July 2023 to identify randomized controlled trials (RCTs) or cohort studies that compared ECPR with CCPR in adults (aged ≥ 16 years) with out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA). This meta-analysis was performed using a random-effects model. Two researchers independently reviewed the relevance of the study, extracted data, and evaluated the quality of the included literature. The primary outcome was short-term (from hospital discharge to one month after cardiac arrest) and long-term (≥ 90 days after cardiac arrest) survival with favorable neurological status (defined as cerebral performance category scores 1 or 2). Secondary outcomes included survival at 1 months, 3-6 months, and 1 year after cardiac arrest.

RESULTS

The meta-analysis included 3 RCTs and 14 cohort studies involving 167,728 patients. We found that ECPR can significantly improve good neurological prognosis (RR 1.82, 95%CI 1.42-2.34, I2 = 41%) and survival rate (RR 1.51, 95%CI 1.20-1.89, I2 = 62%). In addition, the results showed that ECPR had different effects on favorable neurological status in patients with OHCA (short-term: RR 1.50, 95%CI 0.98- 2.29, I2 = 55%; long-term: RR 1.95, 95% CI 1.06-3.59, I2 = 11%). However, ECPR had significantly better effects on neurological status than CCPR in patients with IHCA (short-term: RR 2.18, 95%CI 1.24- 3.81, I2 = 9%; long-term: RR 2.17, 95% CI 1.19-3.94, I2 = 0%).

CONCLUSIONS

This meta-analysis indicated that ECPR had significantly better effects on good neurological prognosis and survival rate than CCPR, especially in patients with IHCA. However, more high-quality studies are needed to explore the role of ECPR in patients with OHCA.

Predictors and Outcomes of Acute Brain Injury in Patients on Venoarterial Extracorporeal Membrane Oxygenation after Cardiopulmonary Resuscitation

Background

Venoarterial (V-A) extracorporeal membrane oxygenation (ECMO) after cardiac arrest often predisposes patients to acute brain injury (ABI), which affects survival and neurological performance. The investigation of the predictors of ABI will be beneficial for further management.

Objectives

To explore the predictors and outcomes of ABI and intracerebral hemorrhage (ICH) in patients experiencing cardiac arrest and cardiopulmonary resuscitation (CPR) with V-A ECMO support.

Methods

We retrospectively analyzed 150 patients who successfully weaned from V-A ECMO support after pre-ECMO CPR at our institution from January 2009 to December 2021. Short-term and long-term outcomes were evaluated. Characteristics before and during ECMO were analyzed for determining the predictors of ABI and ICH.

Results

Of the 150 patients, 66 (44.0%) had ABI. ABI was associated with higher in-hospital mortality (62.1% vs. 21.4%, p < 0.0001) and poorer long-term survival after discharge (p = 0.002). Patients who survived to discharge with ABI had significantly more severe neurological deficits at discharge (84.0% vs. 42.4%, p < 0.0001) and improved little at one year after discharge (33.3% vs. 11.4%, p = 0.027). We found that CPR duration [odds ratio (OR) = 1.04, p = 0.003] was the independent risk factor for ABI, whereas lower platelet counts was the independent risk factor for ICH (OR = 0.96, p = 0.019).

Conclusions

After CPR, development of ABI during V-A ECMO support impacted survival and further neurological outcome. Longer CPR duration before ECMO set up significantly increases the occurrence of ABI. Besides, severe thrombocytopenia during ECMO support increases the possibility of ICH.

Machine learning-based predictor for neurologic outcomes in patients undergoing extracorporeal cardiopulmonary resuscitation

Background

We investigated the predictors of poor neurological outcomes in extracorporeal cardiopulmonary resuscitation (ECPR) patients using machine learning (ML) approaches.

Methods

This study was a retrospective, single-center, observational study that included adult patients who underwent ECPR while hospitalized between January 2010 and December 2020. The primary outcome was neurologic status at hospital discharge as assessed by the Cerebral Performance Categories (CPC) score (scores range from 1 to 5). We trained and tested eight ML algorithms for a binary classification task involving the neurological outcomes of survivors after ECPR.

Results

During the study period, 330 patients were finally enrolled in this analysis; 143 (43.3%) had favorable neurological outcomes (CPC score 1 and 2) but 187 (56.7%) did not. From the eight ML algorithms initially considered, we refined our analysis to focus on the three algorithms, eXtreme Gradient Boosting, random forest, and Stochastic Gradient Boosting, that exhibited the highest accuracy. eXtreme Gradient Boosting models exhibited the highest accuracy among all the machine learning algorithms (accuracy: 0.739, area under the curve: 0.837, Kappa: 0.450, sensitivity: 0.700, specificity: 0.740). Across all three ML models, mean blood pressure emerged as the most influential variable, followed by initial serum lactate, and arrest to extracorporeal membrane oxygenation (ECMO) pump-on-time as important predictors in machine learning models for poor neurological outcomes following successful ECPR.

Conclusions

In conclusion, machine learning methods showcased outstanding predictive accuracy for poor neurological outcomes in patients who underwent ECPR.

Extracorporeal membrane oxygenation for critically ill adults

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) may provide benefit in certain populations of adults, including those with severe cardiac failure, severe respiratory failure, and cardiac arrest. However, it is also associated with serious short- and long-term complications, and there remains a lack of high-quality evidence to guide practice. Recently several large randomized controlled trials (RCTs) have been published, therefore, we undertook an update of our previous systematic review published in 2014.

OBJECTIVES

To evaluate whether venovenous (VV), venoarterial (VA), or ECMO cardiopulmonary resuscitation (ECPR) improve mortality compared to conventional cardiopulmonary support in critically ill adults.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was March 2022. The search was limited to English language only.

SELECTION CRITERIA

We included RCTs, quasi-RCTs, and cluster-RCTs that compared VV ECMO, VA ECMO or ECPR to conventional support in critically ill adults.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcome was 1. all-cause mortality at day 90 to one year. Our secondary outcomes were 2. length of hospital stay, 3. survival to discharge, 4. disability, 5. adverse outcomes/safety events, 6. health-related quality of life, 7. longer-term health status, and 8. cost-effectiveness. We used GRADE to assess certainty of evidence.

MAIN RESULTS

Five RCTs met our inclusion criteria, with four new studies being added to the original review (total 757 participants). Two studies were of VV ECMO (429 participants), one VA ECMO (41 participants), and two ECPR (285 participants). Four RCTs had a low risk of bias and one was unclear, and the overall certainty of the results (GRADE score) was moderate, reduced primarily due to indirectness of the study populations and interventions. ECMO was associated with a reduction in 90-day to one-year mortality compared to conventional treatment (risk ratio [RR] 0.80, 95% confidence interval [CI] 0.70 to 0.92; P = 0.002, I2 = 11%). This finding remained stable after performing a sensitivity analysis by removing the single trial with an uncertain risk of bias. Subgroup analyses did not reveal a significant subgroup effect across VV, VA, or ECPR modes (P = 0.73). Four studies reported an increased risk of major hemorrhage with ECMO (RR 3.32, 95% CI 1.90 to 5.82; P < 0.001), while two studies reported no difference in favorable neurologic outcome (RR 2.83, 95% CI 0.36 to 22.42; P = 0.32). Other secondary outcomes were not consistently reported across the studies.

AUTHORS' CONCLUSIONS

In this updated systematic review, which included four additional RCTs, we found that ECMO was associated with a reduction in day-90 to one-year all-cause mortality, as well as three times increased risk of bleeding. However, the certainty of this result was only low to moderate, limited by a low number of small trials, clinical heterogeneity, and indirectness across studies.

Long-term outcomes and prognostic factors of extracorporeal cardiopulmonary resuscitation in patients older than 75 years: a single-centre retrospective study

BACKGROUND

Few studies have assessed older adult patients who received extracorporeal cardiopulmonary resuscitation (ECPR) after cardiac arrest, and outcomes and prognostic factors of ECPR in this population remain unclear. This study aimed to assess the long-term outcomes and prognostic factors among patients older than 75 years who received ECPR after experiencing cardiac arrest.

METHODS

This is a single-centre, retrospective case-control study conducted between August 2010 and July 2019. Consecutive patients older than 75 years who had in-hospital (IHCA) or out-of-hospital cardiac arrest (OHCA) and received ECPR at the Emergency Department in the Hyogo Emergency Medical Center, Hyogo, Japan, were included. The primary outcome was a favourable neurological outcome, defined as a Cerebral Performance Category score of 1-2 at 1 year after the event. Univariate logistic regression was used to determine the association between variables and patient outcomes.

RESULTS

Of the 187 patients with cardiac arrest who received ECPR, 30 were older than 75 years and 28 (15% of the cohort receiving ECPR) were examined in this study. The median age of the patients was 79 years (IQR 77-82), and there were 13 (46%) male patients. Neurological outcomes were favourable for seven (25%) patients, five of whom had IHCA and two with out-of-hospital OHCA. On univariate analysis, patients with a favourable outcome had a shorter median total collapse time (TCT) than those with an unfavourable outcome (favourable: 18.0 min (IQR 13.0-33.5) vs unfavourable: 44.0 min (IQR 25.0-53.0); p=0.049).

CONCLUSION

In selected patients older than 75 years, ECPR could be beneficial by providing a shorter TCT, which may contribute to favourable neurological outcomes. Nevertheless, further studies are needed to validate these findings.

The effects of ECMO on neurological function recovery of critical patients: A double-edged sword

Extracorporeal membrane oxygenation (ECMO) played an important role in the treatment of patients with critical care such as cardiac arrest (CA) and acute respiratory distress syndrome. ECMO is gradually showing its advantages in terms of speed and effectiveness of circulatory support, as it provides adequate cerebral blood flow (CBF) to the patient and ensures the perfusion of organs. ECMO enhances patient survival and improves their neurological prognosis. However, ECMO-related brain complications are also important because of the high risk of death and the associated poor outcomes. We summarized the reported complications related to ECMO for patients with CA, such as north–south syndrome, hypoxic–ischemic brain injury, cerebral ischemia–reperfusion injury, impaired intracranial vascular autoregulation, embolic stroke, intracranial hemorrhage, and brain death. The exact mechanism of ECMO on the role of brain function is unclear. Here we review the pathophysiological mechanisms associated with ECMO in the protection of neurologic function in recent years, as well as the ECMO-related complications in brain and the means to improve it, to provide ideas for the treatment of brain function protection in CA patients.

Clinician Perspectives on Cannulation for Extracorporeal Cardiopulmonary Resuscitation: A Mixed Methods Analysis

Out-of-hospital cardiac arrest is a leading cause of mortality with survival rates of less than 10%. In selected patients, survival may be improved via timely application of extracorporeal cardiopulmonary resuscitation (ECPR). However, ECPR is a complex and resource intensive intervention with a high risk of complications that impair widespread clinical adoption. This study employed a mixed approach of qualitative interview analysis embedded with quantitative data collection to uncover the major hurdles faced by clinicians during ECPR initiation. We conducted semi-structured interviews with eight ECPR intensive care specialists with 2-10 years of experience working at a large, tertiary ECPR center in Australia. Clinicians identified dilation as the most time-consuming step, followed by draping, and decision-making during extracorporeal membrane oxygenation patient selection. The most challenging step was the decision-making for patient selection, followed by dilation and imaging. These findings uncovered key barriers to ECPR, and identified priority areas for further research and clinical training. Major logistical hindrances will require well-defined protocols and improved clinical training. Engineering innovations in the identified areas may improve the delivery of ECPR, making it simpler and faster to deliver.

Extracorporeal cardiopulmonary resuscitation (eCPR) and cerebral perfusion: A narrative review

Extracorporeal cardiopulmonary resuscitation (eCPR) is emerging as an effective, lifesaving resuscitation strategy for select patients with prolonged or refractory cardiac arrest. Currently, a paucity of evidence-based recommendations is available to guide clinical management of eCPR patients. Despite promising results from initial clinical trials, neurological injury remains a significant cause of morbidity and mortality. Neuropathology associated with utilization of an extracorporeal circuit may interact significantly with the consequences of a prolonged low-flow state that typically precedes eCPR. In this narrative review, we explore current gaps in knowledge about cerebral perfusion over the course of cardiac arrest and resuscitation with a focus on patients treated with eCPR. We found no studies which investigated regional cerebral blood flow or cerebral autoregulation in human cohorts specific to eCPR. Studies which assessed cerebral perfusion in clinical eCPR were small and limited to near-infrared spectroscopy. Furthermore, no studies prospectively or retrospectively evaluated the relationship between epinephrine and neurological outcomes in eCPR patients. In summary, the field currently lacks a comprehensive understanding of how regional cerebral perfusion and cerebral autoregulation are temporally modified by factors such as pre-eCPR low-flow duration, vasopressors, and circuit flow rate. Elucidating these critical relationships may inform future strategies aimed at improving neurological outcomes in patients treated with lifesaving eCPR.

Outcomes of Patients With in- and out-of-hospital Cardiac Arrest on Extracorporeal Cardiopulmonary Resuscitation: A Single-center Retrospective Cohort Study

Extracorporeal membrane oxygenation (ECMO) support has been suggested to improve the survival rate in patients with refractory in- and out-of-hospital cardiac arrest (IHCA and OHCA). Several factors predict outcome in these patients, including initial heart rhythm and low-flow time. Literature shows variable survival rates among patients who received extracorporeal cardiopulmonary resuscitation (EPCR). The objective of this study is to analyze the outcomes (survival rate as well as neurological and disability outcomes) of patients treated with ECPR following refractory OHCA and IHCA. This single-center, retrospective cohort study was conducted on patients with refractory cardiac arrest treated with ECPR between February 2016 and March 2020. The primary outcomes were 24-hour, hospital discharge and 1-year survival after CA and the secondary endpoints were neurological and disability outcomes. Forty-eight patients were included in the analysis. 11/48 patients are In Hospital Cardiac Arrest (IHCA) and 37/48 patients are Out of Hospital Cardiac Arrest (OHCA). Time from collapse to CPR for 79.2% of the patients was less than 5 minutes. The median CPR duration and collapse to ECMO were 40 and 45 minutes, respectively. The rate of survival was significantly higher in patient who presented with initial shockable rhythm (P = 0.006) and to whom targeted temperature management (TTM) post cardiac arrest was applied (P = 0.048). This first descriptive study about ECPR in the middle east region shows that 20.8% of ECPR patients survived until hospital discharge. Our analysis revealed that initial shockable rhythm and TTM are most important prognostic factors that predicts favorable neurological survival.

Extracorporeal cardiopulmonary resuscitation in adults and children: A review of literature, published guidelines and pediatric single-center program building experience

Extracorporeal cardiopulmonary resuscitation (ECPR) is an adjunct supportive therapy to conventional cardiopulmonary resuscitation (CCPR) employing veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in the setting of refractory cardiac arrest. Its use has seen a significant increase in the past decade, providing hope for good functional recovery to patients with cardiac arrest refractory to conventional resuscitation maneuvers. This review paper aims to summarize key findings from the ECPR literature available to date as well as the recommendations for ECPR set forth by leading national and international resuscitation societies. Additionally, we describe the successful pediatric ECPR program at Texas Children's Hospital, highlighting the logistical, technical and educational features of the program.

Prognostic significance of the blood urea nitrogen to creatinine ratio in in-hospital cardiac arrest after targeted temperature management

BACKGROUND

Targeted temperature management (TTM) has been reported to improve outcomes in in-hospital cardiac arrest (IHCA) patients but little has been investigated into the relationship between prognoses and the blood urea nitrogen to creatinine ratio (BCR).

METHODS

A retrospective analysis of data from IHCA survivors treated with TTM between 2011 and 2018 was conducted based on the Research Patient Database Registry of the Partners HealthCare system in Boston. Serum laboratory data were measured during IHCA and within 24 hours after TTM completion. Intra-arrest and post-TTM BCRs were calculated, respectively. The primary outcome was neurologic status at discharge. The secondary outcome was in-hospital mortality.

RESULTS

The study included 84 patients; 63 (75%) were discharged with a poor neurologic status and 40 (47.6%) died. Regarding poor neurological outcome at discharge, multivariate analysis revealed that post-TTM BCR was a significant predictor (adjusted OR, 1.081; 95% CI, 1.002-1.165; p = 0.043) and intra-arrest BCR was a marginal predictor (adjusted OR, 1.067; 95% CI, 1.000-1.138; p = 0.050). Post-TTM BCR had an acceptably predictive ability to discriminate neurological status at discharge, with an area under the receiver-operating characteristic curve of 0.644 (95% CI, 0.516-0.773) and a post-TTM BCR cutoff value of 16.7 had a sensitivity of 61.9% and a specificity of 70.0%.

CONCLUSION

Post-TTM BCR was a significant predictor of the neurologic outcome at discharge among IHCA patients receiving TTM. IHCA patients with elevated intra-arrest BCR also had a borderline poor neurological prognosis at discharge.

Quality of life and functional outcomes after in-hospital cardiopulmonary resuscitation. A systematic review

AIM

Our aim was to determine the association of cardiopulmonary resuscitation (CPR) for in hospital cardiac arrest (IHCA) with quality of life after discharge.

METHODS

We performed a systematic review using available databases for studies that measured any quality-of-life or functional outcome both before and after CPR for IHCA. All screening and data abstraction was performed in duplicate.

RESULTS

We screened 10,927 records and included 24 papers representing 20 unique studies. Fifteen studies measured Cerebral Performance Category. Survival ranged from 11.8% to 39.5%. The risk of impaired cerebral function after discharged ranged from -16.1% (lower risk) to 44.7% increased risk of poor cerebral function after surviving to discharge. Four studies measured discharge to an institutional environment finding that the risk was increased by 18.2-72.2% among survivors. One study measured EQ-5D and found no difference pre and post CPR. One study measured performance of activities of daily living finding that survivors needed assistance with more activities after discharge.

CONCLUSION

Our review is limited by the lack of adjustment for confounders, including the baseline level of each outcome, in all included studies. Therefore, although risk for most outcomes was increased after discharge vs pre-admission we cannot be certain if this is a causal relationship.

Extrakorporale Reanimation – Kriterien, Bedingungen, Outcome

Für ausgewählte Patienten, in denen die konventionelle kardiopulmonale Reanimation (cCPR) erfolglos bleibt, sprechen die europäischen Leitlinien zur Reanimation 2021 erstmals eine Empfehlung zur extrakorporalen Reanimation (eCPR) als mögliche Rettungstherapie aus. Die eCPR wird im therapierefraktären Kreislaufstillstand etabliert, um Diagnostik und Therapie reversibler Ursachen, wie Herzinfarkt, Lungenembolie, akzidentielle Hypothermie, Intoxikationen mit herzwirksamen Substanzen und akute Hypoxie, zu ermöglichen. Selektionskriterien für eCPR umfassen prognostische Reanimationsfaktoren, wie beobachteter Kreislaufstillstand, Start von Reanimationsmaßnahmen in < 5 min, schockbarer Erstrhythmus, Zeichen effektiver cCPR wie Lebenszeichen während der Reanimation, anhaltendes Kammerflimmern, intermittierende Phasen von Spontankreislauf oder anhaltendes endtidales CO₂ > 10 mm Hg, Patientenalter und Gesundheitszustand. Die Zeitspanne vom Kreislaufstillstand bis zur eCPR ist eine der wichtigsten Determinanten für neurologisch gutes Überleben und sollte < 60 min liegen. Für die Einhaltung dieser Zielvorgabe muss eine entschlossene „Load-and-Go“-Strategie mit frühzeitiger Patientenselektion und raschem Transport unter mechanischer cCPR in ein eCPR-Zentrum verfolgt werden, oder es wird versucht, die eCPR präklinisch zum Einsatz zu bringen. Zwei randomisierte kontrollierte eCPR-Studien demonstrierten Überlebensraten von 43 % bzw. 31,5 % bei Patienten mit anhaltendem Kammerflimmern bzw. kardialem Kreislaufstillstand. Ob diese Ergebnisse außerhalb einzelner hochspezialisierter Zentren anwendbar sind, ist wie die Frage nach der besten präklinischen und innerklinischen Strategie Gegenstand zukünftiger Studien.

Can Cardiopulmonary Rehabilitation Facilitate Weaning of Extracorporeal Membrane Oxygenation (CaRe-ECMO)? Study Protocol for a Prospective Multidisciplinary Randomized Controlled Trial

Background: Mortality of patients suffering from critical illness has been dramatically improved with advanced technological development of extracorporeal membrane oxygenation (ECMO) therapy. However, the majority of ECMO-supported patients failed to wean from ECMO therapy. As one of several options, cardiopulmonary rehabilitation serves as effective intervention in the improvement of cardiovascular and respiratory function in various major critical illness. Nonetheless, its role in facilitating ECMO weaning has not yet been explored. The purpose of this study is to investigate the effectiveness of cardiopulmonary rehabilitation on rate of ready for ECMO weaning in ECMO-supported patients (CaRe-ECMO).

Methods: The CaRe-ECMO trial is a randomized controlled, parallel group, clinical trial. This trial will be performed in a minimum number of 366 ECMO-supported eligible patients. Patients will be randomly assigned to either: (1) the CaRe-ECMO group, which will be treated with usual care including pharmacotherapy, non-pharmacotherapy, and specific nursing for ECMO therapy and the CaRe-ECMO program; or (2) the control group, which will receive usual care only. The CaRe-ECMO program consists of protocolized positioning, passive range of motion (PROM) training, neuromuscular electrical stimulation (NMES), surface electrical phrenic nerve stimulation (SEPNS), and pulmonary rehabilitation. The primary outcome of the CaRe-ECMO trial is the rate of ready for ECMO weaning at CaRe-ECMO day 7 (refers to 7 days after the CaRe-ECMO program initiation). Secondary outcomes include rate of ECMO and mechanical ventilation weaning, total length in day of ready for ECMO weaning, ECMO weaning and mechanical ventilation, all-cause mortality, rate of major post-ECMO complications, ECMO unit length of stay (LOS) and hospital LOS, total cost for hospitalization, cerebral performance category (CPC), activities of daily living (ADL), and health-related quality of life (HRQoL).

Discussion: The CaRe-ECMO is designed to answer the question “whether cardiopulmonary rehabilitation can facilitate weaning of ECMO (CaRe-ECMO).” Should the implementation of the CaRe-ECMO program result in superior primary and secondary outcomes as compared to the controls, specifically the add-on effects of cardiopulmonary rehabilitation to the routine ECMO practice for facilitating successful weaning, the CaRe-ECMO trial will offer an innovative treatment option for ECMO-supported patients and meaningfully impact on the standard care in ECMO therapy.

Clinical Trial Registration:ClinicalTrials.gov, identifier: NCT05035797.

Extracorporeal life support in adult patients with out-of-hospital cardiac arrest

The use of extracorporeal life support in cardiopulmonary resuscitation (CPR) of adult patients experiencing out-of-hospital cardiac arrest by the application of veno-arterial extracorporeal membrane oxygenation (ECMO) during cardiac arrest has been increasing over the past decade. This can be attributed to the encouraging results of extracorporeal CPR (ECPR) in multiple observational studies. To date, only one randomised controlled trial has compared ECPR to conventional advanced life support measures. Patient selection is crucial for the success of ECPR programmes. A rapid and organised approach is required for resuscitation, i.e. cannula insertion with ECMO pump initiation in combination with other aspects of post-cardiac arrest care such as targeted temperature management and early coronary reperfusion. The provision of an ECPR service can be costly, resource intensive and technically challenging, as limited studies have reported on its cost-effectiveness.

Extracorporeal cardiopulmonary resuscitation for refractory in-hospital cardiac arrest: A retrospective cohort study

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is a rescue therapy for refractory cardiac arrest, but its high mortality has raised questions about patient selection. No selection criteria have been proposed for patients experiencing in-hospital cardiac arrest. We aimed to identify selection criteria available at the time ECPR was considered for patients with in-hospital cardiac arrest. We analyzed data of in-hospital cardiac arrest patients undergoing ECPR in our extracorporeal membrane oxygenation (ECMO) center (March 2007 to March 2019). Intensive care unit (ICU) and 1-year survival post-hospital discharge were assessed. Factors associated with ICU survival before ECPR were investigated. An external validation cohort from a previous multicenter study was used to validate our results.

RESULTS

Among the 137 patients (67.9% men; median [IQR] age, 54 [43-62] years; low-flow duration, 45 [30-70] min) requiring ECPR, 32.1% were weaned-off ECMO. Their respective ICU- and 1-year survival rates were 21.9% and 19%. Most 1-year survivors had favorable neurological outcomes (cerebral performance category score 1 or 2). ICU survivors compared to nonsurvivors, respectively, were more likely to have a shockable initial rhythm (53.3% versus 24.3%; P < 0.01), a shorter median (IQR) low-flow time (30 (25-53) versus 50 (35-80) min, P < 0.01) and they more frequently underwent a subsequent intervention (63.3% versus 26.2%, P < 0.01). The algorithm obtained by combining age, initial rhythm and low-flow duration discriminated between patient groups with very different survival probabilities in the derivation and validation cohorts.

CONCLUSION

Survival of ECPR-managed in-hospital cardiac arrest patients in this cohort was poor but hospital survivors' 1-year neurological outcomes were favorable. When deciding whether or not to use ECPR, the combination of age, initial rhythm and low-flow duration can improve patient selection.

Predictors of Favorable Neurologic Outcomes in a Territory-First Extracorporeal Cardiopulmonary Resuscitation Program

Extracorporeal cardiopulmonary resuscitation (ECPR) is an advanced resuscitation method that has been associated with better outcomes after cardiac arrest compared with conventional cardiopulmonary resuscitation. This is a retrospective analysis of all patients who received ECPR for cardiac arrest in Hong Kong's first ECPR program from 2012 to 2020. The primary outcome was favorable neurologic outcome at 3 months. A new risk prediction model was developed and its performance was compared with published risk scores. One-hundred two patients received ECPR and 19 (18.6%) patients survived with favorable neurologic outcome. Having a shockable rhythm was the strongest predictor of favorable neurologic outcome in multivariate analysis (odds ratio, 9.64; 95% confidence interval [CI], 1.49 to 62.30; P = 0.017). We developed a simple model with three parameters for the prediction of favorable neurologic outcomes - presence of shockable rhythm, mean arterial pressure after extracorporeal membrane oxygenation, and the Acute Physiology And Chronic Health Evaluation IV score, with an area under receiver operating characteristic curve of 0.85 (95% CI, 0.77 to 0.94). In Hong Kong's first ECPR program, 18.6% patients survived with favorable neurologic outcomes, and having a shockable rhythm at presentation was the strongest predictor. Risk scores are useful in predicting important patient outcomes and should be included in clinical decision-making for patients who received ECPR.

Survival and Outcomes After Cardiac Arrest With VA-ECMO Rescue Therapy

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) use in patients with cardiac arrest is increasing. Utilization remains variable between centers using ECMO as a rescue therapy or early protocolized extracorporeal cardiopulmonary resuscitation.

METHODS

Single-center, retrospective evaluation of cardiac arrest with cardiopulmonary resuscitation and rescue ECMO support from 2011 through 2019. Study objectives included survival, non-neurologic, and neurologic outcomes; validation of the SAVE and modified SAVE (mSAVE) scores for survival and favorable neurologic outcome; and predictive factor identification in cardiac arrest with ECMO rescue therapy.

RESULTS

Eighty-nine patients were included. In-hospital survival was 38.2% and median CPC score was 2. Survivors had lower BMI (27.9 ± 4.2 kg/m2 vs. 32.3 ± 7.5 kg/m2, P = 0.003), less obesity (BMI ≥ 30 kg/m2) (26.5% vs. 49.1%, P = 0.035), shorter CPR duration (35.5 ± 31.7 m vs. 58.0 ± 49.5 m, P = 0.019), more tracheostomy (38.2% vs. 7.3%, P < 0.001), and less renal replacement therapy (RRT) (17.6% vs. 38.2%, P = 0.031). Patients with a favorable neurologic outcome had lower body weight (86.2 ± 17.9 kg vs. 98.1 ± 19.4 kg, P = 0.010), lower BMI (28.1 ± 4.5 kg/m2 vs. 33.9 ± 7.9 kg/m2, P < 0.001), and less obesity (29.7% vs. 56.3%, P = 0.026). mSAVE score predicted in-hospital survival (OR 1.11; 95%CI 1.03-1.19; P = 0.004) and favorable neurologic outcome (OR 1.11; 1.03-1.20; P = 0.009). Multivariate analysis for in-hospital survival included mSAVE, BMI, CPR-time, tracheostomy, and RRT (c-statistic: 0.864). Favorable neurologic outcome included mSAVE and BMI (c-statistic: 0.805).

CONCLUSIONS

mSAVE, BMI, RRT, and tracheostomy are predictors of in-hospital survival and mSAVE and BMI are predictors of favorable neurologic outcome in cardiac arrest with ECMO rescue therapy.

Extracorporeal cardiopulmonary resuscitation in-hospital cardiac arrest due to acute coronary syndrome

Background

The aim of this study was to analyze the effect of extracorporeal cardiopulmonary resuscitation on survival and neurological outcomes in in-hospital cardiac arrest patients.

Methods

Between January 2018 and December 2020, a total of 22 patients (17 males, 5 females; mean age: 52.8±9.0 years; range, 32 to 70 years) treated with extracorporeal cardiopulmonary resuscitation using veno-arterial extracorporeal membrane oxygenation support for in-hospital cardiac arrest after acute coronary syndrome were retrospectively analyzed. The patients were divided into two groups as those weaned (n=13) and non-weaned (n=9) from the veno-arterial extracorporeal membrane oxygenation. Demographic data of the patients, heart rhythms at the beginning of conventional cardiopulmonary resuscitation, the angiographic and interventional results, survival and neurological outcomes of the patients before and after extracorporeal cardiopulmonary resuscitation were recorded.

Results

There was no significant difference between the groups in terms of comorbidity and baseline laboratory test values. The underlying rhythm was ventricular fibrillation in 92% of the patients in the weaned group and there was no cardiac rhythm in 67% of the patients in the non-weaned group (p=0.125). The recovery in the mean left ventricular ejection fraction was significantly evident in the weaned group (36.5±12.7% vs. 21.1±7.4%, respectively; p=0.004). The overall wean rate from veno-arterial extracorporeal membrane oxygenation was 59.1%; however, the discharge rate from hospital of survivors without any neurological sequelae was 36.4%.

Conclusion

In-hospital cardiac arrest is a critical emergency situation requiring instantly life-saving interventions through conventional cardiopulmonary resuscitation. If it fails, extracorporeal cardiopulmonary resuscitation should be initiated, regardless the underlying etiology or rhythm disturbances. An effective conventional cardiopulmonary resuscitation is mandatory to prevent brain and body hypoperfusion.