Prognostic factors for extracorporeal cardiopulmonary resuscitation recipients following out-of-hospital refractory cardiac arrest. A systematic review and meta-analysis

Does extracorporeal cardiopulmonary resuscitation improve survival with favorable neurological outcome in out-of-hospital cardiac arrest? A systematic review and meta-analysis

PURPOSE

Extracorporeal cardiopulmonary resuscitation (E-CPR) may improve survival with favorable neurological outcome in patients with refractory out-of-hospital cardiac arrest (OHCA). Unfortunately, recent results from randomized controlled trials were inconclusive. We performed a meta-analysis to investigate the impact of E-CPR on neurological outcome compared to conventional cardiopulmonary resuscitation (C-CPR).

METHODS

A systematic research for articles assessing outcomes of adult patients with OHCA either treated with E-CPR or C-CPR up to April 27, 2023 was performed. Primary outcome was survival with favorable neurological outcome at discharge or 30 days. Overall survival was also assessed.

RESULTS

Eighteen studies were included. E-CPR was associated with better survival with favorable neurological status at discharge or 30 days (14% vs 7%, OR 2.35, 95% CI 1.61-3.43, I2 = 80%, p < 0.001, NNT = 17) than C-CPR. Results were consistent if the analysis was restricted to RCTs. Overall survival to discharge or 30 days was also positively affected by treatment with E-CPR (OR = 1.71, 95% CI = 1.18-2.46, I2 = 81%, p = 0.004, NNT = 11).

CONCLUSIONS

In this meta-analysis, E-CPR had a positive effect on survival with favorable neurological outcome and, to a smaller extent, on overall mortality in patients with refractory OHCA.

The ABC (Age, Bystander, and Cardiogram) score for predicting neurological outcomes of cardiac arrests without pre-hospital return of spontaneous circulation: A nationwide population-based study

Aim

We previously proposed the ABC score to predict the neurological outcomes of cardiac arrest without prehospital return of spontaneous circulation (ROSC). Using nationwide population-based data, this study aimed to validate the ABC score through various resuscitation guideline periods.

Methods

We analysed cases with cardiac arrest due to internal causes and failure to achieve prehospital ROSC in the All-Japan Utstein Registry. Patients from the 2007-2009, 2012-2014, and 2017-2019 periods were classified into the 2005, 2010, and 2015 guideline groups, respectively. Neurological outcomes were assessed using cerebral performance categories (CPCs) one month after the cardiac arrest. We defined CPC 1-2 as a favourable outcome. We evaluated the test characteristics of the ABC score, which could range from 0 to 3.

Results

Among the 162,710, 186,228, and 190,794 patients in the 2005, 2010, and 2015 guideline groups, 0.7%, 0.8%, and 0.9% of the patients had CPC 1-2, respectively. The proportions of CPC 1-2 were 2.9%, 3.6%, and 4.6% in patients with ABC scores of 2 and were 9.5%, 13.3%, and 16.8% in patients with ABC scores of 3, respectively. Among patients with ABC scores of 0, 0.2%, 0.1%, and 0.2%, all had CPC 1-2, respectively. The areas under the receiver operating characteristic curves for the ABC score were 0.798, 0.822, and 0.828, respectively.

Conclusions

The ABC score had acceptable discrimination for neurological outcomes in patients without prehospital ROSC in the three guideline periods.

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.

Adenosine 2A Receptor Agonism Improves Survival in Extracorporeal Cardiopulmonary Resuscitation

INTRODUCTION

Despite resuscitation advances including extracorporeal cardiopulmonary resuscitation (ECPR), freedom from neurologic and myocardial insult after cardiac arrest remains unlikely. We hypothesized that adenosine 2A receptor (A2AR) agonism, which attenuates reperfusion injury, would improve outcomes in a porcine model of ECPR.

METHODS

Adult swine underwent 20 min of circulatory arrest followed by defibrillation and 6 h of ECPR. Animals were randomized to receive saline vehicle or A2AR agonist (ATL1223 or Regadenoson) infusion during extracorporeal membrane oxygenation. Animals were weaned off extracorporeal membrane oxygenation and monitored for 24 h. Clinical and biochemical end points were compared.

RESULTS

The administration of A2AR agonists increased survival (P = 0.01) after cardiac arrest compared to vehicle. Markers of neurologic damage including S100 calcium binding protein B and glial fibrillary acidic protein were significantly lower with A2AR agonist treatment.

CONCLUSIONS

In a model of cardiac arrest treated with ECPR, A2AR agonism increased survival at 24 h and reduced neurologic damage suggesting A2AR activation may be a promising therapeutic target after cardiac arrest.

Differences in outcomes of patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation between day-time and night-time

Although patients who underwent night-time resuscitation for out-of-hospital cardiac arrest (OHCA) had worse clinical outcomes than those who underwent day-time resuscitation, the differences between the outcomes of patients with OHCA who underwent extracorporeal cardiopulmonary resuscitation (ECPR) in the day-time and night-time remain unclear. We analyzed data from the Study of Advanced Life Support for Ventricular Fibrillation with Extracorporeal Circulation in Japan. Patients were categorized according to whether they received treatment during the day-time or night-time. The primary outcomes were survival to hospital discharge and favorable neurological outcome at discharge, and the secondary outcomes were estimated low-flow time, implementation time of ECPR, and complications due to ECPR. A multivariate logistic regression model adjusted for confounders was used for comparison. Among the 1644 patients, the night-time patients had a significantly longer ECMO implementation time and estimated low-flow time than the day-time patients, along with a significantly higher number of complications than the day-time patients. However, the survival and neurologically favorable survival rates did not differ significantly between the groups. Thus, although patients who underwent ECPR at night had an increased risk of longer implementation time and complications, their clinical outcomes did not differ from those who underwent day-time ECPR.

Impact of Lactate Clearance on Clinical and Neurological Outcomes of Patients With Out-of-Hospital Cardiac Arrest Treated With Extracorporeal Cardiopulmonary Resuscitation: A Secondary Data Analysis

OBJECTIVES

Serial evaluations of lactate concentration may be more useful in predicting outcomes in patients with out-of-hospital cardiac arrest (OHCA) than a single measurement. This study aimed to evaluate the impact of lactate clearance (LC) on clinical and neurologic outcomes in patients with OHCA who underwent extracorporeal cardiopulmonary resuscitation (ECPR).

DESIGN

Retrospective multicenter observational study.

SETTING

Patients with OHCA receiving ECPR at 36 hospitals in Japan between January 1, 2013, and December 31, 2018.

PATIENTS

This study evaluated 1227 patients, with lactate initial assessed upon emergency department admission and lactate second measured subsequently. To adjust for the disparity in the time between lactate measurements, the modified 6-hour LC was defined as follows: ([lactate initial -lactate second ]/lactate initial ) × 100 × (6/the duration between the initial and second measurements [hr]). The patients were divided into four groups according to the modified 6-hour LC with an equivalent number of patients among LC quartiles: Q1 (LC < 18.8), Q2 (18.8 < LC < 59.9), Q3 (60.0 < LC < 101.2), and Q4 (101.2 < LC).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The 30-day survival rates increased as the 6-hour LC increased (Q1, 21.2%; Q2, 36.8%; Q3, 41.4%; Q4, 53.6%; p for trend < 0.001). In the multivariate analysis, the modified 6-hour LC was significantly associated with a 30-day survival rate (adjusted odds ratio [AOR], 1.003; 95% CI, 1.001-1.005; p < 0.001) and favorable neurologic outcome (AOR, 1.002; 95% CI, 1.000-1.004; p = 0.027).

CONCLUSIONS

In patients with OHCA who underwent ECPR, an increase in the modified 6-hour LC was associated with favorable clinical and neurologic outcome. Thus, LC can be a criterion to assess whether ECPR should be continued.

Machine Learning Identifies Higher Survival Profile In Extracorporeal Cardiopulmonary Resuscitation

OBJECTIVES

Extracorporeal cardiopulmonary resuscitation (ECPR) has been shown to improve neurologically favorable survival in patients with refractory out-of-hospital cardiac arrest (OHCA) caused by shockable rhythms. Further refinement of patient selection is needed to focus this resource-intensive therapy on those patients likely to benefit. This study sought to create a selection model using machine learning (ML) tools for refractory cardiac arrest patients undergoing ECPR.

DESIGN

Retrospective cohort study.

SETTING

Cardiac ICU in a Quaternary Care Center.

PATIENTS

Adults 18-75 years old with refractory OHCA caused by a shockable rhythm.

METHODS

Three hundred seventy-six consecutive patients with refractory OHCA and a shockable presenting rhythm were analyzed, of which 301 underwent ECPR and cannulation for venoarterial extracorporeal membrane oxygenation. Clinical variables that were widely available at the time of cannulation were analyzed and ranked on their ability to predict neurologically favorable survival.

INTERVENTIONS

ML was used to train supervised models and predict favorable neurologic outcomes of ECPR. The best-performing models were internally validated using a holdout test set.

MEASUREMENTS AND MAIN RESULTS

Neurologically favorable survival occurred in 119 of 301 patients (40%) receiving ECPR. Rhythm at the time of cannulation, intermittent or sustained return of spontaneous circulation, arrest to extracorporeal membrane oxygenation perfusion time, and lactic acid levels were the most predictive of the 11 variables analyzed. All variables were integrated into a training model that yielded an in-sample area under the receiver-operating characteristic curve (AUC) of 0.89 and a misclassification rate of 0.19. Out-of-sample validation of the model yielded an AUC of 0.80 and a misclassification rate of 0.23, demonstrating acceptable prediction ability.

CONCLUSIONS

ML can develop a tiered risk model to guide ECPR patient selection with tailored arrest profiles.

Extracorporeal vs. conventional CPR for out-of-hospital cardiac arrest: A systematic review and meta-analysis

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) remains a significant cause of mortality and morbidity worldwide. Extracorporeal cardiopulmonary resuscitation (ECPR) is a potential intervention for OHCA, but its effectiveness compared to conventional cardiopulmonary resuscitation (CCPR) needs further evaluation.

METHOD

We systematically searched PubMed, Embase, the Cochrane Library, Web of Science, and ClinicalTrials.gov for relevant studies from January 2010 to March 2023. Pooled meta-analysis was performed to investigate any potential association between ECPR and improved survival and neurological outcomes.

RESULTS

This systematic review and meta-analysis included two randomized controlled trials enrolling 162 participants and 10 observational cohort studies enrolling 4507 participants. The pooled meta-analysis demonstrated that compared to CCRP, ECPR did not improve survival and neurological outcomes at 180 days following OHCA (RR: 3.39, 95% CI: 0.79 to 14.64; RR: 2.35, 95% CI: 0.97 to 5.67). While a beneficial effect of ECPR was obtained regarding 30-day survival and neurological outcomes. Furthermore, ECPR was associated with a higher risk of bleeding complications. Subgroup analysis showed that ECPR was prominently beneficial when exclusively initiated in the emergency department. Additional post-resuscitation treatments did not significantly impact the efficacy of ECPR on 180-day survival with favorable neurological outcomes.

CONCLUSIONS

There is no high-quality evidence supporting the superiority of ECPR over CCPR in terms of survival and neurological outcomes in OHCA patients. However, due to the potential for bias, heterogeneity among studies, and inconsistency in practice, the non-significant results do not preclude the potential benefits of ECPR. Further high-quality research is warranted to optimize ECPR practice and provide more generalizable evidence. Clinical trial registration PROSPERO, https://www.crd.york.ac.uk/prospero/, registry number: CRD42023402211.

[Open questions with respect to extracorporeal circulatory support 2024]

The use of extracorporeal circulatory support, both for cardiogenic shock and during resuscitation, still presents many unanswered questions. The inclusion and exclusion criteria for such a resource-intensive treatment must be clearly defined, considering that these criteria are directly associated with the type and location of treatment. For example, it is worth questioning the viability of an extracorporeal resuscitation program in areas where it is impossible to achieve low-flow times under 60 min due to local limitations. Additionally, the best approach for further treatment, including whether it is necessary to regularly relieve the left ventricle, must be explored. To find answers to some of these questions, large-scale, multicenter, randomized studies and registers must be performed. Until then this treatment must be carefully considered before use.

Evaluating the impact of ELSO guideline adherence on favorable neurological outcomes among patients requiring extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest

AIM

Selecting the appropriate candidates for extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) is challenging. Previously, the Extracorporeal Life Support Organization (ELSO) guidelines suggested the example of inclusion criteria. However, it is unclear whether patients who meet the inclusion criteria of the ELSO guidelines have more favorable outcomes. We aimed to evaluate the relationship between the outcomes and select inclusion criteria of the ELSO guidelines.

METHODS

We conducted a post-hoc analysis of a multicenter prospective study conducted between 2019 and 2021. Adult patients with OHCA treated with ECPR were included. The primary outcome was a favorable neurological outcome (Cerebral Performance Category of 1 or 2) at 30 days. An ELSO criteria score was assigned based on four criteria: (i) age < 70 years; (ii) witness; (iii) bystander CPR; and (iv) low-flow time (<60 min). Subgroup analysis based on initial cardiac rhythm was performed.

RESULTS

Among 9,909 patients, 227 with OHCA were included. The proportion of favorable neurological outcomes according to the number of ELSO criteria met were: 0.0% (0/3), 0 points; 0.0% (0/23), 1 point; 3.0% (2/67), 2 points; 7.3% (6/82), 3 points; and 16.3% (7/43), 4 points. A similar tendency was observed in patients with an initial shockable rhythm. However, no such relationship was observed in those with an initial non-shockable rhythm.

CONCLUSION

Patients who adhered more closely to specific inclusion criteria of the ELSO guidelines demonstrated a tendency towards a higher rate of favorable neurological outcomes. However, the relationship was heterogeneous according to initial rhythm.

Extracorporeal cardiopulmonary resuscitation for patients with refractory out-of-hospital cardiac arrest: a propensity score matching, observational study

Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly performed as an adjunct to conventional cardiopulmonary resuscitation (CCPR) for refractory out-of-hospital cardiac arrest (OHCA). However, the specific benefits of ECPR concerning survival with favorable neurological outcomes remain uncertain. This study aimed to investigate the potential advantages of ECPR in the management of refractory OHCA. We conducted a retrospective cohort study involved OHCA patients between January 2016 and May 2021. Patients were categorized into ECPR or CCPR groups. The primary endpoint assessed was survival with favorable neurological outcomes, and the secondary outcome was survival rate. Multivariate logistic regression analyses, with and without 1:2 propensity score matching, were employed to assess ECPR's effect. In total, 1193 patients were included: 85underwent ECPR, and 1108 received CCPR. Compared to the CCPR group, the ECPR group exhibited notably higher survival rate (29.4% vs. 2.4%; p < 0.001). The ECPR group also exhibited a higher proportion of survival with favorable neurological outcome than CCPR group (17.6% vs. 0.7%; p < 0.001). Multivariate logistic regression analysis demonstrated that ECPR correlated with increased odds of survival with favorable neurological outcome (adjusted odds ratio: 13.57; 95% confidence interval (CI) 4.60-40.06). Following propensity score matching, the ECPR group showed significantly elevated odds of survival with favorable neurological outcomes (adjusted odds ratio: 13.31; 95% CI 1.61-109.9). This study demonstrated that in comparison to CCPR, ECPR may provide survival benefit and increase the odds of favorable neurological outcomes in selected OHCA patients.

A national multi centre pre-hospital ECPR stepped wedge study; design and rationale of the ON-SCENE study

BACKGROUND

The likelihood of return of spontaneous circulation with conventional advanced life support is known to have an exponential decline and therefore neurological outcome after 20 min in patients with a cardiac arrest is poor. Initiation of venoarterial ExtraCorporeal Membrane Oxygenation (ECMO) during resuscitation might improve outcomes if used in time and in a selected patient category. However, previous studies have failed to significantly reduce the time from cardiac arrest to ECMO flow to less than 60 min. We hypothesize that the initiation of Extracorporeal Cardiopulmonary Resuscitation (ECPR) by a Helicopter Emergency Medical Services System (HEMS) will reduce the low flow time and improve outcomes in refractory Out of Hospital Cardiac Arrest (OHCA) patients.

METHODS

The ON-SCENE study will use a non-randomised stepped wedge design to implement ECPR in patients with witnessed OHCA between the ages of 18-50 years old, with an initial presentation of shockable rhythm or pulseless electrical activity with a high suspicion of pulmonary embolism, lasting more than 20, but less than 45 min. Patients will be treated by the ambulance crew and HEMS with prehospital ECPR capabilities and will be compared with treatment by ambulance crew and HEMS without prehospital ECPR capabilities. The primary outcome measure will be survival at hospital discharge. The secondary outcome measure will be good neurological outcome defined as a cerebral performance categories scale score of 1 or 2 at 6 and 12 months.

DISCUSSION

The ON-SCENE study focuses on initiating ECPR at the scene of OHCA using HEMS. The current in-hospital ECPR for OHCA obstacles encompassing low survival rates in refractory arrests, extended low-flow durations during transportation, and the critical time sensitivity of initiating ECPR, which could potentially be addressed through the implementation of the HEMS system. When successful, implementing on-scene ECPR could significantly enhance survival rates and minimize neurological impairment.

TRIAL REGISTRATION

Clinicaltyrials.gov under NCT04620070, registration date 3 November 2020.

What factors are effective on the CPR duration of patients under extracorporeal cardiopulmonary resuscitation: a single-center retrospective study

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is an alternative method for patients with reversible causes of cardiac arrest (CA) after conventional cardiopulmonary resuscitation (CCPR). However, cardiopulmonary resuscitation (CPR) duration during ECPR can vary due to multiple factors. Healthcare providers need to understand these factors to optimize the resuscitation process and improve outcomes. The aim of this study was to examine the different variables impacting the duration of CPR in patients undergoing ECPR.

METHODS

This retrospective, single-center, observational study was conducted on adult patients who underwent ECPR due to in-hospital CA (IHCA) or out-of-hospital CA (OHCA) at Hamad General Hospital (HGH), the tertiary governmental hospital of Qatar, between February 2016 and March 2020. Univariate and multivariate binary logistic regression analyses were performed to identify the prognostic factors associated with CPR duration, including demographic and clinical variables, as well as laboratory tests.

RESULTS

The mean ± standard division age of the 48 participants who underwent ECPR was 41.50 ± 13.15 years, and 75% being male. OHCA and IHCA were reported in 77.1% and 22.9% of the cases, respectively. The multivariate analysis revealed that several factors were significantly associated with an increased CPR duration: higher age (OR: 1.981, 95%CI: 1.021-3.364, P = 0.025), SOFA score (OR: 3.389, 95%CI: 1.289-4.911, P = 0.013), presence of comorbidities (OR: 3.715, 95%CI: 1.907-5.219, P = 0.026), OHCA (OR: 3.715, 95%CI: 1.907-5.219, P = 0.026), and prolonged collapse-to-CPR time (OR: 1.446, 95%CI:1.092-3.014, P = 0.001). Additionally, the study found that the initial shockable rhythm was inversely associated with the duration of CPR (OR: 0.271, 95%CI: 0.161-0.922, P = 0.045). However, no significant associations were found between laboratory tests and CPR duration.

CONCLUSION

These findings suggest that age, SOFA score, comorbidities, OHCA, collapse-to-CPR time, and initial shockable rhythm are important factors influencing the duration of CPR in patients undergoing ECPR. Understanding these factors can help healthcare providers better predict and manage CPR duration, potentially improving patient outcomes. Further research is warranted to validate these findings and explore additional factors that may impact CPR duration in this population.

Prognostic Significance of Signs of Life in Out-of-Hospital Cardiac Arrest Patients Undergoing Extracorporeal Cardiopulmonary Resuscitation

OBJECTIVES

Signs of life (SOLs) during cardiac arrest (gasping, pupillary light reaction, or any form of body movement) are suggested to be associated with favorable neurologic outcomes in out-of-hospital cardiac arrest (OHCA). While data has demonstrated that extracorporeal cardiopulmonary resuscitation (ECPR) can improve outcomes in cases of refractory cardiac arrest, it is expected that other contributing factors lead to positive outcomes. This study aimed to investigate whether SOL on arrival is associated with neurologic outcomes in patients with OHCA who have undergone ECPR.

DESIGN

Retrospective multicenter registry study.

SETTING

Thirty-six facilities participating in the Study of Advanced life support for Ventricular fibrillation with Extracorporeal circulation in Japan II (SAVE-J II).

PATIENTS

Consecutive patients older than 18 years old who were admitted to the Emergency Department with OHCA between January 1, 2013, and December 31, 2018, and received ECPR.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were classified into two groups according to the presence or absence of SOL on arrival. The primary outcome was a favorable neurologic outcome (Cerebral Performance Category 1 or 2) at discharge. Of the 2157 patients registered in the SAVE-J II database, 1395 met the inclusion criteria, and 250 (17.9%) had SOL upon arrival. Patients with SOL had more favorable neurologic outcomes than those without SOL (38.0% vs. 8.1%; p < 0.001). Multivariate analysis showed that SOL on arrival was independently associated with favorable neurologic outcomes (odds ratio, 5.65 [95% CI, 3.97-8.03]; p < 0.001).

CONCLUSIONS

SOL on arrival was associated with favorable neurologic outcomes in patients with OHCA undergoing ECPR. In patients considered for ECPR, the presence of SOL on arrival can assist the decision to perform ECPR.

Extracorporeal cardiopulmonary resuscitation for refractory cardiac arrest: an overview of current practice and evidence

Cardiac arrest (CA) is a common and potentially avoidable cause of death, while constituting a substantial public health burden. Although survival rates for out-of-hospital cardiac arrest (OHCA) have improved in recent decades, the prognosis for refractory OHCA remains poor. The use of veno-arterial extracorporeal membrane oxygenation during cardiopulmonary resuscitation (ECPR) is increasingly being considered to support rescue measures when conventional cardiopulmonary resuscitation (CPR) fails. ECPR enables immediate haemodynamic and respiratory stabilisation of patients with CA who are refractory to conventional CPR and thereby reduces the low-flow time, promoting favourable neurological outcomes. In the case of refractory OHCA, multiple studies have shown beneficial effects in specific patient categories. However, ECPR might be more effective if it is implemented in the pre-hospital setting to reduce the low-flow time, thereby limiting permanent brain damage. The ongoing ON-SCENE trial might provide a definitive answer regarding the effectiveness of ECPR. The aim of this narrative review is to present the most recent literature available on ECPR and its current developments.

Prognostic value of arterial carbon dioxide tension during cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients receiving extracorporeal resuscitation

BACKGROUND

Current guidelines on extracorporeal cardiopulmonary resuscitation (ECPR) recommend careful patient selection, but precise criteria are lacking. Arterial carbon dioxide tension (PaCO2) has prognostic value in out-of-hospital cardiac arrest (OHCA) patients but has been less studied in patients receiving ECPR. We studied the relationship between PaCO2 during cardiopulmonary resuscitation (CPR) and neurological outcomes of OHCA patients receiving ECPR and tested whether PaCO2 could help ECPR selection.

METHODS

This single-centre retrospective study enrolled 152 OHCA patients who received ECPR between January 2012 and December 2020. Favorable neurological outcome (FO) at discharge was the primary outcome. We used multivariable logistic regression to determine the independent variables for FO and generalised additive model (GAM) to determine the relationship between PaCO2 and FO. Subgroup analyses were performed to test discriminative ability of PaCO2 in subgroups of OHCA patients.

RESULTS

Multivariable logistic regression showed that PaCO2 was independently associated with FO after adjusting for other favorable resuscitation characteristics (Odds ratio [OR] 0.23, 95% Confidence Interval [CI] 0.08-0.66, p-value = 0.006). GAM showed a near-linear reverse relationship between PaCO2 and FO. PaCO2 < 70 mmHg was the cutoff point for predicting FO. PaCO2 also had prognostic value in patients with less favorable characteristics, including non-shockable rhythm (OR, 3.78) or low flow time > 60 min (OR, 4.66).

CONCLUSION

PaCO2 before ECMO implementation had prognostic value for neurological outcomes in OHCA patients. Patients with PaCO2 < 70 mmHg had higher possibility of FO, even in those with non-shockable rhythm or longer low-flow duration. PaCO2 could serve as an ECPR selection criterion.

Prognostic effects of cardiopulmonary resuscitation (CPR) start time and the interval between CPR to extracorporeal cardiopulmonary resuscitation (ECPR) on patient outcomes under extracorporeal membrane oxygenation (ECMO): a single-center, retrospective observational study

BACKGROUND

The impact of the chronological sequence of events, including cardiac arrest (CA), initial cardiopulmonary resuscitation (CPR), return of spontaneous circulation (ROSC), and extracorporeal cardiopulmonary resuscitation (ECPR) implementation, on clinical outcomes in patients with both out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA), is still not clear. The aim of this study was to investigate the prognostic effects of the time interval from collapse to start of CPR (no-flow time, NFT) and the time interval from start of CPR to implementation of ECPR (low-flow time, LFT) on patient outcomes under Extracorporeal Membrane Oxygenation (ECMO).

METHODS

This single-center, retrospective observational study was conducted on 48 patients with OHCA or IHCA who underwent ECMO at Hamad General Hospital (HGH), the tertiary governmental hospital of Qatar, between February 2016 and March 2020. We investigated the impact of prognostic factors such as NFT and LFT on various clinical outcomes following cardiac arrest, including 24-hour survival, 28-day survival, CPR duration, ECMO length of stay (LOS), ICU LOS, hospital LOS, disability (assessed using the modified Rankin Scale, mRS), and neurological status (evaluated based on the Cerebral Performance Category, CPC) at 28 days after the CA.

RESULTS

The results of the adjusted logistic regression analysis showed that a longer NFT was associated with unfavorable clinical outcomes. These outcomes included longer CPR duration (OR: 1.779, 95%CI: 1.218-2.605, P = 0.034) and decreased survival rates for ECMO at 24 h (OR: 0.561, 95%CI: 0.183-0.903, P = 0.009) and 28 days (OR: 0.498, 95%CI: 0.106-0.802, P = 0.011). Additionally, a longer LFT was found to be associated only with a higher probability of prolonged CPR (OR: 1.818, 95%CI: 1.332-3.312, P = 0.006). However, there was no statistically significant connection between either the NFT or the LFT and the improvement of disability or neurologically favorable survival after 28 days of cardiac arrest.

CONCLUSIONS

Based on our findings, it has been determined that the NFT is a more effective predictor than the LFT in assessing clinical outcomes for patients with OHCA or IHCA who underwent ECMO. This understanding of their distinct predictive abilities enables medical professionals to identify high-risk patients more accurately and customize their interventions accordingly.

Factors associated with favourable neurological outcomes following cardiopulmonary resuscitation for out-of-hospital cardiac arrest: A retrospective multi-centre cohort study

Aim

To investigate the factors associated with favourable neurological outcomes in adult patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA).

Methods

This retrospective observational study used secondary analysis of the SAVE-J II multicentre registry data from 36 institutions in Japan. Between 2013 and 2018, 2157 patients with OHCA who underwent ECPR were enrolled in SAVE-J II. A total of 1823 patients met the study inclusion criteria. Adult patients (aged ≥ 18 years) with OHCA, who underwent ECPR before admission to the intensive care unit, were included in our secondary analysis. The primary outcome was a favourable neurological outcome at hospital discharge, defined as a Cerebral Performance Category score of 1 or 2. We used a multivariate logistic regression model to examine the association between factors measured at the incident scene or upon hospital arrival and favourable neurological outcomes.

Results

Multivariable analysis revealed that shockable rhythm at the scene [odds ratio (OR); 2.11; 95% confidence interval (CI), 1.16-3.95] and upon hospital arrival (OR 2.59; 95% CI 1.60-4.30), bystander CPR (OR 1.63; 95% CI 1.03-1.88), body movement during resuscitation (OR 7.10; 95% CI 1.79-32.90), gasping (OR 4.33; 95% CI 2.57-7.28), pupillary reflex on arrival (OR 2.93; 95% CI 1.73-4.95), and male sex (OR 0.43; 95% CI 0.24-0.75) significantly correlated with neurological outcomes.

Conclusions

Shockable rhythm, bystander CPR, body movement during resuscitation, gasping, pupillary reflex, and sex were associated with favourable neurological outcomes in patients with OHCA treated with ECPR.

Post-Cardiac Arrest Care in Adult Patients After Extracorporeal Cardiopulmonary Resuscitation

OBJECTIVES

Extracorporeal cardiopulmonary resuscitation (ECPR) serves as a lifesaving intervention for patients experiencing refractory cardiac arrest. With its expanding usage, there is a burgeoning focus on improving patient outcomes through optimal management in the acute phase after cannulation. This review explores systematic post-cardiac arrest management strategies, associated complications, and prognostication in ECPR patients.

DATA SOURCES

A PubMed search from inception to 2023 using search terms such as post-cardiac arrest care, ICU management, prognostication, and outcomes in adult ECPR patients was conducted.

STUDY SELECTION

Selection includes original research, review articles, and guidelines.

DATA EXTRACTION

Information from relevant publications was reviewed, consolidated, and formulated into a narrative review.

DATA SYNTHESIS

We found limited data and no established clinical guidelines for post-cardiac arrest care after ECPR. In contrast to non-ECPR patients where systematic post-cardiac arrest care is shown to improve the outcomes, there is no high-quality data on this topic after ECPR. This review outlines a systematic approach, albeit limited, for ECPR care, focusing on airway/breathing and circulation as well as critical aspects of ICU care, including analgesia/sedation, mechanical ventilation, early oxygen/C o2 , and temperature goals, nutrition, fluid, imaging, and neuromonitoring strategy. We summarize common on-extracorporeal membrane oxygenation complications and the complex nature of prognostication and withdrawal of life-sustaining therapy in ECPR. Given conflicting outcomes in ECPR randomized controlled trials focused on pre-cannulation care, a better understanding of hemodynamic, neurologic, and metabolic abnormalities and early management goals may be necessary to improve their outcomes.

CONCLUSIONS

Effective post-cardiac arrest care during the acute phase of ECPR is paramount in optimizing patient outcomes. However, a dearth of evidence to guide specific management strategies remains, indicating the necessity for future research in this field.

Extracorporeal cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest: 10-year experience in a metropolitan cardiac arrest centre in Milan, Italy

Introduction

Growing evidence supports extracorporeal cardiopulmonary resuscitation (ECPR) for refractory out-of-hospital cardiac arrest (OHCA) patients, especially in experienced centres. We present characteristics, treatments, and outcomes of patients treated with ECPR in a high-volume cardiac arrest centre in the metropolitan area of Milan, Italy and determine prognostic factors.

Methods

Refractory OHCA patients treated with ECPR between 2013 and 2022 at IRCCS San Raffaele Scientific Institute in Milan had survival and neurological outcome assessed at hospital discharge.

Results

Out of 307 consecutive OHCA patients treated with ECPR (95% witnessed, 66% shockable, low-flow 70 [IQR 58-81] minutes), 17% survived and 9.4% had favourable neurological outcome. Survival and favourable neurological outcome increased to 51% (OR = 8.7; 95% CI, 4.3-18) and 28% (OR = 6.3; 95% CI, 2.8-14) when initial rhythm was shockable and low-flow (time between CPR initiation and ROSC or ECMO flow) ≤60 minutes and decreased to 9.5% and 6.3% when low-flow exceeded 60 minutes (72% of patients). At multivariable analysis, shockable rhythm (aOR for survival = 2.39; 95% CI, 1.04-5.48), shorter low-flow (aOR = 0.95; 95% CI, 0.94-0.97), intermittent ROSC (aOR = 2.5; 95% CI, 1.2-5.6), and signs of life (aOR = 3.7; 95% CI, 1.5-8.7) were associated with better outcomes. Survival reached 10% after treating 104 patients (p for trend <0.001).

Conclusions

Patients with initial shockable rhythm, intermittent ROSC, signs of life, and low-flow ≤60 minutes had higher success of ECPR for refractory OHCA. Favourable outcomes were possible beyond 60 minutes of low-flow, especially with concomitant favourable prognostic factors. Outcomes improved as the case-volume increased, supporting treatment in high-volume cardiac arrest centres.

Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) and ultrasound-guided left stellate ganglion block to rescue out of hospital cardiac arrest due to refractory ventricular fibrillation: A case report

Out of hospital cardiac arrest from shockable rhythms that is refractory to standard treatment is a unique challenge. Such patients can achieve neurological recovery even with long low-flow times if perfusion can somehow be restored to the heart and brain. Extracorporeal cardiopulmonary resuscitation is an effective treatment for refractory cardiac arrest if applied early and accurately, but often cannot be directly implemented by frontline providers and has strict inclusion/exclusion criteria. We present the case of a novel treatment strategy for out of hospital cardiac arrest due to refractory ventricular fibrillation utilizing Resuscitative Endovascular Balloon Occlusion of the Aorta-assisted cardiopulmonary resuscitation and intra-arrest left stellate ganglion blockade to achieve return of spontaneous circulation and eventual good neurological outcome after 101 minutes of downtime.

Recovery and Survival of Patients After Out-of-Hospital Cardiac Arrest: A Literature Review Showcasing the Big Picture of Intensive Care Unit-Related Factors

As an important public health issue, out-of-hospital cardiac arrest (OHCA) requires several stages of high quality medical care, both on-field and after hospital admission. Post-cardiac arrest shock can lead to severe neurological injury, resulting in poor recovery outcome and increased risk of death. These characteristics make this condition one of the most important issues to deal with in post-OHCA patients hospitalized in intensive care units (ICUs). Also, the majority of initial post-resuscitation survivors have underlying coronary diseases making revascularization procedure another crucial step in early management of these patients. Besides keeping myocardial blood flow at a satisfactory level, other tissues must not be neglected as well, and maintaining mean arterial pressure within optimal range is also preferable. All these procedures can be simplified to a certain level along with using targeted temperature management methods in order to decrease metabolic demands in ICU-hospitalized post-OHCA patients. Additionally, withdrawal of life-sustaining therapy as a controversial ethical topic is under constant re-evaluation due to its possible influence on overall mortality rates in patients initially surviving OHCA. Focusing on all of these important points in process of managing ICU patients is an imperative towards better survival and complete recovery rates.

Improved Extracorporeal Cardiopulmonary Resuscitation (ECPR) Outcomes Is Associated with a Restrictive Patient Selection Algorithm

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is a leading cause of mortality. Despite decades of intensive research and several technological advancements, survival rates remain low. The integration of extracorporeal cardiopulmonary resuscitation (ECPR) has been recognized as a promising approach in refractory OHCA. However, evidence from recent randomized controlled trials yielded contradictory results, and the criteria for selecting eligible patients are still a subject of debate.

METHODS

This study is a retrospective analysis of refractory OHCA patients treated with ECPR. All adult patients who received ECPR, according to the hospital algorithm, from 2013 to 2021 were included. Two different algorithms were used during this period. A "permissive" algorithm was used from 2013 to mid-2016. Subsequently, a revised algorithm, more "restrictive", based on international guidelines, was implemented from mid-2016 to 2021. Key differences between the two algorithms included reducing the no-flow time from less than three minutes to zero minutes (implying that the cardiac arrests must occur in the presence of a witness with immediate CPR initiation), reducing low-flow duration from 100 to 60 min, and lowering the age limit from 65 to 55 years. The aim of this study is to compare these two algorithms (permissive (1) and restrictive (2)) to determine if the use of a restrictive algorithm was associated with higher survival rates.

RESULTS

A total of 48 patients were included in this study, with 23 treated under Algorithm 1 and 25 under Algorithm 2. A significant difference in survival rate was observed in favor of the restrictive algorithm (9% vs. 68%, p < 0.05). Moreover, significant differences emerged between algorithms regarding the no-flow time (0 (0-5) vs. 0 (0-0) minutes, p < 0.05). Survivors had a significantly shorter no-flow and low-flow time (0 (0-0) vs. 0 (0-3) minutes, p < 0.01 and 40 (31-53) vs. 60 (45-80) minutes, p < 0.05), respectively.

CONCLUSION

The present study emphasizes that a stricter selection of OHCA patients improves survival rates in ECPR.

Prognostic influence of mechanical cardiopulmonary resuscitation on survival in patients with out-of-hospital cardiac arrest undergoing ECPR on VA-ECMO

Introduction

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in extracorporeal cardiopulmonary resuscitation (ECPR) in selected patients after out-of-hospital cardiac arrest (OHCA) is an established method if return of spontaneous circulation cannot be achieved. Automated chest compression devices (ACCD) facilitate transportation of patients under ongoing CPR and might improve outcome. We thus sought to evaluate prognostic influence of mechanical CPR using ACCD in patients presenting with OHCA treated with ECPR including VA-ECMO.

Methods

We retrospectively analyzed data of 171 consecutive patients treated for OHCA using ECPR in our cardiac arrest center from the years 2016 to 2022. A Cox proportional hazards model was used to identify characteristics related with survival.

Results

Of the 171 analyzed patients (84% male, mean age 56 years), 12% survived the initial hospitalization with favorable neurological outcome. The primary reason for OHCA was an acute coronary event (72%) followed by primary arrhythmia (9%) and non-ischemic cardiogenic shock (6.7%). In most cases, the collapse was witnessed (83%) and bystander CPR was performed (83%). The median time from collapse to VA-ECMO was 81 min (Q1: 69 min, Q3: 98 min). No survival benefit was seen for patients resuscitated using ACCD. Patients in whom an ACCD was used presented with overall longer times from collapse to ECMO than those who were resuscitated manually [83 min (Q1: 70 min, Q3: 98 min) vs. 69 min (Q1: 57 min, Q3: 84 min), p = 0.004].

Conclusion

No overall survival benefit of the use of ACCD before ECPR is established was found, possibly due to longer overall CPR duration. This may arguably be because of the limited availability of ACCD in pre-clinical paramedic service at the time of observation. Increasing the availability of these devices might thus improve treatment of OHCA, presumably by providing efficient CPR during transportation and transfer.

Impact of clinical variables on outcomes in refractory cardiac arrest patients undergoing extracorporeal cardiopulmonary resuscitation

Background

In the past two decades, extracorporeal resuscitation (ECPR) has been increasingly used in the management of refractory cardiac arrest (CA) patients. Decision algorithms have been used to guide the care such patients, but the effectiveness of such decision-making tools is not well described. The aim of this study was to compare the rate of survival with a good neurologic outcome of patients treated with ECPR meeting all criteria of a clinical decision-making tool for the initiation of ECPR to those for whom ECPR was implemented outside of the algorithm.

Methods

All patients who underwent E-CPR between January 2014 and December 2021 at the Montreal Heart Institute were included in this retrospective analysis. We dichotomized the cohort according to adherence or non-adherence with the ECPR decision-making tool, which included the following criteria: age ≤65 years, initial shockable rhythm, no-flow time <5 min, serum lactate <13 mmol/L. Patients were included in the "IN" group when they met all criteria of the decision-making tool and in the "OUT" group when at least one criterion was not met.

Main outcomes and measures

The primary outcome was survival with intact neurological status at 30 days, defined by a Cerebral Performance Category (CPC) Scale 1 and 2.

Results

A total of 41 patients (IN group, n = 11; OUT group, n = 30) were included. A total of 4 (36%) patients met the primary outcome in the IN group and 7 (23%) in the OUT group [odds ratio (OR): 1.88 (95% CI, 0.42-8.34); P = 0.45]. However, survival with a favorable outcome decreased steadily with 2 or more deviations from the decision-making tool [2 deviations: 1 (11%); 3 deviations: 0 (0%)].

Conclusion and relevance

Most patients supported with ECPR fell outside of the criteria encompassed in a clinical decision-making tool, which highlights the challenge of optimal selection of ECPR candidates. Survival rate with a good neurologic outcome did not differ between the IN and OUT groups. However, survival with favorable outcome decreased steadily after one deviation from the decision-making tool. More studies are needed to help select proper candidates with refractory CA patients for ECPR.

Low-flow time and outcomes in out-of-hospital cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation

INTRODUCTION

In out-of-hospital cardiac arrest (OHCA) patients with extracorporeal cardiopulmonary resuscitation (ECPR), the association between low-flow time, the duration between the initiation of conventional cardiopulmonary resuscitation and the establishment of ECPR, and outcomes has not been clearly determined.

METHODS

This was a secondary analysis of the retrospective multicenter registry in Japan. This study registered patients ≥18 years old who were admitted to the emergency department for OHCA and underwent ECPR between January, 2013 and December, 2018. Low-flow time was defined as the time from initiation of conventional cardiopulmonary resuscitation to the establishment of ECPR, and patients were categorized into two groups according to the visualized association of the restricted cubic spline curve. The primary outcome was survival discharge. Cubic spline analyses and multivariable logistic regression analyses were performed to assess the nonlinear associations between low-flow time and outcomes.

RESULTS

A total of 1,524 patients were included. The median age was 60 years, and the median low-flow time was 52 (42-53) mins. The overall survival at hospital discharge and favorable neurological outcomes were 27.8% and 14.2%, respectively. The cubic spline analysis showed a decreased trend of survival discharge rates and favorable neurological outcomes with shorter low-flow time between 20 and 60 mins, with little change between the following 60 and 80 mins. The multivariable logistic regression analyses showed that patients with long low-flow time (>40 mins) compared to those with short low-flow time (0-40 mins) had significantly worse survival (adjusted odds ratio 0.42; 95% confidence intervals, 0.31-0.57) and neurological outcomes (0.65; 0.45-0.95, respectively).

CONCLUSIONS

The survival discharge and neurological outcomes of patients with low-flow time shorter than 40 min are better than those of patients with longer low-flow time.

Association between neuromuscular blocking agent use and outcomes among out-of-hospital cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation and target temperature management: A secondary analysis of the SAVE-J II study

Background

Neuromuscular blocking agents are used to control shivering in cardiac arrest patients treated with target temperature management. However, their effect on outcomes in patients treated with extracorporeal cardiopulmonary resuscitation is unclear.

Methods

This study was a secondary analysis of the SAVE-J II study, a retrospective multicenter study of 2175 out-of-hospital cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation in Japan. We classified patients into those who received neuromuscular blocking agents and those who did not and compared in-hospital mortality and incidence rates of favorable neurological outcome and in-hospital pneumonia between the groups using multivariable regression models and stabilized inverse probability weighting with propensity scores.

Results

Six hundred sixty patients from the SAVE-J II registry were analyzed. Neuromuscular blocking agents were used in 451 patients (68.3%). After adjusting for potential confounders, neuromuscular blocking agents use was not significantly associated with in-hospital mortality (aHR 0.88; 95% CI, 0.67-1.14), favorable neurological outcome (aOR 0.85; 95% CI, 0.60-1.11), or pneumonia (aOR 1.52; 95% CI, 0.85-2.71). The results for in-hospital mortality (aHR 0.89; 95% CI, 0.64-1.25), favorable neurological outcome (aOR 0.94; 95% CI, 0.59-1.48) and pneumonia (aOR 1.59; 95% CI, 0.74-3.41) were similar after weighting was performed.

Conclusions

Although data on the rationale for using neuromuscular blocking agents were unavailable, their use was not significantly associated with outcomes in out-of-hospital cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation and targeted temperature management. Neuromuscular blocking agents should be used based on individual clinical indications.

First documented rhythm and clinical outcome in children who undergo extracorporeal cardiopulmonary resuscitation for in-hospital cardiac arrest: A report from the american heart association get with the guidelines® - resuscitation registry (GWTG-R)

INTRODUCTION

Outcomes of conventional cardiopulmonary resuscitation are improved when the initial rhythm is shockable (ventricular fibrillation or pulseless ventricular tachycardia). In children, the first documented rhythm is typically asystole or pulseless electrical activity. We evaluate the role the initial rhythm plays in outcomes for children undergoing extracorporeal cardiopulmonary resuscitation (ECPR) for in-hospital cardiac arrest.

METHODS

Consecutive patients < 18 years with in-hospital ECPR events ≥ 10 minutes reported to the American Heart Association Get With The Guidelines® - Resuscitation registry from 2014 to 2019 were included. Primary outcome was survival to hospital discharge. Logistic regression modeling was used to compute propensity score matching based on patient, cardiac arrest event and hospital characteristics; patients with initial shockable rhythm were matched to patients with initial non-shockable rhythm.

RESULTS

The final cohort included 466 patients, of which 82 (18%) had a shockable, and 384 (82%) had a non-shockable initial rhythm. After propensity score matching of 287 (62%) patients, there was no difference in survival to hospital discharge (risk ratio [RR] 1.2, 95% CI, 0.95-1.53, p = 0.13) or favorable neurologic outcome, defined as Pediatric Cerebral Performance Category (PCPC) of 1 or 2, or no decline from baseline (RR 1.28, 95% CI, 0.84-1.96, p = 0.25) between patients with and without shockable initial rhythm.

CONCLUSIONS

In children with in-hospital cardiac arrest undergoing ECPR, there was no significant difference in survival or favorable neurologic outcome between those with initial shockable rhythm compared to non-shockable rhythm. Further investigation to evaluate ECPR patient characteristics and outcomes is warranted to help guide eligibility and ECMO deployment practices.

Neurologic outcome and location of cardiac arrest in out-of-hospital cardiac arrest patients who underwent extracorporeal cardiopulmonary resuscitation: A multicentre retrospective cohort in Japan

Aim

We examined the association between the location of cardiac arrest and outcomes of patients with out-of-hospital cardiac arrest (OHCA) who underwent extracorporeal cardiopulmonary resuscitation (ECPR).

Methods

This was a secondary analysis of SAVE-J II, a multicentre retrospective registry with 36 participating institutions across Japan, which enrolled adult patients with OHCA who underwent ECPR. The outcomes of interest were favourable neurologic outcome at discharge. We compared the outcome between OHCA cases that occurred at residential and public locations, using a multilevel logistic regression model allowing for the random effect of each hospital.

Results

Among 1,744 enrolled OHCAs, 809 and 935 occurred at residential (house: 603; apartment: 206) and public (street: 260; workplace: 210; others: 465) locations, respectively. The proportion of favourable neurologic outcomes was lower in OHCAs at residential locations than those at public locations (88/781 (11.3%) vs.131/891 (14.7%); adjusted odds ratio, 0.72 [95% confidence interval, 0.53-0.99]). However, subgroup analyses for patients with EMS aged <65 years call to hospital arrival within 30 minutes or during daytime revealed less difference between residential and public locations.

Conclusion

When cardiac arrests occurred at residential locations, lower proportions of favourable neurologic outcomes were exhibited among patients with OHCA who underwent ECPR. However, the event's location may not affect the prognosis among appropriate and select cases when transported within a limited timeframe.

The Role of Extracorporeal Membrane Oxygenation ECMO in Accidental Hypothermia and Rewarming in Out-of-Hospital Cardiac Arrest Patients-A Literature Review

Accidental hypothermia, defined as an unintentional drop of the body core temperature below 35 °C, is one of the causes of cardiocirculatory instability and reversible cardiac arrest. Currently, extracorporeal life support (ECLS) rewarming is recommended as a first-line treatment for hypothermic cardiac arrest patients. The aim of the ECLS rewarming is not only rapid normalization of core temperature but also maintenance of adequate organ perfusion. Veno-arterial extracorporeal membrane oxygenation (ECMO) is a preferred technique due to its lower anticoagulation requirements and potential to prolong circulatory support. Although highly efficient, ECMO is acknowledged as an invasive treatment option, requiring experienced medical personnel and is associated with the risk of serious complications. In this review, we aimed to discuss the clinical aspects of ECMO management in severely hypothermic cardiac arrest patients.

Extracorporeal cardiopulmonary resuscitation versus conventional cardiopulmonary resuscitation in adults with cardiac arrest: a comparative meta-analysis and trial sequential analysis

BACKGROUND

Although outcomes of patients after cardiac arrest remain poor, studies have suggested that extracorporeal cardiopulmonary resuscitation (ECPR) might improve survival and neurological outcomes. We aimed to investigate any potential benefits of using ECPR over conventional cardiopulmonary resuscitation (CCPR) in patients with out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA).

METHODS

In this systematic review and meta-analysis, we searched MEDLINE via PubMed, Embase, and Scopus from Jan 1, 2000, to April 1, 2023, for randomised controlled trials and propensity-score matched studies. We included studies comparing ECPR with CCPR in adults (aged ≥18 years) with OHCA and IHCA. We extracted data from published reports using a prespecified data extraction form. We did random-effects (Mantel-Haenszel) meta-analyses and rated the certainty of evidence using the Grading of Recommendations, Assessments, Developments, and Evaluations (GRADE) approach. We rated the risk of bias of randomised controlled trials using the Cochrane risk-of-bias 2.0 tool, and that of observational studies using the Newcastle-Ottawa Scale. The primary outcome was in-hospital mortality. Secondary outcomes included complications during extracorporeal membrane oxygenation, short-term (from hospital discharge to 30 days after cardiac arrest) and long-term (≥90 days after cardiac arrest) survival with favourable neurological outcomes (defined as cerebral performance category scores 1 or 2), and survival at 30 days, 3 months, 6 months, and 1 year after cardiac arrest. We also did trial sequential analyses to evaluate the required information sizes in the meta-analyses to detect clinically relevant reductions in mortality.

FINDINGS

We included 11 studies (4595 patients receiving ECPR and 4597 patients receiving CCPR) in the meta-analysis. ECPR was associated with a significant reduction in overall in-hospital mortality (OR 0·67, 95% CI 0·51-0·87; p=0·0034; high certainty), without evidence of publication bias (pegger=0·19); the trial sequential analysis was concordant with the meta-analysis. When considering IHCA only, in-hospital mortality was lower in patients receiving ECPR than in those receiving CCPR (0·42, 0·25-0·70; p=0·0009), whereas when considering OHCA only, no differences were found (0·76, 0·54-1·07; p=0·12). Centre volume (ie, the number of ECPR runs done per year in each centre) was associated with reductions in odds of mortality (regression coefficient per doubling of centre volume -0·17, 95% CI -0·32 to -0·017; p=0·030). ECPR was also associated with an increased rate of short-term (OR 1·65, 95% CI 1·02-2·68; p=0·042; moderate certainty) and long-term (2·04, 1·41-2·94; p=0·0001; high certainty) survival with favourable neurological outcomes. Additionally, patients receiving ECPR had increased survival at 30-day (OR 1·45, 95% CI 1·08-1·96; p=0·015), 3-month (3·98, 1·12-14·16; p=0·033), 6-month (1·87, 1·36-2·57; p=0·0001), and 1-year (1·72, 1·52-1·95; p<0·0001) follow-ups.

INTERPRETATION

Compared with CCPR, ECPR reduced in-hospital mortality and improved long-term neurological outcomes and post-arrest survival, particularly in patients with IHCA. These findings suggest that ECPR could be considered for eligible patients with IHCA, although further research into patients with OHCA is warranted.

FUNDING

None.

Benefits, key protocol components, and considerations for successful implementation of extracorporeal cardiopulmonary resuscitation: a review of the recent literature

The application of venoarterial extracorporeal membrane oxygenation (ECMO) in patients unresponsive to conventional cardiopulmonary resuscitation (CPR) has significantly increased in recent years. To date, three published randomized trials have investigated the use of extracorporeal CPR (ECPR) in adults with refractory out-of-hospital cardiac arrest. Although these trials reported inconsistent results, they suggest that ECPR may have a significant survival benefit over conventional CPR in selected patients only when performed with strict protocol adherence in experienced emergency medical services-hospital systems. Several studies suggest that identifying suitable ECPR candidates and reducing the time from cardiac arrest to ECMO initiation are key to successful outcomes. Prehospital ECPR or the rendezvous approach may allow more patients to receive ECPR within acceptable timeframes than ECPR initiation on arrival at a capable hospital. ECPR is only one part of the system of care for resuscitation of cardiac arrest victims. Optimizing the chain of survival is critical to improving outcomes of patients receiving ECPR. Further studies are needed to find the optimal strategy for the use of ECPR.

ECPR Survivor Estimates: A Simulation-Based Approach to Comparing ECPR Delivery Strategies

Objective: The number of out-of-hospital cardiac arrest (OHCA) patients who may benefit from prehospital extracorporeal cardiopulmonary resuscitation (ECPR) is yet to be elucidated. Patient eligibility is determined both by case characteristics and physical proximity to an ECPR service. We applied accessibility principles to historical cardiac arrest data, to identify the number of patients who would have been eligible for prehospital ECPR in Sydney, Australia, and the potential survival benefit had prehospital ECPR been available.Methods: The New South Wales cardiac arrest registry between January 2017 to June 2021 included 39,387 cardiac arrests. We retrospectively defined two groups: 1) possible ECPR eligible arrests that would have triggered activation of a team, and 2) ECPR eligible arrests, those arrests that met ECPR inclusion criteria and remained refractory. Transport accessibility modeling was used to ascertain the number of arrests that would have been served by a hypothetical prehospital service and the potential survival benefit.Results: There were 699 arrests screened as possibly ECPR eligible in the Sydney metropolitan area, 488 of whom were subsequently confirmed as ECPR eligible refractory OHCA. Of these, 38% (n = 185) received intra-arrest transfer to hospital, with 37% (n = 180) arriving within 60 min. Using spatial and transport modeling, a prehospital team located at an optimal location could establish 437 (90%) patients onto ECMO within 60 min, with an estimated survival of 48% (IQR 38-57). Based on existing survival curves, compared to conventional CPR, an optimally located prehospital ECPR service has the potential to save one additional life for every 3.0 patients.Conclusions: A significant number of historical OHCA patients could have benefited from prehospital ECPR, with a potential survival benefit above conventional CPR.

Long-term survival, functional capacity and quality of life after refractory out-of-hospital cardiac arrest treated with mechanical circulatory support

Introduction

Studies on long-term outcomes after refractory out-of-hospital cardiac arrest (OHCA) treated with mechanical circulatory support (MCS) are limited. This study aimed to evaluate long-term neurologically intact survival, functional capacity and quality of life after refractory OHCA treated with MCS.

Methods

This was a follow-up study of survivors after refractory OHCA treated with MCS. Follow-up examinations comprised clinical assessment with transthoracic echocardiography and cardiopulmonary exercise test (CPX). Neurological and cognitive screening was evaluated with the Cerebral Performance Category (CPC) and Montreal Cognitive Assessment (MoCA test). A good neurological outcome was defined as CPC 1 or CPC 2. Health-related quality of life was measured by questionnaires (Short Form-36 (SF-36)).

Results

A total of 101 patients with refractory OHCA were treated with MCS at Aarhus University Hospital between 2015 and 2019. The total low-flow time was median 105 min [IQR, 94-123] minutes. The hospital discharge rate was 27%. At a mean follow-up time of 4.8 years ± 1.6 (range 2.8-6.1 years), 21 patients remained alive of whom 15 consented to participate in the present study. Good neurological outcome with CPC 1-2 was found in 93% (14/15) patients. No severe cognitive function was discovered; mean MoCA score of 26.4 ± 3.1. Functional capacity examined by CPX showed acceptable VO2 max values (23.9 ± 6.3 mL/kg/min). Mean SF-36 scores revealed an overall high level of quality of life in long-term survivors.

Conclusions

Long-term survival with a good neurological outcome with functional recovery was high in patients with refractory OHCA treated with MCS. These patients may expect a reasonable quality of life after discharge despite prolonged resuscitation.

Potential role for extracorporeal membrane oxygenation cardiopulmonary resuscitation (E-CPR) during in-hospital cardiac arrest in Australia: A nested cohort study

Objective

This study aims to evaluate the characteristics and outcomes of patients who fulfilled extracorporeal membrane oxygenation cardiopulmonary resuscitation (E-CPR) selection criteria during in-hospital cardiac arrest (IHCA).

Design

This is a nested cohort study.

Setting

Code blue data were collected across seven hospitals in Australia between July 2017 and August 2018.

Participants

Participants who fulfilled E-CPR selection criteria during IHCA were included.

Main outcome measures

Return of spontaneous circulation and survival and functional outcome at hospital discharge. Functional outcome was measured using the modified Rankin scale, with scores dichotomised into good and poor functional outcome.

Results

Twenty-three (23/144; 16%) patients fulfilled E-CPR selection criteria during IHCA, and 11/23 (47.8%) had a poor outcome. Patients with a poor outcome were more likely to have a non-shockable rhythm (81.8% vs. 16.7%; p = 0.002), and a longer duration of CPR (median 12.5 [5.5, 39.5] vs. 1.5 [0.3, 2.5] minutes; p < 0.001) compared to those with a good outcome. The majority of patients (18/19 [94.7%]) achieved sustained return of spontaneous circulation within 15 minutes of CPR. All five patients who had CPR >15 minutes had a poor outcome.

Conclusion

Approximately one in six IHCA patients fulfilled E-CPR selection criteria during IHCA, half of whom had a poor outcome. Non-shockable rhythm and longer duration of CPR were associated with poor outcome. Patients who had CPR for >15 minutes and a poor outcome may have benefited from E-CPR. The feasibility, effectiveness and risks of commencing E-CPR earlier in IHCA and among those with non-shockable rhythms requires further investigation.

German Cardiac Arrest Registry: rationale and design of G-CAR

BACKGROUND

In Germany, 70,000-100,000 persons per year suffer from out-of-hospital cardiac arrest (OHCA). Despite medical progress, survival rates with good neurological outcome remain low. For many important clinical issues, no or only insufficient evidence from randomised trials is available. Therefore, a systemic and standardised acquisition of the treatment course and of the outcome of OHCA patients is warranted.

STUDY DESIGN

The German Cardiac Arrest Registry (G-CAR) is an observational, prospective, multicentre registry. It will determine the characteristics, initial treatment strategies, invasive procedures, revascularisation therapies and the use of mechanical circulatory support devices with a focus on extracorporeal cardiopulmonary resuscitation. A special feature is the prospective 12-month follow-up evaluating mortality, neurological outcomes and several patient-reported outcomes in the psychosocial domain (health-related quality of life, cognitive impairment, depression/anxiety, post-traumatic stress disorder and social reintegration). In a pilot phase of 24 months, 15 centres will include approximately 400 consecutive OHCA patients ≥ 18 years. Parallel to and after the pilot phase, scaling up of G-CAR to a national level is envisaged.

CONCLUSION

G-CAR is the first national registry including a long-term follow-up for adult OHCA patients. Primary aim is a better understanding of the determinants of acute and long-term outcomes with the perspective of an optimised treatment.

TRIAL REGISTRY

NCT05142124. German Cardiac Arrest Registry (G-CAR).

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.

Association between prehospital advanced life support by emergency medical services personnel and neurological outcomes among adult out-of-hospital cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation: A secondary analysis of the SAVE-J II study

Study Objective

Early deployment of extracorporeal cardiopulmonary resuscitation (ECPR) is critical in treating refractory out-of-hospital cardiac arrest (OHCA) patients who are potential candidates for ECPR. The effect of prehospital advanced life support (ALS), including epinephrine administration or advanced airway, compared with no ALS in this setting remains unclear. This study's objective was to determine the association between any prehospital ALS care and outcomes of patients who received ECPR with emergency medical services-treated OHCA.

Methods

This was a secondary analysis of data from the Study of Advanced Cardiac Life Support for Ventricular Fibrillation with Extracorporeal Circulation in Japan (SAVE-J) II study. Patients were separated into 2 groups-those who received prehospital ALS (ALS group) and those did not receive prehospital ALS (no ALS group). Multiple logistic regression analysis was used to investigate the association between prehospital ALS and favorable neurological outcomes (defined as Cerebral Performance Category scores 1-2) at hospital discharge.

Results

A total of 1289 patients were included, with 644 patients in the ALS group and 645 patients in the no ALS group. There were fewer favorable neurological outcomes at hospital discharge in the ALS group compared with the no ALS group (10.4 vs 19.8%, p <0.001). A multiple logistic regression analysis revealed that any prehospital ALS care (adjusted odds ratios 0.47; 95% confidence interval 0.34-0.66; p <0.001) was associated with unfavorable neurological outcomes at hospital discharge.

Conclusion

Prehospital ALS was associated with worse neurological outcomes at hospital discharge in patients treated with ECPR for OHCA. Further prospective studies are required to determine the clinical implications of these findings.

Extracorporeal cardiopulmonary resuscitation for adult out-of-hospital cardiac arrest patients: time-dependent propensity score-sequential matching analysis from a nationwide population-based registry

BACKGROUND

There is inconclusive evidence regarding the effectiveness of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) patients. We aimed to evaluate the association between ECPR and neurologic recovery in OHCA patients using time-dependent propensity score matching analysis.

METHODS

Using a nationwide OHCA registry, adult medical OHCA patients who underwent CPR at the emergency department between 2013 and 2020 were included. The primary outcome was a good neurological recovery at discharge. Time-dependent propensity score matching was used to match patients who received ECPR to those at risk for ECPR within the same time interval. Risk ratios (RRs) and 95% confidence intervals (CIs) were estimated, and stratified analysis by the timing of ECPR was also performed.

RESULTS

Among 118,391 eligible patients, 484 received ECPR. After 1:4 time-dependent propensity score matching, 458 patients in the ECPR group and 1832 patients in the no ECPR group were included in the matched cohort. In the matched cohort, ECPR was not associated with good neurological recovery (10.3% in ECPR and 6.9% in no ECPR; RR [95% CI] 1.28 [0.85-1.93]). In the stratified analyses according to the timing of matching, ECPR with a pump-on within 45 min after emergency department arrival was associated with favourable neurological outcomes (RR [95% CI] 2.51 [1.33-4.75] in 1-30 min, 1.81 [1.11-2.93] in 31-45 min, 1.07 (0.56-2.04) in 46-60 min, and 0.45 (0.11-1.91) in over 60 min).

CONCLUSIONS

ECPR itself was not associated with good neurological recovery, but early ECPR was positively associated with good neurological recovery. Research on how to perform ECPR at an early stage and clinical trials to evaluate the effect of ECPR is warranted.

Impact of bystander cardiopulmonary resuscitation on neurological outcomes in patients undergoing veno-arterial extracorporeal membrane oxygenation

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) requires a large amount of economic and human resources. The presence of bystander cardiopulmonary resuscitation (CPR) was focused on selecting appropriate V-A ECMO candidates.

RESULT

This study retrospectively enrolled 39 patients with V-A ECMO due to out-of-hospital cardiac arrest (CA) between January 2010 and March 2019. The introduction criteria of V-A ECMO included the following: (1) < 75 years old, (2) CA on arrival, (3) < 40 min from CA to hospital arrival, (4) shockable rhythm, and (5) good activity of daily living (ADL). The prescribed introduction criteria were not met by 14 patients, but they were introduced to V-A ECMO at the discretion of their attending physicians and were also included in the analysis. Neurological prognosis at discharge was defined using The Glasgow-Pittsburgh Cerebral Performance and Overall Performance Categories of Brain Function (CPC). Patients were divided into good or poor neurological prognosis (CPC ≤ 2 or ≥ 3) groups (8 vs. 31 patients). The good prognosis group had a significantly larger number of patients who received bystander CPR (p = 0.04). The mean CPC at discharge was compared based on the combination with the presence of bystander CPR and all five original criteria. Patients who received bystander CPR and met all original five criteria showed significantly better CPC than patients who did not receive bystander CPR and did not meet some of the original five criteria (p = 0.046).

CONCLUSION

Considering the presence of bystander CPR help in selecting the appropriate candidate of V-A ECMO among out-of-hospital CA cases.

Extracorporeal Cardiopulmonary Resuscitation-A Chance for Survival after Sudden Cardiac Arrest

Extracorporeal membrane oxygenation (ECMO) is an increasingly popular method for the treatment of patients with life-threatening conditions. The case we have described is characterized by the effectiveness of therapy despite resuscitation lasting more than one hour. A 3.5-year-old girl with a negative medical history was admitted to the Department of Cardiology due to ectopic atrial tachycardia. It was decided to perform electrical cardioversion under intravenous anaesthesia. During the induction of anaesthesia, cardiac arrest with pulseless electrical activity (PEA) occurred. Despite resuscitation, a permanent hemodynamically effective heart rhythm was not achieved. Due to prolonged resuscitation (over one hour) and persistent PEA, it was decided to use veno-arterial extracorporeal membrane oxygenation. After three days of intensive ECMO therapy, hemodynamic stabilization was achieved. The time of implementing ECMO therapy and assessment of the initial clinical status of the patient should be emphasized.

E-CPR in Cardiac Arrest due to Accidental Hypothermia Using Intensivist Cannulators: A Case Series of Nine Consecutive Patients

Background: Severe accidental hypothermia (AH) accounts for over 1300 deaths/year in the United States. Early extracorporeal life support (ECLS) is recommended for hypothermic cardiac arrest. We describe the use of a rapid-deployment extracorporeal cardiopulmonary resuscitation (E-CPR) team using intensivist physicians (IPs) as cannulators and report the outcomes of consecutive patients cannulated for ECLS to manage cardiac arrest due to AH. Methods: We reviewed all patients managed with veno-arterial (V-A) ECLS for hypothermic cardiac arrest between January 1, 2017 and November 1, 2021. For each patient- age, sex, cause of hypothermia, initial core temperature, initial rhythm, time from arrest to cannulation, cannula configuration, pH, lactate, potassium, cannulation complications, duration of ECLS, hospital length of stay, mortality, and cerebral performance category (CPC) at discharge were reviewed. Results: Nine consecutive patients were identified that underwent V-A ECLS for cardiac arrest due to AH. Seven (78%) were witnessed arrests. Initial rhythm was ventricular fibrillation (VF) in eight patients and pulseless electrical activity (PEA) in one. The mean initial core temperature was 23.8 degrees Celsius. The mean time from arrest to cannulation was 58 min (range 17 to 251 min). There were no complications related to cannulation. The mean duration of ECLS was 39.1 h. All nine patients were discharged alive with a Cerebral Performance score of one or two. Conclusion: In this case series of consecutive patients reporting intensivist-deployed E-CPR for cardiac arrest due to AH, all patients survived to discharge with a favorable neurologic outcome. A rapidly available E-CPR team utilizing intensivist cannulators may improve outcomes in patients with cardiac arrest due to AH.

The Effects of Extracorporeal Cardiopulmonary Resuscitation According to Covariate Adjustment

This study compared the effects of extracorporeal cardiopulmonary resuscitation (ECPR) using propensity-score matching (PSM) analyses. A nationwide registry of out-of-hospital cardiac arrest (OHCA) patients in Korea between 2013 and 2016 was used. Patients with OHCA aged ≥15 years with cardiac etiology and resuscitation time >30 minutes were enrolled. Resuscitation-related variables before the initiation of ECPR were included. Two PSM analyses were performed separately, with and without post-ECPR variables. The primary outcome (PO) was a favorable neurologic outcome at hospital discharge. The rate of PO was 8.1% (13/161) in the ECPR group and 1.5% (247/16,489) in the conventional CPR (CCPR) group. In the matched cohort with post-ECPR variables, there was no significant difference in the rate of PO between the ECPR and CCPR groups (7.9% vs. 7.9%; p = 0.982). In the matched cohort without post-ECPR variables, the rate of PO was higher in the ECPR group than that in the CCPR group (8.3% vs. 3.6%; p = 0.012). PSM analysis without post-ECPR variables compared outcomes of all patients experiencing OHCA and treated with ECPR versus CCPR, which showed better neurologic outcomes for ECPR. PSM analysis with post-ECPR variables compared outcomes between ECPR survivors and CCPR survivors, which exhibited similar neurologic outcomes.

Regional Cerebral Oxygen Saturation to Predict Favorable Outcome in Extracorporeal Cardiopulmonary Resuscitation: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis aimed to investigate the role of regional cerebral oxygen saturation (rSO₂) in predicting survival and neurologic outcomes after extracorporeal cardiopulmonary resuscitation (ECPR).

DESIGN

The study authors performed a systematic review and meta-analysis of all available literature.

SETTING

The authors searched relevant databases (Pubmed, Medline, Embase) for studies measuring precannulation rSO₂ in patients undergoing ECPR and reporting mortality and/or neurologic outcomes.

PARTICIPANTS

The authors included both in-hospital and out-of-hospital cardiac arrest patients receiving ECPR. They identified 3 observational studies, including 245 adult patients.

INTERVENTIONS

The authors compared patients with a low precannulation rSO₂ (≤15% or 16%) versus patients with a high (>15% or 16%) precannulation rSO₂. In addition, the authors carried out subgroup analyses on out-of-hospital cardiac arrest (OHCA) patients.

MEASUREMENTS AND MAIN RESULTS

A high precannulation rSO₂ was associated with an overall reduced risk of mortality in ECPR recipients (98 out of 151 patients [64.9%] in the high rSO₂ group, v 87 out of 94 patients [92.5%] in the low rSO₂ group, risk differences [RD] -0.30; 95% CI -0.47 to -0.14), and in OHCA (78 out of 121 patients [64.5%] v 82 out of 89 patients [92.1%], RD 0.30; 95% CI -0.48 to -0.12). A high precannulation rSO₂ also was associated with a significantly better neurologic outcome in the overall population (42 out of 151 patients [27.8%] v 2 out of 94 patients [2.12%], RD 0.22; 95% CI 0.13-0.31), and in OHCA patients (33 out of 121 patients [27.3%] v 2 out of 89 patients [2.25%] RD 0.21; 95% CI 0.11-0.30).

CONCLUSIONS

A low rSO₂ before starting ECPR could be a predictor of mortality and survival with poor neurologic outcomes.

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.

Prehospital Extracorporeal Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

OBJECTIVES

To evaluate the available published evidence of the effects of extracorporeal cardiopulmonary resuscitation (ECPR) in the prehospital setting on clinical outcomes in patients with out-of-hospital cardiac arrest.

DESIGN

A systematic review and meta-analysis designed according to the Preferred Reporting Items for Systematic Reviews an Meta-Analyses guidelines.

SETTING

In the prehospital setting.

PARTICIPANTS

All randomized control trials (RCTs) and observational trials using pre-hospital ECPR in adult patients (>17 years).

INTERVENTIONS

Prehospital ECPR.

MEASUREMENTS AND MAIN RESULTS

The study authors searched Medline, Embase, and PUBMED for all RCTs and observational trials. The studies were assessed for clinical, methodologic, and statistical heterogeneity. The primary outcome was survival at hospital discharge. The study outcomes were aggregated using random-effects meta-analysis of means or proportions as appropriate. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence. Four studies were included, with a total of 222 patients receiving prehospital ECPR (mean age = 51 years [95% CI 44-57], 81% of patients were male (CI 74-87), and 60% patients had a cardiac cause for their arrest (95% CI 43-76). Overall survival at discharge was 23.4% (95% CI 15.5-33.7; I² = 62%). The pooled low-flow time was 61.1 minutes (95% CI 45.2-77.0; I² = 97%). The quality of evidence was assessed to be low, and the overall risk of bias was assessed to be serious, with confounding being the primary source of bias.

CONCLUSION

No definitive conclusions can be made as to the efficacy of prehospital ECPR in refractory cardiac arrest. Higher quality evidence is required.