Clinical characteristics and outcomes after extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients with an initial asystole rhythm

Analysis of factors associated with favorable neurological outcomes in patients with initial PEA who underwent ECPR - A secondary analysis of the SAVE-J II study

PURPOSE

This study aimed to investigate the factors of favorable neurological outcomes in patients with initial pulseless electrical activity (PEA) who underwent extracorporeal cardiopulmonary resuscitation (ECPR).

METHODS

The study analyzed data from the SAVE-J II registry, a retrospective multicenter registry involving 36 participating institutions in Japan. Patients with initial PEA were included.

RESULTS

Overall proportion of patients with favorable neurological outcomes and survival rate at hospital discharge were 8.2 % and 16.9 %, respectively. Multivariate analysis revealed that no cardiac rhythm conversion to asystole, signs of life or pupil diameter, and transient return of spontaneous circulation were significantly associated with favorable neurological outcomes. Among the cause of cardiac arrest, patients with acute coronary syndrome and pulmonary embolism had higher proportions of favorable neurological outcomes (9.7 % and 19.3 %), whereas no patients with acute aortic disease or primary cerebral disease survived. The application of strict criteria for PEA using classification and regression tree analysis resulted in favorable neurological outcomes in 32.7 % of the patients.

CONCLUSIONS

This study provides an overview of patients with PEA who underwent ECPR. Since several factors are associated with favorable neurological outcomes, patients with PEA may be candidates for ECPR if these factors are met.

Variability in patient selection criteria across extracorporeal cardiopulmonary resuscitation (ECPR) systems: A systematic review

BACKGROUND

Across the world, many systems have implemented extracorporeal cardiopulmonary resuscitation (ECPR) as a potential treatment strategy for patients in refractory cardiac arrest. To date, there are no universally accepted criteria for patient selection for ECPR. We conducted a systematic review to explore the variability in patient eligibility criteria for ECPR across systems.

METHODS

We searched the Cochrane Library(Wiley), EMBASE(OVID), and MEDLINE ALL (OVID) databases from inception to 5th February-2024 for all studies that described an ECPR system and where the system eligibility criteria was described. A combination of predetermined search terms was used to identify relevant articles. We conducted forward and backward citation tracking to identify any further relevant articles.

RESULTS

Our search identified 12,503 articles of which 167 articles were found to be potentially eligible. Seventy-seven articles were further excluded as they described the same ECPR system as another study. We finally included 90 studies describing a total of 93 ECPR systems. The eligibility criteria for ECPR differed among the included systems. Across systems, ECPR eligibility criteria included age (n=75, 80.7%), arrest witnessed status (n=64, 68.8%), any initial rhythm (n=55, 59.1%), and bystander CPR (n=33, 35.5%). Within criteria, we observed marked variability. The age cut-off varied from 50 to 80 years, with the most common age cut-off being 75 years and 18 (19.3%) systems having no cut-off. Whilst most systems limited ECPR to shockable rhythms (n=28,30.1%), some systems included shockable rhythms and/or PEA only (n=10,10.8%).

CONCLUSION

We observed marked variability across systems in the eligibility criteria for potential ECPR patients. There is a need for further work to identify the optimum ECPR selection criteria.

REVIEW REGISTRATION

PROSPERO (CRD42023451109).

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.

External Validation of the CAST and rCAST Score in Patients With Out-of-Hospital Cardiac Arrest Who Underwent Extracorporeal Cardiopulmonary Resuscitation: A Secondary Analysis of the SAVE-J II Study

BACKGROUND

Risk stratification is important in patients with post-cardiac arrest syndrome. The Post-Cardiac Arrest Syndrome for Therapeutic Hypothermia (CAST) and revised CAST (rCAST) scores have been well validated for predicting neurological outcomes, particularly for conventionally resuscitated patients with post-cardiac arrest syndrome. However, no studies have evaluated patients undergoing extracorporeal cardiopulmonary resuscitation.

METHODS AND RESULTS

Adult patients with out-of-hospital cardiac arrest who underwent extracorporeal cardiopulmonary resuscitation were analyzed in this retrospective observational multicenter cohort study. We validated the accuracy of the CAST/rCAST scores for predicting neurological outcomes at 30 days. Moreover, we compared the predictive performance of these scores with the TiPS65 risk score derived from patients with out-of-hospital cardiac arrest who were resuscitated using extracorporeal cardiopulmonary resuscitation. A total of 1135 patients were analyzed. The proportion of patients with favorable neurological outcomes was 16.6%. In the external validation, the area under the receiver operating characteristic curve of the CAST score was significantly higher than that of the rCAST score (area under the receiver operating characteristic curve 0.677 versus 0.603; P<0.001), but there was no significant difference with that of the TiPS65 score (versus 0.633; P=0.154). Both CAST/rCAST risk scores showed good calibration (Hosmer-Lemeshow test: P=0.726 and 0.674), and the CAST score showed significantly better predictability in net reclassification compared with the rCAST (P<0.001) and TiPS65 scores (P=0.001).

CONCLUSIONS

The prognostic accuracy of the CAST score was significantly better than that of other risk scores in net reclassification. The CAST score may help to predict neurological outcomes in patients with out-of-hospital cardiac arrest who undergo extracorporeal cardiopulmonary resuscitation. However, the predictive value of the CAST score was not sufficiently high for clinical application.

REGISTRATION

URL: https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000041577; Unique identifier: UMIN000036490.

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.

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.