Refractory Out-of-hospital Cardiac Arrest Research Articles

Abstract 4135335: A randomized trial of expedited intra-arrest transfer versus more extended on-scene resuscitation for refractory out of hospital cardiac arrest: the EVIDENCE Study

Background: Refractory out-of-hospital cardiac arrest (OHCA) has poor outcomes. The benefit of expedited intra-arrest transport with ongoing resuscitation versus more extended on-scene resuscitation for refractory OHCA is not clear. Methods: In this Phase III, multi-center (15 hospitals), randomized, controlled trial conducted in Sydney, Australia, we assigned patients with refractory out-of-hospital cardiac arrest to receive either expedited intra-arrest transport, with mechanical cardiopulmonary resuscitation, to a cardiac catherization-capable hospital for coronary angiography and, where available, extracorporeal membrane oxygenation (ECMO) cardiopulmonary resuscitation (ECPR) or more extended on-scene conventional CPR (advanced cardiac life support). Eligible patients were between 18 and 70 years of age, had received bystander CPR, initial rhythm VT/VF/PEA, and did not have a return of spontaneous circulation after 15 minutes of CPR, or three rounds of resuscitation. The primary outcome was survival with a favorable neurologic outcome, defined as a Cerebral Performance Category score of 1 or 2 at hospital discharge. Analyses were performed on an intention-to-treat basis. Results: One hundred and ninety-seven (197) eligible patients were randomized (median age, 57.0 years; 77 [81%] men), 149 VT/VF (76%). Ninety-five were assigned to receive expedited transfer and 102 to receive conventional CPR. Ten patients in the expedited arms and 6 patients in the conventional arm received ECPR at hospital. At hospital discharge, 15 patients (14.7%) in the expedited transfer group (median on scene time 26 mins) were alive with a favorable neurologic outcome, as compared with 15 patients (15.8%) (median on-scene time 36 minutes). This treatment difference was small and statistically insignificant (risk difference -1.1% [95% CI: -12.2% to 10.0%]), adjusted relative risk 0.95 [p=0.87, 95% CI: 0.50 to 1.8]. Conclusions: Among patients with refractory out-of-hospital cardiac arrest, expedited intra-arrest transport did not significantly improve survival with neurologically favorable outcome at discharge compared with more extended on-scene resuscitation. However, clinically relevant differences could still be consistent with our results.

The clinical outcome reflects the heart rhythm profile after defibrillation for shockable rhythm in refractory out-of-hospital cardiac arrest

Abstract Background The prognosis of refractory out-of-hospital cardiac arrest (OHCA) is generally poor. A recent Prague OHCA study has demonstrated that an invasive approach (including extracorporeal cardiopulmonary resuscitation, ECPR) is a feasible treatment strategy in refractory OHCA. Post-hoc analysis of Prague OHCA showed that patients with initial ventricular fibrillation (VF) had manifested better clinical outcomes than those with non-shockable rhythms irrespective of cardiopulmonary resuscitation (CPR) strategy. However, initial shockable rhythm could deteriorate to a non-shockable rhythm during CPR, mainly after defibrillation. The study aimed to stratify the prognosis of patients according to rhythm profile after initial VF in refractory OHCA during pre-hospital and early hospital periods. Methods The analysis enrolled patients with a witnessed OHCA of presumed cardiac cause, with initial VF, and without early recovery of spontaneous circulation. The primary outcome was a composite of survival with Cerebral Performance in Category (CPC) 1 or 2 at 180 days. Results 155 (median age 56y, 10 % females) patients with initial VF were enrolled. The median (IQR) duration of resuscitation was 54 (33-69) minutes. Overall survival with CPC 1 or 2 was 40.4 %. 71 patients were randomized to invasive CPR arm and 84 subjects were treated with conventional CPR. Out of all invasively treated patients, ECPR (veno-arterial extracorporeal membrane oxygenation, VA ECMO) was used in 56 cases without stable recovery of spontaneous circulation and 8 patients primary allocated in conventional group. A proportion of survival with CPC 1 or 2 varied by rhythm course: ongoing VF (9 / 28; 32 %), recovery of organized rhythm (43 / 63; 68 %), documentation of pulseless electrical activity (7 / 30; 23%), and progression to asystole (4 / 34; 12 %); P < 0.05. Tables 1 and 2 show differences in primary endpoint according to rhythm profile between invasive and conventional study arms. Conclusion Deterioration of initial shockable rhythm to asystole bears a poor prognosis in refractory OHCA even when ECPR is readily available. An invasive approach (including VA ECMO) seems to be beneficial in patients with ongoing VF and with regular electrical activity regardless of effective pulsation.

Temporal trends in organ donation among cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation

AimsThis study explores the evolution of organ donation from patients treated with extracorporeal-cardiopulmonary-resuscitation (ECPR) for refractory out-of-hospital-cardiac-arrest (OHCA) and evaluates the public health benefits of a mature ECPR program. MethodsThis retrospective, single-center study included OHCA patients (2016–2023) who had mostly initial shockable rhythms and were treated with ECPR. Organ donation rates from non-survivors through these years were analyzed. The public health benefit of ECPR was determined by the ratio of the sum of survivors with Cerebral Performance Category 1–2 and non-survivors who donated at least 1 solid organ, to the total ECPR patients. Temporal trends were analyzed yearly using linear regression. ResultsOut of 419 ECPR patients presenting with refractory OHCA over the study period, 116 survived neurologically intact (27.7%). Among non-survivors (n = 303), families of 41 (13.5%) consented to organ donation (median age 51 years, 75.6% male) and organs from 38 patients were harvested, leading to 74 organ transplants to 73 recipients. The transplanted organs included 43 kidneys (58.1%), 27 livers (36.5%), 3 lungs (4%), and 1 heart (1.4%), averaging 2.4 ± 0.9 accepted organs/donor. The number of organ donors and successful transplants correlated positively with the years since the ECPR program’s initiation (ptrend = 0.009, ptrend = 0.01). Overall, 189 patients (116 survivors, 73 organ recipients) benefited from ECPR, achieving organ-failure-free survival. The cumulative public health benefit of ECPR, considering the 116 survivors and 38 donors was 36.8%. ConclusionThe public health benefits of an established ECPR program extend beyond individual ECPR patient survival, forming a new, previously under-recognized source of transplant donors.

The time-dependent yield of invasive vs. standard resuscitation strategies: A secondary analysis of the Prague out-of-hospital cardiac arrest study

BackgroundIt is unclear how invasive resuscitative protocols may impact the time-dependent prognosis of out-of-hospital cardiac arrest (OHCA) resuscitations, or the relationship between intra-arrest transport and outcomes. MethodsWe performed a secondary analysis of the Prague OHCA Study, which randomized refractory OHCAs to “invasive” (intra-arrest transport for possible ECPR initiation) vs. “standard” resuscitation strategies (predominantly performed on-scene). Between groups, we compared outcomes of the initial resuscitation and 180- and 30-day favourable neurological outcomes (CPC 1–2), and within categories based on resuscitation duration (collapse-to-ROSC/ECPR interval). We plotted the dynamic probability of favourable outcomes with increasing durations of unsuccessful resuscitation. ResultsAmong invasive and standard groups, respectively: 34/124 (27%) vs. 58/132 (44%) had sustained ROSC (difference −17%, 95%CI −5.0, −28); 38/124 (31%) vs. 24/132 (18%) had 30-day favourable neurological outcomes (difference 12%; 95%CI 2.0, 23); and 39/124 (31%) vs. 29/132 (22%) had 180-day favourable neurological outcomes (difference 9.5%; 95%CI −1.3, 20). For favourable outcome cases: standard group resuscitation durations were right-skewed within the first 60 min; for the invasive group the distribution was bimodal, extending to 77 min. For invasive- and standard-treated cases, the probability of favourable outcomes among those in refractory arrest at 30 min was 28% and 7.6%, respectively; declining to 0% at 77 and 60 min. ConclusionIn comparison to standard resuscitation, invasive strategy cases had fewer achieve sustained ROSC, however improved overall 30-day favourable neurological outcomes. While standard resuscitation yield was limited to < 60 min, invasive protocols offer a second extended window of potential successful resuscitation.

Characteristics of intracranial hemorrhage and acute aortic syndromes resuscitated with ECPR

BackgroundIntracranial hemorrhage (ICH) and acute aortic syndrome (AAS) are etiologies associated with unfavorable outcomes in patients with out-of-hospital cardiac arrest (OHCA), even with extracorporeal cardiopulmonary resuscitation (ECPR). ObjectivesThis study aimed to describe the characteristics of refractory OHCA patients resuscitated with ECPR due to ICH and AAS. MethodsThis was a descriptive study and a secondary analysis of the SAVE-J II study, which was a multicenter ECPR registry. ResultsAmong the 1589 cases, the causes of arrest were ICH in 48 patients (3%), AAS in 112 patients (7%), and cardiac causes in 1429 patients (90%). Patients in the ICH group were younger (ICH: 47 years [IQR 40–63], AAS: 68 years [IQR 59–74], cardiac causes: 61 years [IQR 50–68]; p<0.001), and had fewer signs of life on hospital arrival (ICH: 2%, AAS: 12%, cardiac causes: 19%; p = 0.001) compared to the cardiac causes group. Patients in the ICH and AAS groups were also less likely to present with an initial shockable rhythm (ICH, 19%; AAS, 27%; cardiac causes, 74%; p<0.001). Survival to hospital discharge were significantly lower in the ICH and AAS groups than in the cardiac cause group (ICH, 4%; AAS, 4%; cardiac causes, 29%; p<0.001). Of the 112 patients in the AAS group, 54 (48%) were presumptively diagnosed as cardiac etiologies before ECPR. ConclusionsICH and AAS should be considered potential causes of cardiac arrest, especially in cases with a non-shockable initial cardiac rhythm. However, differentiating them from cardiac causes of arrest remains challenging.

Association of hyperfibrinolysis with poor prognosis in refractory circulatory arrest: implications for extracorporeal cardiopulmonary resuscitation

BackgroundIdentifying candidates for extracorporeal cardiopulmonary resuscitation (eCPR) is challenging, and novel predictive markers are urgently needed. Hyperfibrinolysis is linked to tissue hypoxia and is associated with poor outcomes in out-of-hospital cardiac arrest (OHCA). Rotational thromboelastometry (ROTEM) can detect or rule out hyperfibrinolysis, and could, therefore, provide decision support for initiation of eCPR. We explored early detection of hyperfibrinolysis in patients with refractory OHCA referred for eCPR. MethodsWe analysed ROTEM results and resuscitation parameters of 57 adult patients with ongoing OHCA who presented to our ICU for eCPR evaluation. ResultsHyperfibrinolysis, defined as maximum lysis ≥15%, was present in 36 patients (63%) and was associated with higher serum lactate, lower arterial blood pH, and increased low-flow intervals. Of 42 patients who achieved return of circulation, 28 had a poor 30-day outcome. The incidence of hyperfibrinolysis was higher in the poor outcome group compared with patients with good outcomes (75% [21 of 28] vs 7.1% [1 of 14]; P<0.001). The ratio of EXTEM A5 to lactate concentration showed good predictive value in detecting hyperfibrinolysis (AUC of 0.89 [95% confidence interval 0.8–1]). ConclusionsHyperfibrinolysis was common in patients with refractory cardiac arrest, and was associated with poor prognosis. The combination of high lactate with early clot firmness values, such as EXTEM A5, appears promising for early detection of hyperfibrinolysis. This finding could facilitate decisions to perform eCPR, particularly for patients with prolonged low-flow duration but lacking hyperfibrinolysis.

The link between carotid artery stenosis and outcomes in patients with refractory out-of-hospital cardiac arrest

BackgroundMortality of out-of-hospital cardiac arrest (OHCA) remains high. Extracorporeal cardiopulmonary resuscitation (ECPR) has revolutionized OHCA treatment, but our understanding of the ECPR responder’s clinical profile is incomplete. Carotid artery stenosis (CAS) is a well-established cardiovascular disease risk factor. The impact of CAS on OHCA outcomes remains unelucidated. ObjectiveTo assess whether CAS burden affects the outcomes of OHCA patients treated with ECPR. MethodsThis study included patients with OHCA admitted for ECPR consideration, who had carotid ultrasonography performed. A numeric scale was applied to the plaque to create a CAS burden numeric scale. The primary outcome of the study was survival at discharge, compared among the different degrees of CAS. Neurologically intact survival and surrogate markers of neurologic injury were the secondary study endpoints. To assess the independent effect of CAS burden on survival to hospital discharge, we conducted a logistic regression analysis. ResultsBetween 2019 and 2023, carotid ultrasonography was performed on 163 patients who were admitted for refractory OHCA. CAS burden was equally distributed between the right and left carotid arteries. Logistic regression analysis indicated that the CAS burden was significantly associated with both overall and neurologically intact survival at discharge (p = 0.004). A linear relationship between the CAS burden and neuron-specific and S-100 levels was identified. Patients with normal carotids were significantly less likely to have encephalopathy on electroencephalograms. ConclusionCAS burden independently predicts the risk for worse survival and neurologic outcomes in patients suffering refractory OHCA who are treated with ECPR.

A protocol for the ERICA-ARREST feasibility study of Emergency Resuscitative Endovascular Balloon occlusion of the Aorta in Out-of-Hospital Cardiac Arrest

BackgroundFewer than one in ten out-of-hospital cardiac arrest (OHCA) patients survive to hospital discharge in the UK. For prehospital teams to improve outcomes in patients who remain in refractory OHCA despite advanced life support (ALS); novel strategies that increase the likelihood of return of spontaneous circulation, whilst preserving cerebral circulation, should be investigated. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) has been shown to improve coronary and cerebral perfusion during cardiopulmonary resuscitation. Early, prehospital initiation of REBOA may improve outcomes in patients who do not respond to standard ALS. However, there are significant clinical, technical, and logistical challenges with rapidly delivering prehospital REBOA in OHCA; and the feasibility of delivering this intervention in the UK urban–rural setting has not been evaluated. MethodsThe Emergency Resuscitative Endovascular Balloon Occlusion of the Aorta in Out-of-Hospital Cardiac Arrest (ERICA-ARREST) study is a prospective, single-arm, interventional feasibility study. The trial will enrol 20 adult patients with non-traumatic OHCA. The primary objective is to assess the feasibility of performing Zone I (supra-coeliac) aortic occlusion in patients who remain in OHCA despite standard ALS in the UK prehospital setting. The trial’s secondary objectives are to describe the hemodynamic and physiological responses to aortic occlusion; to report key time intervals; and to document adverse events when performing REBOA in this context. DiscussionUsing compressed geography, and targeted dispatch, alongside a well-established femoral arterial access programme, the ERICA-ARREST study will assess the feasibility of deploying REBOA in OHCA in a mixed UK urban and rural setting.Trial registration.ClinicalTrials.gov (NCT06071910), registration date October 10, 2023, https://classic.clinicaltrials.gov/ct2/show/NCT06071910

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.

Cost-effectiveness of extracorporeal cardiopulmonary resuscitation vs. conventional cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a pre-planned, trial-based economic evaluation.

When out-of-hospital cardiac arrest (OHCA) becomes refractory, extracorporeal cardiopulmonary resuscitation (ECPR) is a potential option to restore circulation and improve the patient's outcome. However, ECPR requires specific materials and highly skilled personnel, and it is unclear whether increased survival and health-related quality of life (HRQOL) justify these costs. This cost-effectiveness study was part of the INCEPTION study, a multi-centre, pragmatic randomized trial comparing hospital-based ECPR to conventional CPR (CCPR) in patients with refractory OHCA in 10 cardiosurgical centres in the Netherlands. We analysed healthcare costs in the first year and measured HRQOL using the EQ-5D-5L at 1, 3, 6, and 12 months. Incremental cost-effectiveness ratios (ICERs), cost-effectiveness planes, and acceptability curves were calculated. Sensitivity analyses were performed for per-protocol and as-treated subgroups as well as imputed productivity loss in deceased patients. In total, 132 patients were enrolled: 62 in the CCPR and 70 in the ECPR group. The difference in mean costs after 1 year was €5109 (95% confidence interval -7264 to 15 764). Mean quality-adjusted life year (QALY) after 1 year was 0.15 in the ECPR group and 0.11 in the CCPR group, resulting in an ICER of €121 643 per additional QALY gained. The acceptability curve shows that at a willingness-to-pay threshold of €80.000, the probability of ECPR being cost-effective compared with CCPR is 36%. Sensitivity analysis showed increasing ICER in the per-protocol and as-treated groups and lower probabilities of acceptance. Hospital-based ECPR in refractory OHCA has a low probability of being cost-effective in a trial-based economic evaluation.

Organ donation after extracorporeal cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest in a metropolitan cardiac arrest centre in Milan, Italy

IntroductionExtracorporeal cardiopulmonary resuscitation (ECPR) may improve survival in refractory out-of-hospital cardiac arrest (OHCA) but also expand the donor pool as these patients often become eligible for organ donation. Our aim is to describe the impact of organ donation in OHCA patients treated with ECPR in a high-volume cardiac arrest centre. MethodsRate of organ donation (primary outcome), organs harvested, a composite of patient survival with favourable neurological outcome or donation of ≥1 solid organ (ECPR benefit), and the potential total number of individuals benefiting from ECPR (survivors with favourable neurological outcome and potential recipients of one solid organ) were analysed among all-rhythms refractory OHCA patients treated with ECPR between January 2013–November 2022 at San Raffaele Hospital in Milan, Italy. ResultsAmong 307 adults with refractory OHCA treated with ECPR (95% witnessed, 66% shockable, low-flow 70 [IQR 58–81] minutes), 256 (83%) died during hospital stay, 33% from brain death. Donation of at least one solid organ occurred in 58 (19%) patients, 53 (17%) after determination of brain death and 5 (1.6%) after determination of circulatory death, contributing a total of 167 solid organs (3.0 [IQR 2.5–4.0] organs/donor). Overall, 196 individuals (29 survivors with favourable neurological outcome and 167 potential recipients of 1 solid organ) possibly benefited from ECPR. ECPR benefit composite outcome was achieved in 87 (28%) patients. Solid organ donation decreased from 19% to 16% in patients with low-flow <60 min and to 11% with low-flow <60 min and initial shockable rhythm. ConclusionsWhen ECPR fails in patients with refractory OHCA, organ donation after brain or circulatory death can help a significant number of patients awaiting transplantation, enhancing the overall benefit of ECPR. ECPR selection criteria may affect the number of potential organ donors.

Extracorporeal cardiopulmonary resuscitation outcomes for children with out-of-hospital and emergency department cardiac arrest

ObjectiveData suggest extracorporeal cardiopulmonary resuscitation (ECPR) improves survival in adult patients with refractory cardiac arrest; however, ECPR outcomes in pediatric patients with out-of-hospital cardiac arrest (OHCA) is lacking. The primary aim of this study was to characterize pediatric patients who experience OHCA or cardiac arrest in the ED (EDCA). The secondary aim was to examine associations of cardiac arrest and location of ECPR cannulation with mortality. MethodsWe performed a retrospective analysis of the Extracorporeal Life Support Organization registry. We included pediatric patients (age > 28 days to <18 years) who received ECPR for refractory OHCA or EDCA between 2010 and 2019. Patient, cardiac arrest, and ECPR cannulation characteristics were summarized. We examined associations of location of cardiac arrest and ECPR cannulation with in-hospital mortality using multivariable logistic regression. ResultsWe analyzed data from 140 pediatric patients. 66 patients (47%) experienced OHCA and 74 patients (53%) experienced EDCA. Overall survival to hospital discharge was 31% (20% OHCA survival vs. 41% EDCA survival, p = 0.008). In adjusted analyses, OHCA was associated with 3.9 times greater odds of mortality (95% confidence interval [CI] 1.61, 9.81) when compared to compared to EDCA. The location of ECPR cannulation was not associated with mortality (odds ratio 1.8, 95% CI 0.75, 4.3). ConclusionsThe use of ECPR for pediatric patients with refractory OHCA is associated with poor survival compared to patients with EDCA. Location of ECPR cannulation does not appear to be associated with mortality.

Resuscitation Update - What's New?

Perfect, uninterrupted basic life support (BLS) is the key for successful cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest (OHCA). Time plays an important role in the treatment of OHCA. This applies both to the time until the start of BLS and the reduction of all pauses during resuscitation, especially chest compressions. In 2022, the rate of bystander-CPR showed an absolute increase of 4% compared to previous years. The bystander-CPR rate is currently above 50%. Compared to OHCA in adults, cardiac arrest in children is rare in Germany. In the period from 2007 to 2021, the incidence was 3.08 per 100000 children. In addition, the etiology in children varies depending on the age group. While hypoxia is often the cause of circulatory arrest in younger children, trauma and drowning accidents are the main causes in school-age children. Different additional diagnostic and therapeutic strategies have been evaluated over the last years. Point-of-care ultrasound during resuscitation should only be performed by experienced users. Interrupting chest compressions and thus prolonging the no-flow phases must be avoided. Double sequential external defibrillation after the third shock can successfully terminate refractory ventricular fibrillation. While further studies are needed, emergency medical systems should train their teams to avoid complications. In refractory OHCA, extracorporeal CPR should be considered. In the case of in-hospital cannulation, immediate transport should be weighed against impaired chest compression quality. Therefore, transportation under CPR is only beneficial if there is an indication for further treatment.

Machine Learning Identifies Higher Survival Profile In Extracorporeal Cardiopulmonary Resuscitation.

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. Retrospective cohort study. Cardiac ICU in a Quaternary Care Center. Adults 18-75 years old with refractory OHCA caused by a shockable rhythm. 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. 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. 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. ML can develop a tiered risk model to guide ECPR patient selection with tailored arrest profiles.

Return to Work After Refractory Out-of-Hospital Cardiac Arrest in Patients Managed With or Without Extracorporeal Cardiopulmonary Resuscitation: A Nationwide Register-Based Study.

Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly used for refractory out-of-hospital cardiac arrest (OHCA). However, survivors managed with ECPR are at risk of poor functional status. The purpose of this study was to investigate return to work (RTW) after refractory OHCA. Of 44 360 patients with OHCA in the period of 2011 to 2020, this nationwide registry-based study included 805 patients with refractory OHCA in the working age (18-65 years) who were employed before OHCA (2% of the total OHCA cohort). Demographics, prehospital characteristics, status at hospital arrival, employment status, and survival were retrieved through the Danish national registries. Sustainable RTW was defined as RTW for ≥6 months without any long sick leave relapses. Median follow-up time was 4.1 years. ECPR and standard advanced cardiovascular life support were applied in 136 and 669 patients, respectively. RTW 1 year after OHCA was similar (39% versus 54%; P=0.2) and sustainable RTW was high in both survivors managed with ECPR and survivors managed with standard advanced cardiovascular life support (83% versus 85%; P>0.9). Younger age and shorter length of hospitalization were associated with RTW in multivariable Cox analysis, whereas ECPR was not. In refractory OHCA-patients employed prior to OHCA, approximately 1 out of 2 patients were employed after 1 year with no difference between patients treated with ECPR or standard advanced cardiovascular life support. Younger age and shorter length of hospitalization were associated with RTW while ECPR was not.

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

Cardiac arrest (CA) is acommon and potentially avoidable cause of death, while constituting asubstantial 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 adefinitive 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.

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

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

Extracorporeal cardiopulmonary resuscitation versus conventional cardiopulmonary resuscitation for patients with refractory out-of-hospital cardiac arrest: A retrospective propensity matching analysis.

The incidence of out-of-hospital cardiac arrest (OHCA) is high. Though extracorporeal cardiopulmonary resuscitation (ECPR) has been considered a potential treatment for refractory cardiac arrest after failure of conventional cardiopulmonary resuscitation (CCPR), the benefit of ECPR in refractory OHCA remains uncertain. In this retrospective cohort study, we included patients with refractory OHCA who visited the Emergency Department of the Aerospace Center Hospital between January 2018 and April 2023. We divided the patients into the ECPR Group and the CCPR Group. The primary endpoint of the study was the neurological function of the patients in both groups 3months after the cardiac arrest. We used propensity score matching to reduce selection bias and identified factors associated with good neurological function when OHCA was treated with ECPR by performing univariate and multivariate correlation analyses on surviving patients with good neurological function in the ECPR group. During the study period, we enrolled 133 patients, consisting of 33 in the ECPR group and 100 in the CCPR group. The survival rate of patients with good neurological function at discharge was 18.2% (6/33 cases) in the ECPR group and 9% (9/100 cases) in the CCPR group, p = .20. Three months after discharge, the survival rate of patients with good neurological function was 15.2% (5/33 cases) in the ECPR group and 8% (8/100 cases) in the CCPR group, p = .31. Using propensity score matching, we identified 22 pairs of patients for further analysis. Among these, 3months after discharge, the survival rate of patients with good neurological function was 13.6% (3/22 cases) in the ECPR group and 4.5% (1/22 cases) in the CCPR group, p = .61, and the survival rate at discharge was 18.2% (4/22 cases) in the ECPR group and 4.5% (1/22 cases) in the CCPR group, p = .34. The univariate analysis of patients with good neurological function in the ECPR group showed that time without perfusion, hypoperfusion time, and PCI treatment were associated factors affecting the prognosis of neurological function in patients, while multivariate analysis showed that hypoperfusion time was independently associated with good neurological function, with an OR (95% CI) of 1.06 (1.00-1.14) and p = .05. Our findings suggested that ECPR failed to significantly improve neurological outcome in patients with refractory OHCA; however, the small sample size in this study may be insufficient to detect clinically relevant differences. In addition, hypoperfusion time may be a key predictive factor in identifying candidates for ECPR.

Pre-hospital ECPR in an Australian metropolitan setting: a single-arm feasibility assessment—The CPR, pre-hospital ECPR and early reperfusion (CHEER3) study

IntroductionSurvival from refractory out of hospital cardiac arrest (OHCA) without timely return of spontaneous circulation (ROSC) utilising conventional advanced cardiac life support (ACLS) therapies is dismal. CHEER3 was a safety and feasibility study of pre-hospital deployed extracorporeal membrane oxygenation (ECMO) during cardiopulmonary resuscitation (ECPR) for refractory OHCA in metropolitan Australia.MethodsThis was a single jurisdiction, single-arm feasibility study. Physicians, with pre-existing ECMO expertise, responded to witnessed OHCA, age < 65 yrs, within 30 min driving-time, using an ECMO equipped rapid response vehicle. If pre-hospital ECPR was undertaken, patients were transported to hospital for investigations and therapies including emergent coronary catheterisation, and standard intensive care (ICU) therapy until either cardiac and neurological recovery or palliation occurred. Analyses were descriptive.ResultsFrom February 2020 to May 2023, over 117 days, the team responded to 709 “potential cardiac arrest” emergency calls. 358 were confirmed OHCA. Time from emergency call to scene arrival was 27 min (15–37 min). 10 patients fulfilled the pre-defined inclusion criteria and all were successfully cannulated on scene. Time from emergency call to ECMO initiation was 50 min (35–62 min). Time from decision to ECMO support was 16 min (11–26 min). CPR duration was 46 min (32–62 min). All 10 patients were transferred to hospital for investigations and therapy. 4 patients (40%) survived to hospital discharge neurologically intact (CPC 1/2).ConclusionPre-hospital ECPR was feasible, using an experienced ECMO team from a single-centre. Overall survival was promising in this highly selected group. Further prospective studies are now warranted.

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

IntroductionGrowing 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. MethodsRefractory 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. ResultsOut 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). ConclusionsPatients 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.