Effect of Intra-arrest Transport, Extracorporeal Cardiopulmonary Resuscitation, and Immediate Invasive Assessment and Treatment on Functional Neurologic Outcome in Refractory Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial

Prevalence, reasons, and timing of decisions to withhold/withdraw life-sustaining therapy for out-of-hospital cardiac arrest patients with extracorporeal cardiopulmonary resuscitation

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is rapidly becoming a common treatment strategy for patients with refractory cardiac arrest. Despite its benefits, ECPR raises a variety of ethical concerns when the treatment is discontinued. There is little information about the decision to withhold/withdraw life-sustaining therapy (WLST) for out-of-hospital cardiac arrest (OHCA) patients after ECPR.

METHODS

We conducted a secondary analysis of data from the SAVE-J II study, a retrospective, multicenter study of ECPR in Japan. Adult patients who underwent ECPR for OHCA with medical causes were included. The prevalence, reasons, and timing of WLST decisions were recorded. Outcomes of patients with or without WLST decisions were compared. Further, factors associated with WLST decisions were examined.

RESULTS

We included 1660 patients in the analysis; 510 (30.7%) had WLST decisions. The number of WLST decisions was the highest on the first day and WSLT decisions were made a median of two days after ICU admission. Reasons for WLST were perceived unfavorable neurological prognosis (300/510 [58.8%]), perceived unfavorable cardiac/pulmonary prognosis (105/510 [20.5%]), inability to maintain extracorporeal cardiopulmonary support (71/510 [13.9%]), complications (10/510 [1.9%]), exacerbation of comorbidity before cardiac arrest (7/510 [1.3%]), and others. Patients with WLST had lower 30-day survival (WLST vs. no-WLST: 36/506 [7.1%] vs. 386/1140 [33.8%], p < 0.001). Primary cerebral disorders as cause of cardiac arrest and higher severity of illness at intensive care unit admission were associated with WLST decisions.

CONCLUSION

For approximately one-third of ECPR/OHCA patients, WLST was decided during admission, mainly because of perceived unfavorable neurological prognoses. Decisions and neurological assessments for ECPR/OHCA patients need further analysis.

Outcome of Out-of-Hospital Cardiac Arrest Patients Stratified by Pre-Clinical Loading with Aspirin and Heparin: A Retrospective Cohort Analysis

Background: Out-of-hospital cardiac arrest (OHCA) has a high prevalence of obstructive coronary artery disease and total coronary occlusion. Consequently, these patients are frequently loaded with antiplatelets and anticoagulants before hospital arrival. However, OHCA patients have multiple non-cardiac causes and high susceptibility for bleeding. In brief, there is a gap in the evidence for loading in OHCA patients. Objective: The current analysis stratified the outcome of patients with OHCA according to pre-clinical loading. Material and Methods: In a retrospective analysis of an all-comer OHCA registry, patients were stratified by loading with aspirin (ASA) and unfractionated heparin (UFH). Bleeding rate, survival to hospital discharge and favorable neurological outcomes were measured. Results: Overall, 272 patients were included, of whom 142 were loaded. Acute coronary syndrome was diagnosed in 103 patients. One-third of STEMIs were not loaded. Conversely, 54% with OHCA from non-ischemic causes were pretreated. Loading was associated with increased survival to hospital discharge (56.3 vs. 40.3%, p = 0.008) and a more favorable neurological outcome (80.7 vs. 62.6% p = 0.003). Prevalence of bleeding was comparable (26.8 vs. 31.5%, p = 0.740). Conclusions: Pre-clinical loading did not increase bleeding rates and was associated with favorable survival. Overtreatment of OHCA with non-ischemic origin, but also undertreatment of STEMI-OHCA were documented. Loading without definite diagnosis of sustained ischemia is debatable in the absence of reliable randomized controlled data.

Bioinformatics and experimental analyses of glutamate receptor and its targets genes in myocardial and cerebral ischemia

BACKGROUND

There is a mutual hemodynamic and pathophysiological basis between the heart and brain. Glutamate (GLU) signaling plays an important role in the process of myocardial ischemia (MI) and ischemic stroke (IS). To further explore the common protective mechanism after cardiac and cerebral ischemic injuries, the relationship between GLU receptor-related genes and MI and IS were analyzed.

RESULTS

A total of 25 crosstalk genes were identified, which were mainly enriched in the Toll-like receptor signaling pathway, Th17 cell differentiation, and other signaling pathways. Protein-protein interaction analysis suggested that the top six genes with the most interactions with shared genes were IL6, TLR4, IL1B, SRC, TLR2, and CCL2. Immune infiltration analysis suggested that immune cells such as myeloid-derived suppressor cells and monocytes were highly expressed in the MI and IS data. Memory B cells and Th17 cells were expressed at low levels in the MI and IS data; molecular interaction network construction suggested that genes such as JUN, FOS, and PPARA were shared genes and transcription factors; FCGR2A was a shared gene of MI and IS as well as an immune gene. Least absolute shrinkage and selection operator logistic regression analysis identified nine hub genes: IL1B, FOS, JUN, FCGR2A, IL6, AKT1, DRD4, GLUD2, and SRC. Receiver operating characteristic analysis revealed that the area under the curve of these hub genes was > 65% in MI and IS for all seven genes except IL6 and DRD4. Furthermore, clinical blood samples and cellular models showed that the expression of relevant hub genes was consistent with the bioinformatics analysis.

CONCLUSIONS

In this study, we found that the GLU receptor-related genes IL1B, FOS, JUN, FCGR2A, and SRC were expressed in MI and IS with the same trend, which can be used to predict the occurrence of cardiac and cerebral ischemic diseases and provide reliable biomarkers to further explore the co-protective mechanism after cardiac and cerebral ischemic injury.

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.

Prevalence and Geographic Features of Patients Eligible for Extracorporeal Cardiopulmonary Resuscitation

OBJECTIVE

This study sought to identify Out of Hospital Cardiac Arrests (OHCA) eligible for Extracorporeal Cardiopulmonary Resuscitation (ECPR), use Geographic Information Systems (GIS) to investigate geographic patterns, and investigate if correlation between ECPR candidacy and Social Determinants of Health (SDoH) exist.

METHODS

This study is of emergency medical service (EMS) runs for OHCA to an urban medical center from January 1, 2016 to December 31, 2020. All runs were filtered to inclusion criteria for ECPR: age 18-65, initial shockable rhythm, and no return of spontaneous circulation within initial defibrillations. Address level data were mapped in a GIS. Cluster detection assessed for granular areas of high concentration. The Center for Disease Control and Prevention (CDC) Social Vulnerability Index (SVI) was overlaid. The SVI ranges from 0-1 with higher values indicating increasing social vulnerability.

RESULTS

There were 670 EMS transports for OHCA during the study period. 12.7% (85/670) met inclusion criteria for ECPR. 90% (77/85) had appropriate addresses for geocoding. Three geographic clusters of events were detected. Two were residential areas and one was concentrated over a public use area of downtown Cleveland. The SVI for these locations was 0.79, indicative of high social vulnerability. Nearly half (32/77, 41.5%) occurred in neighborhoods with the highest level of social vulnerability (SVI ≥0.9).

CONCLUSION

A significant proportion of OHCAs were eligible for ECPR based on prehospital criteria. Utilizing GIS to map and analyze ECPR patients provided insights into the locations of these events and the SDoH that may be driving risk in these places.

The Impact Of BMI On Arrest Characteristics and Survival of Patients with Out-Of-Hospital Cardiac Arrest Treated With Extracorporeal Cardiopulmonary Resuscitation

AIM

To assess the impact of body mass index (BMI) on survival to hospital discharge of patients presenting with refractory ventricular fibrillation treated with extracorporeal cardiopulmonary resuscitation. We hypothesize that due to limitations in pre-hospital care delivery, people with high BMI have worse survival after prolonged resuscitation and ECPR.

METHODS

This study is a retrospective single-centre study that included patients suffering refractory VT/VF OHCA from December 2015 to October 2021 and had a BMI calculated at hospital admission. We compared the baseline characteristics and survival between patients with obesity (>30 kg/m²) and those without (≤30kg/m²).

RESULTS

Two-hundred eighty-three patients were included in this study, and two-hundred twenty-four required mechanical support with veno-arterial extracorporeal cardiopulmonary membrane oxygenation (VA ECMO). Patients with BMI >30 (n = 133) had significantly prolonged CPR duration compared to their peers with BMI ≤30kg/m² (n = 150) and were significantly more likely to require support with VA ECMO (85.7% vs 73.3%, p = 0.015). Survival to hospital discharge was significantly higher in patients with BMI≤30 kg/m² (48% vs. 29.3%, p <0.001). BMI was an independent predictor of mortality in a multivariable logistic regression analysis. The four-year mortality rate was low and not significantly different between the two groups (p=0.32).

CONCLUSION

ECPR yields clinically meaningful long-term survival in patients with BMI>30kg/m². However, the resuscitation time is significantly prolonged, and the overall survival significantly lower compared to patients with BMI≤30 kg/m². ECPR should, therefore, not be withheld for this population, but faster transport to an ECMO capable centre is mandated to improve survival to hospital discharge.

What is the potential benefit of pre-hospital extracorporeal cardiopulmonary resuscitation for patients with an out-of-hospital cardiac arrest? A predictive modelling study

AIM

In this predictive modelling study we aimed to investigate how many patients with an out-of-hospital cardiac arrest (OHCA) would benefit from pre-hospital as opposed to in-hospital initiation of extracorporeal cardiopulmonary resuscitation (ECPR).

METHODS

A temporal spatial analysis of Utstein data was performed for all adult patients with a non-traumatic OHCA attended by three emergency medical services (EMS) covering the north of the Netherlands during a one-year period. Patients were considered potentially eligible for ECPR if they had a witnessed arrest with immediate bystander CPR, an initial shockable rhythm (or signs of life during resuscitation) and could be presented in an ECPR-centre within 45 minutes of the arrest. Endpoint of interest was defined as the hypothetical number of ECPR eligible patients after 10, 15 and 20 minutes of conventional CPR and upon (hypothetical) arrival in an ECPR-centre as a fraction of the total number of OHCA patients attended by EMS.

RESULTS

During the study period 622 OHCA patients were attended, of which 200 (32%) met ECPR eligibility criteria upon EMS arrival. The optimal transition point between conventional CPR and ECPR was found to be after 15 minutes. Hypothetical intra-arrest transport of all patients in whom no return of spontaneous circulation (ROSC) was obtained after that point (n=84) would have yielded 16/622 (2.5%) patients being potentially ECPR eligible upon hospital arrival (average low-flow time 52 minutes), whereas on-scene initiation of ECPR would have resulted in 84/622 (13.5%) potential candidates (average estimated low-flow time 24 minutes before cannulation).

CONCLUSION

Even in healthcare systems with relatively short transport distances to hospital, consideration should be given to pre-hospital initiation of ECPR for OHCA as it shortens low-flow time and increases the number of potentially eligible patients.

Intraarrest transport, extracorporeal cardiopulmonary resuscitation, and early invasive management in refractory out-of-hospital cardiac arrest: an individual patient data pooled analysis of two randomised trials

Background

Refractory out-of-hospital cardiac arrest (OHCA) treated with standard advanced cardiac life support (ACLS) has poor outcomes. Transport to hospital followed by in-hospital extracorporeal cardiopulmonary resuscitation (ECPR) initiation may improve outcomes. We performed a pooled individual patient data analysis of two randomised controlled trials evaluating ECPR based approach in OHCA.

Methods

The individual patient data from two published randomised controlled trials (RCTs) were pooled: ARREST (enrolled Aug 2019-June 2020; NCT03880565) and PRAGUE-OHCA (enrolled March 1, 2013-Oct 25, 2020; NCT01511666). Both trials enrolled patients with refractory OHCA and compared: intra-arrest transport with in-hospital ECPR initiation (invasive approach) versus continued standard ACLS. The primary outcome was 180-day survival with favourable neurological outcome (defined as Cerebral Performance Category 1-2). Secondary outcomes included: cumulative survival at 180 days, 30-day favourable neurological survival, and 30-day cardiac recovery. Risk of bias in each trial was assessed by two independent reviewers using the Cochrane risk-of-bias tool. Heterogeneity was assessed via Forest plots.

Findings

The two RCTs included 286 patients. Of those randomised to the invasive (n = 147) and standard (n = 139) groups, respectively: the median age was 57 (IQR 47-65) and 58 years (IQR 48-66), and the median duration of resuscitation was 58 (IQR 43-69) and 49 (IQR 33-71) minutes (p = 0.17). In a modified intention to treat analysis, 45 (32.4%) in the invasive and 29 (19.7%) patients in the standard arm survived to 180 days with a favourable neurological outcome [absolute difference (AD), 95% CI: 12.7%, 2.6-22.7%, p = 0.015]. Forty-seven (33.8%) and 33 (22.4%) patients survived to 180 days [HR 0.59 (0.43-0.81); log rank test p = 0.0009]. At 30 days, 44 (31.7%) and 24 (16.3%) patients had favourable neurological outcome (AD 15.4%, 5.6-25.1%, p = 0.003), 60 (43.2%), and 46 (31.3%) patients had cardiac recovery (AD: 11.9%, 0.7-23%, p = 0.05), in the invasive and standard arms, respectively. The effect was larger in patients presenting with shockable rhythms (AD 18.8%, 7.6-29.4; p = 0.01; HR 2.26 [1.23-4.15]; p = 0.009) and prolonged CPR (>45 min; HR 3.99 (1.54-10.35); p = 0.005).

Interpretation

In patients with refractory OHCA, the invasive approach significantly improved 30- and 180-day neurologically favourable survival.

Funding

None.

Extracorporeal CPR after the INCEPTION trial: No one steps twice into the same river

The use of veno-arterial extracorporeal membrane oxygenation as extracorporeal cardiopulmonary resuscitation in patients suffering out-of-hospital cardiac arrest, largely increased in the last decade despite evidence supporting this practice being limited to non-randomized studies. However, between 2020 and 2023, four randomized studies were published comparing extracorporeal cardiopulmonary resuscitation to conventional cardiopulmonary resuscitation with controversial findings that triggered great debates. In this controversy, we discuss merits and pitfalls, and provide a critical interpretation of the available evidence from randomized trials on the use of extracorporeal cardiopulmonary resuscitation, with a particular focus on the recent multi-center INCEPTION trial.

Therapeutic Effect of Argatroban During Cardiopulmonary Resuscitation and Streptokinase During Extracorporeal Cardiopulmonary Resuscitation in a Porcine Model of Prolonged Cardiac Arrest

Prolonged cardiac arrest (CA) causes microvascular thrombosis which is a potential barrier to organ reperfusion during extracorporeal cardiopulmonary resuscitation (ECPR). The aim of this study was to test the hypothesis that early intra-arrest anticoagulation during cardiopulmonary resuscitation (CPR) and thrombolytic therapy during ECPR improve recovery of brain and heart function in a porcine model of prolonged out-of-hospital CA.

DESIGN

Randomized interventional trial.

SETTING

University laboratory.

SUBJECTS

Swine.

INTERVENTIONS

In a blinded study, 48 swine were subjected to 8 minutes of ventricular fibrillation CA followed by 30 minutes of goal-directed CPR and 8 hours of ECPR. Animals were randomized into four groups (n = 12) and given either placebo (P) or argatroban (ARG; 350 mg/kg) at minute 12 of CA and either placebo (P) or streptokinase (STK, 1.5 MU) at the onset of ECPR.

MEASUREMENTS AND MAIN RESULTS

Primary outcomes included recovery of cardiac function measured by cardiac resuscitability score (CRS: range 0-6) and recovery of brain function measured by the recovery of somatosensory-evoked potential (SSEP) cortical response amplitude. There were no significant differences in recovery of cardiac function as measured by CRS between groups (p = 0.16): P + P 2.3 (1.0); ARG + P = 3.4 (2.1); P + STK = 1.6 (2.0); ARG + STK = 2.9 (2.1). There were no significant differences in the maximum recovery of SSEP cortical response relative to baseline between groups (p = 0.73): P + P = 23% (13%); ARG + P = 20% (13%); P + STK = 25% (14%); ARG + STK = 26% (13%). Histologic analysis demonstrated reduced myocardial necrosis and neurodegeneration in the ARG + STK group relative to the P + P group.

CONCLUSIONS

In this swine model of prolonged CA treated with ECPR, early intra-arrest anticoagulation during goal-directed CPR and thrombolytic therapy during ECPR did not improve initial recovery of heart and brain function but did reduce histologic evidence of ischemic injury. The impact of this therapeutic strategy on the long-term recovery of cardiovascular and neurological function requires further investigation.

Extracorporeal cardiopulmonary resuscitation dissemination and integration with organ preservation in the USA: ethical and logistical considerations

Use of extracorporeal membrane oxygenation (ECMO) in cardiopulmonary resuscitation, termed eCPR, offers the prospect of improving survival with good neurological function after cardiac arrest. After death, ECMO can also be used for enhanced preservation of abdominal and thoracic organs, designated normothermic regional perfusion (NRP), before organ recovery for transplantation. To optimize resuscitation and transplantation outcomes, healthcare networks in Portugal and Italy have developed cardiac arrest protocols that integrate use of eCPR with NRP. Similar dissemination of eCPR and its integration with NRP in the USA raise novel ethical issues due to a non-nationalized health system and an opt-in framework for organ donation, as well as other legal and cultural factors. Nonetheless, eCPR investigations are ongoing, and both eCPR and NRP are selectively employed in clinical practice. This paper delineates the most pressing relevant ethical considerations and proposes recommendations for implementation of protocols that aim to promote public trust and reduce conflicts of interest. Transparent policies should rely on protocols that separate lifesaving from organ preservation considerations; robust, centralized eCPR data to inform equitable and evidence-based allocations; uniform practices concerning clinical decision-making and resource utilization; and partnership with community stakeholders, allowing patients to make decisions about emergency care that align with their values. Proactively addressing these ethical and logistical challenges could enable eCPR dissemination and integration with NRP protocols in the USA, with the potential to maximize lives saved through both improved resuscitation with good neurological outcomes and increased organ donation opportunities when resuscitation is unsuccessful or not in accordance with individuals' wishes.

Differential diagnosis and cause-specific treatment during out-of-hospital cardiac arrest: a retrospective descriptive study

BACKGROUND

The cardiopulmonary resuscitation (CPR) guidelines recommend identifying and correcting the underlying reversible causes of out-of-hospital cardiac arrest (OHCA). However, it is uncertain how often these causes can be identified and treated. Our aim was to estimate the frequency of point of care ultrasound examinations, blood sample analyses and cause-specific treatments during OHCA.

METHODS

We performed a retrospective study in a physician-staffed helicopter emergency medical service (HEMS) unit. Data on 549 non-traumatic OHCA patients who were undergoing CPR at the arrival of the HEMS unit from 2016 to 2019 were collected from the HEMS database and patient records. We also recorded the frequency of ultrasound examinations, blood sample analyses and specific therapies provided during OHCA, such as procedures or medications other than chest compressions, airway management, ventilation, defibrillation, adrenaline or amiodarone.

RESULTS

Of the 549 patients, ultrasound was used in 331 (60%) and blood sample analyses in 136 (24%) patients during CPR. A total of 85 (15%) patients received cause-specific treatment, the most common ones being transportation to extracorporeal CPR and percutaneous coronary intervention (PCI) (n = 30), thrombolysis (n = 23), sodium bicarbonate (n = 17), calcium gluconate administration (n = 11) and fluid resuscitation (n = 10).

CONCLUSION

In our study, HEMS physicians deployed ultrasound or blood sample analyses in 84% of the encountered OHCA cases. Cause-specific treatment was administered in 15% of the cases. Our study demonstrates the frequent use of differential diagnostic tools and relatively infrequent use of cause-specific treatment during OHCA. Effect on protocol for differential diagnostics should be evaluated for more efficient cause specific treatment during OHCA.

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).

A novel cardiac arrest severity score for the early prediction of hypoxic-ischemic brain injury and in-hospital death

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) outcomes are unsatisfactory despite postcardiac arrest care. Early prediction of prognoses might help stratify patients and provide tailored therapy. In this study, we derived and validated a novel scoring system to predict hypoxic-ischemic brain injury (HIBI) and in-hospital death (IHD).

METHODS

We retrospectively analyzed Korean Hypothermia Network prospective registry data collected from in Korea between 2015 and 2018. Patients without neuroprognostication data were excluded, and the remaining patients were randomly divided into derivation and validation cohorts. HIBI was defined when at least one prognostication predicted a poor outcome. IHD meant all deaths regardless of cause. In the derivation cohort, stepwise multivariate logistic regression was conducted for the HIBI and IHD scores, and model performance was assessed. We then classified the patients into four categories and analyzed the associations between the categories and cerebral performance categories (CPCs) at hospital discharge. Finally, we validated our models in an internal validation cohort.

RESULTS

Among 1373 patients, 240 were excluded, and 1133 were randomized into the derivation (n = 754) and validation cohorts (n = 379). In the derivation cohort, 7 and 8 predictors were selected for HIBI (0-8) and IHD scores (0-11), respectively, and the area under the curves (AUC) were 0.85 (95% CI 0.82-0.87) and 0.80 (95% CI 0.77-0.82), respectively. Applying optimum cutoff values of ≥6 points for HIBI and ≥7 points for IHD, the patients were classified as follows: HIBI (-)/IHD (-), Category 1 (n = 424); HIBI (-)/IHD (+), Category 2 (n = 100); HIBI (+)/IHD (-), Category 3 (n = 21); and HIBI (+)/IHD (+), Category 4 (n = 209). The CPCs at discharge were significantly different in each category (p < 0.001). In the validation cohort, the model showed moderate discrimination (AUC 0.83, 95% CI 0.79-0.87 for HIBI and AUC 0.77, 95% CI 0.72-0.81 for IHD) with good calibration. Each category of the validation cohort showed a significant difference in discharge outcomes (p < 0.001) and a similar trend to the derivation cohort.

CONCLUSIONS

We presented a novel approach for assessing illness severity after OHCA. Although external prospective studies are warranted, risk stratification for HIBI and IHD could help provide OHCA patients with appropriate treatment.

Extracorporeal Membrane Oxygenation Then and Now; Broadening Indications and Availability

Extracorporeal membrane oxygenation (ECMO) is a life support technology provided to children to support respiratory failure, cardiac failure, or cardiopulmonary resuscitation after failure of conventional management. Over the decades, ECMO has expanded in use, advanced in technology, shifted from experimental to a standard of care, and evidence supporting its use has increased. The expanded ECMO indications and medical complexity of children have also necessitated focused studies in the ethical domain such as decisional authority, resource allocation, and equitable access.

Refractory out-of-hospital cardiac arrest and extracorporeal cardiopulmonary resuscitation: A meta-analysis of randomized trials

BACKGROUND

In adults with refractory out-of-hospital cardiac arrest, when conventional cardiopulmonary resuscitation (CPR) alone does not achieve return of spontaneous circulation, extracorporeal CPR is attempted to restore perfusion and improve outcomes. Considering the contrasting findings of recent studies, we conducted a meta-analysis of randomized controlled trials to ascertain the effect of extracorporeal CPR on survival and neurological outcome.

METHODS

Pubmed via MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched up to February 3, 2023, for randomized controlled trials comparing extracorporeal CPR versus conventional CPR in adults with refractory out-of-hospital cardiac arrest. Survival with a favorable neurological outcome at the longest follow-up available was the primary outcome.

RESULTS

Among four randomized controlled trials included, extracorporeal CPR compared with conventional CPR increased survival with favorable neurological outcome at the longest follow-up available for all rhythms (59/220 [27%] vs. 39/213 [18%]; OR = 1.72; 95% CI, 1.09-2.70; p = 0.02; I²  = 26%; number needed to treat of 9), for initial shockable rhythms only (55/164 [34%] vs. 38/165 [23%]; OR = 1.90; 95% CI, 1.16-3.13; p = 0.01; I²  = 23%; number needed to treat of 7), and at hospital discharge or 30 days (55/220 [25%] vs. 34/212 [16%]; OR = 1.82; 95% CI, 1.13-2.92; p = 0.01; I²  = 0.0%). Overall survival at the longest follow-up available was similar (61/220 [25%] vs. 34/212 [16%]; OR = 1.82; 95% CI, 1.13-2.92; p = 0.59; I²  = 58%).

CONCLUSIONS

Extracorporeal CPR compared with conventional CPR increased survival with favorable neurological outcome in adults with refractory out-of-hospital cardiac arrest, especially when the initial rhythm was shockable.

REVIEW REGISTRATION

PROSPERO CRD42023396482.

One-Year Review in Cardiac Arrest: The 2022 Randomized Controlled Trials

Cardiac arrest, one of the leading causes of death, accounts for numerous clinical studies published each year. This review summarizes the findings of all the randomized controlled clinical trials (RCT) on cardiac arrest published in the year 2022. The RCTs are presented according to the following categories: out-of- and in-hospital cardiac arrest (OHCA, IHCA) and post-cardiac arrest care. Interestingly, more than 80% of the RCTs encompassed advanced life support and post-cardiac arrest care, while no studies focused on the treatment of IHCA, except for one that, however, explored the temperature control after resuscitation in this population. Surprisingly, 9 out of 11 RCTs led to neutral results demonstrating equivalency between the newly tested interventions compared to current practice. One trial was negative, showing that oxygen titration in the immediate pre-hospital post-resuscitation period decreased survival compared to a more liberal approach. One RCT was positive and introduced new defibrillation strategies for refractory cardiac arrest. Overall, data from the 2022 RCTs discussed here provide a solid basis to generate new hypotheses to be tested in future clinical studies.

Contemporary Management of Cardiogenic Shock Complicating Acute Myocardial Infarction

Despite an improvement in pharmacological therapies and mechanical reperfusion, the outcome of patients with acute myocardial infarction (AMI) is still suboptimal, especially in patients with cardiogenic shock (CS). The incidence of CS accounts for 3-15% of AMI cases, with mortality rates of 40% to 50%. In contrast to a large number of trials conducted in patients with AMI without CS, there is limited evidence-based scientific knowledge in the CS setting. Therefore, recommendations and actual treatments are often based on registry data. Similarly, knowledge of the available options in terms of temporary mechanical circulatory support (MCS) devices is not equally widespread, leading to an underutilisation or even overutilisation in different regions/countries of these treatment options and nonuniformity in the management of CS. The aim of this article is to provide a critical overview of the available literature on the management of CS as a complication of AMI, summarising the most recent evidence on revascularisation strategies, pharmacological treatments and MCS use.

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.

Simulators and Simulations for Extracorporeal Membrane Oxygenation: An ECMO Scoping Review

High-volume extracorporeal membrane oxygenation (ECMO) centers generally have better outcomes than (new) low-volume ECMO centers, most likely achieved by a suitable exposure to ECMO cases. To achieve a higher level of training, simulation-based training (SBT) offers an additional option for education and extended clinical skills. SBT could also help to improve the interdisciplinary team interactions. However, the level of ECMO simulators and/or simulations (ECMO sims) techniques may vary in purpose. We present a structured and objective classification of ECMO sims based on the broad experience of users and the developer for the available ECMO sims as low-, mid-, or high-fidelity. This classification is based on overall ECMO sim fidelity, established by taking the median of the definition-based fidelity, component fidelity, and customization fidelity as determined by expert opinion. According to this new classification, only low- and mid-fidelity ECMO sims are currently available. This comparison method may be used in the future for the description of new developments in ECMO sims, making it possible for ECMO sim designers, users, and researchers to compare accordingly, and ultimately improve ECMO patient outcomes.

Heart Disease and Stroke Statistics-2023 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2023 Statistical Update is the product of a full year's worth of effort in 2022 by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. The American Heart Association strives to further understand and help heal health problems inflicted by structural racism, a public health crisis that can significantly damage physical and mental health and perpetuate disparities in access to health care, education, income, housing, and several other factors vital to healthy lives. This year's edition includes additional COVID-19 (coronavirus disease 2019) publications, as well as data on the monitoring and benefits of cardiovascular health in the population, with an enhanced focus on health equity across several key domains.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Selection of patients for mechanical circulatory support for refractory out-of-hospital cardiac arrest

OBJECTIVE

To describe characteristics of patients admitted with refractory cardiac arrest for possible extracorporeal cardiopulmonary resuscitation (ECPR) and gain insight into the reasons for refraining from treatment in some.

METHODS

Nationwide retrospective cohort study involving all tertiary centres providing ECPR in Denmark. Consecutive patients admitted with ongoing chest compression for evaluation for ECPR treatment were enrolled. Presenting characteristics, duration of no-flow and low-flow time, end-tidal carbon dioxide (ETCO₂), lactate and pH, and recording of reasons for refraining from ECPR documented by the treating team were recorded. Outcomes were survival to intensive care unit admission and survival to hospital discharge.

RESULTS

Of 579 patients admitted with refractory cardiac arrest for possible ECPR, 221 patients (38%) proceeded to ECPR and 358 patients (62%) were not considered candidates. Median prehospital low-flow time was 70 min (IQR 56 to 85) in ECPR patients and 62 min (48 to 81) in no-ECPR patients, p<0.001. Intra-arrest transport was more than 50 km in 92 (42%) ECPR patients and 135 in no-ECPR patients (38%), p=0.25. The leading causes for not initiating ECPR stated by the treating team were duration of low-flow time in 39%, severe metabolic derangement in 35%, and in 31% low ETCO₂. The prevailing combination of contributing factors were non-shockable rhythm, low ETCO₂, and metabolic derangement or prehospital low-flow time combined with low ETCO₂. Survival to discharge was only achieved in six patients (1.7%) in the no-ECPR group.

CONCLUSIONS

In this large nationwide study of patients admitted for possible ECPR, two-thirds of patients were not treated with ECPR. The most frequent reasons to abstain from ECPR were long duration of prehospital low-flow time, metabolic derangement and low ETCO₂.

Implementation of a regional extracorporeal membrane oxygenation program for refractory ventricular fibrillation out-of-hospital cardiac arrest

BACKGROUND

eCPR, the modality of extracorporeal membrane oxygenation (ECMO) applied in the setting of cardiac arrest, has emerged as a novel therapy which may improve outcomes in select patients with out-of-hospital cardiac arrest (OHCA). To date, implementation has been mainly limited to single academic centres. Our objective is to describe the feasibility and challenges with implementation of a regional protocol for eCPR.

METHODS

The Los Angeles County Emergency Medical Services (EMS) Agency implemented a regional eCPR protocol in July 2020, which included coordination across multiple EMS provider agencies and hospitals to route patients with refractory ventricular fibrillation (rVF) OHCA to eCPR-capable centres (ECCs). Data were entered on consecutive patients with rVF with suspected cardiac aetiology into a centralized database including time intervals, field and in-hospital care, survival and neurologic outcome.

RESULTS

From July 27, 2020 through July 31, 2022, 35 patients (median age 57 years, 6 (17%) female) were routed to ECCs, of whom 11 (31%) received eCPR and 3 (27%) treated with eCPR survived, all of whom had a full neurologic recovery. Challenges encountered during implementation included cost to EMS provider agencies for training, implementation, and purchase of automatic chest compression devices, maintenance of system awareness, hospital administrative support for staffing and equipment for the ECMO program, and interdepartmental coordination at ECCs.

CONCLUSION

We describe the successful implementation of a regional eCPR program with ongoing patient enrolment and data collection. These preliminary findings can serve as a model for other EMS systems who seek to implement regional eCPR programs.

Early Extracorporeal CPR for Refractory Out-of-Hospital Cardiac Arrest

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (CPR) restores perfusion and oxygenation in a patient who does not have spontaneous circulation. The evidence with regard to the effect of extracorporeal CPR on survival with a favorable neurologic outcome in refractory out-of-hospital cardiac arrest is inconclusive.

METHODS

In this multicenter, randomized, controlled trial conducted in the Netherlands, we assigned patients with an out-of-hospital cardiac arrest to receive extracorporeal CPR or conventional CPR (standard advanced cardiac life support). Eligible patients were between 18 and 70 years of age, had received bystander CPR, had an initial ventricular arrhythmia, and did not have a return of spontaneous circulation within 15 minutes after CPR had been initiated. The primary outcome was survival with a favorable neurologic outcome, defined as a Cerebral Performance Category score of 1 or 2 (range, 1 to 5, with higher scores indicating more severe disability) at 30 days. Analyses were performed on an intention-to-treat basis.

RESULTS

Of the 160 patients who underwent randomization, 70 were assigned to receive extracorporeal CPR and 64 to receive conventional CPR; 26 patients who did not meet the inclusion criteria at hospital admission were excluded. At 30 days, 14 patients (20%) in the extracorporeal-CPR group were alive with a favorable neurologic outcome, as compared with 10 patients (16%) in the conventional-CPR group (odds ratio, 1.4; 95% confidence interval, 0.5 to 3.5; P = 0.52). The number of serious adverse events per patient was similar in the two groups.

CONCLUSIONS

In patients with refractory out-of-hospital cardiac arrest, extracorporeal CPR and conventional CPR had similar effects on survival with a favorable neurologic outcome. (Funded by the Netherlands Organization for Health Research and Development and Maquet Cardiopulmonary [Getinge]; INCEPTION ClinicalTrials.gov number, NCT03101787.).

Temperature control in adults after cardiac arrest: a survey of current clinical practice in Germany

BACKGROUND

Temperature control is recommended after out of hospital cardiac arrest (OHCA) by international guidelines. This survey aimed to investigate current clinical practice and areas of uncertainty.

METHODS

Online survey targeting members of three medical emergency and critical care societies in Germany (April 21-June 6, 2022) assessing post-cardiac arrest temperature control management.

RESULTS

Of 341 completed questionnaires 28% (n = 97) used temperature control with normothermic target and 72% (n = 244) temperature control with hypothermic target. The definition of fever regarding patients with cardiac arrest ranged from ≥ 37.7 to 39.0 °C. Temperature control was mainly started in the ICU (80%, n = 273) and most commonly core cooling (74%, n = 254) and surface cooling (39%, n = 134) with feedback were used. Temperature control was maintained for 24 h in 18% (n = 61), 48 h in 28% (n = 94), 72 h in 42% (n = 143) and longer than 72 h in 13% (n = 43). 7% (n = 24) were using different protocols for OHCA with initial shockable and non-shockable rhythm. Additional 14% (n = 48) were using different temperature control protocols after in-hospital cardiac arrest (IHCA) compared with OHCA. Overall, 37% (n = 127) changed practice after the publication of the ERC-2021 guidelines and 33% (n = 114) after the recent publication of the revised ERC-ESICM guideline on temperature control.

CONCLUSIONS

One-third of the respondents changed clinical practice since recent guideline update. However, a majority of physicians further trusts in temperature control with a hypothermic target. Of interest, 14% used different temperature control strategies after IHCA compared with OHCA and 7% for shockable and non-shockable initial rhythm. A more individualized approach in post resuscitation care may be warranted.

Prehospital Physician Presence for Patients With out-of-Hospital Cardiac Arrest Undergoing Extracorporeal Cardiopulmonary Resuscitation: A Multicenter, Retrospective, Nationwide Observational Study in Japan (The JAAM-OHCA registry)

The effectiveness of the presence of a prehospital physician for patients with out-of-hospital cardiac arrest (OHCA) undergoing extracorporeal cardiopulmonary resuscitation (ECPR) remains unknown. In this multicenter, retrospective, observational study, we enrolled patients aged ≥18 years who developed OHCA and received ECPR. The primary outcome was the 1-month favorable neurological outcome. We estimated the impact of the presence of a prehospital physician on outcomes using a propensity score analysis with inverse probability weighting. We enrolled 1269 patients. Favorable neurological outcomes occurred in 25 of 316 (7.9%) patients with prehospital physicians and 94 of 953 (9.9%) patients without prehospital physicians. In the propensity score analysis, favorable neurological outcomes did not differ between 2 groups (odds ratio = 0.72; 95% confidence interval: 0.44-1.17). The 1-month favorable neurological outcome was not associated with the presence of a prehospital physician for patients with OHCA who underwent EPCR.

Emerging concepts in heart failure management and treatment: circulatory support with extracorporeal membrane oxygenation (ECMO)

Circulatory support with extracorporeal membrane oxygenation (ECMO) is being increasingly used in several critical situations but evidence of its impact on outcomes is inconsistent. Understanding of the specific indications and appropriate timing of implantation of this technology might lead to improved results. Indeed, the line between success and futility may be sometimes very thin when facing a patient in critical condition. New techniques with lighter, simpler and effective devices are being developed. Hence, ECMO has become an accessible technology that is being increasingly used outside of the operating room by heart failure specialists, critical care cardiologists and intensivists. Proper timing of utilization and choice of device may lead to better outcomes. We herein aim to improve this knowledge gap by conducting a literature review to provide simple information, evidence-based indications and a practical approach for cardiologists who may encounter acutely ill adult patients that may be ECMO candidates. This article is part of the Emerging concepts in heart failure management and treatment Special Issue: https://www.drugsincontext.com/special_issues/emerging-concepts-in-heart-failure-management-and-treatment.

External validation of the TiPS65 score for predicting good neurological outcomes in patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation

AIM

Estimating prognosis of patients treated with extracorporeal cardiopulmonary resuscitation (ECPR) is essential for selecting candidates. The TiPS65 score can predict neurological outcomes of patients with out-of-hospital cardiac arrest (OHCA) treated with ECPR. We aimed to perform an external validation of this score.

METHODS

Data from the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest registry, a multicentred, nationwide, prospectively registered database, were analysed. All adult patients with OHCA and shockable rhythm and treated with ECPR between January 2018 to December 2019 were included. In the TiPS65 score, age, call-to-hospital arrival time, initial cardiac rhythm at hospital arrival, and initial pH value were used as predictors. The primary outcome was 30-day survival with favourable neurological outcomes (Cerebral Performance Category 1 or 2). Discrimination, using the C-statistic, and predictive performances of each score, such as sensitivity and specificity, were investigated.

RESULTS

Of 590 included patients (517 [81.6%] men; median [interquartile range] age, 60 [50-69] years), 64 (10.8%) reported favourable neurological outcomes. The C-statistic of the TiPS65 score was 0.729 (95% confidence interval (CI): 0.672-0.786). When the cut-off of TiPS65 score was set to >1, the sensitivity and specificity were 0.906 (95%CI: 0.807-0.965) and 0.430 (95%CI: 0.387-0.473), respectively; conversely, when the cut-off was set to >3, they were 0.172 (95%CI: 0.089-0.287) and 0.971 (95%CI: 0.953-0.984), respectively.

CONCLUSIONS

The TiPS65 score shows reasonable discrimination and predictive performances. This score can be supportive in the decision-making process for the selection of eligible patients for ECPR in clinical settings.

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

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

Analyzing willingness for extracorporeal cardiopulmonary resuscitation in refractory ventricular fibrillation

Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory ventricular fibrillation/ventricular tachycardia in out-of-hospital cardiac arrest has recently been recommended for selected patients with favorable prognostic features. We aimed to identify factors affecting the willingness of emergency physicians to implement extracorporeal cardiopulmonary resuscitation (ECPR). We conducted a factorial survey with nine experimental vignettes by combining three different scene time intervals and transportation time intervals. Emergency physicians reported willingness to implement ECPR (1-100 points). Respondent characteristics that could affect the willingness were studied. Multilevel analysis of vignettes and respondent factors was conducted using a mixed-effects regression model. We obtained 486 vignette responses from 54 emergency physicians. In the case of longer scene time intervals, there was a significant difference in the willingness scores at 9 and 12 min transportation time intervals. When the pre-hospital time interval was > 40 min, emergency physicians demonstrated lower willingness to implement ECPR. Clinical experience of 15-19 years showed a significant favorable effect on willingness to implement extracorporeal membrane oxygenation (ECMO). However, the mean willingness scores of EPs for ECMO implementation were more than 75 across all vignettes. In ECPR, the prehospital time interval is an important factor, and the willingness of emergency physicians to implement ECMO could be mutually affected by scene time intervals, transportation time intervals, and total prehospital time.

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.

The Future of Cardiothoracic Surgical Critical Care Medicine as a Medical Science: A Call to Action

Cardiothoracic surgical critical care medicine (CT-CCM) is a medical discipline centered on the perioperative care of diverse groups of patients. With an aging demographic and an increase in burden of chronic diseases the utilization of cardiothoracic surgical critical care units is likely to escalate in the coming decades. Given these projections, it is important to assess the state of cardiothoracic surgical intensive care, to develop goals and objectives for the future, and to identify knowledge gaps in need of scientific inquiry. This two-part review concentrates on CT-CCM as its own subspeciality of critical care and cardiothoracic surgery and provides aspirational goals for its practitioners and scientists. In part one, a list of guiding principles and a call-to-action agenda geared towards growth and promotion of CT-CCM are offered. In part two, an evaluation of selected scientific data is performed, identifying gaps in CT-CCM knowledge, and recommending direction to future scientific endeavors.

Improving access to extracorporeal membrane oxygenation for out of hospital cardiac arrest: pre-hospital ECPR and alternate delivery strategies

BACKGROUND

The use of extracorporeal membrane oxygenation (ECPR) in refractory out-of-hospital cardiac arrest (OHCA) patients is usually implemented in-hospital. As survival in ECPR patients is critically time-dependent, alternative models in ECPR delivery could improve equity of access.

OBJECTIVES

To identify the best strategy of ECPR delivery to provide optimal patient access, to examine the time-sensitivity of ECPR on predicted survival and to model potential survival benefits from different delivery strategies of ECPR.

METHODS

We used transport accessibility frameworks supported by comprehensive travel time data, population density data and empirical cardiac arrest time points to quantify the patient catchment areas of the existing in-hospital ECPR service and two alternative ECPR strategies: rendezvous strategy and pre-hospital ECPR in Sydney, Australia. Published survival rates at different time points to ECMO flow were applied to predict the potential survival benefit.

RESULTS

With an in-hospital ECPR strategy for refractory OHCA, five hospitals in Sydney (Australia) had an effective catchment of 811,091 potential patients. This increases to 2,175,096 under a rendezvous strategy and 3,851,727 under the optimal pre-hospital strategy. Assuming earlier provision of ECMO flow, expected survival for eligible arrests will increase by nearly 6% with the rendezvous strategy and approximately 26% with pre-hospital ECPR when compared to the existing in-hospital strategy.

CONCLUSION

In-hospital ECPR provides the least equitable access to ECPR. Rendezvous and pre-hospital ECPR models substantially increased the catchment of eligible OHCA patients. Traffic and spatial modelling may provide a mechanism to design appropriate ECPR service delivery strategies and should be tested through clinical trials.

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.