Optimizing Outcomes After Out-of-Hospital Cardiac Arrest With Innovative Approaches to Public-Access Defibrillation: A Scientific Statement From the International Liaison Committee on Resuscitation.

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Variation in practice for out-of-hospital cardiac arrest treated with percutaneous coronary intervention in England and Wales.

OBJECTIVES: We assessed the association between total center volume, operator volume, and out-of-hospital cardiac arrest (OHCA) percutaneous coronary intervention (PCI) volume. BACKGROUND: Variations between OHCA PCI volume, hospital total PCI, and primary PCI volume are not well studied and are unlikely to be clinically justifiable. METHODS: Patients undergoing PCI for the acute coronary syndrome (ACS) between January 1, 2014, and March 31, 2019, in England and Wales were grouped as OHCA PCI and non-OHCA PCI. Spearman's correlation was used to determine the degree of correlation between each hospital PCI volume and OHCA PCI volume. RESULTS: Out of 250,088 PCI procedures undertaken for ACS, 12,016 (4.8%) were performed for OHCA, and 238,072 (95.2%) were non-OHCA PCI procedures. The OHCA PCI group were younger [mean age (SD) 63.2 (12.3) and 65.6 (12.5, p < 0.001)], less likely to be female (20.2% vs. 26.9%, p < 0.001) or Black, Asian, and Minority Ethnicity (11.5% vs. 14.8%, p < 0.001) compared to the non-OHCA PCI group. Although there was a degree of correlation between total PCI and OHCA PCI, there was wide variation for both ACS cohort (Spearman correlation R2 = 0.50) and total PCI volume (Spearman correlation R2 = 0.60). Furthermore, the correlation between primary PCI volume and OHCA PCI within centers was weak (R2 = 0.10). Similarly, wide variations between operator PCI volume and OHCA PCI volume were observed. CONCLUSION: These national data demonstrate wide variation in the practice of OHCA PCI both between centers and individuals. These variations are not expected according to clinical factors and require further investigation.

Speed of cooling after cardiac arrest in relation to the intervention effect: a sub-study from the TTM2-trial.

BACKGROUND: Targeted temperature management (TTM) is recommended following cardiac arrest; however, time to target temperature varies in clinical practice. We hypothesised the effects of a target temperature of 33 °C when compared to normothermia would differ based on average time to hypothermia and those patients achieving hypothermia fastest would have more favorable outcomes. METHODS: In this post-hoc analysis of the TTM-2 trial, patients after out of hospital cardiac arrest were randomized to targeted hypothermia (33 °C), followed by controlled re-warming, or normothermia with early treatment of fever (body temperature, ≥ 37.8 °C). The average temperature at 4 h (240 min) after return of spontaneous circulation (ROSC) was calculated for participating sites. Primary outcome was death from any cause at 6 months. Secondary outcome was poor functional outcome at 6 months (score of 4-6 on modified Rankin scale). RESULTS: A total of 1592 participants were evaluated for the primary outcome. We found no evidence of heterogeneity of intervention effect based on the average time to target temperature on mortality (p = 0.17). Of patients allocated to hypothermia at the fastest sites, 71 of 145 (49%) had died compared to 68 of 148 (46%) of the normothermia group (relative risk with hypothermia, 1.07; 95% confidence interval 0.84-1.36). Poor functional outcome was reported in 74/144 (51%) patients in the hypothermia group, and 75/147 (51%) patients in the normothermia group (relative risk with hypothermia 1.01 (95% CI 0.80-1.26). CONCLUSIONS: Using a hospital's average time to hypothermia did not significantly alter the effect of TTM of 33 °C compared to normothermia and early treatment of fever.

Survival after Resuscitated Out-of-Hospital Cardiac Arrest in Patients with Paramedic-Identified ST-Segment Elevation Myocardial Infarction Treated with Primary Percutaneous Coronary Intervention.

Background: ST-segment elevation myocardial infarction (STEMI) is a common cause of out-of-hospital cardiac arrest (OHCA). For these patients, urgent angiography and revascularization is an important treatment goal. There is a lack of data on the prognosis of STEMI patients after OHCA, who are diagnosed and treated by paramedics prior to hospital transport for primary percutaneous coronary intervention (PCI). Methods: Included were adult STEMI patients identified and treated by paramedics in Queensland (Australia) from January 2016 to December 2019, transported to a hospital for primary PCI, and receiving primary PCI. Patients were grouped into those with resuscitated OHCA and those without OHCA. Clinically-important time intervals, angiographic and clinical profiles, and survival were described. Results: Patients with OHCA had longer time intervals from prehospital STEMI identification to reperfusion than those without OHCA (median 97 versus 87 mins, p = 0.001). The former had higher rates of cardiac arrhythmia history (50.5 versus 12.4%, p < 0.001), classified low left ventricular ejection fraction on admission (64.9 versus 50.1%, p = 0.006), and cardiogenic shock (5.2 versus 1.2%, p = 0.011) than the latter. A significantly higher proportion of patients with OHCA had multiple diseased vessels (16.9 versus 8.3%, p = 0.005). In-hospital, 30-day, and one-year mortality was low, being 4.1%, 4.1% and 5.2%, respectively, for STEMI patients with OHCA. The corresponding figures for those without OHCA were 1.6%, 1.8% and 3.3%, respectively. Conclusions: Survival in paramedic-identified STEMI patients treated with primary PCI following OHCA resuscitation was high. Rapid angiography and reperfusion are critical in these patients.

How effective is extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest? A systematic review and meta-analysis.

BACKGROUND: Extracorporeal cardiopulmonary resuscitation (ECPR) has gained increasing as a promising but resource-intensive intervention for out-of-hospital cardiac arrest (OHCA). There is little data to quantify the impact of this intervention and the patients likely to benefit from its use. We conducted a meta-analysis of the literature to assess the survival benefit associated with ECPR for OHCA. METHODS: We searched PubMed, Embase, and Scopus databases to identify relevant observational studies and randomized control trials. We used the Newcastle-Ottawa Scale and Cochrane risk-of-bias tool to assess studies' quality. We performed random-effects meta-analysis for the primary outcome of survival to hospital discharge and used meta-regressions to assess heterogeneity. RESULTS: We identified 1287 articles, reviewed the full text of 209 and included 44 in our meta-analysis. Our analysis included 3097 patients with OHCA. Patients' mean age was 52, 79% were male, and 60% had primary ventricular fibrillation/ventricular tachycardia arrest. We identified a survival-to-discharge rate of 24%; 18% survived with favorable neurologic function. 30- and 90-days survival rates were both around 18%. The majority of included articles were high quality studies. CONCLUSIONS: Extracorporeal cardiopulmonary resuscitation is a promising but resource-intensive intervention that may increase rates of survival to hospital discharge among patients who experience OHCA.

Transitioning to Web-Based Learning in Basic Life Support Training During the COVID-19 Pandemic to Battle the Fear of Out-of-Hospital Cardiac Arrest: Presentation of Novel Methods.

Ongoing training in the area of basic life support aims to encourage and sustain the willingness to act in out-of-hospital cardiac arrest situations among first aiders. The contribution of witnesses and first aiders has diminished rapidly, as suspicion associated with the COVID-19 pandemic has risen. In this paper, we present teaching methods from the medical education field to create a new teaching-learning process for sustaining the prehospital involvement of first aiders and encourage new first aiders. The most important benefit-improving outcomes-can be achieved by introducing a variety of teaching-learning methods and formative assessments that provide participants with immediate feedback to help them move forward in the basic life support course. The new reality of web-based learning that has been introduced by the pandemic requires an innovative approach to traditional training that involves techniques and methods that have been proven to be useful in other fields.

Esmolol in the management of pre-hospital refractory ventricular fibrillation: A systematic review and meta-analysis.

BACKGROUND: Esmolol has been proposed as a viable adjunctive therapy for pre-hospital refractory ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT). OBJECTIVES: We performed a systematic review and meta-analysis to assess the effectiveness of esmolol on pre-hospital refractory VF/pVT, compared with standard of care. METHODS: MEDLINE, Embase, Scopus, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched for eligible studies. Two investigators independently extracted relevant data and assessed the methodological quality of each included study using the ROBINS-I tool. The quality of evidence for summary estimates was assessed according to GRADE guidelines. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) for each outcome of interest were calculated. RESULTS: The search yielded 3253 unique records, of which two studies were found to be in accordance with the research purpose, totaling 66 patients, of whom 33.3% (n = 22) received esmolol. Additional evidence was provided in the paper but was not relevant to the analysis and was therefore not included. Esmolol was likely associated with an increased rate of survival to discharge (RR 2.82, 95% CI 1.01-7.93, p = 0.05) (GRADE: Very low) and survival with favorable neurological outcome (RR 3.44, 95% CI 1.11-10.67, p = 0.03) (GRADE: Very low). Similar results were found for return of spontaneous circulation (ROSC) (RR 2.63, 95% CI 1.37-5.07, p = 0.004) (GRADE: Very low) and survival to intensive care unit (ICU)/hospital admission (RR 2.63, 95% CI 1.37-5.07, p = 0.004) (GRADE: Very low). CONCLUSION: The effectiveness of esmolol for refractory VF/pVT remains unclear. Trial sequential analysis (TSA) indicates that the evidence is inconclusive and that further trials are required in order to reach a conclusion. Therefore, it is imperative to continue to accumulate evidence in order to obtain a higher level of scientific evidence.

The efficacy and safety of pre-hospital cooling after out-of-hospital cardiac arrest: a systematic review and meta-analysis.

BACKGROUND: Mild therapeutic hypothermia (TH), or targeted temperature management, improves survival and neurological outcomes in patients after out-of-hospital cardiac arrest (OHCA). International guidelines strongly support initiating TH for all eligible individuals presenting with OHCA; however, the timing of cooling initiation remains uncertain. This systematic review and meta-analysis was conducted with all available randomised controlled trials (RCTs) included to explore the efficacy and safety of initiating pre-hospital TH in patients with OHCA. METHODS: The MEDLINE and Cochrane databases were searched from inception to October 2017. Inclusion criteria for full-text review included RCTs comparing pre-hospital TH with no pre-hospital TH after cardiac arrest, patients > 14 years of age with documented cardiac arrest from any rhythm, and outcome data that included survival to hospital discharge and temperature at hospital arrival. Results of retrieved studies were compared through meta-analysis using random effects modelling. RESULTS: A total of 10 trials comprising 4220 patients were included. There were no significant differences between the two arms for the primary outcome of neurological recovery (risk ratio [RR] 1.04, 95% CI 0.93-1.15) or the secondary outcome of survival to hospital discharge (RR 1.01, 95% CI 0.92-1.11). However, there was a significantly lower temperature at hospital arrival in patients receiving pre-hospital TH (mean difference - 0.83, 95% CI - 1.03 to - 0.63). Pre-hospital TH significantly increased the risk of re-arrest (RR 1.19, 95% CI 1.00 to 1.41). No survival differences were observed among subgroups of patients who received intra-arrest TH vs post-arrest TH or who had shockable vs non-shockable rhythms. CONCLUSIONS: Pre-hospital TH after OHCA effectively decreases body temperature at the time of hospital arrival. However, it does not improve rates of survival with good neurological outcome or overall survival and is associated with increased rates of re-arrest.

Uncontrolled Donation After Circulatory Determination of Death: A Systematic Ethical Analysis.

Uncontrolled donation after circulatory determination of death (uDCDD) refers to organ donation after a refractory cardiac arrest. We analyzed ethical issues raised by the uDCDD protocols of France, Madrid, and New York City. We recommend: (1) Termination of resuscitation (TOR) guidelines need refinement, particularly the minimal duration of resuscitation efforts before considering TOR; (2) Before enrolling in an uDCDD protocol, physicians must ascertain that additional resuscitation efforts would be ineffective; (3) Inclusion in an uDCDD protocol should not be made in the outpatient setting to avoid error and conflicts of interest; (4) The patient's condition should be reassessed at the hospital and reversible causes treated; (5) A no-touch period of at least 10 minutes should be respected to avoid the risk of autoresuscitation; (6) Once death has been determined, no procedure that may resume brain circulation should be used, including cardiopulmonary resuscitation, artificial ventilation, and extracorporeal membrane oxygenation; (7) Specific consent is required prior to entry into an uDCDD protocol; (8) Family members should be informed about the goals, risks, and benefits of planned uDCDD procedures; and (9) Public information on uDCDD is desirable because it promotes public trust and confidence in the organ donation system.

Epidemiology of Out-of-Hospital Cardiac Arrest Due to Suffocation Focusing on Suffocation Due to Japanese Rice Cake: A Population-Based Observational Study From the Utstein Osaka Project.

BACKGROUND: Japanese rice cake ("mochi") is a major cause of food-choking accidents in Japan. However, the epidemiology of out-of-hospital cardiac arrests (OHCAs) due to suffocation caused by rice cakes is poorly understood. METHODS: OHCA data from 2005 to 2012 were obtained from the population-based OHCA registry in Osaka Prefecture. Patients aged ≥20 years who experienced OHCA caused by suffocation that occurred before the arrival of emergency-medical-service (EMS) personnel were included. Patient characteristics, prehospital interventions, and outcomes were compared based on the cause of suffocation (rice cake and non-rice-cake). The primary outcome was 1-month survival after OHCA. RESULTS: In total, 46 911 adult OHCAs were observed during the study period. Of the OHCAs, 7.0% (3,294/46,911) were due to suffocation, with choking due to rice cake as the cause in 9.5% of cases (314/3,294), and of these, 24.5% (77/314) occurred during the first 3 days of the New Year. In crude analysis, 1-month survival was 17.2% (54/314) in those with suffocation caused by rice cake and 13.4% (400/2,980) in those with suffocation due to other causes. In the multivariable analysis for all-cause suffocation, younger age, arrest witnessed by bystanders, and earlier EMS response time were significantly related to better 1-month survival. CONCLUSION: Approximately 10% of OHCAs due to suffocation were caused by rice-cake choking, and 25% of these occurred during the first 3 days of the New Year. Further efforts for establishing preventive measures as well as improving the early recognition of choking and encouraging bystanders to call EMS sooner are needed.

The effect of team-based CPR on outcomes in out of hospital cardiac arrest patients: A meta-analysis.

OBJECTIVES: The objective of this systematic review and meta-analysis was to determine the effects of team cardiopulmonary resuscitation (CPR) on outcomes of patients with out-of-hospital cardiac arrest (OHCA). METHODS: A systematic literature review was performed using PubMed, EMBASE, and the Cochrane database to identify relevant articles for this meta-analysis. All studies that described the implementation of team CPR performed by emergency medical services for OHCA patients with presumed cardiac etiology were included in this study. Outcomes included return of spontaneous circulation (ROSC), survival to hospital discharge, and good neurological recovery. RESULTS: A total of 2504 studies were reviewed. After excluding studies according to exclusion criteria, 4 studies with 15,455 OHCA patients were included in this study. The odds of survival and neurologic recovery for patients who received team CPR were higher than those for patients who did not (survival odds ratio [OR]: 1.68; 95% confidence interval [CI]: 1.48-1.91; neurologic recovery OR: 1.52; 95% CI: 1.31-1.77). There was no significant difference in the odds of ROSC between the two patient groups (OR: 1.59; 95% CI: 0.76-3.33). CONCLUSIONS: In this meta-analysis, team CPR improved the outcomes of OHCA patients, consistently increasing their odds of survival to discharge and neurologic recovery.

Sudden cardiac death.

Introduction: Sudden cardiac arrest continues to be the leading cause of death in the industrialized world. Sources of data: Original papers, reviews and guidelines. Areas of agreement: Community programs for lay bystander cardiopulmonary resuscitation (CPR) and automatic external defibrillation improve outcomes. Post-arrest care, including targeted temperature management (TTM) combined with early coronary angiography and percutaneous coronary intervention, is helpful for those suffering cardiac arrest during an ST-segment elevation myocardial infarction. Areas of controversy: (1) The optimal approach to encourage lay bystanders to assist with resuscitation efforts. (2) Whether TTM combined with early coronary angiography is cost effective for those without ST elevation on their post-arrest ECG is unknown. Growing points: Increasing data show that chest compression-only CPR is preferred by lay rescuers and improves local survival rates. Areas timely for developing research: Randomized clinical trials are underway to examine the utility of early coronary angiography in the treatment of post-arrest patients without ST-segment elevation.

Expanded application of wearable cardioverter defibrillators beyond current guidelines: proposal for a European register explained through single clinical scenarios.

The wearable cardioverter defibrillator (WCD) is becoming a more and more widely used instrument for the prevention of sudden cardiac death of patients either with a secondary prevention implantable cardioverter defibrillator indication or with a transient high risk of sudden cardiac death. Although clinical practice has demonstrated a benefit of protecting patients for a period as long as 3-6 months with such devices, the current European guidelines concerning ventricular arrhythmias and sudden cardiac death are still extremely restrictive in the patient selection in part because of the costs derived from such a prevention device, in part because of the lack of robust randomised trials.To illustrate expanded use cases for the WCD, four real-life clinical cases are presented where patients received the device slightly outside the established guidelines. These cases demonstrate the broader utility of WCDs in situations involving acute myocarditis, thyrotoxicosis, pre-excited atrial fibrillation and awaiting staging/prognosis of a lung tumour. The findings prompt expansion of the existing guidelines for WCD use to efficiently protect more patients whose risk of arrhythmic cardiac death is transient or uncertain. This could be achieved by establishing a European register of the patients who receive a WCD for further analysis.

Long-term survival after cardiac arrest in patients undergoing emergent coronary angiography.

AIM: To determine long-term survival of patients after cardiac arrest undergoing emergent coronary angiography and therapeutic hypothermia. METHODS: We analysed data from patients treated within the regional STEMI Network from January 2015 to December 2020. The primary endpoint was all-cause mortality at median follow-up. Secondary endpoints were periprocedural complications (arrhythmias, pulmonary edema, cardiogenic shock, mechanical complication, stent thrombosis, reinfarction, bleeding) and 6-month all-cause death. A landmark analysis was performed, studying two time periods; 0-6 months and beyond 6 months. RESULTS: From a total of 24,125 patients in the regional STEMI network, 494 patients who suffered from cardiac arrest were included and divided into two groups: treated with (n = 119) and without therapeutic hypothermia (n = 375). At median follow-up (16.0 [0.2-33.3] months), there was no difference in the adjusted mortality rate between groups (51.3 % with hypothermia vs 48.0 % without hypothermia; HRadj1.08 95%CI [0.77-1.53]; p = 0.659). There was a higher frequency of bleeding in the hypothermia group (6.7 % vs 1.1 %; ORadj 7.99 95%CI [2.05-31.2]; p = 0.002), without difference for the rest of periprocedural complications. At 6-month follow-up, adjusted all-cause mortality rate was similar between groups (46.2 % with hypothermia vs 44.5 % without hypothermia; HRadj1.02 95%CI [0.71-1.47]; p = 0.900). Also, no differences were observed in the adjusted mortality rate between 6 months and median follow-up (9.4 % with hypothermia vs 6.3 % without hypothermia; HRadj2.02 95%CI [0.69-5.92]; p = 0.200). CONCLUSIONS: In a large cohort of patients with cardiac arrest within a regional STEMI network, those treated with therapeutic hypothermia did not improve long-term survival compared to those without hypothermia.

Coronary features across the spectrum of out-of-hospital cardiac arrest with ST-elevation myocardial infarction (CAD-OHCA study).

AIM: We hypothesized that adult patients with out-of-hospital cardiac arrest (OHCA) and ST-elevation myocardial infarction (STEMI) requiring prolonged resuscitation have more severe coronary artery disease (CAD) than those responding rapidly, and more severe CAD than patients with STEMI without OHCA. METHODS: Consecutive conscious and comatose OHCA patients with STEMI after reestablishment of spontaneous circulation (ROSC), and patients with refractory OHCA undergoing veno-arterial extracorporeal membrane oxygenation (E-CPR OHCA) were compared to STEMI without OHCA (STEMI no OHCA). CAD severity was assessed by a single physician blinded to the resuscitation method, time to ROSC and level of consciousness. RESULTS: Between 2016 and 2022, 71 conscious OHCA, 157 comatose OHCA, 50 E-CPR OHCA and 101 STEMI no OHCA underwent immediate coronary angiography. Acute culprit lesion was documented less often in OHCA (88.1% vs 97%; p = 0.009) but complete occlusion was more frequent (68.8% vs 58.4%; p = 0.038) than in STEMI no OHCA. SYNTAX score was 5.6 in STEMI no OHCA, 10.2 in conscious OHCA, 13.4 in comatose OHCA and 26.8 in E-CPR OHCA (p < 0.001). There was a linear correlation between SYNTAX score and delay to ROSC/ECMO initiation (r2 = 0.61; p < 0.001). Post PCI culprit TIMI 3 flow was comparable between the groups (≥86%). SYNTAX score was among independent predictors of 5-year survival which was significantly decreased in comatose OHCA (56.1%) and E-CPR OHCA (36.0%) compared to conscious OHCA (83.1%) and STEMI no OHCA (88.1%). CONCLUSION: Compared to STEMI no OHCA, OHCA was associated with increased incidence of acute coronary occlusion and more complex non culprit CAD which progressively increased from conscious OHCA to E-CPR OHCA. Severity of CAD was associated with increased delays to ROSC/ECMO initiation and decreased long term survival.

MIRACLE2 Score Compared With Downtime and Current Selection Criterion for Invasive Cardiovascular Therapies After OHCA.

BACKGROUND: The MIRACLE2 score is the only risk score that does not incorporate and can be used for selection of therapies after out-of-hospital cardiac arrest (OHCA). OBJECTIVES: This study sought to compare the discrimination performance of the MIRACLE2 score, downtime, and current randomized controlled trial (RCT) recruitment criteria in predicting poor neurologic outcome after out-of-hospital cardiac arrest (OHCA). METHODS: We used the EUCAR (European Cardiac Arrest Registry), a retrospective cohort from 6 centers (May 2012-September 2022). The primary outcome was poor neurologic outcome on hospital discharge (cerebral performance category 3-5). RESULTS: A total of 1,259 patients (total downtime = 25 minutes; IQR: 15-36 minutes) were included in the study. Poor outcome occurred in 41.8% with downtime <30 minutes and in 79.3% for those with downtime >30 minutes. In a multivariable logistic regression analysis, MIRACLE2 had a stronger association with outcome (OR: 2.23; 95% CI: 1.98-2.51; P < 0.0001) than zero flow (OR: 1.07; 95% CI: 1.01-1.13; P = 0.013), low flow (OR: 1.04; 95% CI: 0.99-1.09; P = 0.054), and total downtime (OR: 0.99; 95% CI: 0.95-1.03; P = 0.52). MIRACLE2 had substantially superior discrimination for the primary endpoint (AUC: 0.877; 95% CI: 0.854-0.897) than zero flow (AUC: 0.610; 95% CI: 0.577-0.642), low flow (AUC: 0.725; 95% CI: 0.695-0.754), and total downtime (AUC: 0.732; 95% CI: 0.701-0.760). For those modeled for exclusion from study recruitment, the positive predictive value of MIRACLE2 ≥5 for poor outcome was significantly higher (0.92) than the CULPRIT-SHOCK (Culprit lesion only PCI Versus Multivessel PCI in Cardiogenic Shock) (0.80), EUROSHOCK (Testing the value of Novel Strategy and Its Cost Efficacy In Order to Improve the Poor Outcomes in Cardiogenic Shock) (0.74) and ECLS-SHOCK (Extra-corporeal life support in Cardiogenic shock) criteria (0.81) (P < 0.001). CONCLUSIONS: The MIRACLE2 score has superior prediction of outcome after OHCA than downtime and higher discrimination of poor outcome than the current RCT recruitment criteria. The potential for the MIRACLE2 score to improve the selection of OHCA patients should be evaluated formally in future RCTs.

Predicting recurrent cardiac arrest in individuals surviving Out-of-Hospital cardiac arrest.

BACKGROUND: Despite improvements in short-term survival for Out-of-Hospital Cardiac Arrest (OHCA) in the past two decades, long-term survival is still not well studied. Furthermore, the contribution of different variables on long-term survival have not been fully investigated. AIM: Examine the 1-year prognosis of patients discharged from hospital after an OHCA. Furthermore, identify factors predicting re-arrest and/or death during 1-year follow-up. METHODS: All patients 18 years or older surviving an OHCA and discharged from the hospital were identified from the Swedish Register for Cardiopulmonary Resuscitation (SRCR). Data on diagnoses, medications and socioeconomic factors was gathered from other Swedish registers. A machine learning model was constructed with 886 variables and evaluated for its predictive capabilities. Variable importance was gathered from the model and new models with the most important variables were created. RESULTS: Out of the 5098 patients included, 902 (∼18%) suffered a recurrent cardiac arrest or death within a year. For the outcome death or re-arrest within 1 year from discharge the model achieved an ROC (receiver operating characteristics) AUC (area under the curve) of 0.73. A model with the 15 most important variables achieved an AUC of 0.69. CONCLUSIONS: Survivors of an OHCA have a high risk of suffering a re-arrest or death within 1 year from hospital discharge. A machine learning model with 15 different variables, among which age, socioeconomic factors and neurofunctional status at hospital discharge, achieved almost the same predictive capabilities with reasonable precision as the full model with 886 variables.

Clinical Features and Outcomes Among Patients With Refractory Out-of-Hospital Cardiac Arrest and an Initial Shockable Rhythm.

BACKGROUND: Clinical features among patients with refractory out-of-hospital cardiac arrest (OHCA) and initial shockable rhythms of ventricular fibrillation/pulseless ventricular tachycardia are not well-characterized. METHODS: We compared clinical characteristics and coronary angiographic findings between patients with refractory OHCA (incessant ventricular fibrillation/pulseless ventricular tachycardia after ≥3 direct-current shocks) and those without refractory OHCA. RESULTS: Between 2014 and 2018, a total of 204 patients with ventricular fibrillation/pulseless ventricular tachycardia OHCA (median age 62; males 78%) were divided into groups with (36%, 74/204) and without refractory arrest (64%, 130/204). Refractory OHCA patients had longer cardiopulmonary resuscitation (23 versus 15 minutes), more frequently required ≥450 mg amiodarone (34% versus 3.8%), and had cardiogenic shock (80% versus 55%) necessitating higher adrenaline dose (4.0 versus 1.0 mg) and higher rates of mechanical ventilation (92% versus 74%; all P<0.01). Of 167 patients (82%) selected for coronary angiography, 33% (n=55) had refractory OHCA (P=0.035). Significant coronary artery disease (≥1 major vessel with >70% stenosis) was present in >70% of patients. Refractory OHCA patients frequently had acute coronary occlusion (64% versus 47%), especially left circumflex (20% versus 6.4%) and graft vessel (7.3% versus 0.9%; all P<0.05) compared with those without refractory OHCA. Refractory OHCA group had higher in-hospital mortality (45% versus 30%, P=0.036) and greater new requirement for dialysis (18% versus 6.3%, P=0.011). After adjustment, refractory OHCA was associated with over 2-fold higher odds of in-hospital mortality (odds ratio, 2.28 [95% CI, 1.06-4.89]; P=0.034). CONCLUSIONS: Refractory ventricular fibrillation/pulseless ventricular tachycardia OHCA was associated with more intensive resuscitation, higher rates of acute coronary occlusion, and poorer in-hospital outcomes, underscoring the need for future studies in this extreme-risk subgroup.

Resuscitation Quality Improvement® (RQI®) HeartCode Complete® program improves chest compression rate in real world out-of hospital cardiac arrest patients.

BACKGROUND: The Resuscitation Quality Improvement® (RQI®) HeartCode Complete® program is designed to enhance cardiopulmonary resuscitation (CPR) training by using real-time feedback manikins. Our objective was to assess the quality of CPR, such as chest compression rate, depth, and fraction, performed on out-of-hospital cardiac arrest (OHCA) patients among paramedics trained with the RQI® program vs. paramedics who were not. METHODS AND RESULTS: Adult OHCA cases from 2021 were analyzed; 353 OHCA cases were classified into one of three groups: 1) 0 RQI®-trained paramedics, 2) 1 RQI®-trained paramedic, and 3) 2-3 RQI®-trained paramedics. We reported the median of the average compression rate, depth, and fraction, as well as percent of compressions that were between 100 to 120/minute and percent of compressions that were 2.0 to 2.4 inches deep. Kruskal-Wallis Tests were used to assess differences in these metrics across the three groups of paramedics. Of 353 cases, the median of the average compression rate/minute among crews with 0, 1, and 2-3 RQI®-trained paramedics was 130, 125, and 125, respectively (p = 0.0032). Median percent of compressions between 100 to 120 compressions/minute was 10.3%, 19.7%, and 20.1% among crews with 0, 1, and 2-3 RQI®-trained paramedics, respectively (p = 0.0010). Median of the average compression depth was 1.7 inches across all three groups (p = 0.4881). Median compression fraction was 86.4%, 84.6%, and 85.5% among crews with 0, 1, and 2-3 RQI®-trained paramedics, respectively (p = 0.6371). CONCLUSIONS: RQI® training was associated with statistically significant improvement in chest compression rate, but not improved chest compression depth or fraction in OHCA.