Increasing Cost-Effectiveness of AEDs using Algorithms to Optimise Location.

OBJECTIVES: Volunteer responder systems (VRSs) aim to decrease time to defibrillation by dispatching trained volunteers to automated external defibrillators (AEDs) and out-of-hospital cardiac arrest (OHCA) victims. AEDs are often underutilized due to poor placement. This study provides a cost-effectiveness analysis of adding AEDs at strategic locations to maximize quality-adjusted life years (QALYs). METHODS: We simulated combined volunteer, police, firefighter, and emergency medical service response scenarios to OHCAs, and applied our methods to a case study of Amsterdam, the Netherlands. We compared the competing strategies of placing additional AEDs, using steps of 40 extra AEDs (0, 40, …, 1480), in addition to the existing 369 AEDs. Incremental cost-effectiveness ratios (ICERs) were calculated for each increase in additional AEDs, from a societal perspective. The effect of AED connection and time to connection on survival to hospital admission and neurological outcome at discharge was estimated using logistic regression, using OHCA data from Amsterdam from 2006-2018. Other model inputs were obtained from literature. RESULTS: Purchasing up to 1120 additional AEDs (ICER €75,669/QALY) was cost-effective at a willingness-to-pay threshold of €80,000/QALY, when positioned strategically. Compared to current practice, adding 1120 AEDs resulted in a gain of 0.111 QALYs (95% CI 0.110-0.112) at an increased cost of €3792 per OHCA (95% CI €3778-€3807). Health benefits per AED diminished as more AEDs were added. CONCLUSIONS: Our study identified cost-effective strategies to position AEDs at strategic locations in a VRS. The case study findings advocate for a substantial increase in the number of AEDs in Amsterdam.

Pre-hospital care after return of spontaneous circulation: Are we achieving our targets?

Background: Early restoration of normal physiology when return of spontaneous circulation (ROSC) is obtained after an out-of-hospital cardiac arrest (OHCA) reduces the risk of developing post-cardiac arrest syndrome (PCAS). This study aims to investigate if (and to which extent) this can be achieved within the scope of practice of standard emergency medical services (EMS) crews. Methods: A prospective mixed-methods quantitative and qualitative cohort study was performed including adult patients with a non-traumatic OHCA presented to a university hospital emergency department (ED) in the Netherlands after pre-hospital ROSC was obtained. Primary endpoint was the percentage of patients with deranged physiology post-ROSC in whom EMS crews were able to reach recommended treatment targets. Results: During a 32-month period, 160 patients presenting with ROSC after OHCA were included. Median (IQR) pre-hospital treatment duration was 40 (34-51) minutes. When deranged physiology was present (n = 133), it could be restored by EMS crews in 29% of the patients. Although average etCO2 and SpO2 improved gradually over time during pre-hospital treatment, recommended treatment targets could not be achieved in respectively 55% (30/55) and 43% (20/46) of the patients. Similarly, airway problems (24/46, 52%), hypotension (20/23, 87%) and post-anoxic agitation (16/43, 37%) could often not be resolved by EMS crews. The ability to restore normal physiology by EMS could not be predicted based on patient characteristics or in-arrest variables. Conclusion: Deranged physiology after an OHCA is commonly encountered, and often difficult to treat within the scope of practice of regular EMS crews. Involvement of advanced critical care teams with a wider scope of practice at an early stage may contribute to a better outcome for these patients.

A Cross-Sectional Analysis of Bystander Cardiopulmonary Resuscitation (CPR): Behavioural Changes in the COVID-19 Era.

Objectives The coronavirus disease 2019 (COVID-19) pandemic has impacted public health systems and individuals' behaviour, with decreasing survival rates among out-of-hospital cardiac arrest (OHCA) patients. Bystander cardiopulmonary resuscitation (CPR) improves OHCA outcomes, which may have been affected by COVID-19. We sought to understand the impacts of COVID-19 on bystanders' willingness to administer CPR in three Canadian provinces. Methods Participants ≥ 18 years of age were surveyed online about their current and recalled pre-pandemic attitudes toward CPR and perceived transmission risk. We compared mean willingness to perform various CPR actions before and during the pandemic using paired t-tests. Differences in willingness across three provinces were assessed using analysis of variance (ANOVA) and Tukey's Honestly Significant Difference (HSD) test. We also conducted Chi-square tests to assess changes in willingness to perform CPR on children and older adults. Results Five hundred thirty-five participants were surveyed from October 1 to November 15, 2021. The mean age was 42.7 years (SD 14.5), and 60.2% were female. Participants reported less willingness to perform chest compressions on strangers during the pandemic compared to their recollections before the pandemic (mean willingness 86.2% vs. 94.3% prior, p<0.001). With personal protective equipment (PPE) available, particularly masks, willingness recovered to 91.3% (p<0.001). Willingness was higher in Nova Scotia (NS) than in British Columbia (BC) or Ontario (ON). Reluctance to assist older adults increased from 6.6% to 12.0% (p=0.020). Conclusions This study highlights changes in CPR willingness during the COVID-19 pandemic, underscoring the importance of PPE and offering insights into public health strategies pertaining to CPR during a pandemic.

Cardiopulmonary resuscitation at operating room entry in acute aortic dissection type A patients: is surgery contraindicated?

Background: This study aimed to compare the short-term outcomes of surgical treatment for acute type A aortic dissection between patients undergoing cardiopulmonary arrest at the time of entry into the operating room and patients who received successful preoperative cardiopulmonary resuscitation before entering the operating room or patients who had cardiopulmonary arrest on the operating room table after entering the operating room without cardiopulmonary arrest. In the present study, we focused on the circulatory status at the time of entering the operating room because it is economically and emotionally difficult to cease intervention once the patient has entered the operating room, where surgeons, anesthesiologists, nurses, and perfusionists are already present, all necessary materials are packed off and cardiopulmonary bypass have already been primed. Methods: Twenty (5.5%) of 362 patients who underwent surgical treatment for acute type A aortic dissection between January 2016 and March 2022 had preoperative cardiopulmonary arrest. To compare the early operative outcomes, the patients were divided into the spontaneous circulation group (n = 14, 70.0%) and the non-spontaneous circulation group (n = 6, 30.0%) based on the presence or absence of spontaneous circulation upon entering the operating room. The primary endpoint was postoperative 30-day mortality. The secondary endpoints included in-hospital complications and persistent neurological disorders. Results: Thirty-day mortality was 65% (n = 13/20) in the entire cohort; 50% (n = 7/14) in the spontaneous circulation group and 100% (n = 6/6) in the non-spontaneous circulation group. The major cardiopulmonary arrest causes were aortic rupture and cardiac tamponade (n = 16; 80.0%), followed by coronary malperfusion (n = 4; 20.0%). Seven patients (50.0%) survived in the spontaneous circulation group, and none survived in the non-spontaneous circulation group (P = .044). Five survivors walked unaided and were discharged home; the remaining two were comatose and paraplegic. Conclusions: The outcomes were extremely poor in patients with acute type A aortic dissection who had preoperative cardiopulmonary arrest and received ongoing cardiopulmonary resuscitation at entry into the operating room. Therefore, surgical treatment might be contraindicated in such patients.

Performance of the MRI lesion pattern score in predicting neurological outcome after out of hospital cardiac arrest: a retrospective cohort analysis.

BACKGROUND: Despite advances in resuscitation practice, patient survival following cardiac arrest remains poor. The utilization of MRI in neurological outcome prognostication post-cardiac arrest is growing and various classifications has been proposed; however a consensus has yet to be established. MRI, though valuable, is resource-intensive, time-consuming, costly, and not universally available. This study aims to validate a MRI lesion pattern score in a cohort of out of hospital cardiac arrest patients at a tertiary referral hospital in Switzerland. METHODS: This cohort study spanned twelve months from February 2021 to January 2022, encompassing all unconscious patients aged ≥ 18 years who experienced out-of-hospital cardiac arrest of any cause and were admitted to the intensive care unit (ICU) at Inselspital, University Hospital Bern, Switzerland. We included patients who underwent the neuroprognostication process, assessing the performance and validation of a MRI scoring system. RESULTS: Over the twelve-month period, 137 patients were admitted to the ICU, with 52 entering the neuroprognostication process and 47 undergoing MRI analysis. Among the 35 MRIs indicating severe hypoxic brain injury, 33 patients (94%) experienced an unfavourable outcome (UO), while ten (83%) of the twelve patients with no or minimal MRI lesions had a favourable outcome. This yielded a sensitivity of 0.94 and specificity of 0.83 for predicting UO with the proposed MRI scoring system. The positive and negative likelihood ratios were 5.53 and 0.07, respectively, resulting in an accuracy of 91.49%. CONCLUSION: We demonstrated the effectiveness of the MLP scoring scheme in predicting neurological outcome in patients following cardiac arrest. However, to ensure a comprehensive neuroprognostication, MRI results need to be combined with other assessments. While neuroimaging is a promising objective tool for neuroprognostication, given the absence of sedation-related confounders-compared to electroencephalogram (EEG) and clinical examination-the current lack of a validated scoring system necessitates further studies. Incorporating standardized MRI techniques and grading systems is crucial for advancing the reliability of neuroimaging for neuroprognostication. TRIAL REGISTRATION: Registry of all Projects in Switzerland (RAPS) 2020-01761.

International facets of the 'chain of survival' for out-of-hospital and in-hospital cardiac arrest - A scoping review.

Background: The "chain of survival" was first systematically addressed in 1991, and its sequence still forms the cornerstone of current resuscitation guidelines. The term "chain of survival" is widely used around the world in literature, education, and awareness campaigns, but growing heterogeneity in the components of the chain has led to confusion. It is unclear which of these emerging chains is most suitable, or if adaptations are needed in particular contexts to depict key actions of resuscitation in the 21st century. This scoping review provides an overview of the variety of chains of survival described. Objectives: To identify published facets of the chain of survival, to assess views and strategies about adapting the chain, and to identify reports on how the chain of survival affects teaching, implementation, or patient outcomes. Methods eligibility criteria and sources of evidence: A scoping review as part of the continuous evidence evaluation process of the International Liaison Committee on Resuscitation (ILCOR) was conducted. MEDLINE(R) ALL (Ovid), Embase (Ovid), APA PsycINFO (Ovid), CINAHL (Ebscohost), ERIC (Ebscohost), Web of Science (Clarivate), Scopus (Elsevier), and Cochrane Library (Wiley Online) were searched. All publications in all languages describing chains of survival were eligible, without time restrictions. Due to the heterogeneity and publication types of the relevant studies, we did not pursue a systematic review or meta-analysis. Results: A primary search yielded 1713 studies and after screening we included 43 publications. Modified versions of the chain of survival for specific contexts were found (e.g., in-hospital cardiac arrest or paediatric resuscitation). There were also numerous versions with minor adaptations of the existing chain. Three publications suggested an impact of the use of the chain of survival on patient outcomes. No educational or implementation outcomes were reported. Conclusion: There is a vast heterogeneity of chain of survival concepts published. Future research is warranted, especially into the concept's importance concerning educational, implementation, and clinical outcomes.

Emerging Evidence in Out-of-Hospital Cardiac Arrest-A Critical Appraisal of the Cardiac Arrest Center.

The morbidity and mortality of out-of-hospital cardiac arrest (OHCA) due to presumed cardiac causes have remained unwaveringly high over the last few decades. Less than 10% of patients survive until hospital discharge. Treatment of OHCA patients has traditionally relied on expert opinions. However, there is growing evidence on managing OHCA patients favorably during the prehospital phase, coronary and intensive care, and even beyond hospital discharge. To improve outcomes in OHCA, experts have proposed the establishment of cardiac arrest centers (CACs) as pivotal elements. CACs are expert facilities that pool resources and staff, provide infrastructure, treatment pathways, and networks to deliver comprehensive and guideline-recommended post-cardiac arrest care, as well as promote research. This review aims to address knowledge gaps in the 2020 consensus on CACs of major European medical associations, considering novel evidence on critical issues in both pre- and in-hospital OHCA management, such as the timing of coronary angiography and the use of extracorporeal cardiopulmonary resuscitation (eCPR). The goal is to harmonize new evidence with the concept of CACs.

Cerebrospinal Creatine Kinase BB Isoenzyme: A Biomarker for Predicting Outcome After Cardiac Arrest.

BACKGROUND: Cerebrospinal fluid creatine kinase BB isoenzyme (CSF CK-BB) after cardiac arrest (CA) has been shown to have a high positive predictive value for poor neurological outcome, but it has not been evaluated in the setting of targeted temperature management (TTM) and modern CA care. We aimed to evaluate CSF CK-BB as a prognostic biomarker after CA. METHODS: We performed a retrospective cohort study of patients with CA admitted between 2010 and 2020 to a three-hospital health system who remained comatose and had CSF CK-BB assayed between 36 and 84 h after CA. We examined the proportion of patients at hospital discharge who achieved favorable or intermediate neurological outcome, defined as Cerebral Performance Category score of 1-3, compared with those with poor outcome (Cerebral Performance Category score 4-5) for various CSF CK-BB thresholds. We also evaluated additive value of bilateral absence of somatosensory evoked potentials (SSEPs). RESULTS: Among 214 eligible patients, the mean age was 54.7 ± 4.8 years, 72% of patients were male, 33% were nonwhite, 17% had shockable rhythm, 90% were out-of-hospital CA, and 83% received TTM. A total of 19 (9%) awakened. CSF CK-BB ≥ 230 U/L predicted a poor outcome at hospital discharge, with a specificity of 100% (95% confidence interval [CI] 82-100%) and sensitivity of 69% (95% CI 62-76%). When combined with bilaterally absent N20 response on SSEP, specificity remained 100% while sensitivity increased to 80% (95% CI 73-85%). Discordant CK-BB and SSEP findings were seen in 13 (9%) patients. CONCLUSIONS: Cerebrospinal fluid creatine kinase BB isoenzyme levels accurately predicted poor neurological outcome among CA survivors treated with TTM. The CSF CK-BB cutoff of 230 U/L optimizes sensitivity to 69% while maintaining a specificity of 100%. CSF CK-BB could be a useful addition to multimodal neurological prognostication after CA.

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

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

Neuroprotective Effects of Inhaled Xenon Gas on Brain Structural Gray Matter Changes After Out-of-Hospital Cardiac Arrest Evaluated by Morphometric Analysis: A Substudy of the Randomized Xe-Hypotheca Trial.

BACKGROUND: We have earlier reported that inhaled xenon combined with hypothermia attenuates brain white matter injury in comatose survivors of out-of-hospital cardiac arrest (OHCA). A predefined secondary objective was to assess the effect of inhaled xenon on the structural changes in gray matter in comatose survivors after OHCA. METHODS: Patients were randomly assigned to receive either inhaled xenon combined with target temperature management (33 °C) for 24 h (n = 55, xenon group) or target temperature management alone (n = 55, control group). A change of brain gray matter volume was assessed with a voxel-based morphometry evaluation of high-resolution structural brain magnetic resonance imaging (MRI) data with Statistical Parametric Mapping. Patients were scheduled to undergo the first MRI between 36 and 52 h and a second MRI 10 days after OHCA. RESULTS: Of the 110 randomly assigned patients in the Xe-Hypotheca trial, 66 patients completed both MRI scans. After all imaging-based exclusions, 21 patients in the control group and 24 patients in the xenon group had both scan 1 and scan 2 available for analyses with scans that fulfilled the quality criteria. Compared with the xenon group, the control group had a significant decrease in brain gray matter volume in several clusters in the second scan compared with the first. In a between-group analysis, significant reductions were found in the right amygdala/entorhinal cortex (p = 0.025), left amygdala (p = 0.043), left middle temporal gyrus (p = 0.042), left inferior temporal gyrus (p = 0.008), left parahippocampal gyrus (p = 0.042), left temporal pole (p = 0.042), and left cerebellar cortex (p = 0.005). In the remaining gray matter areas, there were no significant changes between the groups. CONCLUSIONS: In comatose survivors of OHCA, inhaled xenon combined with targeted temperature management preserved gray matter better than hypothermia alone. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT00879892.

Successful prehospital ECMO in drowning resuscitation after prolonged submersion.

An 18-year-old drowning victim was successfully resuscitated using prehospital veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Despite 24 min of submersion in water with a surface temperature of 15 °C, the patient was cannulated on-scene and transported to a trauma center. After ICU admission on VA-ECMO, he was decannulated and extubated by day 5. He was transferred to a peripheral hospital on day 6 and discharged home after 3.5 weeks with favorable neurological outcome of a Cerebral Performance Categories (CPC) score of 1 out of 5. This case underscores the potential of prehospital ECMO in drowning cases within a well-equipped emergency response system.

Verification of the termination of resuscitation rules in pediatric out-of-hospital cardiac arrest cases.

Aim: Pediatric out-of-hospital cardiac arrest has an unfavorable prognosis; therefore, making accurate predictions of outcomes is crucial for tailoring treatment plans. The termination of resuscitation rules must accurately predict unfavorable outcomes. In this study, we aimed to assess if the current termination of resuscitation rules for adults can predict factors associated with unfavorable outcomes in pediatric out-of-hospital cardiac arrest and examine the relationship between these factors and unfavorable outcomes. Methods: A retrospective nationwide cohort study of pediatric cases registered in the Japanese Association for Acute Medicine Multicenter Out-of-Hospital Cardiac Arrest Registry from June 1, 2014, to December 31, 2020, was conducted. The association between the current termination of resuscitation rules and outcomes, such as 30-day mortality and unfavorable 30-day neurological outcomes following out-of-hospital cardiac arrest, was evaluated. Results: A total of 1,216 participants were included. The positive predictive value for predicting 30-day mortality for each termination of resuscitation rule exceeded 0.9. The specificity and positive predictive value for predicting unfavorable 30-day neurological outcomes were 1.00, indicating that no rules identified favorable outcomes. Factors such as no bystander witness, no return of spontaneous circulation before hospital arrival, no automated external defibrillator or defibrillator use, and no bystander cardiopulmonary resuscitation were associated with poor 30-day mortality and neurological outcomes. Conclusion: Adult termination of resuscitation rules had a high positive predictive value for predicting pediatric out-of-hospital cardiac arrest. However, surviving cases make it challenging to use these rules for end-of-resuscitation decisions, indicating the need for identifying new rules to help predict neurological outcomes.

Associated Factors of Patients' Survival in Out of Hospital Cardiac Arrest; a Cross-sectional Study.

Introduction: Chinese populations have an increasingly high prevalence of cardiac arrest. This study aimed to investigate the prehospital associated factors of survival to hospital admission and discharge among out-of-hospital cardiac arrest (OHCA) adult cases in Macao Special Administrative Region (SAR), China. Methods: Baseline characteristics as well as prehospital factors of OHCA patients were collected from publicly accessible medical records and Macao Fire Services Bureau, China. Demographic and other prehospital OHCA characteristics of patients who survived to hospital admission and discharge were analyzed using multivariate logistic regression analysis. Results: A total of 904 cases with a mean age of 74.2±17.3 (range: 18-106) years were included (78%>65 years, 62% male). Initial shockable cardiac rhythm was the strongest predictor for survival to both hospital admission (OR=3.57, 95% CI: 2.26-5.63; p<0.001) and discharge (OR=12.40, 95% CI: 5.70-26.96; p<0.001). Being male (OR=1.63, 95% CI:1.08-2.46; p =0.021) and the lower emergency medical service (EMS) response time (OR=1.62, 95% CI: 1.12-2.34; p =0.010) were also associated with a 2-fold association with survival to hospital admission. In addition, access to prehospital defibrillation (OR=4.25, 95% CI: 1.78-10.12; p <0.001) had a 4-fold association with survival to hospital discharge. None of these associations substantively increased with age. Conclusion: The major OHCA predictors of survival were initial shockable cardiac rhythm, being male, lower EMS response time, and access to prehospital defibrillation. These findings indicate a need for increased public awareness and more education.

Incidence, risk factors, and impact of post-return of spontaneous circulation events in patients with out-of-hospital cardiac arrest: a population-based study in Tokyo, Japan.

AIM: Patients with the return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest (OHCA) are unstable and often experience rearrest, after which ROSC may be reattained. This study investigated the incidence and risk factors of post-ROSC events (rearrest and subsequent reattainment of ROSC) and their impact on outcomes in patients with prehospital ROSC following OHCA. METHODS: Patients with OHCA and prehospital ROSC were identified from the Tokyo Fire Department database between 1 January 2018 and 31 December 2022. The factors associated with post-ROSC events and their impact on 1-month favourable neurological outcome (cerebral performance category scale: 1 or 2) were assessed using multivariable logistic regression analysis. RESULTS: Overall, 64,000 individuals experienced OHCA, and 6,190 (9.7%) had ROSC. Rearrest was confirmed in 28.4% of patients with ROSC, and was associated with age, time of emergency call, location of cardiac arrest, dispatcher instruction regarding cardiopulmonary resuscitation, first recorded cardiac rhythm, bystander cardiopulmonary resuscitation, defibrillation by a bystander, response time, and prehospital interventions. ROSC reattainment was confirmed in 34.5% of patients with rearrest and associated with the first recorded cardiac rhythm and defibrillation by a bystander. Patients without rearrests had the highest proportion of favourable neurological outcomes, followed by those with solved and unsolved rearrests (38.6% vs. 22.4% and 4.4%, P <0.001). The difference remained significant after adjustment for confounders. CONCLUSION: This study revealed population-based incidence and risk factors of post-ROSC events. Rearrest was common, leading to unfavourable neurological outcome; however, its deleterious impact may be mitigated by successful resuscitation efforts.

Influence of Cooling duration on Efficacy in Cardiac Arrest Patients (ICECAP): study protocol for a multicenter, randomized, adaptive allocation clinical trial to identify the optimal duration of induced hypothermia for neuroprotection in comatose, adult survivors of after out-of-hospital cardiac arrest.

Background: Cardiac arrest is a common and devastating emergency of both the heart and brain. More than 380,000 patients suffer out-of-hospital cardiac arrest annually in the United States. Induced cooling of comatose patients markedly improved neurological and functional outcomes in pivotal randomized clinical trials, but the optimal duration of therapeutic hypothermia has not yet been established. Methods: This study is a multi-center randomized, response-adaptive, duration (dose) finding, comparative effectiveness clinical trial with blinded outcome assessment. We investigate two populations of adult comatose survivors of cardiac arrest to ascertain the shortest duration of cooling that provides the maximum treatment effect. The design is based on a statistical model of response as defined by the primary endpoint, a weighted 90-day mRS (modified Rankin Scale, a measure of neurologic disability), across the treatment arms. Subjects will initially be equally randomized between 12, 24, and 48 hours of therapeutic cooling. After the first 200 subjects have been randomized, additional treatment arms between 12 and 48 hours will be opened and patients will be allocated, within each initial cardiac rhythm type (shockable or non-shockable), by response adaptive randomization. As the trial continues, shorter and longer duration arms may be opened. A maximum sample size of 1800 subjects is proposed. Secondary objectives are to characterize: the overall safety and adverse events associated with duration of cooling, the effect on neuropsychological outcomes, and the effect on patient reported quality of life measures. Discussion: In-vitro and in-vivo studies have shown the neuroprotective effects of therapeutic hypothermia for cardiac arrest. We hypothesize that longer durations of cooling may improve either the proportion of patients that attain a good neurological recovery or may result in better recovery among the proportion already categorized as having a good outcome. If the treatment effect of cooling is increasing across duration, for at least some set of durations, then this provides evidence of the efficacy of cooling itself versus normothermia, even in the absence of a normothermia control arm, confirming previous RCTs for OHCA survivors of shockable rhythms and provides the first prospective controlled evidence of efficacy in those without initial shockable rhythms. Trial registration: ClinicalTrials.gov (NCT04217551, 2019-12-30).

Caregiver strain among relatives of out-of-hospital cardiac arrest survivors; the DANCAS relative survey.

BACKGROUND: Knowledge about caregiver strain among relatives of out-of-hospital cardiac arrest (OHCA) survivors is limited. Thus, the objectives were to i) describe differences in self-reported mental well-being, mental health, and caregiver strain at different time points (1-5 years) post-OHCA and ii) investigate characteristics associated with caregiver strain. METHODS: A national cross-sectional survey (DANCAS) from October 2020 to March 2021 with OHCA survivors and their closest relatives. The relative survey included the WHO-5 Well-being Index (WHO-5), the Hospital Anxiety and Depression Scale (HADS) and the Modified Caregiver Strain Index (M-CSI). Differences in scores between time groups were explored using descriptive statistics. Associations between characteristics and caregiver strain were investigated with multivariable logistic regression models, presented as odds ratios (OR) with 95% confidence intervals (CI), adjusted for gender, age, education status, relative affiliation, and time after OHCA. RESULTS: Of 561 relatives, 24% (n = 137) experienced caregiver strain, with no significant differences in the relatives' mental well-being, mental health, or caregiver strain with time since OHCA. In the adjusted analyses, older age (OR 0.98 95% CI 0.96;0.99) and several self-reported outcomes, including reduced mental well-being (WHO-5 OR 7.27 95% CI 4.86;11.52), symptoms of anxiety (HADS-A OR 6.01 95% CI 3.89;9.29) and depression (HADS-D OR 15.03 95% CI 7.33;30.80) were significantly associated with worse caregiver strain. CONCLUSION: Nearly one-quarter of relatives of OHCA survivors experience caregiver strain, with this proportion remaining unchanged with time. Several outcomes were associated with caregiver strain, emphasising the need to identify relatives at greater risk of burden following OHCA.

Extracorporeal cardiopulmonary resuscitation versus standard treatment for refractory out-of-hospital cardiac arrest: a Bayesian meta-analysis.

BACKGROUND: The outcomes of several randomized trials on extracorporeal cardiopulmonary resuscitation (ECPR) in patients with refractory out-of-hospital cardiac arrest were examined using frequentist methods, resulting in a dichotomous interpretation of results based on p-values rather than in the probability of clinically relevant treatment effects. To determine such a probability of a clinically relevant ECPR-based treatment effect on neurological outcomes, the authors of these trials performed a Bayesian meta-analysis of the totality of randomized ECPR evidence. METHODS: A systematic search was applied to three electronic databases. Randomized trials that compared ECPR-based treatment with conventional CPR for refractory out-of-hospital cardiac arrest were included. The study was preregistered in INPLASY (INPLASY2023120060). The primary Bayesian hierarchical meta-analysis estimated the difference in 6-month neurologically favorable survival in patients with all rhythms, and a secondary analysis assessed this difference in patients with shockable rhythms (Bayesian hierarchical random-effects model). Primary Bayesian analyses were performed under vague priors. Outcomes were formulated as estimated median relative risks, mean absolute risk differences, and numbers needed to treat with corresponding 95% credible intervals (CrIs). The posterior probabilities of various clinically relevant absolute risk difference thresholds were estimated. RESULTS: Three randomized trials were included in the analysis (ECPR, n = 209 patients; conventional CPR, n = 211 patients). The estimated median relative risk of ECPR for 6-month neurologically favorable survival was 1.47 (95%CrI 0.73-3.32) with a mean absolute risk difference of 8.7% (- 5.0; 42.7%) in patients with all rhythms, and the median relative risk was 1.54 (95%CrI 0.79-3.71) with a mean absolute risk difference of 10.8% (95%CrI - 4.2; 73.9%) in patients with shockable rhythms. The posterior probabilities of an absolute risk difference > 0% and > 5% were 91.0% and 71.1% in patients with all rhythms and 92.4% and 75.8% in patients with shockable rhythms, respectively. CONCLUSION: The current Bayesian meta-analysis found a 71.1% and 75.8% posterior probability of a clinically relevant ECPR-based treatment effect on 6-month neurologically favorable survival in patients with all rhythms and shockable rhythms. These results must be interpreted within the context of the reported credible intervals and varying designs of the randomized trials. REGISTRATION: INPLASY (INPLASY2023120060, December 14th, 2023, https://doi.org/10.37766/inplasy2023.12.0060 ).

Out-of-hospital cardiac arrest research progress and challenges in Lithuania.

Aim: To present the evolution of data collection and analysis methods of out-of-hospital cardiac arrest (OHCA) research in Kaunas city, Lithuania, and discuss the challenges encountered. Methods: In late 2016, data collection began with a focus on 2016 data, following the Utstein 2014 template. The Kaunas city emergency medical services (EMS) station, which has a protocol dispatch system, pioneered the use of electronic submissions for the national EMS data collection form, making the research process more efficient. Most OHCA patients were treated in a tertiary university hospital which transitioned to electronic health record system in 2017, improving data accessibility. Throughout data collection significant efforts have been directed towards enhancing process efficiency and simplifying operations. As a result, the expansion of the Excel data table led to the creation of the ''resuscitation registry form' 'in 2018, which became operational in 2020. Results: The collected data were used in several observational studies to identify and better outcomes. Conclusion: Engaging in research on OHCA is difficult and poses many unique challenges owning to the urgency of the condition, complexity of legal and ethical considerations, and implications of any research intervention. The lack of a connection between the EMS and hospital electronic health record systems poses challenges for data collection. Legal and ethical complexities, including mandatory initiation of resuscitation and challenges in obtaining ethical approval, highlight the need for a comprehensive framework. This study aims transition the accumulated expertise into a nationally recognised registry for OHCA.

Health-related quality of life one year after refractory cardiac arrest treated with conventional or extracorporeal CPR; a secondary analysis of the INCEPTION-trial.

Background: Prospective, trial-based data comparing health-related quality of life (HRQoL) in patients surviving out-of-hospital cardiac arrest (OHCA) through extracorporeal cardiopulmonary resuscitation (ECPR) or conventional CPR (CCPR) are scarce. We aimed to determine HRQoL during 1-year after refractory OHCA in patients treated with ECPR and CCPR. Methods: We present a secondary analysis of the multicenter INCEPTION-trial, which studied the effectiveness of ECPR versus CCPR in patients with refractory OHCA. HRQoL was prospectively assessed using the EQ-5D-5L questionnaire. Poor HRQoL was pragmatically defined as an EQ-5D-5L health utility index (HUI) > 1 SD below the age-adjusted norm. We used mixed linear models to assess the difference in HRQoL over time and univariable analyses to assess factors potentially associated with poor HRQoL. Results: A total of 134 patients were enrolled, and hospital survival was 20% (27 patients). EQ-5D-5L data were available for 25 patients (5 ECPR and 20 CCPR). One year after OHCA, the estimated mean HUI was 0.73 (0.05) in all patients, 0.84 (0.12) in ECPR survivors, and 0.71 (0.05) in CCPR survivors (p-value 0.31). Eight (32%) survivors had a poor HRQoL. HRQoL was good in 17 (68%) patients, with 100% in ECPR survivors versus 60% in CCPR survivors (p-value 0.14). Conclusion: One year after refractory OHCA, 68% of the survivors had a good HRQoL. We found no statistically significant difference in HRQoL one year after OHCA in patients treated with ECPR compared to CCPR. However, numerical differences may be clinically relevant in favor of ECPR.

Long-term survival following out-of-hospital cardiac arrest in women and men: Influence of comorbidities, social characteristics, and resuscitation characteristics.

AIM: We aimed to study sex differences in long-term survival following out-of-hospital cardiac arrest (OHCA) compared to the general population, and determined associations for comorbidities, social characteristics, and resuscitation characteristics with survival in women and men separately. METHODS: We followed 2,452 Danish (530 women and 1,922 men) and 1,255 Dutch (259 women and 996 men) individuals aged ≥25 years, who survived 30 days post-OHCA in 2009-2015, until 2019. Using Poisson regression analyses we assessed sex differences in long-term survival and sex-specific associations of characteristics mutually adjusted, and compared survival with an age- and sex-matched general population. The potential predictive value was assessed with the Concordance-index. RESULTS: Post-OHCA survival was longer in women than men (adjusted incidence rate ratio (IRR) for mortality 0.74, 95%CI 0.61-0.89 in Denmark; 0.86, 95%CI 0.65-1.15 in the Netherlands). Both sexes had a shorter survival than the general population (e.g., IRR for mortality 3.07, 95%CI 2.55-3.70 and IRR 2.15, 95%CI 1.95-2.37 in Danish women and men). Higher age, glucose lowering medication, no dyslipidaemia medication, unemployment, and a non-shockable initial rhythm were associated with shorter survival in both sexes. Cardiovascular medication, depression/anxiety medication, living alone, low household income, and residential OHCA location were associated with shorter survival in men. Not living with children and bystander cardiopulmonary resuscitation provision were associated with shorter survival in women. The Concordance-indexes ranged from 0.51 to 0.63. CONCLUSIONS: Women survived longer than men post-OHCA. Several characteristics were associated with long-term post-OHCA survival, with some sex-specific characteristics. In both sexes, these characteristics had low predictive potential.