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.

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 ).

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.

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.

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.

Out-of-hospital paramedic interactions with people living with dementia: a scoping review.

BACKGROUND: Dementia encompasses neurodegenerative disorders that account for a global estimated healthcare expenditure of 1.3 trillion US dollars. In Australia, one in 12 people aged ≥65 has a diagnosis of dementia and it is the second leading cause of death. Paramedics play a crucial role in person-centred dementia care, particularly in the community. While consensus has been established on paramedicine's integration into interdisciplinary care teams, there remains a lack of clarity regarding the paramedic role in dementia care. OBJECTIVE: This study aimed to examine and report paramedic interactions with people living with dementia in the out-of-hospital setting. DESIGN AND SETTING: This was a scoping review study of paramedics and people living with dementia within the out-of-hospital setting. METHODS: This study was guided by the Joanna Briggs Institute (JBI) scoping review framework. Databases were searched without date limits, up to 4 April 2023. These encompassed OVID Medline, CINAHL, Scopus, APA PsycInfo and OVID Embase. Articles were included if they were primary, peer-reviewed studies in English and reporting on paramedic-specific interactions with people living with dementia in the out-of-hospital setting. Data extraction was performed based on study setting, design, population and key findings. RESULTS: Twenty-nine articles were included in the thematic analysis. Four themes emerged: need for training, patterns of attendances, patterns of documentation and the integrative potential of paramedicine. Paramedics reported feeling ill-equipped and unprepared in caring for patients living with dementia due to challenges in assessment and management of caregiver tensions. They were often called as a last resort due to poor service integration and a lack of alternative care pathways. Despite high conveyance rates, there was low incidence of paramedic interventions initiated. Underdocumentation of dementia and pain was found. CONCLUSION: Emergency ambulance conveyance of people living with dementia is a surface reaction compounded by a lack of direction for paramedics in the provision of out-of-hospital care. There is a pressing need for establishment of research and educational priorities to improve paramedic training in dementia-specific skillsets.

Outcomes in patients with out-of-hospital cardiac arrest according to prehospital advanced airway management timing: a retrospective observational study.

Background: In patients with out-of-hospital cardiac arrest (OHCA), guidelines recommend advanced airway (AA) management at the advanced cardiovascular life support stage; however, the ideal timing remains controversial. Therefore, we evaluated the prognosis according to the timing of AA in patients with OHCA. Methods: We conducted a retrospective observational study of patients with OHCA at six major hospitals in Daegu Metropolitan City, South Korea, from August 2019 to June 2022. We compared groups with early and late AA and evaluated prognosis, including recovery of spontaneous circulation (ROSC), survival to discharge, and neurological evaluation, according to AA timing. Results: Of 2,087 patients with OHCA, 945 underwent early AA management and 1,142 underwent late AA management. The timing of AA management did not influence ROSC in the emergency department (5-6 minutes: adjusted odds ratio [aOR], 0.97; p=0.914; 7-9 minutes: aOR, 1.37; p=0.223; ≥10 minutes: aOR, 1.32; p=0.345). The timing of AA management also did not influence survival to discharge (5-6 minutes: aOR, 0.79; p=0.680; 7-9 minutes: aOR, 1.04; p=0.944; ≥10 minutes: aOR, 1.86; p=0.320) or good neurological outcomes (5-6 minutes: aOR, 1.72; p=0.512; 7-9 minutes: aOR, 0.48; p=0.471; ≥10 minutes: aOR, 0.96; p=0.892). Conclusion: AA timing in patients with OHCA was not associated with ROSC, survival to hospital discharge, or neurological outcomes.

Days Alive and Out of Hospital as an Outcome Measure in Patients Receiving Hyperacute Stroke Intervention.

BACKGROUND: Patient outcome after stroke is frequently assessed with clinical scales such as the modified Rankin Scale score (mRS). Days alive and out of hospital at 90 days (DAOH-90), which measures survival, time spent in hospital or rehabilitation settings, readmission and institutionalization, is an objective outcome measure that can be obtained from large administrative data sets without the need for patient contact. We aimed to assess the comparability of DAOH with mRS and its relationship with other prognostic variables after acute stroke reperfusion therapy. METHODS AND RESULTS: Consecutive patients with ischemic stroke treated with intravenous thrombolysis or endovascular thrombectomy were analyzed. DAOH-90 was calculated from a national minimum data set, a mandatory nationwide administrative database. mRS score at day 90 (mRS-90) was assessed with in-person or telephone interviews. The study included 1278 patients with ischemic stroke (714 male, median age 70 [59-79], median National Institutes of Health Stroke Scale score 14 [9-20]). Median DAOH-90 was 71 [29-84] and median mRS-90 score was 3 [2-5]. DAOH-90 was correlated with admission National Institutes of Health Stroke Scale score (Spearman rho -0.44, P<0.001) and Alberta Stroke Program Early CT [Computed Tomography] Score (Spearman rho 0.24, P<0.001). There was a strong association between mRS-90 and DAOH-90 (Spearman rho correlation -0.79, P<0.001). Area under receiver operating curve for predicting mRS score >0 was 0.86 (95% CI, 0.84-0.88), mRS score >1 was 0.88 (95% CI, 0.86-0.90) and mRS score >2 was 0.90 (95% CI, 0.89-0.92). CONCLUSIONS: In patients with stroke treated with reperfusion therapies, DAOH-90 shows reasonable comparability to the more established outcome measure of mRS-90. DAOH-90 can be readily obtained from administrative databases and therefore has the potential to be used in large-scale clinical trials and comparative effectiveness studies.

The association of non-prescription drug use preceding out-of-hospital cardiac arrest and clinical outcomes.

BACKGROUND: Clinicians may make prognostication decisions for out-of-hospital cardiac arrest (OHCA) using historical details pertaining to non-prescription drug use. However, differences in outcomes between OHCAs with evidence of non-prescription drug use, compared to other OHCAs, have not been well described. METHODS: We included emergency medical service-treated OHCA in the British Columbia Cardiac Arrest Registry (January/2019-June/2023). We classified cases as "non-prescription drug-associated cardiac arrests" (DA-OHCA) if there was evidence of non-prescription drug use preceding the OHCA, including witness accounts of use within 24 hours or paraphernalia at the scene. We fit logistic regression models to investigate the association between DA-OHCA (vs. other cases) and favourable neurological outcome (Cerebral Performance Category [CPC] 1-2) and survival at hospital discharge, and return of spontaneous circulation (ROSC). RESULTS: Of 34,745 OHCA, 2,171 (12%) were classified as DA-OHCA. DA-OHCA tended to be younger, unwitnessed, occur during the evening or night, and present with a non-shockable rhythm, compared to other OHCA. DA-OHCA (221 [10%]) had a greater proportion (difference 1.8%; 95%CI 0.49-3.2) with favourable neurological outcomes compared to other OHCA (1,365 [8.4%]). Adjusted models did not identify an association of DA-OHCA with favourable neurological outcome (OR 1.08, 95%CI 0.87-1.33) or survival to hospital discharge (OR 1.13, 95%CI 0.93-1.38), but did demonstrate an association with ROSC (OR 1.13, 95%CI 1.004-1.27). CONCLUSION: In unadjusted models, DA-OHCA was associated with an improved odds of survival and favourable neurological outcomes at hospital discharge, compared to other OHCA. However, we did not detect these associations in adjusted analyses.

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.

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.

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 USA. 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 h of therapeutic cooling. After the first 200 subjects have been randomized, additional treatment arms between 12 and 48 h 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. Registered on 30 December 2019.

Cardiac arrest and cardiopulmonary resuscitation outcome reports: 2024 update of the Utstein Out-of-Hospital Cardiac Arrest Registry template.

The Utstein Out-of-Hospital Cardiac Arrest Resuscitation Registry Template, introduced in 1991 and updated in 2004 and 2015, standardizes data collection to enable research, evaluation, and comparisons of systems of care. The impetus for the current update stemmed from significant advances in the field and insights from registry development and regional comparisons. This 2024 update involved representatives of the International Liaison Committee on Resuscitation and used a modified Delphi process. Every 2015 Utstein data element was reviewed for relevance, priority (core or supplemental), and improvement. New variables were proposed and refined. All changes were voted on for inclusion. The 2015 domains-system, dispatch, patient, process, and outcomes-were retained. Further clarity is provided for the definitions of out-of-hospital cardiac arrest attended resuscitation and attempted resuscitation. Changes reflect advancements in dispatch, early response systems, and resuscitation care, as well as the importance of prehospital outcomes. Time intervals such as emergency medical service response time now emphasize precise reporting of the times used. New flowcharts aid the reporting of system effectiveness for patients with an attempted resuscitation and system efficacy for the Utstein comparator group. Recognizing the varying capacities of emergency systems globally, the writing group provided a minimal dataset for settings with developing emergency medical systems. Supplementary variables are considered useful for research purposes. These revisions aim to elevate data collection and reporting transparency by registries and researchers and to advance international comparisons and collaborations. The overarching objective remains the improvement of outcomes for patients with out-of-hospital cardiac arrest.