Race and Sex Differences in the Association of Bystander CPR for Cardiac Arrest.

BACKGROUND: Bystander cardiopulmonary resuscitation (CPR) is associated with higher survival for out-of-hospital cardiac arrest, but whether its association with survival differs by patients' sex and race and ethnicity is less clear. METHODS: Within a large US registry, we identified 623 342 nontraumatic out-of-hospital cardiac arrests during 2013 to 2022 for this observational cohort study. Using hierarchical logistic regression, we examined whether there was a differential association between bystander CPR and survival outcomes by patients' sex and race and ethnicity, overall and by neighborhood strata. RESULTS: Mean age was 62.1±17.1 years, and 35.9% were women. Nearly half of patients (49.8%) were non-Hispanic White; 20.6% were non-Hispanic Black; 7.3% were Hispanic; 2.9% were Asian; and 0.4% were Native American. Overall, 58 098 (9.3%) survived to hospital discharge. Although bystander CPR was associated with higher survival in each race and ethnicity group, the association of bystander CPR compared with patients without bystander CPR in each racial and ethnic group was highest in individuals who were White (adjusted odds ratio [OR], 1.33 [95% CI, 1.30-1.37]) and Native American (adjusted OR, 1.40 [95% CI, 1.02-1.90]) and lowest in individuals who were Black (adjusted OR, 1.09 [95% CI, 1.04-1.14]; Pinteraction<0.001). The adjusted OR for bystander CPR compared with those without bystander CPR for Hispanic patients was 1.29 (95% CI, 1.20-1.139), for Asian patients, it was 1.27 (95% CI, 1.12-1.42), and for those of unknown race, it was 1.31 (95% CI, 1.25-1.36). Similarly, bystander CPR was associated with higher survival in both sexes, but its association with survival was higher in men (adjusted OR, 1.35 [95% CI, 1.31-1.38]) than women (adjusted OR, 1.15 [95% CI, 1.12-1.19]; Pinteraction<0.001). The weaker association of bystander CPR in Black individuals and women was consistent across neighborhood race and ethnicity and income strata. Similar results were observed for the outcome of survival without severe neurological deficits. CONCLUSIONS: Although bystander CPR was associated with higher survival in all patients, its association with survival was weakest for Black individuals and women with out-of-hospital cardiac arrest.

Associations Between End-Tidal Carbon Dioxide During Pediatric Cardiopulmonary Resuscitation, Cardiopulmonary Resuscitation Quality, and Survival.

BACKGROUND: Supported by laboratory and clinical investigations of adult cardiopulmonary arrest, resuscitation guidelines recommend monitoring end-tidal carbon dioxide (ETCO2) as an indicator of cardiopulmonary resuscitation (CPR) quality, but they note that "specific values to guide therapy have not been established in children." METHODS: This prospective observational cohort study was a National Heart, Lung, and Blood Institute-funded ancillary study of children in the ICU-RESUS trial (Intensive Care Unit-Resuscitation Project; NCT02837497). Hospitalized children (≤18 years of age and ≥37 weeks postgestational age) who received chest compressions of any duration for cardiopulmonary arrest, had an endotracheal or tracheostomy tube at the start of CPR, and evaluable intra-arrest ETCO2 data were included. The primary exposure was event-level average ETCO2 during the first 10 minutes of CPR (dichotomized as ≥20 mm Hg versus <20 mm Hg on the basis of adult literature). The primary outcome was survival to hospital discharge. Secondary outcomes were sustained return of spontaneous circulation, survival to discharge with favorable neurological outcome, and new morbidity among survivors. Poisson regression measured associations between ETCO2 and outcomes as well as the association between ETCO2 and other CPR characteristics: (1) invasively measured systolic and diastolic blood pressures, and (2) CPR quality and chest compression mechanics metrics (ie, time to CPR start; chest compression rate, depth, and fraction; ventilation rate). RESULTS: Among 234 included patients, 133 (57%) had an event-level average ETCO2 ≥20 mm Hg. After controlling for a priori covariates, average ETCO2 ≥20 mm Hg was associated with a higher incidence of survival to hospital discharge (86/133 [65%] versus 48/101 [48%]; adjusted relative risk, 1.33 [95% CI, 1.04-1.69]; P=0.023) and return of spontaneous circulation (95/133 [71%] versus 59/101 [58%]; adjusted relative risk, 1.22 [95% CI, 1.00-1.49]; P=0.046) compared with lower values. ETCO2 ≥20 mm Hg was not associated with survival with favorable neurological outcome or new morbidity among survivors. Average 2 ≥20 mm Hg was associated with higher systolic and diastolic blood pressures during CPR, lower CPR ventilation rates, and briefer pre-CPR arrest durations compared with lower values. Chest compression rate, depth, and fraction did not differ between ETCO2 groups. CONCLUSIONS: In this multicenter study of children with in-hospital cardiopulmonary arrest, ETCO2 ≥20 mm Hg was associated with better outcomes and higher intra-arrest blood pressures, but not with chest compression quality metrics.

Improving Outcomes After Post-Cardiac Arrest Brain Injury: A Scientific Statement From the International Liaison Committee on Resuscitation.

This scientific statement presents a conceptual framework for the pathophysiology of post-cardiac arrest brain injury, explores reasons for previous failure to translate preclinical data to clinical practice, and outlines potential paths forward. Post-cardiac arrest brain injury is characterized by 4 distinct but overlapping phases: ischemic depolarization, reperfusion repolarization, dysregulation, and recovery and repair. Previous research has been challenging because of the limitations of laboratory models; heterogeneity in the patient populations enrolled; overoptimistic estimation of treatment effects leading to suboptimal sample sizes; timing and route of intervention delivery; limited or absent evidence that the intervention has engaged the mechanistic target; and heterogeneity in postresuscitation care, prognostication, and withdrawal of life-sustaining treatments. Future trials must tailor their interventions to the subset of patients most likely to benefit and deliver this intervention at the appropriate time, through the appropriate route, and at the appropriate dose. The complexity of post-cardiac arrest brain injury suggests that monotherapies are unlikely to be as successful as multimodal neuroprotective therapies. Biomarkers should be developed to identify patients with the targeted mechanism of injury, to quantify its severity, and to measure the response to therapy. Studies need to be adequately powered to detect effect sizes that are realistic and meaningful to patients, their families, and clinicians. Study designs should be optimized to accelerate the evaluation of the most promising interventions. Multidisciplinary and international collaboration will be essential to realize the goal of developing effective therapies for post-cardiac arrest brain injury.

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.

International Initiatives of the American Heart Association: Original Concepts, Present Programs, and Future Focus: A Science Advisory From the American Heart Association.

The American Heart Association (AHA), founded in 1924, is anchored in the core belief that scientific research can lead the way to better prevention, treatment, recovery, and ultimately a cure for cardiovascular disease. Historically, the association's involvement in international efforts centered on scientific cooperation. Activities mostly involved AHA leadership presenting at international scientific meetings and leaders from other countries sharing scientific and medical information at AHA meetings. Although the AHA's and American Stroke Association's international efforts have expanded substantially since those early days, global knowledge exchange remains the bedrock of its international endeavors. As the AHA turns 100, we reflect on the successful global efforts in prevention, resuscitation, global advocacy, quality improvement, and health equity that have guided the organization to a place of readiness for "advancing health and hope, for everyone, everywhere." Motivated by the enormous potential for population health gains in an aging world, the AHA is entering its second century with redoubled commitment to improving global cardiovascular and cerebrovascular health for all.

Cardiac Catheterization Laboratory Management of the Comatose Adult Patient With an Out-of-Hospital Cardiac Arrest: A Scientific Statement From the American Heart Association.

Out-of-hospital cardiac arrest is a leading cause of death, accounting for ≈50% of all cardiovascular deaths. The prognosis of such individuals is poor, with <10% surviving to hospital discharge. Survival with a favorable neurologic outcome is highest among individuals who present with a witnessed shockable rhythm, received bystander cardiopulmonary resuscitation, achieve return of spontaneous circulation within 15 minutes of arrest, and have evidence of ST-segment elevation on initial ECG after return of spontaneous circulation. The cardiac catheterization laboratory plays an important role in the coordinated Chain of Survival for patients with out-of-hospital cardiac arrest. The catheterization laboratory can be used to provide diagnostic, therapeutic, and resuscitative support after sudden cardiac arrest from many different cardiac causes, but it has a unique importance in the treatment of cardiac arrest resulting from underlying coronary artery disease. Over the past few years, numerous trials have clarified the role of the cardiac catheterization laboratory in the management of resuscitated patients or those with ongoing cardiac arrest. This scientific statement provides an update on the contemporary approach to managing resuscitated patients or those with ongoing cardiac arrest.

Recurrence of ventricular fibrillation in out-of-hospital cardiac arrest: Clinical evidence and underlying ionic mechanisms.

Defibrillation remains the optimal therapy for terminating ventricular fibrillation (VF) in out-of-hospital cardiac arrest (OHCA) patients, with reported shock success rates of ∼90%. A key persistent challenge, however, is the high rate of VF recurrence (∼50-80%) seen during post-shock cardiopulmonary resuscitation (CPR). Studies have shown that the incidence and time spent in recurrent VF are negatively associated with neurologically-intact survival. Recurrent VF also results in the administration of extra shocks at escalating energy levels, which can cause cardiac dysfunction. Unfortunately, the mechanisms underlying recurrent VF remain poorly understood. In particular, the role of chest-compressions (CC) administered during CPR in mediating recurrent VF remains controversial. In this review, we first summarize the available clinical evidence for refibrillation occurring during CPR in OHCA patients, including the postulated contribution of CC and non-CC related pathways. Next, we examine experimental studies highlighting how CC can re-induce VF via direct mechano-electric feedback. We postulate the ionic mechanisms involved by comparison with similar phenomena seen in commotio cordis. Subsequently, the hypothesized contribution of partial cardiac reperfusion (either as a result of CC or CC independent organized rhythm) in re-initiating VF in a globally ischaemic heart is examined. An overview of the proposed ionic mechanisms contributing to VF recurrence in OHCA during CPR from a cellular level to the whole heart is outlined. Possible therapeutic implications of the proposed mechanistic theories for VF recurrence in OHCA are briefly discussed.

Blood Pressure and Oxygen Targets on Kidney Injury After Cardiac Arrest.

BACKGROUND: Acute kidney injury (AKI) represents a common and serious complication to out-of-hospital cardiac arrest. The importance of post-resuscitation care targets for blood pressure and oxygenation for the development of AKI is unknown. METHODS: This is a substudy of a randomized 2-by-2 factorial trial, in which 789 comatose adult patients who had out-of-hospital cardiac arrest with presumed cardiac cause and sustained return of spontaneous circulation were randomly assigned to a target mean arterial blood pressure of either 63 or 77 mm Hg. Patients were simultaneously randomly assigned to either a restrictive oxygen target of a partial pressure of arterial oxygen (Pao2) of 9 to 10 kPa or a liberal oxygenation target of a Pao2 of 13 to 14 kPa. The primary outcome for this study was AKI according to KDIGO (Kidney Disease: Improving Global Outcomes) classification in patients surviving at least 48 hours (N=759). Adjusted logistic regression was performed for patients allocated to high blood pressure and liberal oxygen target as reference. RESULTS: The main population characteristics at admission were: age, 64 (54-73) years; 80% male; 90% shockable rhythm; and time to return of spontaneous circulation, 18 (12-26) minutes. Patients allocated to a low blood pressure and liberal oxygen target had an increased risk of developing AKI compared with patients with high blood pressure and liberal oxygen target (84/193 [44%] versus 56/187 [30%]; adjusted odds ratio, 1.87 [95% CI, 1.21-2.89]). Multinomial logistic regression revealed that the increased risk of AKI was only related to mild-stage AKI (KDIGO stage 1). There was no difference in risk of AKI in the other groups. Plasma creatinine remained high during hospitalization in the low blood pressure and liberal oxygen target group but did not differ between groups at 6- and 12-month follow-up. CONCLUSIONS: In comatose patients who had been resuscitated after out-of-hospital cardiac arrest, patients allocated to a combination of a low mean arterial blood pressure and a liberal oxygen target had a significantly increased risk of mild-stage AKI. No difference was found in terms of more severe AKI stages or other kidney-related adverse outcomes, and creatinine had normalized at 1 year after discharge. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03141099.

Bag-Valve-Mask Ventilation and Survival From Out-of-Hospital Cardiac Arrest: A Multicenter Study.

BACKGROUND: Few studies have measured ventilation during early cardiopulmonary resuscitation (CPR) before advanced airway placement. Resuscitation guidelines recommend pauses after every 30 chest compressions to deliver ventilations. The effectiveness of bag-valve-mask ventilation delivered during the pause in chest compressions is unknown. We sought to determine: (1) the incidence of lung inflation with bag-valve-mask ventilation during 30:2 CPR; and (2) the association of ventilation with outcomes after out-of-hospital cardiac arrest. METHODS: We studied patients with out-of-hospital cardiac arrest from 6 sites of the Resuscitation Outcomes Consortium CCC study (Trial of Continuous Compressions versus Standard CPR in Patients with Out-of-Hospital Cardiac Arrest). We analyzed patients assigned to the 30:2 CPR arm with ≥2 minutes of thoracic bioimpedance signal recorded with a cardiac defibrillator/monitor. Detectable ventilation waveforms were defined as having a bioimpedance amplitude ≥0.5 Ω (corresponding to ≥250 mL VT) and a duration ≥1 s. We defined a chest compression pause as a 3- to 15-s break in chest compressions. We compared the incidence of ventilation and outcomes in 2 groups: patients with ventilation waveforms in <50% of pauses (group 1) versus those with waveforms in ≥50% of pauses (group 2). RESULTS: Among 1976 patients, the mean age was 65 years; 66% were male. From the start of chest compressions until advanced airway placement, mean±SD duration of 30:2 CPR was 9.8±4.9 minutes. During this period, we identified 26 861 pauses in chest compressions; 60% of patients had ventilation waveforms in <50% of pauses (group 1, n=1177), and 40% had waveforms in ≥50% of pauses (group 2, n=799). Group 1 had a median of 12 pauses and 2 ventilations per patient versus group 2, which had 12 pauses and 12 ventilations per patient. Group 2 had higher rates of prehospital return of spontaneous circulation (40.7% versus 25.2%; P<0.0001), survival to hospital discharge (13.5% versus 4.1%; P<0.0001), and survival with favorable neurological outcome (10.6% versus 2.4%; P<0.0001). These associations persisted after adjustment for confounders. CONCLUSIONS: In this study, lung inflation occurred infrequently with bag-valve-mask ventilation during 30:2 CPR. Lung inflation in ≥50% of pauses was associated with improved return of spontaneous circulation, survival, and survival with favorable neurological outcome.

Surgical Management and Mechanical Circulatory Support in High-Risk Pulmonary Embolisms: Historical Context, Current Status, and Future Directions: A Scientific Statement From the American Heart Association.

Acute pulmonary embolism is the third leading cause of cardiovascular death, with most pulmonary embolism-related mortality associated with acute right ventricular failure. Although there has recently been increased clinical attention to acute pulmonary embolism with the adoption of multidisciplinary pulmonary embolism response teams, mortality of patients with pulmonary embolism who present with hemodynamic compromise remains high when current guideline-directed therapy is followed. Because historical data and practice patterns affect current consensus treatment recommendations, surgical embolectomy has largely been relegated to patients who have contraindications to other treatments or when other treatment modalities fail. Despite a selection bias toward patients with greater illness, a growing body of literature describes the safety and efficacy of the surgical management of acute pulmonary embolism, especially in the hemodynamically compromised population. The purpose of this document is to describe modern techniques, strategies, and outcomes of surgical embolectomy and venoarterial extracorporeal membrane oxygenation and to suggest strategies to better understand the role of surgery in the management of pulmonary embolisms.

KIDS SAVE LIVES: Basic Life Support Education for Schoolchildren: A Narrative Review and Scientific Statement From the International Liaison Committee on Resuscitation.

BACKGROUND: Basic life support education for schoolchildren has become a key initiative to increase bystander cardiopulmonary resuscitation rates. Our objective was to review the existing literature on teaching schoolchildren basic life support to identify the best practices to provide basic life support training in schoolchildren. METHODS: After topics and subgroups were defined, a comprehensive literature search was conducted. Systematic reviews and controlled and uncontrolled prospective and retrospective studies containing data on students <20 years of age were included. RESULTS: Schoolchildren are highly motivated to learn basic life support. The CHECK-CALL-COMPRESS algorithm is recommended for all schoolchildren. Regular training in basic life support regardless of age consolidates long-term skills. Young children from 4 years of age are able to assess the first links in the chain of survival. By 10 to 12 years of age, effective chest compression depths and ventilation volumes can be achieved on training manikins. A combination of theoretical and practical training is recommended. Schoolteachers serve as effective basic life support instructors. Schoolchildren also serve as multipliers by passing on basic life support skills to others. The use of age-appropriate social media tools for teaching is a promising approach for schoolchildren of all ages. CONCLUSIONS: Schoolchildren basic life support training has the potential to educate whole generations to respond to cardiac arrest and to increase survival after out-of-hospital cardiac arrest. Comprehensive legislation, curricula, and scientific assessment are crucial to further develop the education of schoolchildren in basic life support.

Time to initiation of extracorporeal membrane oxygenation in conventional cardiopulmonary resuscitation affects the patient survival prognosis.

BACKGROUND: Cardiopulmonary resuscitation (CPR) is the cornerstone intervention for cardiac arrest, with extracorporeal CPR (ECPR) demonstrating enhanced survival and neurologic outcomes in in-hospital cardiac arrest. This study explores the time interval between CPR initiation and the onset of extracorporeal membrane oxygenation (ECMO) in ECPR recipients, investigating its impact on survival outcomes. METHODS: This retrospective analysis included 1950 adults who received CPR at a single medical center between March 2019 and April 2023. Data from 198 adult patients who had ECMO inserted during CPR were analyzed. The interval from CPR initiation to ECMO initiation was quantified and categorized as ≤20, 20-40, and >40 min. Cox regression analysis assessed associations between CPR-to-ECMO time and short- and long-term mortalities. RESULTS: Among the 198 patients who underwent ECPR, 116 (58.6%) experienced 30-day mortality. Initiation of ECMO within 20 min occurred in 46 (23.2%), whereas 74 (37.4%) had ECMO initiated after 40 min. Cox regression revealed a significant association between time from CPR to ECMO initiation and 30-day mortality (adjusted hazard ratio [HR]: 2.20 in >40 min, HR: 2.63 in 20-40 min, p = 0.006) and 6-month mortality (HR: 1.81, in >40 min, HR: 1.99 in 20-40 min, p = 0.021). CONCLUSIONS: This study revealed that, in ECPR recipients, a shorter duration between CPR initiation and ECMO flow commencement is associated with improved short- and long-term patient prognoses. These findings emphasize the critical role of timely ECMO application in optimizing outcomes for patients undergoing ECPR.

Therapeutic potential of mitochondrial transplantation in modulating immune responses post-cardiac arrest: a narrative review.

BACKGROUND: Mitochondrial transplantation (MTx) has emerged as a novel therapeutic strategy, particularly effective in diseases characterized by mitochondrial dysfunction. This review synthesizes current knowledge on MTx, focusing on its role in modulating immune responses and explores its potential in treating post-cardiac arrest syndrome (PCAS). METHODS: We conducted a comprehensive narrative review of animal and human studies that have investigated the effects of MTx in the context of immunomodulation. This included a review of the immune responses following critical condition such as ischemia reperfusion injury, the impact of MTx on these responses, and the therapeutic potential of MTx in various conditions. RESULTS: Recent studies indicate that MTx can modulate complex immune responses and reduce ischemia-reperfusion injury post-CA, suggesting MTx as a novel, potentially more effective approach. The review highlights the role of MTx in immune modulation, its potential synergistic effects with existing treatments such as therapeutic hypothermia, and the need for further research to optimize its application in PCAS. The safety and efficacy of autologous versus allogeneic MTx, particularly in the context of immune reactions, are critical areas for future investigation. CONCLUSION: MTx represents a promising frontier in the treatment of PCAS, offering a novel approach to modulate immune responses and restore cellular energetics. Future research should focus on long-term effects, combination therapies, and personalized medicine approaches to fully harness the potential of MTx in improving patient outcomes in PCAS.

Neuroprotection provided by hypothermia initiated with high transnasal flow with ambient air in a model of pediatric cardiac arrest.

Clinical trials of hypothermia after pediatric cardiac arrest (CA) have not seen robust improvement in functional outcome, possibly because of the long delay in achieving target temperature. Previous work in infant piglets showed that high nasal airflow, which induces evaporative cooling in the nasal mucosa, reduced regional brain temperature uniformly in half the time needed to reduce body temperature. Here, we evaluated whether initiation of hypothermia with high transnasal airflow provides neuroprotection without adverse effects in the setting of asphyxic CA. Anesthetized piglets underwent sham-operated procedures (n = 7) or asphyxic CA with normothermic recovery (38.5°C; n = 9) or hypothermia initiated by surface cooling at 10 (n = 8) or 120 (n = 7) min or transnasal cooling initiated at 10 (n = 7) or 120 (n = 7) min after resuscitation. Hypothermia was sustained at 34°C with surface cooling until 20 h followed by 6 h of rewarming. At 4 days of recovery, significant neuronal loss occurred in putamen and sensorimotor cortex. Transnasal cooling initiated at 10 min significantly rescued the number of viable neurons in putamen, whereas levels in putamen in other hypothermic groups remained less than sham levels. In sensorimotor cortex, neuronal viability in the four hypothermic groups was not significantly different from the sham group. These results demonstrate that early initiation of high transnasal airflow in a pediatric CA model is effective in protecting vulnerable brain regions. Because of its simplicity, portability, and low cost, transnasal cooling potentially could be deployed in the field or emergency room for early initiation of brain cooling after pediatric CA.NEW & NOTEWORTHY The onset of therapeutic hypothermia after cardiac resuscitation is often delayed, leading to incomplete neuroprotection. In an infant swine model of asphyxic cardiac arrest, initiation of high transnasal airflow to maximize nasal evaporative cooling produced hypothermia sufficient to provide neuroprotection that was not inferior to body surface cooling. Because of its simplicity and portability, this technique may be of use in the field or emergency room for rapid brain cooling in pediatric cardiac arrest victims.

Insufficient oxygen inhalation during cardiopulmonary resuscitation induces early changes in hemodynamics followed by late and unfavorable systemic responses in post-cardiac arrest rats.

Cardiac arrest (CA) and concomitant post-CA syndrome lead to a lethal condition characterized by systemic ischemia-reperfusion injury. Oxygen (O2 ) supply during cardiopulmonary resuscitation (CPR) is the key to success in resuscitation, but sustained hyperoxia can produce toxic effects post CA. However, only few studies have investigated the optimal duration and dosage of O2 administration. Herein, we aimed to determine whether high concentrations of O2 at resuscitation are beneficial or harmful. After rats were resuscitated from the 10-min asphyxia, mechanical ventilation was restarted at an FIO2 of 1.0 or 0.3. From 10 min after initiating CPR, FIO2 of both groups were maintained at 0.3. Bio-physiological parameters including O2 consumption (VO2 ) and mRNA gene expression in multiple organs were evaluated. The FIO2 0.3 group decreased VO2 , delayed the time required to achieve peak MAP, lowered ejection fraction (75.1 ± 3.3% and 59.0 ± 5.7% with FIO2 1.0 and 0.3, respectively; p < .05), and increased blood lactate levels (4.9 ± 0.2 mmol/L and 5.6 ± 0.2 mmol/L, respectively; p < .05) at 10 min after CPR. FIO2 0.3 group had significant increases in hypoxia-inducible factor, inflammatory, and apoptosis-related mRNA gene expression in the brain. Likewise, significant upregulations of hypoxia-inducible factor and apoptosis-related gene expression were observed in the FIO2 0.3 group in the heart and lungs. Insufficient O2 supplementation in the first 10 min of resuscitation could prolong ischemia, and may result in unfavorable biological responses 2 h after CA. Faster recovery from the impairment of O2 metabolism might contribute to the improvement of hemodynamics during the early post-resuscitation phase; therefore, it may be reasonable to provide the maximum feasible O2 concentrations during CPR.

Adenosine 2A Receptor Agonism Improves Survival in Extracorporeal Cardiopulmonary Resuscitation.

INTRODUCTION: Despite resuscitation advances including extracorporeal cardiopulmonary resuscitation (ECPR), freedom from neurologic and myocardial insult after cardiac arrest remains unlikely. We hypothesized that adenosine 2A receptor (A2AR) agonism, which attenuates reperfusion injury, would improve outcomes in a porcine model of ECPR. METHODS: Adult swine underwent 20 min of circulatory arrest followed by defibrillation and 6 h of ECPR. Animals were randomized to receive saline vehicle or A2AR agonist (ATL1223 or Regadenoson) infusion during extracorporeal membrane oxygenation. Animals were weaned off extracorporeal membrane oxygenation and monitored for 24 h. Clinical and biochemical end points were compared. RESULTS: The administration of A2AR agonists increased survival (P = 0.01) after cardiac arrest compared to vehicle. Markers of neurologic damage including S100 calcium binding protein B and glial fibrillary acidic protein were significantly lower with A2AR agonist treatment. CONCLUSIONS: In a model of cardiac arrest treated with ECPR, A2AR agonism increased survival at 24 h and reduced neurologic damage suggesting A2AR activation may be a promising therapeutic target after cardiac arrest.

Survival of In-Hospital Cardiopulmonary Arrest in Trauma Patients.

INTRODUCTION: Relative to other hospitalized patients, trauma patients are younger with fewer comorbidities, but the incidence and outcomes of in-hospital cardiopulmonary arrest (IHCA) with cardiopulmonary resuscitation (CPR) in this population is unknown. Therefore, we aimed to investigate factors associated with survival in trauma patients after IHCA to test the hypothesis that compared to other hospitalized patients, trauma patients with IHCA have improved survival. METHODS: Retrospective review of the Trauma Quality Improvement Program database 2017 to 2019 for patients who had IHCA with CPR. Primary outcome was survival to hospital discharge. Secondary outcomes were in-hospital complications, hospital length of stay, intensive care unit length of stay, and ventilator days. Data were compared with univariate and multivariate analyses at P < 0.05. RESULTS: In 22,346,677 admitted trauma patients, 14,056 (0.6%) received CPR. Four thousand three hundred seventy-seven (31.1%) survived to discharge versus 26.4% in a national sample of all hospitalized patients (P < 0.001). In trauma patients, median age was 55 y, the majority were male (72.2%). Mortality was higher for females versus males (70.3% versus 68.3%, P = 0.026). Multivariate regression showed that older age 1.01 (95% confidence interval (CI) 1.01-1.02), Hispanic ethnicity 1.21 (95% CI 1.04-1.40), and penetrating trauma 1.51 (95% CI 1.32-1.72) were risk factors for mortality, while White race was a protective factor 0.36 (95% CI 0.14-0.89). CONCLUSIONS: This is the first study to show that the incidence of IHCA with CPR is approximately six in 1000 trauma admissions and 31% survive to hospital discharge, which is higher than other hospitalized patients. Age, gender, racial, and ethnic disparities also influence survival.

The association of depression and patient and resuscitation characteristics with survival after out-of-hospital cardiac arrest: a cohort study.

AIMS: Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide, with cardiovascular disease (CVD) being a key risk factor. This study aims to investigate disparities in patient/OHCA characteristics and survival after OHCA among patients with vs. without depression. METHODS AND RESULTS: This is a retrospective cohort study using data from the AmsteRdam REsuscitation Studies (ARREST) registry from 2008 to 2018. History of comorbidities, including depression, was obtained from the patient's general practitioner. Out-of-hospital cardiac arrest survival was defined as survival at 30 days post-OHCA or hospital discharge. Logistic regression models were used to obtain crude and adjusted odds ratios (ORs) for the association between depression and OHCA survival and possible effect modification by age, sex, and comorbidities. The potential mediating effects of initial heart rhythm and provision of bystander cardiopulmonary resuscitation were explored. Among 5594 OHCA cases, 582 individuals had pre-existing depression. Patients with depression had less favourable patient and OHCA characteristics and lower odds of survival after adjustment for age, sex, and comorbidities [OR 0.65, 95% confidence interval (CI) 0.51-0.82], with similar findings by sex and age groups. The association remained significant among the Utstein comparator group (OR 0.63, 95% CI 0.45-0.89) and patients with return of spontaneous circulation (OR 0.60, 95% CI 0.42-0.85). Initial rhythm and bystander cardiopulmonary resuscitation partially mediated the observed association (by 27 and 7%, respectively). CONCLUSION: Out-of-hospital cardiac arrest patients with depression presented more frequently with unfavourable patient and OHCA characteristics and had reduced chances of survival. Further investigation into potential pathways is warranted.

Impact of extracorporeal membrane oxygenation treatments on acquired von Willebrand syndrome in patients with out-of-hospital cardiac arrest: a retrospective observational study.

BACKGROUND: Von Willebrand factor (vWF) plays a crucial role in hemostasis, acting as a key factor for platelet adhesion/aggregation and as a transport protein for coagulation factor VIII. vWF is secreted as a giant multimer, and it undergoes shear stress-dependent cleavage by a specific metalloproteinase in plasma. Among vWF multimers, high-molecular-weight (large) multimers are essential for hemostasis. Acquired von Willebrand syndrome, linked to various conditions, is a hemostatic disorder due to reduced vWF activity. Extracorporeal membrane oxygenation (ECMO), utilized recently for out-of-hospital cardiac arrest patients, generates high shear stress inside the pump. This stress may induce a conformational change in vWF, enhancing cleavage by a specific metalloproteinase and thereby reducing vWF activity. However, no study has investigated the effects of ECMO on vWF-related factors in patients receiving or not receiving ECMO. This study aimed to elucidate the relationship between ECMO treatment and acquired von Willebrand syndrome-related factors in patients with out-of-hospital cardiac arrest. METHODS: This study included patients with cardiogenic out-of-hospital cardiac arrest admitted to our hospital. The patients were categorized into two groups (ECMO and non-ECMO) based on the presence or absence of ECMO treatment. Plasma samples were collected from patients admitted to the emergency department (days 0-4). The vWF antigen (vWF: Ag), vWF ristocetin cofactor activity (vWF: RCo), and factor VIII activity were measured. Additionally, a large multimer of vWF was evaluated through vWF multimer analysis, utilizing western blotting to probe vWF under non-reducing conditions. RESULTS: The ECMO and non-ECMO groups included 10 and 22 patients, respectively. The median ECMO treatment in the ECMO group was 64.6 h. No differences in vWF: Ag or factor VIII activity were observed between the two groups during the observation period. However, the ECMO group exhibited a decrease in large vWF multimers and vWF: RCo during ECMO. Strong correlations were observed between vWF: RCo and vWF: Ag in both groups, although the relationships were significantly different between the two groups. CONCLUSIONS: ECMO treatment in patients with out-of-hospital cardiac arrest resulted in the loss of large vWF multimers and decreased vWF activity. Hence, decreased vWF activity should be considered as a cause of bleeding during ECMO management.

Extracorporeal cardiopulmonary resuscitation versus conventional CPR in cardiac arrest: an updated meta-analysis and trial sequential analysis.

BACKGROUND: Extracorporeal cardiopulmonary resuscitation (ECPR) may reduce mortality and improve neurological outcomes in patients with cardiac arrest. We updated our existing meta-analysis and trial sequential analysis to further evaluate ECPR compared to conventional CPR (CCPR). METHODS: We searched three international databases from 1 January 2000 through 1 November 2023, for randomised controlled trials or propensity score matched studies (PSMs) comparing ECPR to CCPR in both out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA). We conducted an updated random-effects meta-analysis, with the primary outcome being in-hospital mortality. Secondary outcomes included short- and long-term favourable neurological outcome and survival (30 days-1 year). We also conducted a trial sequential analysis to evaluate the required information size in the meta-analysis to detect a clinically relevant reduction in mortality. RESULTS: We included 13 studies with 14 pairwise comparisons (6336 ECPR and 7712 CCPR) in our updated meta-analysis. ECPR was associated with greater precision in reducing overall in-hospital mortality (OR 0.63, 95% CI 0.50-0.79, high certainty), to which the trial sequential analysis was concordant. The addition of recent studies revealed a newly significant decrease in mortality in OHCA (OR 0.62, 95% CI 0.45-0.84). Re-analysis of relevant secondary outcomes reaffirmed our initial findings of favourable short-term neurological outcomes and survival up to 30 days. Estimates for long-term neurological outcome and 90-day-1-year survival remained unchanged. CONCLUSIONS: We found that ECPR reduces in-hospital mortality, improves neurological outcome, and 30-day survival. We additionally found a newly significant benefit in OHCA, suggesting that ECPR may be considered in both IHCA and OHCA.