Association between sub-phenotypes identified using latent class analysis and neurological outcomes in patients with out-of-hospital cardiac arrest in Japan.

BACKGROUND: In patients who experience out-of-hospital cardiac arrest (OHCA), it is important to assess the association of sub-phenotypes identified by latent class analysis (LCA) using pre-hospital prognostic factors and factors measurable immediately after hospital arrival with neurological outcomes at 30 days, which would aid in making treatment decisions. METHODS: This study retrospectively analyzed data obtained from the Japanese OHCA registry between June 2014 and December 2019. The registry included a complete set of data on adult patients with OHCA, which was used in the LCA. The association between the sub-phenotypes and 30-day survival with favorable neurological outcomes was investigated. Furthermore, adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by multivariate logistic regression analysis using in-hospital data as covariates. RESULTS: A total of, 22,261 adult patients who experienced OHCA were classified into three sub-phenotypes. The factor with the highest discriminative power upon patient's arrival was Glasgow Coma Scale followed by partial pressure of oxygen. Thirty-day survival with favorable neurological outcome as the primary outcome was evident in 66.0% participants in Group 1, 5.2% in Group 2, and 0.5% in Group 3. The 30-day survival rates were 80.6%, 11.8%, and 1.3% in groups 1, 2, and 3, respectively. Logistic regression analysis revealed that the ORs (95% CI) for 30-day survival with favorable neurological outcomes were 137.1 (99.4-192.2) for Group 1 and 4.59 (3.46-6.23) for Group 2 in comparison to Group 3. For 30-day survival, the ORs (95%CI) were 161.7 (124.2-212.1) for Group 1 and 5.78 (4.78-7.04) for Group 2, compared to Group 3. CONCLUSIONS: This study identified three sub-phenotypes based on the prognostic factors available immediately after hospital arrival that could predict neurological outcomes and be useful in determining the treatment strategy of patients experiencing OHCA upon their arrival at the hospital.

Mortality, morbidity & clinical outcome with different types of vasopressors in out of hospital cardiac arrest patients- a systematic review and meta-analysis.

BACKGROUND & OBJECTIVE: Despite their continued use, the effectiveness and safety of vasopressors in post-cardiac arrest patients remain controversial. This study examined the efficacy of various vasopressors in cardiac arrest patients in terms of clinical, morbidity, and mortality outcomes. METHODS: A comprehensive literature search was performed using online databases (MeSH terms: MEDLINE (Ovid), CENTRAL (Cochrane Library), Embase (Ovid), CINAHL, Scopus, and Google Scholar) from 1997 to 2023 for relevant English language studies. The primary outcomes of interest for this study included short-term survival leading to death, return of spontaneous circulation (ROSC), survival to hospital discharge, neurological outcomes, survival to hospital admission, myocardial infarction, and incidence of arrhythmias. RESULTS: In this meta-analysis, 26 studies, including 16 RCTs and ten non-RCTs, were evaluated. The focus was on the efficacy of epinephrine, vasopressin, methylprednisolone, dopamine, and their combinations in medical emergencies. Epinephrine treatment was associated with better odds of survival to hospital discharge (OR = 1.52, 95%CI [1.20, 1.94]; p < 0.001) and achieving ROSC (OR = 3.60, 95% CI [3.45, 3.76], P < 0.00001)) over placebo but not in other outcomes of interest such as short-term survival/ death at 28-30 days, survival to hospital admission, or neurological function. In addition, our analysis indicates non-superiority of vasopressin or epinephrine vasopressin-plus-epinephrine therapy over epinephrine monotherapy except for survival to hospital admission where the combinatorial therapy was associated with better outcome (0.76, 95%CI [0.64, 0.92]; p = 0.004). Similarly, we noted the non-superiority of vasopressin-plus-methylprednisolone versus placebo. Finally, while higher odds of survival to hospital discharge (OR = 3.35, 95%CI [1.81, 6.2]; p < 0.001) and ROSC (OR = 2.87, 95%CI [1.97, 4.19]; p < 0.001) favoring placebo over VSE therapy were observed, the risk of lethal arrhythmia was not statistically significant. There was insufficient literature to assess the effects of dopamine versus other treatment modalities meta-analytically. CONCLUSION: This meta-analysis indicated that only epinephrine yielded superior outcomes among vasopressors than placebo, albeit limited to survival to hospital discharge and ROSC. Additionally, we demonstrate the non-superiority of vasopressin over epinephrine, although vasopressin could not be compared to placebo due to the paucity of data. The addition of vasopressin to epinephrine treatment only improved survival to hospital admission.

Outcomes and relevance of emergency percutaneous coronary angiography and intervention after resuscitated cardiac arrest: a retrospective study.

BACKGROUND: In patients resuscitated from cardiac arrest and displaying no ST-segment elevation on initial electrocardiogram (ECG), recent randomized trials indicated no benefits from early coronary angiography. How the results of such randomized studies apply to a real-world clinical context remains to be established. METHODS: We retrospectively analyzed a clinical database including all patients 18 yo or older admitted to our tertiary University Hospital from January 2017 to August 2020 after successful resuscitation of out-of-Hospital (OHCA) or In-Hospital (IHCA) cardiac arrest of presumed cardiac origin, and undergoing immediate coronary angiography, regardless of the initial rhythm and post-resuscitation ECG. The primary outcome of the study was survival at day 90 after cardiac arrest. Demographic data, characteristics of cardiac arrest, duration of resuscitation, laboratory values at admission, angiographic data and revascularization status were collected. Comparisons were performed according to the initial ECG (ST-segment elevation or not), and between survivors and non-survivors. Variables associated with the primary outcome were evaluated by univariate and multivariate regression analyses. RESULTS: We analyzed 147 patients (130 OHCA and 17 IHCA), including 67 with STEMI and 80 without STEMI (No STEMI). Immediate revascularization was performed in 65/67 (97%) STEMI and 15/80 (19%) no STEMI. Day 90 survival was significantly higher in STEMI (48/67, 72%) than no STEMI (44/80, 55%). In the latter patients, survival was not influenced by the revascularization status. In univariate and multivariate analyses, lower age, a shockable rhythm, shorter durations of no flow and low flow, and a lower initial blood lactate were associated with survival in both STEMI and no STEMI. In contrast, metabolic abnormalities, including lower initial plasma sodium and higher potassium were significantly associated with mortality only in the subgroup of no STEMI patients. CONCLUSIONS: Our results, obtained in a real-world clinical setting, indicate that an immediate coronary angiography is not associated with any survival advantage in patients resuscitated from cardiac arrest of presumed cardiac etiology without ST-segment elevation on initial ECG. Furthermore, we found that some early metabolic abnormalities may be associated with mortality in this population, which should deserve further investigation.

Vitamin D deficiency as a risk factor for sudden cardiac arrest: A multicenter case-control study.

BACKGROUND AND AIMS: Vitamin D is known to influence the risk of cardiovascular disease, which is a recognized risk factor for sudden cardiac arrest (SCA). However, the relationship between vitamin D and SCA is not well understood. Therefore, this study aims to investigate the association between vitamin D and SCA in out-of-hospital cardiac arrest (OHCA) patients compared to healthy controls. METHODS AND RESULTS: Using the Phase II Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiologic Surveillance (CAPTURES II) registry, a 1:1 propensity score-matched case-control study was conducted between 2017 and 2020. Serum 25-hydroxyvitamin D (vitamin D) levels in patients with OHCA (454 cases) and healthy controls (454 cases) were compared after matching for age, sex, cardiovascular risk factors, and lifestyle behaviors. The mean vitamin D levels were 14.5 ± 7.6 and 21.3 ± 8.3 ng/mL among SCA cases and controls, respectively. Logistic regression analysis was used adjusting for cardiovascular risk factors, lifestyle behaviors, corrected serum calcium levels, and estimated glomerular filtration rate (eGRF). The adjusted odds ratio (aOR) for vitamin D was 0.89 (95% confidence interval [CI] 0.87-0.91). The dose-response relationship demonstrated that vitamin D deficiency was associated with SCA incidence (severe deficiency, aOR 10.87, 95% CI 4.82-24.54; moderate deficiency, aOR 2.24, 95% CI 1.20-4.20). CONCLUSION: Vitamin D deficiency was independently and strongly associated with an increased risk of SCA, irrespective of cardiovascular and lifestyle factors, corrected calcium levels, and eGFR.

Use of Time-to-Event Analysis to Develop On-Scene Return of Spontaneous Circulation Prediction for Out-of-Hospital Cardiac Arrest Patients.

STUDY OBJECTIVE: We aimed to train and validate the time to on-scene return of spontaneous circulation prediction models using time-to-event analysis among out-of-hospital cardiac arrest patients. METHODS: Using a Korean population-based out-of-hospital cardiac arrest registry, we selected a total of 105,215 adults with presumed cardiac etiologies between 2013 and 2018. Patients from 2013 to 2017 and from 2018 were analyzed for training and test, respectively. We developed 4 time-to-event analyzing models (Cox proportional hazard [Cox], random survival forest, extreme gradient boosting survival, and DeepHit) and 4 classification models (logistic regression, random forest, extreme gradient boosting, and feedforward neural network). Patient characteristics and Utstein elements collected at the scene were used as predictors. Discrimination and calibration were evaluated by Harrell's C-index and integrated Brier score. RESULTS: Among the 105,215 patients (mean age 70 years and 64% men), 86,314 and 18,901 patients belonged to the training and test sets, respectively. On-scene return of spontaneous circulation was achieved in 5,240 (6.1%) patients in the former set and 1,709 (9.0%) patients in the latter. The proportion of emergency medical services (EMS) management was higher and scene time interval longer in the latter. Median time from EMS scene arrival to on-scene return of spontaneous circulation was 8 minutes for both datasets. Classification models showed similar discrimination and poor calibration power compared to survival models; Cox showed high discrimination with the best calibration (C-index [95% confidence interval]: 0.873 [0.865 to 0.882]; integrated Brier score at 30 minutes: 0.060). CONCLUSION: Incorporating time-to-event analysis could lead to improved performance in prediction models and contribute to personalized field EMS resuscitation decisions.

Different forms of bystander cardiopulmonary resuscitation in out-of-hospital cardiac arrest.

Out-of-hospital cardiac arrest (OHCA) is a major cause of death in the Western world with an estimated number of 275 000 treated with resuscitation attempts by the Emergency Medical Services (EMS) in Europe each year. Overall survival rates remain low, and most studies indicate that around 1 out 10 will survive to 30 days. Amongst the strongest factors associated with survival in OHCA is first recorded rhythm amendable to defibrillation, early defibrillation and prompt initiation of cardiopulmonary resuscitation (CPR). Overall, CPR started prior to EMS arrival has repeatedly been shown to be associated with survival rates 2-3 times higher compared with no such initiation. The primary goal of CPR is to generate sufficient blood flow to vital organs, mainly the brain and heart, until restoration of spontaneous circulation can be achieved. Barriers to the initiation of CPR by bystanders in OHCA include fear of being incapable, causing harm, and transmission of infectious diseases. Partly due to these barriers, and low rates of CPR, the concept of CPR with compression only was proposed as a simpler form of resuscitation with the aim to be more widely accepted by the public in the 1990s. But how reliable is the evidence supporting this simpler form of CPR, and are the outcomes after CO-CPR comparable to standard CPR?

Independent Functional Outcomes after Prolonged Coma following Cardiac Arrest: A Mechanistic Hypothesis.

OBJECTIVE: Survivors of prolonged (>2 weeks) post-cardiac arrest (CA) coma are expected to remain permanently disabled. We aimed to investigate 3 outlier patients who ultimately achieved independent functional outcomes after prolonged post-CA coma to identify electroencephalographic (EEG) markers of their recovery potential. For validation purposes, we also aimed to evaluate these markers in an independent cohort of post-CA patients. METHODS: We identified 3 patients with late recovery from coma (17-37 days) following CA who recovered to functionally independent behavioral levels. We performed spectral power analyses of available EEGs during prominent burst suppression patterns (BSP) present in all 3 patients. Using identical methods, we also assessed the relationship of intraburst spectral power and outcomes in a prospectively enrolled cohort of post-CA patients. We performed chart reviews of common clinical, imaging, and EEG prognostic variables and clinical outcomes for all patients. RESULTS: All 3 patients with late recovery from coma lacked evidence of overwhelming cortical injury but demonstrated prominent BSP on EEG. Spectral analyses revealed a prominent theta (~4-7Hz) feature dominating the bursts during BSP in these patients. In the prospective cohort, similar intraburst theta spectral features were evident in patients with favorable outcomes; patients with BSP and unfavorable outcomes showed either no features, transient burst features, or decreasing intraburst frequencies with time. INTERPRETATION: BSP with theta (~4-7Hz) peak intraburst spectral power after CA may index a recovery potential. We discuss our results in the context of optimizing metabolic substrate availability and stimulating the corticothalamic system during recovery from prolonged post-CA coma. ANN NEUROL 2020;87:618-632.

Trend in survival after out-of-hospital cardiac arrest and its relationship with bystander cardiopulmonary resuscitation: a six-year prospective observational study in Beijing.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA), a global health problem with a survival rate ranging from 2 to 22% across different countries, has been a leading cause of premature death for decades. The aim of this study was to evaluate the trends of survival after OHCA over time and its relationship with bystander cardiopulmonary resuscitation (CPR), initial shockable rhythm, return of spontaneous circulation (ROSC), and survived event. METHODS: In this prospective observational study, data of OHCA patients were collected following the "Utstein style" by the Beijing, China, Emergency Medical Service (EMS) from January 2011 (data from February to June in 2011 was not collected) to October 2016. Patients who had a cardiac arrest and for whom an ambulance was dispatched were included in this study. All cases were followed up to determine hospital discharge or death. The trend of OHCA survival was analyzed using the Chi-square test. The relationship among bystander CPR, initial shockable rhythm, ROSC, survived event, and OHCA survival rate was analyzed using multivariate path analyses with maximum standard likelihood estimation. RESULTS: A total of 25,421 cases were transferred by the Beijing EMS; among them, 5042 (19.8%) were OHCA (median age: 78 years, interquartile range: 63-85, 60.1% male), and 484 (9.6%) received bystander CPR. The survival rate was 0.6%, which did not improve from 2012 to 2015 (P = 0.569). Overall, bystander CPR was indirectly associated with an 8.0% (ß = 0.080, 95% confidence interval [CI] = 0.064-0.095, P = 0.002) increase in survival rate. The indirect effect of bystander CPR on survival rate through survived event was 6.6% (ß = 0.066, 95% CI = 0.051-0.081, P = 0.002), which accounted for 82.5% (0.066 of 0.080) of the total indirect effect. With every 1 increase in survived event, the possibility of survival rate will directly increase by 53.5% (ß = 0.535, 95% CI = 0.512-0.554, P = 0.003). CONCLUSIONS: The survival rate after OHCA was low in Beijing which has not improved between 2012 and 2015. The effect of bystander CPR on survival rate was mainly mediated by survived event. Trial registration Chinese Clinical Trial Registry: ChiCTR-TRC-12002149 (2 May, 2012, retrospectively registered). http://www.chictr.org.cn/showproj.aspx?proj=7400.

Do manual chest compressions provide substantial ventilation during prehospital cardiopulmonary resuscitation?

INTRODUCTION: Chest compressions have been suggested to provide passive ventilation during cardiopulmonary resuscitation. Measurements of this passive ventilatory mechanism have only been performed upon arrival of out-of-hospital cardiac arrest patients in the emergency department. Lung and thoracic characteristics rapidly change following cardiac arrest, possibly limiting the effectiveness of this mechanism after prolonged resuscitation efforts. Goal of this study was to quantify passive inspiratory tidal volumes generated by manual chest compression during prehospital cardiopulmonary resuscitation. MATERIALS AND METHODS: A flowsensor was used during adult out-of-hospital cardiac arrest cases attended by a prehospital medical team. Adult, endotracheally intubated, non-traumatic cardiac arrest patients were eligible for inclusion. Immediately following intubation, the sensor was connected to the endotracheal tube. The passive inspiratory tidal volumes generated by the first thirty manual chest compressions performed following intubation (without simultaneous manual ventilation) were calculated. RESULTS: 10 patients (5 female) were included, median age was 64 years (IQR 56, 77 years). The median compression frequency was 111 compression per minute (IQR 107, 116 compressions per minute). The median compression depth was 5.6 cm (IQR 5.4 cm, 6.1 cm). The median inspiratory tidal volume generated by manual chest compressions was 20 mL (IQR 13, 28 mL). CONCLUSION: Using a flowsensor, passive inspiratory tidal volumes generated by manual chest compressions during prehospital cardiopulmonary resuscitation, were quantified. Chest compressions alone appear unable to provide adequate alveolar ventilation during prehospital treatment of cardiac arrest.

Can bystanders' gender affect the clinical outcome of out-of-hospital cardiac arrest: A prospective, multicentre observational study.

BACKGROUND AND PURPOSE: Out-of-hospital cardiac arrest (OHCA) is one of the most common causes of death in many countries. For OHCA patients to have a good clinical outcome, bystander cardiopulmonary resuscitation (CPR) is extremely significant. It is necessary to study the various characteristics of bystanders to improve bystander CPR quality. We aimed to evaluate the correlation between bystanders' gender and clinical outcomes of patients with OHCA. METHODS: We conducted an observational study by using a prospective, multicenter registry of OHCA resuscitation, provided by the Korean Cardiac Arrest Research Consortium registry from October 2015 to June 2017. The following data were collected: patient's age, patient's gender, witnessed by a layperson, characteristics of the bystanders (age grouped by decade, gender, CPR education, compression method, and perception of automated external defibrillators), arrest place, emergency medical services arrival time, and initial electrocardiogram rhythms. Outcome variables were prehospital return of spontaneous circulation, survival discharge, and cerebral performance category status at discharge. RESULTS: A total of 691 patients were included in the study. There were significant differences in the initial shockable rhythm and previous CPR training between bystander's gender. Characteristics such as age, patient's gender, witnessed by a layperson, bystander's gender, initial shockable rhythm, and arrest place were significantly associated with neurologic outcome at discharge, using univariable analysis. However, in the multivariate logistic model, there was no significant correlation between bystander's gender and neurologic outcome. In the subgroup analysis using the multivariate logistic model with 291 patients without missing values of CPR education and bystander' age, there was a significant difference in neurologic outcome depending on bystander's CPR education status. CONCLUSION: There was no difference in the neurologic outcomes of OHCA patients based on bystanders' gender. However, according to subgroup analysis, there was a difference in the neurologic outcome depending on the status of bystanders' CPR education and females received less CPR education than males. Therefore, more active CPR education is required.

Circulatory trajectories after out-of-hospital cardiac arrest: a prospective cohort study.

BACKGROUND: Circulatory failure frequently occurs after out-of-hospital cardiac arrest (OHCA) and is part of post-cardiac arrest syndrome (PCAS). The aim of this study was to investigate circulatory disturbances in PCAS by assessing the circulatory trajectory during treatment in the intensive care unit (ICU). METHODS: This was a prospective single-center observational cohort study of patients after OHCA. Circulation was continuously and invasively monitored from the time of admission through the following five days. Every hour, patients were classified into one of three predefined circulatory states, yielding a longitudinal sequence of states for each patient. We used sequence analysis to describe the overall circulatory development and to identify clusters of patients with similar circulatory trajectories. We used ordered logistic regression to identify predictors for cluster membership. RESULTS: Among 71 patients admitted to the ICU after OHCA during the study period, 50 were included in the study. The overall circulatory development after OHCA was two-phased. Low cardiac output (CO) and high systemic vascular resistance (SVR) characterized the initial phase, whereas high CO and low SVR characterized the later phase. Most patients were stabilized with respect to circulatory state within 72 h after cardiac arrest. We identified four clusters of circulatory trajectories. Initial shockable cardiac rhythm was associated with a favorable circulatory trajectory, whereas low base excess at admission was associated with an unfavorable circulatory trajectory. CONCLUSION: Circulatory failure after OHCA exhibits time-dependent characteristics. We identified four distinct circulatory trajectories and their characteristics. These findings may guide clinical support for circulatory failure after OHCA. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02648061.

QRS complex characteristics and patient outcomes in out-of-hospital pulseless electrical activity cardiac arrest.

BACKGROUND: Pulseless electrical activity (PEA) is increasingly observed in out-of-hospital cardiac arrest (OHCA), but outcomes are still poor. We aimed to assess the relationship between QRS characteristics and outcomes of patients with OHCA with initial PEA (OHCA-P). METHODS: This prospective observational study included patients aged at least 18 years who developed OHCA-P between 1 January 2016 and 31 December 2018, and were enrolled in the Daegu Emergency Medical Services registry, South Korea. We performed multivariable logistic regression analyses to identify the associations between QRS characteristics and OHCA-P outcomes, in which QRS complexes were considered separately (model 1) and simultaneously (model 2). The primary outcome was survival to hospital discharge and the secondary outcome was a favourable neurological outcome. RESULTS: Of the 3659 patients with OHCA, 576 were enrolled (median age 73 years; 334 men). A higher QRS amplitude was associated with survival to hospital discharge and a favourable neurological outcome in model 1 (adjusted OR (aOR) 1.077 and 1.106, respectively; 95% CI 1.021 to 0.136 and 1.029 to 1.190, respectively) and model 2 (aOR 1.084 and 1.123, respectively; 95% CI 1.026 to 1.145 and 1.036 to 1.216, respectively). A QRS width of <120 ms was associated with survival to hospital discharge and a favourable neurological outcome in model 1 (aOR 3.371 and 4.634, respectively; 95% CI 1.633 to 6.960 and 1.562 to 13.144, respectively) and model 2 (aOR 3.213 and 5.103, respectively; 95% CI 1.568 to 6.584 and 1.682 to 15.482, respectively). Survival to hospital discharge and neurological outcome were not associated with QRS frequency. CONCLUSION: OHCA-P outcomes were better when the initial QRS complex showed a higher amplitude or narrower width.

Effect of Intravenous or Intraosseous Calcium vs Saline on Return of Spontaneous Circulation in Adults With Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial.

Importance: It is unclear whether administration of calcium has a beneficial effect in patients with cardiac arrest. Objective: To determine whether administration of calcium during out-of-hospital cardiac arrest improves return of spontaneous circulation in adults. Design, Setting, and Participants: This double-blind, placebo-controlled randomized clinical trial included 397 adult patients with out-of-hospital cardiac arrest and was conducted in the Central Denmark Region between January 20, 2020, and April 15, 2021. The last 90-day follow-up was on July 15, 2021. Interventions: The intervention consisted of up to 2 intravenous or intraosseous doses with 5 mmol of calcium chloride (n = 197) or saline (n = 200). The first dose was administered immediately after the first dose of epinephrine. Main Outcomes and Measures: The primary outcome was sustained return of spontaneous circulation. The secondary outcomes included survival and a favorable neurological outcome (modified Rankin Scale score of 0-3) at 30 days and 90 days. Results: Based on a planned interim analysis of 383 patients, the steering committee stopped the trial early due to concerns about harm in the calcium group. Of 397 adult patients randomized, 391 were included in the analyses (193 in the calcium group and 198 in the saline group; mean age, 68 [SD, 14] years; 114 [29%] were female). There was no loss to follow-up. There were 37 patients (19%) in the calcium group who had sustained return of spontaneous circulation compared with 53 patients (27%) in the saline group (risk ratio, 0.72 [95% CI, 0.49 to 1.03]; risk difference, -7.6% [95% CI, -16% to 0.8%]; P = .09). At 30 days, 10 patients (5.2%) in the calcium group and 18 patients (9.1%) in the saline group were alive (risk ratio, 0.57 [95% CI, 0.27 to 1.18]; risk difference, -3.9% [95% CI, -9.4% to 1.3%]; P = .17). A favorable neurological outcome at 30 days was observed in 7 patients (3.6%) in the calcium group and in 15 patients (7.6%) in the saline group (risk ratio, 0.48 [95% CI, 0.20 to 1.12]; risk difference, -4.0% [95% CI, -8.9% to 0.7%]; P = .12). Among the patients with calcium values measured who had return of spontaneous circulation, 26 (74%) in the calcium group and 1 (2%) in the saline group had hypercalcemia. Conclusions and Relevance: Among adults with out-of-hospital cardiac arrest, treatment with intravenous or intraosseous calcium compared with saline did not significantly improve sustained return of spontaneous circulation. These results do not support the administration of calcium during out-of-hospital cardiac arrest in adults. Trial Registration: ClinicalTrials.gov Identifier: NCT04153435.

Public Perceptions on Why Women Receive Less Bystander Cardiopulmonary Resuscitation Than Men in Out-of-Hospital Cardiac Arrest.

BACKGROUND: Women who suffer an out-of-hospital cardiac arrest receive bystander cardiopulmonary resuscitation (CPR) less often than men. Understanding public perceptions of why this occurs is a necessary first step toward equitable application of this potentially life-saving intervention. METHODS: We conducted a national survey of members of the public using Mechanical Turk, Amazon's crowdsourcing platform, to determine reasons why women might receive bystander CPR less often than men. Eligible participants were adults (≥18 years) located in the United States. Responses were excluded if the participant was not able to define CPR correctly. Participants were asked to answer the following free-text question: "Do you have any ideas on why women may be less likely to receive CPR than men when they collapse in public?" Descriptive statistics were used to define the cohort. The free-text response was coded using open coding, and major themes were identified via classical content analysis. RESULTS: In total, 548 subjects were surveyed. Mean age was 38.8 years, and 49.8% were female. Participants were geographically distributed as follows: 18.5% West, 9.2% Southwest, 22.0% Midwest, 27.5% Southeast, and 22.9% Northeast. After analysis, 3 major themes were detected for why the public perceives that women receive less bystander CPR. They include the following: (1) sexualization of women's bodies; (2) women are weak and frail and therefore prone to injury; and (3) misperceptions about women in acute medical distress. Overall, 41.9% (227) were trained in CPR while 4.4% reported having provided CPR in a medical emergency. CONCLUSIONS: Members of the general public perceive fears about inappropriate touching, accusations of sexual assault, and fear of causing injury as inhibiting bystander CPR for women. Educational and policy efforts to address these perceptions may reduce the sex differences in the application of bystander CPR.

Ambulance Density and Outcomes After Out-of-Hospital Cardiac Arrest.

BACKGROUND: In out-of-hospital cardiac arrest (OHCA), geographic disparities in outcomes may reflect baseline variations in patients' characteristics but may also result from differences in the number of ambulances providing basic life support (BLS) and advanced life support (ALS). We aimed at assessing the association between allocated ambulance resources and outcomes in OHCA patients in a large urban community. METHODS: From May 2011 to January 2016, we analyzed a prospectively collected Utstein database for all OHCA adults. Cases were geocoded according to 19 neighborhoods and the number of BLS (firefighters performing cardiopulmonary resuscitation and applying automated external defibrillator) and ALS ambulances (medicalized team providing advanced care such as drugs and endotracheal intubation) was collected. We assessed the respective associations of Utstein parameters, socioeconomic characteristics, and ambulance resources of these neighborhoods using a mixed-effect model with successful return of spontaneous circulation as the primary end point and survival at hospital discharge as a secondary end point. RESULTS: During the study period, 8754 nontraumatic OHCA occurred in the Greater Paris area. Overall return of spontaneous circulation rate was 3675 of 8754 (41.9%) and survival rate at hospital discharge was 788 of 8754 (9%), ranging from 33% to 51.1% and from 4.4% to 14.5% respectively, according to neighborhoods ( P<0.001). Patient and socio-demographic characteristics significantly differed between neighborhoods ( P for trend <0.001). After adjustment, a higher density of ambulances was associated with successful return of spontaneous circulation (respectively adjusted odds-ratio [aOR], 1.31 [1.14-1.51]; P<0.001 for ALS ambulances >1.5 per neighborhood and aOR, 1.21 [1.04-1.41]; P=0.01 for BLS ambulances >4 per neighborhood). Regarding survival at discharge, only the number of ALS ambulances >1.5 per neighborhood was significant (aOR, 1.30 [1.06-1.59] P=0.01). CONCLUSIONS: In this large urban population-based study of out-of-hospital cardiac arrests patients, we observed that allocated resources of emergency medical service are associated with outcome, suggesting that improving healthcare organization may attenuate disparities in prognosis.

Proteomics-Enriched Prediction Model for Poor Neurologic Outcome in Cardiac Arrest Survivors.

OBJECTIVES: Neurologic outcome prediction in out-of-hospital cardiac arrest survivors is highly limited due to the lack of consistent predictors of clinically relevant brain damage. The present study aimed to identify novel biomarkers of neurologic recovery to improve early prediction of neurologic outcome. DESIGN: Prospective, single-center study, SETTING:: University-affiliated tertiary care center. PATIENTS: We prospectively enrolled 96 out-of-hospital cardiac arrest survivors into our study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Neurologic outcome was assessed by the Cerebral Performance Categories score. To identify plasma biomarkers for poor neurologic outcome (Cerebral Performance Categories score ≥ 3), we performed a three-step proteomics strategy of preselection by shotgun analyses, crosschecking in brain tissue samples, and verification by targeted proteomic analyses using a multistep statistical modeling approach. Sixty-three patients (66%) had a poor neurologic outcome. Out of a total of 299 proteins, we identified α-enolase, 14-3-3 protein ζ/δ, cofilin-1, and heat shock cognate 71 kDa protein as novel biomarkers for poor neurologic outcome. The implementation of these biomarkers into a clinical multimarker model, consisting of previously identified covariates associated to outcome, resulted in a significant improvement of neurologic outcome prediction (C-index, 0.70; explained variation, 11.9%; p for added value, 0.019). CONCLUSIONS: This study identified four novel biomarkers for the prediction of poor neurologic outcome in out-of-hospital cardiac arrest survivors. The implementation of α-enolase, 14-3-3 protein ζ/δ, cofilin-1, and heat shock cognate 71 kDa protein into a multimarker predictive model along with previously identified risk factors significantly improved neurologic outcome prediction. Each of the proteomically identified biomarkers did not only outperform current risk stratification models but may also reflect important pathophysiologic pathways undergoing during cerebral ischemia.

Epinephrine for Out-of-Hospital Cardiac Arrest: An Updated Systematic Review and Meta-Analysis.

OBJECTIVES: To perform an updated systematic review and meta-analysis of clinical trials evaluating epinephrine for adult out-of-hospital cardiac arrest resuscitation. DATA SOURCES: The search included MEDLINE, EMBASE, and Ovid Evidence-Based Medicine, clinical trial registries, and bibliographies. STUDY SELECTION: Randomized and quasi-randomized controlled trials that compared the current standard dose of epinephrine to placebo, high or low dose epinephrine, any other vasopressor alone or in combination were screened by three independent reviewers. DATA EXTRACTION: Randomized and quasi-randomized controlled trials that compared the current standard dose of epinephrine to placebo, high or low dose epinephrine, any other vasopressor alone or in combination were screened by three independent reviewers. DATA SYNTHESIS: A total of 17 trials (21,510 patients) were included; seven were judged to be at high risk of bias. Compared to placebo, pooled results from two trials showed that standard dose of epinephrine increased return of spontaneous circulation (risk ratio, 3.09; 95% CI, 2.82-3.89), survival to hospital admission (risk ratio, 2.50; 95% CI, 1.68-3.72), and survival to discharge (risk ratio, 1.44; 95% CI, 1.11-1.86). The largest placebo-controlled trial showed that standard dose of epinephrine also improved survival at 30 days and 3 months but not neurologic outcomes, standard dose of epinephrine decreased return of spontaneous circulation (risk ratio, 0.87; 95% CI, 0.77-0.98) and survival to admission (risk ratio, 0.88; 95% CI, 0.78-0.99) when compared with high dose epinephrine. There were no differences in outcomes between standard dose of epinephrine and vasopressin alone or in combination with epinephrine. CONCLUSIONS: Largely based on one randomized controlled trial, standard dose of epinephrine improved overall survival but not neurologic outcomes in out-of-hospital cardiac arrest patients compared with placebo. There is a paucity of trials with meaningful patient outcomes; future epinephrine trials should evaluate dose and method of delivery on long-term survival, neurologic function, and quality of life after cardiac arrest.

Prognostic Impact of No-Flow Time on 30-Day Neurological Outcomes in Patients With Out-of-Hospital Cardiac Arrest Who Received Extracorporeal Cardiopulmonary Resuscitation.

BACKGROUND: How the time sequence of cardiopulmonary resuscitation (CPR) procedures is related to clinical outcomes in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. This study examined the impact of the time interval from collapse to start of CPR (no-flow time, NF time) and the time interval from start of CPR to implementation of extracorporeal CPR (ECPR) (low-flow time, LF time) on neurological outcomes.Methods and Results:During the period from 2010 to 2015, we enrolled 85 patients who received ECPR. Fourteen patients (16.5%) showed favorable 30-day neurological recovery. NF time was shorter in the favorable neurological recovery group than in the unfavorable recovery group (1.4±3.0 vs. 5.2±5.8 min, P<0.05), though combined NF+LF times were similar in the 2 groups (50.1±13.2 vs. 55.1±14.8 min, P=0.25). Multivariate logistic regression analysis indicated that pupil diameter at arrival and NF time were independently associated with favorable neurological recovery. The optimal cut-off value of NF time to predict favorable neurological recovery was 5 min (area under curve: 0.70, P<0.05; sensitivity, 85.7%; specificity, 52.1%). CONCLUSIONS: The results suggest that NF time is a better predictor than NF+LF time for neurological outcomes in OHCA patients who received ECPR, and that start of CPR within 5 min after collapse is crucial for improving neurological outcomes followed by use of ECPR.

Heart Rate After Resuscitation From Out-of-Hospital Cardiac Arrest due to Acute Coronary Syndrome Is an Independent Predictor of Clinical Outcome.

BACKGROUND: Heart rate (HR) is a useful predictor of cardiovascular disease, especially in acute coronary syndrome (ACS). However, it is unclear whether there is an association between HR and clinical outcomes after resuscitation from out-of-hospital cardiac arrest (OHCA) due to ACS. The aim of this study was to investigate the impact of HR on clinical outcome in individuals resuscitated from OHCA due to ACS.Methods and Results:Data from 3,687 OHCA patients between October 2002 and October 2014 were retrospectively analyzed. We divided 154 patients diagnosed with ACS into 2 groups: those with tachycardia (HR >100 beats/min, n=71) and those without tachycardia (HR ≤100 beats/min, n=83) after resuscitation. The primary endpoint was 1-year mortality and the secondary endpoint was neurological injury at discharge according to cerebral performance category score. Overall, mean HR was 95.6 beats/min. There were several significant differences in patient characteristics, indicating poor general condition of patients with tachycardia. Mortality at 1-year was 41.6%, and neurological injury at discharge was observed in 44.1% of individuals. In the multivariate analysis, tachycardia after resuscitation was an independent predictor of both 1-year mortality (hazard ratio, 2.66; 95% CI: 1.20-5.85; P=0.03) and neurological injury at discharge (odds ratio, 2.65; 95% CI: 1.27-5.55; P=0.04). CONCLUSIONS: In patients who recovered from OHCA due to ACS, tachycardia after resuscitation predicted poor clinical outcome.

Characteristics and Outcomes of Out-of-Hospital Cardiac Arrest in Educational Institutions in Japan　- All-Japan Utstein Registry.

BACKGROUND: Although schools are key places that conduct cardiopulmonary resuscitation (CPR) and public-access defibrillation (PAD) programs, out-of-hospital cardiac arrest (OHCA) in educational institutions is poorly understood. This study describes the characteristics and outcomes of such OHCAs.Methods and Results:Data for OHCAs of any cause occurring in educational institutions between 2013 and 2015 were extracted from the All-Japan Utstein Registry. Patient characteristics and outcomes were documented. Subjects were divided into 6 age groups (0-1, 2-5, 6-11, 12-14, 15-17, and ≥18 years). Among the 783 eligible OHCA patients, most received bystander CPR regardless of age, ranging from 73.9% in those aged ≥18 years to 90.0% in those aged 2-5 years. However, the proportion receiving PAD differed by age group, ranging from 2.9% in those aged 0-1 years to 66.7% in those aged 12-14 years. The proportion of patients with 1-month survival with favorable neurological outcome differed significantly by age group, being extremely low among patients aged 0-1 years (zero for OHCA of cardiac origin), but high among patients aged 6-11, 12-14, and 15-17 years (69.2%, 77.5%, and 70.0%, respectively) for OHCA of cardiac origin. CONCLUSIONS: The outcomes of OHCA occurring in educational institutions, where PAD is available, differed significantly by age.