UNASSIGNED: Early defibrillation with an automated external defibrillator (AED) can effectively improve the survival rate of patients with out-of-hospital cardiac arrest (OHCA). Placing AEDs in public locations can reduce the defibrillation response interval from collapse to defibrillation. Most public AEDs are currently placed in a stationary way (S-AED) with limited coverage area. Bus mounted AED (B-AED) can be delivered directly to the demand point. Although B-AEDs are only available during bus operating hours, they provide greater coverage area. When the number of available AEDs is insufficient, better coverage may be achieved by placing a portion of AEDs as B-AEDs. Our purpose is developing a model to determine the optimal locations of B-AEDs and S-AEDs with a predetermined number of available AEDs. The goal is to maximize the total coverage level of all demand points.
UNASSIGNED: We proposed a joint location model to place B-AEDs and S-AEDs based on the p-median problem (JPMP). Using data from Chang\'an District, Xi\'an City, China, we determined the optimal AED deployment. The performance of JPMP was compared with several other models. The coverage results of JPMP are analyzed in details, including the quantity assignment, coverage level, and geographical location of B-AEDs and S-AEDs. The impact of the bus departure intervals on coverage was also discussed.
UNASSIGNED: The use of B-AEDs results in an average 98.43% increase in the number of covered demand points, and an average 74.05% increase in total coverage level. In optimal AED deployment, B-AEDs coverage follows an inverted U-shaped curve with increasing number of available AEDs. It begins to decrease when all demand points during the operating hours are covered. With a constant number of available AEDs, the total coverage level increases and then decreases as the bus departure interval increases. The larger the number of available AEDs, the smaller the optimal departure interval.
UNASSIGNED: With a given number of available AEDs, combinational deployment of B-AEDs and S-AEDs significantly improves the coverage level. B-AEDs are recommended when AEDs are insufficient. If more AEDs are available, better coverage can be obtained with reasonable location of S-AEDs and B-AEDs.

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

暂无摘要。

OBJECTIVE: During out-of-hospital cardiac arrest (OHCA), an automatic external defibrillator (AED) analyzes the cardiac rhythm every two minutes; however, 80% of refibrillations occur within the first minute post-shock. We have implemented an algorithm for Analyzing cardiac rhythm While performing chest Compression (AWC). When AWC detects a shockable rhythm, it shortens the time between analyses to one minute. We investigated the effect of AWC on cardiopulmonary resuscitation quality.
METHODS: In this cross-sectional study, we compared patients treated in 2022 with AWC, to a historical cohort from 2017. Inclusion criteria were OHCA patients with a shockable rhythm at the first analysis. Primary endpoint was the chest compression fraction (CCF). Secondary endpoints were cardiac rhythm evolution and survival, including survival analysis of non-prespecified subgroups.
RESULTS: In 2017 and 2022, 355 and 377 OHCAs met the inclusion criteria, from which we analyzed the 285 first consecutive cases in each cohort. CCF increased in 2022 compared to 2017 (77% [72-80] vs 72% [67-76]; P < 0.001) and VF recurrences were shocked more promptly (53 s [32-69] vs 117 s [90-132]). Survival did not differ between 2017 and 2022 (adjusted hazard-ratio 0.96 [95% CI, 0.78-1.18]), but was higher in 2022 within the sub-group of OHCAs that occurred in a public place and within a short time from call to AED switch-on (adjusted hazard ratio 0.85[0.76-0.96]).
CONCLUSIONS: OHCA patients treated with AWC had higher CCF, shorter time spent in ventricular fibrillation, but no survival difference, except for OHCA that occurred in public places with short intervention time.

Out-of-hospital cardiac arrest (OHCA) is a major cause of mortality worldwide, with a high incidence and low survival rate. Prompt cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use are major contributors in the \"chain of survival\" for OHCA. the response of a community plays a key role in determining the outcomes in OHCA. The outcomes of OHCA are affected by health inequalities in bystander CPR and AED use, due to factors such as differences in sex, ethnicity, and socioeconomic status amongst others. Literature shows patients from lower socio-economic backgrounds are more likely to have risk factors for a cardiac arrest and are therefore more likely to have OHCA. Studies have also reported lower rates of bystander AED use in females compared to males. Targeting deprived areas with tailored training and access to AEDs can be beneficial in improving CPR outcomes in communities. Due to the physical nature of CPR maneuvers, age and frailty of the patient can both impact the outcome of the resuscitation. Environmental factors affecting AED use include availability, visibility, accessibility, support, extra equipment, training materials, staffing, and awareness. Education should focus on areas such as conducting BLS on both male and female patients, recognizing cardiac arrest, tailoring BLS to difference ages as well as provision for training in different languages, including sign language. Like some other countries, CPR training is now being implemented in the school curriculum.

Intervention by members of the public during an out of hospital cardiac arrest (OHAC) including resuscitation attempts and accessible automated external defibrillator (AED) has been shown to improve survival. This study aimed to investigate the OHCA and AED knowledge and confidence, and barriers to intervention, of the public of North East England, UK. This study used a face-to-face cross-sectional survey on a public high street in Newcastle, UK. Participants were asked unprompted to explain what they would do when faced with an OHCA collapse. Chi-Square analysis was used to test the association of the independent variables sex and first aid trained on the participants\' responses. Of the 421 participants recruited to our study, 82.9% (n = 349) reported that they would know what to do during an OHCA collapse. The most frequent OHCA action mentioned was call 999 (64.1%, n = 270/421) and 58.2% (n = 245/421) of participants reported that they would commence CPR. However, only 14.3% (n = 60/421) of participants spontaneously mentioned that they would locate an AED, while only 4.5% (n = 19/421) recounted that they would apply the AED. Just over half of participants (50.8%, n = 214/421) were first aid trained, with statistically more females (57.3%, n = 126/220) than males (43.9%,  n = 87/198) being first aiders (p = 0.01 χ2 = 7.41). Most participants (80.3%, n = 338/421) knew what an AED was, and 34.7% (n = 326/421) reported that they knew how to use one, however, only 11.9% (n = 50/421) mentioned that they would actually shock a patient. Being first aid trained increased the likelihood of freely recounting actions for OHCA and AED intervention. The most common barrier to helping during an OHCA was lack of knowledge (29.9%, n = 126/421). Although most participants reported they would know what to do during an OHCA and had knowledge of an AED, low numbers of participants spontaneously mentioned specific OHCA and AED actions. Improving public knowledge would help improve the public\'s confidence of intervening during an OHCA and may improve OHCA survival.

OBJECTIVE: We sought to evaluate the impact of a medical directive allowing nurses to use defibrillators in automated external defibrillator-mode (AED) on in-hospital cardiac arrest (IHCA) outcomes.
METHODS: We completed a health record review of consecutive IHCA for which resuscitation was attempted using a pragmatic multi-phase before-after cohort design. We report Utstein outcomes before (Jan.2012-Aug.2013;Control) the implementation of the AED medical directive following usual practice (Sept.2013-Aug.2016;Phase 1), and following the addition of a theory-based educational video (Sept.2016-Dec.2017;Phase 2).
RESULTS: There were 753 IHCA with the following characteristics (Before n = 195; Phase 1n = 372; Phase 2n = 186): mean age 66, 60.0% male, 79.3% witnessed, 29.1% noncardiac-monitored medical ward, 23.9% cardiac cause, and initial ventricular fibrillation/tachycardia (VF/VT) 27.2%. Comparing the Before, Phase 1 and 2: an AED was used 0 time (0.0%), 21 times (5.7%), 15 times (8.1%); mean times to 1st analysis were 7 min, 3 min and 1 min (p < 0.0001); mean times to 1st shock were 12 min, 10 min and 8 min (p = 0.32); return of spontaneous circulation (ROSC) was 63.6%, 59.4% and 58.1% (p = 0.77); survival was 24.6%, 21.0% and 25.8% (p = 0.37). Among IHCA in VF/VT (n = 165), time to 1st analysis and 1st shock decreased by 5 min (p = 0.01) and 6 min (p = 0.23), and ROSC and survival increased by 3.0% (p = 0.80) and 15.6% (p = 0.31). There was no survival benefit overall (1.2%; p = 0.37) or within noncardiac-monitored areas (-7.2%; p = 0.24).
CONCLUSIONS: The implementation of a medical directive allowing for AED use by nurses successfully improved key outcomes for IHCA victims, particularly following the theory-based education video and among the VF/VT group.

UNASSIGNED: The 2021 European Resuscitation Council (ERC) guidelines recommend two automated external defibrillators (AEDs)/km2 and at least 10 first responders/km2. We examined 1) access to AEDs and volunteer first responders in line with these guidelines and 2) its associations with socioeconomic factors and income inequality, focusing on small spatial scales.
UNASSIGNED: We considered data on 776 AEDs in February 2022 and 1,173 out-of-hospital cardiac arrests (OHCAs) including 713 OHCA with app-alerted volunteer first responders from February to September 2022 in Berlin. We fit multilevel models to analyse AED area coverage and Poisson models to examine first responder availability across 12 districts and 536 neighbourhoods.
UNASSIGNED: Median AED area coverage according to the 2021 ERC guidelines was 43.1% (interquartile range (IQR) 2.3-87.2) at the neighbourhood level and median number of available first responders per OHCA case was one (IQR 0.0-1.0). AED area coverage showed a positive association with average income tax per capita, with better coverage in the highest compared to the lowest quartile neighbourhoods (coefficient: 0.13, 95% confidence interval (CI): 0.01-0.25). First responder availability was not associated with income tax. AED area coverage and first responder availability were positively associated with income inequality, with better coverage (coefficient: 0.13, 95% CI: 0.04-0.23) and availability (rate ratio: 1.31, 95% CI: 1.03-1.67) in quartiles of highest as compared to lowest inequality.
UNASSIGNED: Access to resuscitation resources is neither equitable nor in accordance with the 2021 ERC guidelines. Ensuring better access necessitates understanding of socioeconomic factors and income inequality at small spatial scales.

Sudden death resulting from cardiorespiratory arrest carries a high mortality rate and frequently occurs out of hospital. Immediate initiation of cardiopulmonary resuscitation (CPR) by witnesses, combined with automated external defibrillator (AED) use, has proven to double survival rates. Recognising the challenges of timely emergency services in rural areas, the implementation of basic CPR training programmes can improve survival outcomes. This study aims to evaluate the effectiveness of online CPR-AED training among residents in a rural area of Tarragona, Spain.
Quasi-experimental design, comprising two phases. Phase 1 involves assessing the effectiveness of online CPR-AED training in terms of knowledge acquisition. Phase 2 focuses on evaluating participant proficiency in CPR-AED simulation manoeuvres at 1 and 6 months post training. The main variables include the score difference between pre-training and post-training test (phase 1) and the outcomes of the simulated test (pass/fail; phase 2). Continuous variables will be compared using Student\'s t-test or Mann-Whitney U test, depending on normality. Pearson\'s χ2 test will be applied for categorical variables. A multivariate analysis will be conducted to identify independent factors influencing the main variable.
This study adheres to the tenets outlined in the Declaration of Helsinki and of Good Clinical Practice. It operated within the Smartwatch project, approved by the Clinical Research Ethics Committee of the Primary Care Research Institute IDIAP Jordi Gol i Gurina Foundation, code 23/081-P. Data confidentiality aligns with Spanish and European Commission laws for the protection of personal data. The study\'s findings will be published in peer-reviewed journals and presented at scientific meetings.
NCT05747495.

UNASSIGNED: Human exposure to high-altitude and/or low-temperature areas is increasing and cardiac arrest in these circumstances represents an increasing proportion of all treated cardiac arrests. However, little is known about the performance of automated external defibrillators (AED) in these circumstances. The objective of this study is to assess the functional and electrical features of 6 commercially available AEDs in extreme environments.
UNASSIGNED: Accuracy of shockable rhythm detection, the time required for self-test, rhythm analysis, and capacitor charging, together with total energy, peak voltage, peak current, and phasic duration of defibrillation waveform measured after placing the AEDs in simulated high-altitude, simulated low-temperature, and natural composite high-altitude and low-temperature environment for 30 min, were compared to those measured in the standard environment.
UNASSIGNED: All of the shockable rhythms were correctly detected and all of the defibrillation shocks were successfully delivered by the AEDs. However, the time required for self-test, rhythm detection, and capacitor charging was shortened by 1.2% (3 AEDs, maximum 12.4%) in the simulated high-altitude environment, was prolonged by 3.6% (4 AEDs, maximum 40.8%) in the simulated low-temperature environment, and was prolonged by 4.1% (5 AEDs, maximum 52.1%) in the natural environment. Additionally, the total delivered energy was decreased by 2.5% (2 AEDs, maximum 6.8%) in the natural environment.
UNASSIGNED: All of the investigated AEDs functioned properly in simulated and natural environments, but a large variation in the functional and electrical feature change was observed. When performing cardiopulmonary resuscitation in extreme environments, the impact of environmental factors may need consideration.