Use of automated external defibrillator by first responders in out of hospital cardiac arrest: prospective controlled trial

Community First Responders' role in the current and future rural health and care workforce: a mixed-methods study

Background

Community First Responders are trained volunteers dispatched by ambulance services to potentially life-threatening emergencies such as cardiac arrest in the first vital minutes to provide care until highly skilled ambulance staff arrive. Community First Responder schemes were first introduced to support ambulance services in rural communities, where access to prehospital emergency care is more likely to be delayed. Evidence is lacking on their contribution to rural healthcare provision, how care is provided and how this might be improved.

Objectives

We aimed to describe Community First Responder activities, organisation, costs of provision and outcomes of care together with perceptions and views of patients, public, Community First Responders, ambulance service staff and commissioners of their current and future role including innovations in the rural health and care workforce.

Design

We used a mixed-methods design, using a lens of pragmatism and the 'actor', 'behaviour change' and 'causal pathway' framework to integrate quantitative routine and qualitative (policy, guideline and protocol documents with stakeholder interview) data from 6 of 10 English ambulance services. We identified potential innovations in Community First Responder provision and prioritised these using a modified nominal group technique. Patients and public were involved throughout the study.

Results

In 4.5 million incidents from six English regional ambulance services during 2019, pre COVID-19 pandemic, Community First Responders attended first a higher proportion of calls in rural areas (almost 4% of calls) than in urban areas (around 1.5%). They were significantly more likely to be called out to rural (vs. urban) areas and to attend older (vs. younger), white (vs. minority ethnic) people in more affluent (vs. deprived) areas with cardiorespiratory and neurological (vs. other emergency) conditions for higher-priority emergency or urgent (category 1 and 2 compared with category 3, 4 or 5) calls but did also attend lower-category calls for conditions such as falls. We examined 10 documents from seven ambulance services. Ambulance policies and protocols integrated Community First Responders into ambulance service structures to achieve the safe and effective operation of volunteers. Costs, mainly for training, equipment and support, varied widely but were not always clearly delineated. Community First Responders enabled a faster prehospital response time. There was no clear benefit in out-of-hospital cardiac arrest outcomes. A specific Community First Responder falls response reduced ambulance attendances and was potentially cost saving. We conducted semistructured interviews with 47 different stakeholders engaged in Community First Responder functions. This showed the trajectory of becoming a Community First Responder, the Community First Responder role, governance and practice, and the positive views of Community First Responders from stakeholders despite public lack of understanding of their role. Community First Responders' scope of practice varied between ambulance services and had developed into new areas. Innovations prioritised at the consensus workshop were changes in processes and structures and an expanded scope of practice supported by training, which included counselling, peer support, better communication with the control room, navigation and communication technology, and specific mandatory and standardised training for Community First Responders.

Limitations

Missing data and small numbers of interviews in some stakeholder groups (patients, commissioners) are sources of bias.

Future research

Future research should include a robust evaluation of innovations involving Community First Responders.

Trial registration

This trial is registered as ClinicalTrials.gov, NCT04279262.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: NIHR127920) and is published in full in Health and Social Care Delivery Research; Vol. 12, No. 18. See the NIHR Funding and Awards website for further award information.

Prehospital optimal shock energy for defibrillation (POSED): A cluster randomised controlled feasibility trial

Background

We explored the feasibility of a large-scale UK ambulance services trial of optimal defibrillation shock energy for out-of-hospital cardiac arrest. The primary objective of this feasibility study was to establish the number of eligible patients and the number recruited. Secondary outcomes were adherence to allocated treatment and data completeness.

Methods

We conducted a three-arm parallel group cluster randomised controlled feasibility study in a single ambulance service in southern England. Adult patients in out-of-hospital cardiac arrest treated for a shockable rhythm were included. Zoll X series defibrillators (clusters) were randomised to deliver 120-150-200 J, 150-200-200 J, or 200-200-200 J shock strategies.

Results

Between March 2022 and February 2023, we randomised 38 eligible patients (120-150-200 J (n = 12), 150-200-200 J (n = 10), 200-200-200 J (n = 16)) to the study. The recruitment rate per cluster was 0.07 per month. The median patient age was 71 years (IQR 59-81 years); 79% were male. Twenty-eight cardiac arrests (74%) occurred in a private residence, 29 (76%) were witnessed and 32 (84%) patients received bystander CPR. Treatment adherence was 93% and completeness of clinical and electrical outcomes was 86%. At 30 days, 3/36 (8.3%) patients survived; we were unable to collect survival outcomes for two patients. Defibrillation data collection became difficult when defibrillators became separated from their allocated vehicles.

Conclusion

We have demonstrated the feasibility of a cluster randomised controlled trial of optimal shock energy for defibrillation in a UK ambulance service. We have identified possible solutions to issues relating to trial design.

Out-of-hospital cardiac arrest outcomes when law enforcement arrives before emergency medical services

BACKGROUND

Law enforcement (LE) professionals are often dispatched to out-of-hospital cardiac arrests (OHCA) to provide early cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) application with mixed evidence of a survival benefit. Our objective was to comprehensively evaluate LE care in OHCA.

METHODS

This is a secondary analysis of adults with non-traumatic OHCA not witnessed by EMS and without bystander AED use from 2018-2021. Our primary outcome was survival with Cerebral Perfusion Category score ≤ 2 (functional survival). Our exposures included: LE On-scene Only (without providing care); LE CPR Only (without applying an AED); LE Ideal Care (ensuring CPR and AED application). Our control group had no LE arrival before EMS. We performed multivariable logistic regression analyses adjusting for confounders and stratified our analyses by patients with and without bystander CPR.

RESULTS

There were 2569 adult, non-traumatic OHCAs from 2018-2021 meeting inclusion criteria. There were no differences in the odds of functional survival for LE On-scene Only (adjusted odds ratio [95% CI]: 1.28 [0.47-3.45]), LE CPR Only (1.26 [0.80-1.99]), or LE Ideal Care (1.36 [0.79-2.33]). In patients without bystander CPR, LE Ideal Care had significantly higher odds of functional survival (2.01 [1.06-3.81]) compared to no LE on-scene, with no significant associations for LE On-scene Only or LE CPR Only. There were no significant differences by LE care in patients already receiving bystander CPR.

CONCLUSIONS

LE arrival before EMS and ensuring both CPR and AED application is associated with significantly improved functional survival in OHCA patients not already receiving bystander CPR.

Automated external defibrillators and the link to first responder systems

PURPOSE OF REVIEW

Automated external defibrillators are a very effective treatment to convert ventricular fibrillation (VF) in out-of-hospital cardiac arrest. The purpose of this paper is to review recent publications related to automated external defibrillators (AEDs).

RECENT FINDINGS

Much of the recent research focus on ways to utilize publicly available AEDs included in different national/regional registers. More and more research present positive associations between engaging volunteers to increase the use of AEDs. There are only a few recent studies focusing on professional first responders such as fire fighters/police with mixed results. The use of unmanned aerial vehicles (drones) lacks clinical data and is therefore difficult to evaluate. On-site use of AED shows high survival rates but suffers from low incidence of out-of-hospital cardiac arrest (OHCA).

SUMMARY

The use of public AEDs in OHCA are still low. Systems focusing on engaging volunteers in the cardiac arrest response have shown to be associated with higher AED usage. Dispatching drones equipped with AEDs is promising, but research lacks clinical data. On-site defibrillation is associated with high survival rates but is not available for most cardiac arrests.

Police as first reponders improve out-of-hospital cardiac arrest survival

BACKGROUND

Police forces are abundant circulating and might arrive before the emergency services to Out-of-Hospital-Cardiac-Arrest victims. If properly trained, they can provide basic life support and early defibrillation within minutes, probably increasing the survival of the victims. We evaluated the impact of local police as first responders on the survival rates of out-of-hospital cardiac arrest victims in Navarra, Spain, over 7 years.

METHODS

A retrospective analysis of an ongoing Out-of-Hospital Cardiac registry to compare the characteristics and survival of Out-of-Hospital-Cardiac-Arrest victims attended to in first place by local police, other first responders, and emergency ambulance services between 2014 and 2020.

RESULTS

Of 628 cases, 73.7% were men (aged 68.9 ± 15.8), and 26.3% were women (aged 65,0 ± 14,7 years, p < 0.01). Overall survival of patients attended to by police in the first place was 17.8%, other first responders 17.4% and emergency services 13.5% with no significant differences (p > 0.1). Time to initiating cardiopulmonary resuscitation is significant for survival. When police arrived first and started CPR before the emergency services, they arrived at a mean of 5.4 ± 3 min earlier (SD = 3.10). This early police intervention showed an increase in the probability of survival by 10.1%.

CONCLUSIONS

The privileged location and the sole amount of personnel of local police forces trained in life support and their fast delivery of defibrillators as first responders can improve the survival of out-of-hospital cardiac arrest victims.

Differences in Automated External Defibrillator Types in Out-of-Hospital Cardiac Arrest Treated by Police First Responders

Background: Police first responder systems also including automated external defibrillation (AED) has in the past shown considerable impact on favourable outcomes after out-of-hospital cardiac arrest (OHCA). While short hands-off times in chest compressions are known to be beneficial, various AED models use different algorithms, inducing longer or shorter durations of crucial timeframes along basic life support (BLS). Yet, data on details of these differences, and also of their potential impact on clinical outcomes are scarce. Methods: For this retrospective observational study, patients with OHCA of presumed cardiac origin and initially shockable rhythm treated by police first responders in Vienna, Austria, between 01/2013 and 12/2021 were included. Data from the Viennese Cardiac Arrest Registry and AED files were extracted, and exact timeframes were analyzed. Results: There were no significant differences in the 350 eligible cases in demographics, return of spontaneous circulation, 30-day survival, or favourable neurological outcome between the used AED types. However, the Philips HS1 and -FrX AEDs showed immediate rhythm analysis after electrode placement (0 [0-1] s) and almost no shock loading time (0 [0-1] s), as opposed to the LP CR Plus (3 [0-4] and 6 [6-6] s, respectively) and LP 1000 (3 [2-10] and 6 [5-7] s, respectively). On the other hand, the HS1 and -FrX had longer analysis times of 12 [12-16] and 12 [11-18] s than the LP CR Plus (5 [5-6] s) and LP 1000 (6 [5-8] s). The duration from when the AED was turned on until the first defibrillation were 45 [28-61] s (Philips FrX), 59 [28-81] s (LP 1000), 59 [50-97] s (HS1), and 69 [55-85] s (LP CR Plus). Conclusion: In a retrospective analysis of OHCA-cases treated by police first responders, we could not find significant differences in clinical patient outcomes concerning the respective used AED model. However, various differences in time durations (e.g., electrode placement to rhythm analysis, analysis duration, or AED turned on until first defibrillation) along the BLS algorithm were seen. This opens up the question of AED-adaptations and tailored training methods for professional first responders.

Public access defibrillation: challenges and new solutions

PURPOSE OF REVIEW

The purpose of this article is to review the current status of public access defibrillation and the various utility modalities of early defibrillation.

RECENT FINDINGS

Defibrillation with on-site automated external defibrillators (AEDs) has been the conventional approach for public access defibrillation. This strategy is highly effective in cardiac arrests occurring in close proximity to on-site AEDs; however, only a few cardiac arrests will be covered by this strategy. During the last decades, additional strategies for public access defibrillation have developed, including volunteer responder programmes and drone assisted AED-delivery. These programs have increased chances of early defibrillation within a greater radius, which remains an important factor for survival after out-of-hospital cardiac arrest.

SUMMARY

Recent advances in the use of public access defibrillation show great potential for optimizing early defibrillation. With new technological solutions, AEDs can be transported to the cardiac arrest location reaching OHCAs in both public and private locations. Furthermore, new technological innovations could potentially identify and automatically alert the emergency medical services in nonwitnessed OHCA previously left untreated.

Are first responders first? The rally to the suspected out-of-hospital cardiac arrest

BACKGROUND

Time is the crucial factor in the "chain of survival" treatment concept for out-of-hospital cardiac arrest (OHCA). We aimed to measure different response time intervals by comparing emergency medical system (EMS), fire fighters and smartphone aided volunteer responders.

METHODS

In two large Swedish regions, volunteer responders were timed from the alert until they arrived at the scene of the suspected OHCA. The first arriving volunteer responders who tried to fetch an automated external defibrillator (AED-responder) and who ran to perform bystander cardiopulmonary resuscitation (CPR-responder) were compared to both the first arriving EMS and fire fighters. Three-time intervals were measured, from call to dispatch, the unit response time (from dispatch to arrival) and the total response time.

RESULTS

During 22 months, 2631 suspected OHCAs were included. The median time from call to dispatch was in minutes 1.8 (95% CI = 1.7-1.8) for EMS, 2.9 (95% CI = 2.8-3.0) for fire-fighters and 3.0 (95% CI = 2.9-3.1) for volunteer responders. The median unit response time was 8.3 (95% CI = 8.1-8.5) for EMS, 6.8 (95% CI = 6.7-6.9) for fire fighters and 6.0 (95% CI = 5.7-6.2) for AED-responders and 4.6 (95% CI = 4.5-4.8) for CPR-responders. The total response time was 10.4 (95% CI = 10.1-10.6) for EMS, 10.2 (95% CI = 9.9-10.4) for fire fighters, 9.6 (95% CI = 9.1-9.8) for AED-responders and 8.2 (95% CI = 8.0-8.3) for CPR-responders.

CONCLUSION

First arriving volunteer responders had the shortest unit response time when compared to both fire fighters and EMS, however this advantage was reduced by delays introduced at the dispatch center. Earlier automatic dispatch should be considered in further studies.

Optimizing Outcomes After Out-of-Hospital Cardiac Arrest With Innovative Approaches to Public-Access Defibrillation: A Scientific Statement From the International Liaison Committee on Resuscitation

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Optimizing outcomes after out-of-hospital cardiac arrest with innovative approaches to public-access defibrillation: A scientific statement from the International Liaison Committee on Resuscitation

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Gazing through time and beyond the health sector: Insights from a system dynamics model of cardiovascular disease in Australia

OBJECTIVE

To construct a whole-of-system model to inform strategies that reduce the burden of cardiovascular disease (CVD) in Australia.

METHODS

A system dynamics model was developed with a multidisciplinary modelling consortium. The model population comprised Australians aged 40 years and over, and the scope encompassed acute and chronic CVD as well as primary and secondary prevention. Health outcomes were CVD-related deaths and hospitalisations, and economic outcomes were the net benefit from both the healthcare system and societal perspectives. The eight strategies broadly included creating social and physical environments supportive of a healthy lifestyle, increasing the use of preventive treatments, and improving systems response to acute CVD events. The effects of strategies were estimated as relative differences to the business-as-usual between 2019-2039. Probabilistic sensitivity analysis produced uncertainty intervals of interquartile ranges (IQR).

FINDINGS

The greatest reduction in CVD-related deaths was seen in strategies that improve systems response to acute CVD events (8.9%, IQR: 7.7-10.2%), yet they resulted in an increase in CVD-related hospitalisations due to future recurrent admissions (1.6%, IQR: 0.1-2.3%). This flow-on effect highlighted the importance of addressing underlying CVD risks. On the other hand, strategies targeting the broad environment that supports a healthy lifestyle were effective in reducing both hospitalisations (7.1%; IQR: 5.0-9.5%) and deaths (8.1% reduction; IQR: 7.1-8.9%). They also produced an economic net benefit of AU$43.3 billion (IQR: 37.7-48.7) using a societal perspective, largely driven by productivity gains. Overall, strategic planning to reduce the burden of CVD should consider the varying effects of strategies over time and beyond the health sector.

A review on initiatives for the management of daily medical emergencies prior to the arrival of emergency medical services

Emergency services worldwide face increasing cost pressure that potentially limits their existing resources. In many countries, emergency services also face the issues of staff shortage-creating extra challenges and constraints, especially during crisis times such as the COVID-19 pandemic-as well as long distances to sparsely populated areas resulting in longer response times. To overcome these issues and potentially reduce consequences of daily (medical) emergencies, several countries, such as Sweden, Germany, and the Netherlands, have started initiatives using new types of human resources as well as equipment, which have not been part of the existing emergency systems before. These resources are employed in response to medical emergency cases if they can arrive earlier than emergency medical services (EMS). A good number of studies have investigated the use of these new types of resources in EMS systems, from medical, technical, and logistical perspectives as their study domains. Several review papers in the literature exist that focus on one or several of these new types of resources. However, to the best of our knowledge, no review paper that comprehensively considers all new types of resources in emergency medical response systems exists. We try to fill this gap by presenting a broad literature review of the studies focused on the different new types of resources, which are used prior to the arrival of EMS. Our objective is to present an application-based and methodological overview of these papers, to provide insights to this important field and to bring it to the attention of researchers as well as emergency managers and administrators.

Stress hormones kinetics in ventricular fibrillation cardiac arrest and resuscitation: Translational and therapeutic implications

BACKGROUND

Knowing the kinetics of endogenous stress hormones during cardiac arrest and cardiopulmonary resuscitation (CRP) will help to optimize personalized physiology-guided treatment. The aim of this study was to examine the dynamic changes in stress hormones in a swine model of ventricular fibrillation (VF) cardiac arrest.

METHODS

Ventricular fibrillation was induced in 10 healthy Landrace/Large White piglets, which were subsequently left untreated for 8 min. All animals were resuscitated according to the 2015 European Resuscitation Council guidelines. The concentration of adrenalin, noradrenalin, and cortisol was measured at baseline and at the 4th and 8th minute of VF-cardiac arrest, as well as at 30-min, 60-min, 24 h and 48 h post-ROSC.

RESULTS

By the end of the 4th min of VF, the animals of the ROSC group exhibited significantly higher adrenaline levels compared to those of the no-ROSC group (7264 pg/ml vs. 1648 pg/ml, p = 0.03). Noradrenaline was higher in the ROSC group at the 4th min of VF (3021 pg/ml vs. 1626 pg/ml, p = 0.02). Cortisol levels in the ROSC group were significantly lower by the end of the 8th min of VF [16.25 ng/ml vs. 92.82 ng/ml, p = 0.03]. With a cut-off point of 5970 pg/ml, adrenaline at the 4th min of VF exhibited 100% sensitivity and 80% specificity for predicting ROSC.

CONCLUSION

Higher endogenous adrenaline and lower endogenous cortisol levels were associated with ROSC.

General practice and cardiac arrest community first response in Ireland

Background

In Ireland, the MERIT 3 scheme enables doctors to volunteer as cardiac arrest community first responders and receive text message alerts from emergency medical services (EMS) to facilitate early care.

Aim

To establish the sustainability, systems and clinical outcomes of a novel, general practice based, cardiac arrest first response initiative over a four-year period.

Methods

Data on alerts, responses, incidents and outcomes were gathered prospectively using EMS control data, incident data reported by responders and corroborative data from the national Out-of-Hospital Cardiac Arrest Registry.

Results

Over the period 2016–2019, 196 doctors joined MERIT 3 and 163 (83.2%) were alerted on one or more occasions; 61.3% of those alerted responded to at least one alert. Volunteer doctors attended 300 patients of which 184 (61.3%) had suffered OHCA and had a resuscitation attempt. Responders arrived to OHCA before EMS on 75 occasions (40.8%), initiated chest compressions on seven occasions (3.8%), and brought the first defibrillator on 42 occasions (22.8%). Information on the first monitored rhythm was available for 149/184 (81.0%) patients and was shockable in 30/149 (20.1%); in 9/30 cases, shocks were administered by responders. The overall survival rate was 11.0% (national survival rate 7.3%). Doctors also provided advanced life support and were closely involved in decision making on ceasing resuscitation.

Conclusion

The MERIT 3 initiative in Ireland has been sustained over a four-year period and has demonstrated the ability of volunteer doctors to provide early care for OHCA patients as well as more complex interventions including end-of-life care. Further development of this strategy is warranted.

European first responder systems and differences in return of spontaneous circulation and survival after out-of-hospital cardiac arrest: A study of registry cohorts

BACKGROUND

In Europe, survival-rates after out-of-hospital cardiac arrest (OHCA) vary widely between regions. Whether a system dispatching First Responders (FRs; main FR-types: firefighters, police officers, citizen-responders) is present or not may be associated with survival-rates. This study aimed to assess the association between having a dispatched FR-system and rates of return of spontaneous circulation (ROSC) and survival across Europe.

METHODS

Results of an inventory of dispatched FR-systems for OHCA in Europe were combined with aggregate ROSC and survival data from the EuReCa-TWO study and additionally collected data. Regression analysis (weighted on number of patients included per region) was performed to study the association between having a dispatched FR-system and ROSC and survival-rates to hospital discharge in the total population and in patients with shockable initial rhythm, witnessed OHCA and bystander cardiopulmonary resuscitation (CPR; Utstein comparator group). For regions without a dispatched FR-system, the theoretical survival-rate if a dispatched FR-system would have existed was estimated.

FINDINGS

We included 27 European regions. There were 15,859 OHCAs in the total group and 2,326 OHCAs in the Utstein comparator group. Aggregate ROSC and survival-rates were significantly higher in regions with an FR-system compared to regions without (ROSC: 36% [95%CI 35%-37%] vs. 24% [95%CI 23%-25%]; P<0.001; survival in total population [N=15.859]: 13% [95%CI 12%-15%] vs. 5% [95%CI 4%-6%]; P<0.001; survival in Utstein comparator group [N=2326]: 33% [95%CI 30%-36%] vs. 18% [95%CI 16%-20%]; P<0.001), and in regions with more than one FR-type compared to regions with only one FR-type. All main FR-types were associated with higher survival-rates (all P<0.050).

INTERPRETATION

European regions with dispatched FRs showed higher ROSC and survival-rates than regions without.

FUNDING

This project/work has received funding from the European Union's Horizon 2020 research and innovation programme under acronym ESCAPE-NET, registered under grant agreement No 733381 (IO, HLT and MTB) and the European Union's COST programme under acronym PARQ, registered under grant agreement No CA19137 (IO, DC, HLT, MTB). HLT and MTB were supported by a grant from the Netherlands CardioVascular Research Initiative, Dutch Heart Foundation, Dutch Federation of University Medical Centres, Netherlands Organization for Health Research and Development, Royal Netherlands Academy of Sciences - CVON2017-15 RESCUED (HLT), and CVON2018-30 Predict2 (HLT and MTB).

Cost-effectiveness of a novel smartphone application to mobilize first responders after witnessed OHCA in Belgium

Background

EVapp (Emergency Volunteer Application) is a Belgian smartphone application that mobilizes volunteers to perform cardiopulmonary resuscitation (CPR) and defibrillation with publicly available automatic external defibrillators (AED) after an emergency call for suspected out of hospital cardiac arrest (OHCA). The aim is to bridge the time before the arrival of the emergency services.

Methods

An accessible model was developed, using literature data, to simulate survival and cost-effectiveness of nation-wide EVapp implementation. Initial validation was performed using field data from a first pilot study of EVapp implementation in a city in Flanders, covering 2.5 years of implementation.

Results

Simulation of nation-wide EVapp implementation resulted in an additional yearly 910 QALY gained over the current baseline case scenario (worst case 632; best case 3204). The cost per QALY associated with EVapp implementation was comparable to the baseline scenario, i.e., 17 vs 18 k€ QALY⁻¹.

Conclusions

EVapp implementation was associated with a positive balance on amount of QALY gained and cost of QALY. This was a consequence of both the lower healthcare costs for patients with good neurological outcome and the more efficient use of yet available resources, which did not outweigh the costs of operation.

Effectiveness of the Dual Dispatch to Cardiac Arrest Policy in Houston, Texas

CONTEXT

Houston policy is to dual dispatch medically trained firefighters, in addition to emergency medical services (EMS) units to out-of-hospital cardiac arrest (OHCA) cases. While believed to improve public health outcomes, no research exists supporting the policy that when firefighters respond before a better-equipped EMS unit, they increase the probability of survival.

OBJECTIVE

To inform EMS policy decisions regarding the effectiveness of dual dispatch by determining the impact of medically trained firefighter dispatch on return of spontaneous circulation (ROSC), a measure of survivability, in OHCA 911 calls while controlling for the subsequent arrival of an EMS unit.

DESIGN

This retrospective study uses logistic regression to determine the association between ROSC and response time for fire apparatus first responders controlling for arrival of the EMS unit.

SETTING

Out-of-hospital cardiac arrest cases in Houston between May 2008 and April 2013 when dual dispatch was used.

PARTICIPANTS

A total of 6961 OHCA cases with the complete data needed for the analysis.

MAIN OUTCOME MEASURES

Logistic regression of the dependence of OHCA survival using the indicator ROSC, as related to the fire first responder response times controlling for subsequent arrival of the EMS.

RESULTS

Fire apparatus arrived first in 46.7% of cases, a median value of 1.5 minutes before an EMS unit. Controlling for subsequent arrival time of EMS has no effect on ROSC achieved by the fire first responder. If the firefighters had not responded, the resulting 1.5-minute increase in response time equates to a decrease in probability of attaining ROSC of 20.1% for cases regardless of presenting heart rhythm and a 47.7% decrease for ventricular fibrillation cases in which bystander cardiopulmonary resuscitation was initiated.

CONCLUSIONS

The firefighter first responder not only improved response time but also greatly increased survivability independent of the arrival time of the better-equipped EMS unit, validating the public health benefit of the dual dispatch policy in Houston.

Providing the best chest compression quality: Standard CPR versus chest compressions only in a bystander resuscitation model

AIM OF THE STUDY

Bystander-initiated basic life support (BLS) for the treatment of prehospital cardiac arrest increases survival but is frequently not performed due to fear and a lack of knowledge. A simple flowchart can improve motivation and the quality of performance. Furthermore, guidelines do recommend a chest compression (CC)-only algorithm for dispatcher-assisted bystander resuscitation, which may lead to increased fatigue and a loss of compression depth. Consequently, we wanted to test the hypothesis that CCs are more correctly delivered in a flowchart-assisted standard resuscitation algorithm than in a CC-only algorithm.

METHODS

With the use of a manikin model, 84 laypersons were randomized to perform either flowchart-assisted standard resuscitation or CC-only resuscitation for 5min. The primary outcome was the total number of CCs.

RESULTS

The total number of correct CCs did not significantly differ between the CC-only group and the standard group (63 [±81] vs. 79 [±86]; p = 0.394; 95% CI of difference: 21-53). The total hand-off time was significantly lower in the CC-only group than in the standard BLS group. The relative number of correct CCs (the fraction of the total number of CCs achieving 5-6cm) and the level of exhaustion after BLS did not significantly differ between the groups.

CONCLUSION

Standard BLS did not lead to an increase in correctly delivered CCs compared to CC-only resuscitation and exhibited significantly more hand-off time. The low rate of CCs in both groups indicates the need for an increased focus on performance during BLS training.

AED and text message responders density in residential areas for rapid response in out-of-hospital cardiac arrest

BACKGROUND

For out-of-hospital cardiac arrest (OHCA) in residential areas, a dispatcher driven alert-system using text messages (TM-system) directing local rescuers (TM-responders) to OHCA patients was implemented and the desired density of automated external defibrillators (AEDs) or TM-responders investigated.

METHODS

We included OHCA cases with the TM-system activated in residential areas between 2010-2017. For each case, densities/km² of activated AEDs and TM-responders within a 1000 m circle were calculated. Time intervals between 112-call and first defibrillation were calculated.

RESULTS

In total, 813 patients (45%) had a shockable initial rhythm. In 17% a TM-system AED delivered the first shock. With increasing AED density, the median time to shock decreased from 10:59 to 08:17 min. (p < 0.001) and shocks <6 min increased from 6% to 12% (p = 0.024). Increasing density of TM-responders was associated with a decrease in median time to shock from 10:59 to 08:20 min. (p < 0.001) and increase of shocks <6 min from 6% to 13% (p = 0.005). Increasing density of AEDs and TM-responders resulted in a decline of ambulance first defibrillation by 19% (p = 0.016) and 22% (p = 0.001), respectively. First responder AED defibrillation did not change significantly. Densities of >2 AEDs/km² did not result in further decrease of time to first shock but >10 TM-responders/km² resulted in more defibrillations <6 min.

CONCLUSION

With increasing AED and TM-responder density within a TM-system, time to defibrillation in residential areas decreased. AED and TM-responders only competed with ambulances, not with first responders. The recommended density of AEDs and TM-responders for earliest defibrillation is 2 AEDs/km² and >10 TM-responders/km².

Community first responders for out-of-hospital cardiac arrest in adults and children

BACKGROUND

Mobilization of community first responders (CFRs) to the scene of an out-of-hospital cardiac arrest (OHCA) event has been proposed as a means of shortening the interval from occurrence of cardiac arrest to performance of cardiopulmonary resuscitation (CPR) and defibrillation, thereby increasing patient survival.

OBJECTIVES

To assess the effect of mobilizing community first responders (CFRs) to out-of-hospital cardiac arrest events in adults and children older than four weeks of age, in terms of survival and neurological function.

SEARCH METHODS

We searched the following databases for relevant trials in January 2019: CENTRAL, MEDLINE (Ovid SP), Embase (Ovid SP), and Web of Science. We also searched the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov, and we scanned the abstracts of conference proceedings of the American Heart Association and the European Resuscitation Council.

SELECTION CRITERIA

We included randomized and quasi-randomized trials (RCTs and q-RCTs) that compared routine emergency medical services (EMS) care versus EMS care plus mobilization of CFRs in instances of OHCA.Trials with randomization by cluster were eligible for inclusion, including cluster-design studies with intervention cross-over.In some communities, the statutory ambulance service/EMS is routinely provided by the local fire service. For the purposes of this review, this group represents the statutory ambulance service/EMS, as distinct from CFRs, and was not included as an eligible intervention.We did not include studies primarily focused on opportunistic bystanders. Individuals who were present at the scene of an OHCA event and who performed CPR according to telephone instruction provided by EMS call takers were not considered to be CFRs.Studies primarily assessing the impact of specific additional interventions such as administration of naloxone in narcotic overdose or adrenaline in anaphylaxis were also excluded.We included adults and children older than four weeks of age who had experienced an OHCA.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed all titles and abstracts received to assess potential eligibility, using set inclusion criteria. We obtained and examined in detail full-text copies of all papers considered potentially eligible, and we approached authors of trials for additional information when necessary. We summarized the process of study selection in a PRISMA flowchart.Three review authors independently extracted relevant data using a standard data extraction form and assessed the validity of each included trial using the Cochrane 'Risk of bias' tool. We resolved disagreements by discussion and consensus.We synthesized findings in narrative fashion due to the heterogeneity of the included studies. We used the principles of the GRADE system to assess the certainty of the body of evidence associated with specific outcomes and to construct a 'Summary of findings' table.

MAIN RESULTS

We found two completed studies involving a total of 1136 participants that ultimately met our inclusion criteria. We also found one ongoing study and one planned study. We noted significant heterogeneity in the characteristics of interventions and outcomes measured or reported across these studies, thus we could not pool study results.One completed study considered the dispatch of police and fire service CFRs equipped with automatic external defibrillators (AEDs) in an EMS system in Amsterdam and surrounding areas. This study was an RCT with allocation made by cluster according to non-overlapping geographical regions. It was conducted between 5 January 2000 and 5 January 2002. All participants were 18 years of age or older and had experienced witnessed OHCA. The study found no difference in survival at hospital discharge (odds ratio (OR) 1.3, 95% confidence interval (CI) 0.8 to 2.2; 1 RCT; 469 participants; low-certainty evidence), despite the observation that all 72 incidences of defibrillation performed before EMS arrival occurred in the intervention group (OR and 95% CI - not applicable; 1 RCT; 469 participants; moderate-certainty evidence). This study reported increased survival to hospital admission in the intervention group (OR 1.5, 95% CI 1.1 to 2.0; 1 RCT; 469 participants; moderate-certainty evidence).The second completed study considered the dispatch of nearby lay volunteers in Stockholm, Sweden, who were trained to perform cardiopulmonary resuscitation (CPR). This represented a supplementary CFR intervention in an EMS system where police and fire services were already routinely dispatched to OHCA in addition to EMS ambulances. This study, an RCT, included both witnessed and unwitnessed OHCA and was conducted between 1 April 2012 and 1 December 2013. Participants included adults and children eight years of age and older. Researchers found no difference in 30-day survival (OR 1.34, 95% CI 0.79 to 2.29; 1 RCT; 612 participants; low-certainty evidence), despite a significant increase in CPR performed before EMS arrival (OR 1.49, 95% CI 1.09 to 2.03; 1 RCT; 665 participants; moderate-certainty evidence).Neither of the included completed studies considered neurological function at hospital discharge or at 30 days, measured by cerebral performance category or by any other means. Neither of the included completed studies considered health-related quality of life. The overall certainty of evidence for the outcomes of included studies was low to moderate.

AUTHORS' CONCLUSIONS

Moderate-certainty evidence shows that context-specific CFR interventions result in increased rates of CPR or defibrillation performed before EMS arrival. It remains uncertain whether this can translate to significantly increased rates of overall patient survival. When possible, further high-quality RCTs that are adequately powered to measure changes in survival should be conducted.The included studies did not consider survival with good neurological function. This outcome is likely to be important to patients and should be included routinely wherever survival is measured.We identified one ongoing study and one planned trial whose results once available may change the results of this review. As this review was limited to randomized and quasi-randomized trials, we may have missed some important data from other study types.

An analysis of the relationship between the applied medical rescue actions and the return of spontaneous circulation in adults with out-of-hospital sudden cardiac arrest

Sudden cardiac arrest (SCA) is a significant medical and social issue, the main cause of death in Europe and the United States.The aim of the research was to evaluate the effectiveness of emergency medical procedures applied by emergency medical teams in prehospital care in the context of return of spontaneous circulation (ROSC).The case-control study was based on the medical documentation of the Rescue Service in Katowice (responsible for monitoring 2.7 million inhabitants of the region) referring to 2016. The research involved exclusively adults (ie, individuals older than 18 years) with out-of-hospital cardiac arrest (OHCA). After considering the above inclusion criteria, there were 1603 dispatch order forms (0.64% of all dispatch orders) involved in further research.On the basis of the emergency medical procedure forms, the actions of emergency medical teams were verified as medical procedures (endotracheal intubation, the use of suction pumps, defibrillation, the use of alternatives providing airway patency and ROSC was determined.The analysis covered 1603 cases of OHCA. SCA turned out more frequent in men than in women (P = .000). Most often, SCA occurred in domestic conditions during the day and was witnessed by a third person. In 59.9% of the cases, actions were taken by witnesses, which increased the probability of ROSC. Patients were usually intubated (51.4%). Respirators were used less frequently (20.2%). Ventricular fibrillation (VF) was reported only in 22.0% of the cases. The ROSC rate was higher in the group of patients with diagnosed VF than in those with nonshockable rhythms (VF, 55.43% vs asystole, 24.05%; P = .000).Successful resuscitation depends on the quality of emergency medical procedures performed at the place of incident. The highest probability of ROSC is related with defibrillation (in the cases of VF or ventricular tachycardia with no pulse), intubation, the application of a respirator, and performing mechanical ventilation, as well as with a shorter time from dispatch to arrival.

A five-year retrospective study of out-of-hospital cardiac arrest in a north-east Italian urban area

BACKGROUND

The reporting and analysing of data of out-of-hospital cardiac arrests encourages the quality improvement of the emergency medical services. For this reason, the establishment of a sufficiently large patient database is intended to allow analysis of resuscitation treatments for out-of-hospital cardiac arrests and performances of different emergency medical services.

AIMS

The aim of this study was to describe the demographics, characteristics, outcomes and determinant factors of survival for patients who suffered an out-of-hospital cardiac arrest.

METHODS

this was a retrospective study including all out-of-hospital cardiac arrest cases treated by the emergency medical service in the district of Udine (Italy) from 1 January 2010-31 December 2014.

RESULTS

A total of 1105 out-of-hospital cardiac arrest patients were attended by the emergency medical service. Of these, 489 (44.2%) underwent cardiopulmonary resuscitation, and return of spontaneous circulation was achieved in 142 patients (29%). There was a male predominance overall, and the main age was 72.6 years (standard deviation 17.9). Cardiopulmonary resuscitation before emergency medical service arrival was performed on 62 cases (44%) in the return of spontaneous circulation group, and on 115 cases (33%) in the no return of spontaneous circulation group ( p<0.024). Among the 142 cases of return of spontaneous circulation, 29 (5.9%) survived to hospital discharge. There was a smaller likelihood of return of spontaneous circulation when patients were female (odds ratio 0.61, 0.40-0.93). Patients who had an out-of-hospital cardiac arrest with an initial shockable rhythm (odds ratio 6.33, 3.86-10.39) or an age <60 years (odds ratio 2.91, 1.86-4.57) had a greater likelihood of return of spontaneous circulation. In addition, bystander cardiopulmonary resuscitation (odds ratio 1.56, 1.04-2.33) was associated with an increased chance of return of spontaneous circulation.

CONCLUSION

The incidence of out-of-hospital cardiac arrest and survival rate lies within the known range. A wider database is necessary to achieve a better knowledge of out-of-hospital cardiac arrest and to drive future investments in the healthcare system.

Different defibrillation strategies in survivors after out-of-hospital cardiac arrest

BACKGROUND

In the last decade, there has been a rapid increase in the dissemination of automated external defibrillators (AEDs) for prehospital defibrillation of out-of-hospital cardiac arrest patients. The aim of this study was to study the association between different defibrillation strategies on survival rates over time in Copenhagen, Stockholm, Western Sweden and Amsterdam, and the hypothesis was that non-EMS defibrillation increased over time and was associated with increased survival.

METHODS

We performed a retrospective analysis of four prospectively collected cohorts of out-of-hospital cardiac arrest patients between 2008 and 2013. Emergency medical service (EMS)-witnessed arrests were excluded.

RESULTS

A total of 22 453 out-of-hospital cardiac arrest patients with known survival status were identified, of whom 2957 (13%) survived at least 30 days postresuscitation. Of all survivors with a known defibrillation status, 2289 (81%) were defibrillated, 1349 (59%) were defibrillated by EMS, 454 (20%) were defibrillated by a first responder AED and 429 (19%) were defibrillated by an onsite AED and 57 (2%) were unknown. The percentage of survivors defibrillated by first responder AEDs (from 13% in 2008 to 26% in 2013, p<0.001 for trend) and onsite AEDs (from 14% in 2008 to 30% in 2013, p<0.001 for trend) increased. The increased use of these non-EMS AEDs was associated with the increase in survival rate of patients with a shockable initial rhythm.

CONCLUSION

Survivors of out-of-hospital cardiac arrest are increasingly defibrillated by non-EMS AEDs. This increase is primarily due to a large increase in the use of onsite AEDs as well as an increase in first-responder defibrillation over time. Non-EMS defibrillation accounted for at least part of the increase in survival rate of patients with a shockable initial rhythm.

Gender and age-specific aspects of awareness and knowledge in basic life support

Background

The ‘chain of survival’—including early call for help, early cardiopulmonary resuscitation (CPR) and early defibrillation—represents the most beneficial approach for favourable patient outcome after out-of-hospital cardiac arrest (OHCA). Despite increasing numbers of publicly accessible automated external defibrillators (AED) and interventions to increase public awareness for basic life support (BLS), the number of their use in real-life emergency situations remains low.

Methods

In this prospective population-based cross-sectional study, a total of 501 registered inhabitants of Vienna (Austria) were randomly approached via telephone calls between 08/2014 and 09/2014 and invited to answer a standardized questionnaire in order to identify public knowledge and awareness of BLS and AED-use.

Results

We found that more than 52 percent of participants would presume OHCA correctly and would properly initiate BLS attempts. Of alarming importance, only 33 percent reported that they would be willing to perform CPR and 50 percent would use an AED device. There was a significantly lower willingness to initiate BLS attempts (male: 40% vs. female: 25%; OR: 2.03 [95%CI: 1.39–2.98]; p<0.001) and to use an AED device (male: 58% vs. female: 44%; OR: 1.76 [95%CI: 1.26–2.53]; p = 0.002) in questioned female individuals compared to their male counterparts. Interestingly, we observed a strongly decreasing level of knowledge and willingness for BLS attempts (-14%; OR: 0.72 [95%CI: 0.57–0.92]; p = 0.027) and AED-use (-19%; OR: 0.68 [95%CI: 0.54–0.85]; p = 0.001) with increasing age.

Conclusion

We found an overall poor knowledge and awareness concerning BLS and the use of AEDs among the Viennese population. Both female and elderly participants reported the lowest willingness to perform BLS and use an AED in case of OHCA. Specially tailored programs to increase awareness and willingness among both the female and elderly community need to be considered for future educational interventions.

The challenges and possibilities of public access defibrillation

Out-of-hospital cardiac arrest (OHCA) is a major health problem that affects approximately four hundred and thousand patients annually in the United States alone. It is a major challenge for the emergency medical system as decreased survival rates are directly proportional to the time delay from collapse to defibrillation. Historically, defibrillation has only been performed by physicians and in-hospital. With the development of automated external defibrillators (AEDs), rapid defibrillation by nonmedical professionals and subsequently by trained or untrained lay bystanders has become possible. Much hope has been put to the concept of Public Access Defibrillation with a massive dissemination of public available AEDs throughout most Western countries. Accordingly, current guidelines recommend that AEDs should be deployed in places with a high likelihood of OHCA. Despite these efforts, AED use is in most settings anecdotal with little effect on overall OHCA survival. The major reasons for low use of public AEDs are that most OHCAs take place outside high incidence sites of cardiac arrest and that most OHCAs take place in residential settings, currently defined as not suitable for Public Access Defibrillation. However, the use of new technology for identification and recruitment of lay bystanders and nearby AEDs to the scene of the cardiac arrest as well as new methods for strategic AED placement redefines and challenges the current concept and definitions of Public Access Defibrillation. Existing evidence of Public Access Defibrillation and knowledge gaps and future directions to improve outcomes for OHCA are discussed. In addition, a new definition of the different levels of Public Access Defibrillation is offered as well as new strategies for increasing AED use in the society.

Effect of a first responder on survival outcomes after out-of-hospital cardiac arrest occurs during a period of exercise in a public place

INTRODUCTION

The deployment of first responders in a public place is one of the interventions that is used for increasing bystander cardiopulmonary resuscitation (CPR) of out-of-hospital cardiac arrests (OHCA). We studied the association between the presence of a first responder and the survival of OHCA that occurred during a period of exercise in a public place.

METHODS

All of the adult OHCAs of a presumed cardiac etiology that occurred during a period of exercise in a public place and that were witnessed by a bystander between 2013 and 2015 were analyzed. The main exposure of interest was the characteristics of the bystander (first responder vs. layperson). The endpoints were the provision of bystander CPR and good neurological recovery. Multivariable logistic regression analysis, adjusting for patient-environment and prehospital factors, was performed.

RESULTS

A total of 870 patients had a cardiac arrest during a period of exercise in a public place, and 58 (6.7%) patients were witnessed by the first responder. The OHCAs witnessed by first responders were more likely to result in bystander CPR than those witnessed by laypersons (89.7% vs. 75.4%, p = 0.01, adjusted OR (95% CI): 3.51 (1.44-8.55)). In terms of good neurological recovery, the OHCAs witnessed by first responders had a higher likelihood than the patients witnessed by laypersons (37.9% vs, 24.0%, p = 0.02, adjusted OR (95% CI): 2.92 (1.33-6.40)).

CONCLUSION

The OHCAs occurred during a period of exercise in a public place and whom first responders witnessed were more likely to receive bystander CPR and to have a neurologically intact survival.

Bystander automated external defibrillator use and clinical outcomes after out-of-hospital cardiac arrest: A systematic review and meta-analysis

AIM

To systematically review studies comparing bystander automated external defibrillator (AED) use to no AED use in regard to clinical outcomes in out-of-hospital cardiac arrest (OHCA), and to provide a descriptive summary of studies on the cost-effectiveness of bystander AED use.

METHODS

We searched Medline, Embase, the Web of Science, and the Cochrane Library for randomized trials and observational studies published before June 1, 2017. Meta-analyses were performed for patients with all rhythms, shockable rhythms, and non-shockable rhythms.

RESULTS

Forty-four observational studies, 3 randomized trials, and 13 cost-effectiveness studies were included. Meta-analysis of 6 observational studies without critical risk of bias showed that bystander AED use was associated with survival to hospital discharge (all rhythms OR: 1.73 [95%CI: 1.36, 2.18], shockable rhythms OR: 1.66 [95%CI: 1.54, 1.79]) and favorable neurological outcome (all rhythms OR: 2.12 [95%CI: 1.36, 3.29], shockable rhythms OR: 2.37 [95%CI: 1.58, 3.57]). There was no association between bystander AED use and neurological outcome for non-shockable rhythms (OR: 0.76 [95%CI: 0.10, 5.87]). The Public-Access Defibrillation trial found higher survival rates when volunteers were equipped with AEDs. The other trials found no survival difference, although their study settings differed. The quality of evidence was low for randomized trials and very low for observational studies. AEDs were cost-effective in settings with high cardiac arrest incidence, with most studies reporting ratios < $100,000 per quality-adjusted life years.

CONCLUSIONS

The evidence supports the association between bystander AED use and improved clinical outcomes, although the quality of evidence was low to very low.

Effective deployment of public-access automated external defibrillators to improve out-of-hospital cardiac arrest outcomes

Out‐of‐hospital cardiac arrest (OHCA) is a major health concern in Japan and other developed countries with aging populations. Improvements in OHCA outcomes require streamlining the chain of survival. Deployment of public‐access automated external defibrillators (PADs) and defibrillation by bystanders is one strategy that may streamline the chain by reducing the time to defibrillation in individuals with shockable rhythms. Although the effectiveness of PAD programs in increasing survival to discharge has been reported, there have been criticisms and concerns about the small population impact, cost‐effectiveness, and potential negative impact on those with nonshockable rhythms. This article reviews relevant literature regarding the effectiveness and concerns regarding PAD for OHCA.

Correlation of Impedance Threshold Device use during cardiopulmonary resuscitation with post-cardiac arrest Acute Kidney Injury

PURPOSE

To assess whether use of Impedance Threshold Device (ITD) during cardiopulmonary resuscitation (CPR) reduces the degree of post-cardiac arrest Acute Kidney Injury (AKI), as a result of improved hemodynamics, in a porcine model of ventricular fibrillation (VF) cardiac arrest.

METHODS

After 8 min of untreated cardiac arrest, the animals were resuscitated either with active compression-decompression (ACD) CPR plus a sham ITD (control group, n=8) or with ACD-CPR plus an active ITD (ITD group, n=8). Adrenaline was administered every 4 min and electrical defibrillation was attempted every 2 min until return of spontaneous circulation (ROSC) or asystole. After ROSC the animals were monitored for 6 h under general anesthesia and then returned to their cages for a 48 h observation, before euthanasia. Two novel biomarkers, Neutrophil Gelatinase-Associated Lipocalin (NGAL) in plasma and Interleukin-18 (IL-18) in urine, were measured at 2 h, 4 h, 6 h, 24 h and 48 h post-ROSC, in order to assess the degree of AKI.

RESULTS

ROSC was observed in 7 (87.5%) animals treated with the sham valve and 8 (100%) animals treated with the active valve (P=NS). However, more than twice as many animals survived at 48 h in the ITD group (n=8, 100%) compared to the control group (n=3, 37.5%). Urine IL-18 and plasma NGAL levels were augmented post-ROSC in both groups, but they were significantly higher in the control group compared with the ITD group, at all measured time points.

CONCLUSION

Use of ITD during ACD-CPR improved hemodynamic parameters, increased 48 h survival and decreased the degree of post-cardiac arrest AKI in the resuscitated animals.

Renal Doppler and Novel Biomarkers to Assess Acute Kidney Injury in a Swine Model of Ventricular Fibrillation Cardiac Arrest

Background:

Majority of the research on cardiac arrest (CA) have focused on post-CA brain injury and myocardial dysfunction, the renal dysfunction and acute kidney injury (AKI) in other critical illnesses after CA have not been well described. This study was designed to assess AKI with renal Doppler and novel AKI biomarkers in a swine model of ventricular fibrillation cardiac arrest (VFCA).

Methods:

Thirty healthy piglets were divided into VFCA group (n = 22) and Sham group (n = 8) in a blinded manner. Mean arterial pressure, heart rate, and cardiac output were recorded continuously. Cardiac arrest (CA) was induced by programmed electric stimulation in the VFCA group, and then cardiopulmonary resuscitation was performed. Twenty piglets returned of spontaneous circulation (ROSC) and received intensive care. Blood and urine samples were collected for AKI biomarkers testing, and Color Doppler flow imaging was performed at baseline, 6 h, 12 h, and 24 h, respectively after ROSC. At ROSC 24 h, the animals were sacrificed and a semi-quantitative evaluation of pathologic kidney injury was performed.

Results:

In the VFCA group, corrected resistive index (cRI) increased from 0.47 ± 0.03 to 0.64 ± 0.06, and pulsatility index (PI) decreased from 0.82 ± 0.03 to 0.68 ± 0.04 after ROSC. Cystatin C (CysC) in both serum and urine samples increased at ROSC 6 h, but neutrophil gelatinase-associated lipocalin (NGAL) in serum increased to 5.34 ± 1.68 ng/ml at ROSC 6 h, and then decreased to 3.16 ± 0.69 ng/ml at ROSC 24 h while CysC increasing constantly. According to the renal histopathology, 18 of 20 animals suffered from kidney injury. The grade of renal injury was highly correlated with RI, cRI, NGAL, and CysC. Linear regression equation was established: Grade of renal injury = 0.002 × serum CysC + 6.489 × PI + 4.544 × cRI – 8.358 (r² = 0.698, F = 18.506, P < 0.001).

Conclusions:

AKI is common in post-CA syndrome. Renal Doppler and novel AKI biomarkers in serum and urine are of significant importance as early predictors of post-CA AKI.

Inflammatory mechanisms involved in brain injury following cardiac arrest and cardiopulmonary resuscitation

Cardiac arrest (CA) is a leading cause of fatality and long-term disability worldwide. Recent advances in cardiopulmonary resuscitation (CPR) have improved survival rates; however, the survivors are prone to severe neurological injury subsequent to successful CPR following CA. Effective therapeutic options to protect the brain from CA remain limited, due to the complexities of the injury cascades caused by global cerebral ischemia/reperfusion (I/R). Although the precise mechanisms of neurological impairment following CA-initiated I/R injury require further clarification, evidence supports that one of the key cellular pathways of cerebral injury is inflammation. The inflammatory response is orchestrated by activated glial cells in response to I/R injury. Increased release of danger-associated molecular pattern molecules and cellular dysfunction in activated microglia and astrocytes contribute to ischemia-induced cytotoxic and pro-inflammatory cytokines generation, and ultimately to delayed death of neurons. Furthermore, cytokines and adhesion molecules generated within activated microglia, as well as astrocytes, are involved in the innate immune response; modulate influx of peripheral immune and inflammatory cells into the brain, resulting in neurological injury. The present review discusses the molecular aspects of immune and inflammatory mechanisms in global cerebral I/R injury following CA and CPR, and the potential therapeutic strategies that target neuroinflammation and the innate immune system.

Cardiopulmonary resuscitation using electrically driven devices: a review

In the treatment of sudden cardiac arrest (SCA) immediate resuscitation with chest compressions and ventilation is crucial for survival. As manual resuscitation is associated with several drawbacks, mechanical resuscitation devices have been developed to support resuscitation teams. These devices are able to achieve better perfusion of heart and brain in laboratory settings, but real world experience showed no significant improved survival in comparison to manual resuscitation. This review will focus on two mechanical resuscitation devices, the Lund University Cardiac Assist System (LUCAS) and AutoPulse devices and the actual literature available. In conclusion, the general use of mechanical resuscitation devices cannot be recommended at the moment.

Home Care Providers to the Rescue: A Novel First-Responder Programme

AIM

To describe the implementation of a novel first-responder programme in which home care providers equipped with automated external defibrillators (AEDs) were dispatched in parallel with existing emergency medical services in the event of a suspected out-of-hospital cardiac arrest (OHCA).

METHODS

We evaluated a one-year prospective study that trained home care providers in performing cardiopulmonary resuscitation (CPR) and using an AED in cases of suspected OHCA. Data were collected from cardiac arrest case files, case files from each provider dispatch and a survey among dispatched providers. The study was conducted in a rural district in Denmark.

RESULTS

Home care providers were dispatched to 28 of the 60 OHCAs that occurred in the study period. In ten cases the providers arrived before the ambulance service and subsequently performed CPR. AED analysis was executed in three cases and shock was delivered in one case. For 26 of the 28 cases, the cardiac arrest occurred in a private home. Ninety-five per cent of the providers who had been dispatched to a cardiac arrest reported feeling prepared for managing the initial resuscitation, including use of AED.

CONCLUSION

Home care providers are suited to act as first-responders in predominantly rural and residential districts. Future follow-up will allow further evaluation of home care provider arrivals and patient survival.

Providers with Limited Experience Perform Better in Advanced Life Support with Assistance Using an Interactive Device with an Automated External Defibrillator Linked to a Ventilator

BACKGROUND

Medical teams with limited experience in performing advanced life support (ALS) or with a low frequency of cardiopulmonary resuscitation (CPR) while on duty, often have difficulty complying with CPR guidelines.

OBJECTIVE

This study evaluated whether the quality of CPR of trained medical students, who served as an example of teams with limited experience in ALS, could be improved with device assistance. The primary outcome was the hands-off time (i.e., the percentage of the entire CPR time without chest compressions). The secondary outcome was seven time intervals, which should be as short as possible, and the quality of ventilations and chest compressions on the mannequin.

METHODS

We compared standard CPR equipment to an interactive device with visual and acoustic instructions for ALS workflow measures to guide briefly trained medical students through the ALS algorithm in a full-scale mannequin simulation study with a randomized crossover study design. The study equipment consisted of an automatic external defibrillator and ventilator that were electronically linked and communicating as a single system. Included were regular medical students in the third to sixth years of medical school of one class who provided written informed consent for voluntary participation and for the analysis of their CPR performance data. No exclusion criteria were applied. For statistical measures of evaluation we used an analysis of variance for crossover trials accounting for treatment effect, sequence effect, and carry-over effect, with adjustment for prior practical experience of the participants.

RESULTS

Forty-two medical students participated in 21 CPR sessions, each using the standard and study equipment. Regarding the primary end point, the study equipment reduced the hands-off time from 40.1% (95% confidence interval [CI] 36.9-43.4%) to 35.6% (95% CI 32.4-38.9%, p = 0.031) compared with the standard equipment. Within the prespecified secondary end points, study equipment reduced the time interval until the first rescuer changeover from 273 s (95% CI 244-302 s) to 223 s (95% CI 194-253 s, p = 0.001) and increased the percentage of ventilations with a correct tidal volume of 400-600 mL from 34.3% (95% CI 19.0-49.6%) to 60.9% (95% CI 45.6-76.2%, p = 0.018).

CONCLUSIONS

The assist device increased the rescuers' CPR quality. CPR providers with limited experience or a limited frequency of CPR performance (i.e., rural Emergency Medical Services crew) may potentially benefit from this assist device.

Risk factor analyses for the return of spontaneous circulation in the asphyxiation cardiac arrest porcine model

Background:

Animal models of asphyxiation cardiac arrest (ACA) are frequently used in basic research to mirror the clinical course of cardiac arrest (CA). The rates of the return of spontaneous circulation (ROSC) in ACA animal models are lower than those from studies that have utilized ventricular fibrillation (VF) animal models. The purpose of this study was to characterize the factors associated with the ROSC in the ACA porcine model.

Methods:

Forty-eight healthy miniature pigs underwent endotracheal tube clamping to induce CA. Once induced, CA was maintained untreated for a period of 8 min. Two minutes following the initiation of cardiopulmonary resuscitation (CPR), defibrillation was attempted until ROSC was achieved or the animal died. To assess the factors associated with ROSC in this CA model, logistic regression analyses were performed to analyze gender, the time of preparation, the amplitude spectrum area (AMSA) from the beginning of CPR and the pH at the beginning of CPR. A receiver-operating characteristic (ROC) curve was used to evaluate the predictive value of AMSA for ROSC.

Results:

ROSC was only 52.1% successful in this ACA porcine model. The multivariate logistic regression analyses revealed that ROSC significantly depended on the time of preparation, AMSA at the beginning of CPR and pH at the beginning of CPR. The area under the ROC curve in for AMSA at the beginning of CPR was 0.878 successful in predicting ROSC (95% confidence intervals: 0.773∼0.983), and the optimum cut-off value was 15.62 (specificity 95.7% and sensitivity 80.0%).

Conclusions:

The time of preparation, AMSA and the pH at the beginning of CPR were associated with ROSC in this ACA porcine model. AMSA also predicted the likelihood of ROSC in this ACA animal model.

The survival benefit of dual dispatch of EMS and fire-fighters in out-of-hospital cardiac arrest may differ depending on population density--a prospective cohort study

BACKGROUND

Outcome after out-of-hospital cardiac arrest (OHCA) varies between contexts. Dual dispatching of fire-fighters or police in addition to emergency medical services (EMS) has the potential to increase survival, but the effect in urban vs. rural areas is unknown. The aim of this study was to determine the effects of dual dispatching on response times and outcome in regions with different population density.

METHODS AND RESULTS

The study design was a prospective cohort study of EMS-treated OHCAs from 2004 (historical controls, only EMS dispatch) and 2006-2009 (intervention, dual dispatch of EMS and fire-fighters), with data on exact geographical coordinates. Patients were divided into four subgroups depending on population density: rural (<250 persons/km2), suburban (250-2999/km2), urban (3000-5999/km2) and downtown (≥6000/km2). Totally, 2513 OHCAs were included (historical controls, n=571 and intervention, n=1942). Median time to arrival of first unit shortened significantly in all subgroups, ranging from 0.8 to 3.2 min, with the main time gain in the rural area. There were significant differences in 30-day survival between the historical controls vs. the intervention group in the suburban population (3.1% vs. 7.0%, p=0.02) and in downtown (4.1 vs. 14.6, p=0.04). In the urban population the difference was 2.7 vs. 6.9% (p=0.06) and in the rural population (4.7 vs. 5.3, p=0.82).

CONCLUSIONS

Dual dispatch of fire-fighters and EMS in OHCA significantly reduced response times in all studied regions. The 30-day survival increased significantly in the downtown and suburban populations, while a limited impact was seen in the rural areas.

Quality of continuous chest compressions performed for one or two minutes

OBJECTIVES

This study was designed to assess cardiopulmonary resuscitation quality and rescuer fatigue when rescuers perform one or two minutes of continuous chest compressions.

METHODS

This prospective crossover study included 148 lay rescuers who were continuously trained in a cardiopulmonary resuscitation course. The subjects underwent a 120-min training program comprising continuous chest compressions. After the course, half of the volunteers performed one minute of continuous chest compressions, and the others performed two minutes, both on a manikin model. After 30 minutes, the volunteers who had previously performed one minute now performed two minutes on the same manikin and vice versa.

RESULTS

A comparison of continuous chest compressions performed for one and two minutes, respectively, showed that there were significant differences in the average rate of compressions per minute (121 vs. 124), the percentage of compressions of appropriate depth (76% vs. 54%), the average depth (53 vs. 47 mm), and the number of compressions with no errors (62 vs. 47%). No parameters were significantly different when comparing participants who performed regular physical activity with those who did not and participants who had a normal body mass index with overweight/obese participants.

CONCLUSION

The quality of continuous chest compressions by lay rescuers is superior when it is performed for one minute rather than for two minutes, independent of the body mass index or regular physical activity, even if they are continuously trained in cardiopulmonary resuscitation. It is beneficial to rotate rescuers every minute when performing continuous chest compressions to provide higher quality and to achieve greater success in assisting a victim of cardiac arrest.

[Saving lives with dispatcher-assisted resuscitation: importance of effective telephone instruction]

BACKGROUND

Survival rates after sudden cardiac arrest could be increased if bystanders could be encouraged to perform CPR until emergency services arrive. This should be initiated by the dispatcher at the emergency control facility who receives the call. For the first time the ERC guidelines of 2010 included instructions to be given to untrained rescuers by the dispatcher. Rapid recognition of cardiac arrest and initiation of emergency measures is assured by means of specific training for the dispatchers.

AIM

The aim of this investigation was to determine whether the time between an emergency call and beginning of cardiopulmonary resuscitation (CPR) could be shortened using a simple protocol and whether a relationship exists between the intensity of phone contact between dispatcher and caller and if this improves the results.

MATERIALS AND METHODS

In known cases of unconsciousness, group 1 (45 persons) received short CPR instructions via the phone, where the dispatcher was on the phone for continuous advice until emergency services arrived. Group 2 (45 persons) received identical phone instructions like group 1, but the phone call was terminated by the dispatcher after the information was provided. Group 3 (29 persons) only received instructions to start CPR.

RESULTS

On average, all test persons in group 1 started reanimation after 68.0 ± 33.5 s, in group 2 after 68.3 ± 25.2 s, and in group 3 after 64.9 ± 34.4 s. The compression frequency on average was 98.3/min in group 1, 84.8/min in group 2, and 85.2/min in group 3; therefore, all groups reached an average frequency of > 80/min. The correct compression depth was achieved by 47.8 % of test persons in group 1, by 44.2 % in group 2, and by 30.2 % in group 3. All volunteers felt well supported. Of the 90 people, 70 did not feel that they were missing instructions.

DISCUSSION

There were no significant differences between the groups regarding the target variables. The results show that already extremely short instructions or advice by the dispatcher to start CPR is sufficient to encourage bystanders to give assistance in an emergency. Continuous support over the phone does not appear to be necessary.