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.

Pre-hospital antibiotic therapy preceded by blood cultures in a physician-manned mobile emergency care unit.

BACKGROUND: Rapid recognition and antibiotic treatment, preferably preceded by blood cultures (BCs), is a mainstay in sepsis therapy. The objective of this investigation was to determine if pre-hospital BCs were feasible and drawn with an acceptably low level of contamination and to investigate whether pre-hospital antibiotics were administered on correct indications. METHODS: We performed a register-based study in a pre-hospital physician-manned mobile emergency care unit (MECU) operating in a mixed urban/rural area in Denmark. All patients who received pre-hospital antibiotics by the MECU from November 2013 to October 2018 were reviewed. Outcome measures were characterisation of microbial findings and subsequent in-hospital confirmation of the pre-hospital indication for antibiotics. RESULTS: One-hundred-and-nineteen patients received antibiotics pre-hospitally. Six were excluded. One-hundred-and-thirteen patients were included in the study. BCs were drawn in 107 of the 113 patients (94.7% [88.8%-98.0%]). We found a true pathogen of sepsis in 29 (27.1% [19.0%-36.6%]) of these 107 patients. Nine (8.4% [3.9%-15.4%]) patients had contaminated pre-hospital BCs. Forty-nine of all patients (36.3% [27.4%-45.9%]) had causative pathogens in either their BCs or other samples confirming the pre-hospital tentative diagnosis. Eighty-two (72.6% [63.4%-80.5%]) patients received antibiotic therapy in-hospitally, while 27 (23.9% [16.4%-32.8%]) were assigned an in-hospital diagnosis not associated with infection. Four (3.5% [1.0%-8.8%]) patients died in hospital before a diagnosis was established. CONCLUSIONS: Pre-hospital administration of antibiotics preceded by BCs is feasible, although with somewhat high blood culture contamination rates. Antibiotics are administered on reasonable indications.

Ketamine as an Anesthetic for Patients with Acute Brain Injury: A Systematic Review.

For years, the use of ketamine as an anesthetic to patients suffering from acute brain injury has been debated because of its possible deleterious effects on the cerebral circulation and thus on the cerebral perfusion. Early studies suggested that ketamine could increase the intracranial pressure thus lowering the cerebral perfusion and hence reduce the oxygen supply to the injured brain. However, more recent studies are less conclusive and might even indicate that patients with acute brain injury could benefit from ketamine sedation. This systematic review summarizes the evidence regarding the use of ketamine in patients suffering from traumatic brain injury. Databases were searched for studies using ketamine in acute brain injury. Outcomes of interest were mortality, intracranial pressure, cerebral perfusion pressure, blood pressure, heart rate, spreading depolarizations, and neurological function. In total 11 studies were included. The overall level of evidence concerning the use of ketamine in brain injury is low. Only two studies found a small increase in intracranial pressure, while two small studies found decreased levels of intracranial pressure following ketamine administration. We found no evidence of harm during ketamine use in patients suffering from acute brain injury.

Association of Real-Time Feedback and Cardiopulmonary-Resuscitation Quality Delivered by Ambulance Personnel for Out-of-Hospital Cardiac Arrest.

Background High-quality cardiopulmonary resuscitation (CPR) is associated with improved survival from out-of-hospital cardiac arrest and includes chest compression depth, chest compression rate, and chest compression fraction within international guideline recommendations. Previous studies have demonstrated divergent results of real-time feedback on CPR performance and patient outcomes. This study investigated the association between emergency medical service CPR quality and real-time CPR feedback for out-of-hospital cardiac arrest. Methods and Results This study collected out-of-hospital cardiac arrest data within the Capital Region of Denmark and compared CPR quality delivered by ambulance personnel. Data were collected in 2 consecutive phases from October 2018 to February 2020. Median chest compression depth was 6.0 cm (no feedback) and 5.9 cm (real-time feedback) (P=0.852). Corresponding proportion of guideline-compliant chest compressions for depth was 16.6% and 28.7%, respectively (P<0.001). Median chest compression rate per minute was 111 and 109 (P<0.001), respectively. Corresponding guideline adherence proportion for compression rate was 65.4% compared with 80.4% (P<0.001), respectively. Chest compression fraction was 78.9% compared with 81.9% (P<0.001), respectively. The combination of guideline-compliant chest compression depth and chest compression rate simultaneously was 8.5% (no feedback) versus 18.8% (feedback) (P<0.001). Improvements were not significant for return of spontaneous circulation (odds ratio [OR], 1.08 [95% CI, 0.84-1.39]), sustained return of spontaneous circulation (OR, 1.00 [95% CI, 0.77-1.31]), or survival to hospital discharge (OR, 0.91 [95% CI, 0.64-1.30]). Conclusions Real-time feedback was associated with improved guideline compliance for chest compression depth, rate, and fraction but not return of spontaneous circulation, sustained return of spontaneous circulation, or survival to hospital discharge. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04152252.

Association Between Number of Volunteer Responders and Interventions Before Ambulance Arrival for Cardiac Arrest.

BACKGROUND: Volunteer responder (VR) programs for activation of laypersons in out-of-hospital cardiac arrest (OHCA) have been deployed worldwide, but the optimal number of VRs to dispatch is unknown. OBJECTIVES: The purpose of this study was to investigate the association between the number of VRs arriving before Emergency Medical Services (EMS) and the proportion of bystander cardiopulmonary resuscitation (CPR) and defibrillation. METHODS: We included OHCAs not witnessed by EMS with VR activation from the Capital Region (September 2, 2017, to May 14, 2019) and the Central Region of Denmark (November 5, 2018, to December 31, 2019). We created 4 groups according to the number of VRs arriving before EMS: 0, 1, 2, and 3 or more. Using a logistic regression model adjusted for EMS response time, we examined associations between the number of VRs arriving before EMS and bystander CPR and defibrillation. RESULTS: We included 906 OHCAs. The adjusted ORs for bystander CPR were 2.40 (95% CI: 1.42-4.05), 3.18 (95% CI: 1.39-7.26), and 2.70 (95% CI: 1.32-5.52) when 1, 2, or 3 or more VRs arrived before EMS (reference), respectively. The adjusted OR for bystander defibrillation increased when 1 (1.97 [95% CI: 1.12-3.52]), 2 (2.88 [95% CI: 1.48-5.58]), or 3 or more (3.85 [95% CI: 2.11-7.01]) VRs arrived before EMS (reference). The adjusted OR of bystander defibrillation increased to 1.95 (95% CI: 1.18-3.22) when ≥3 VRs arrived first compared with 1 VR arriving first (reference). CONCLUSIONS: We found an association of increased bystander CPR and defibrillation when 1 or more VRs arrived before the EMS with a trend toward increased bystander defibrillation with increasing number of VRs arriving first.

Volunteer responder provision of support to relatives of out-of-hospital cardiac arrest patients: a qualitative study.

OBJECTIVES: Smartphone dispatch of volunteer responders for out-of-hospital cardiac arrest (OHCA) is implemented worldwide. While basic life support courses prepare participants to provide CPR, the courses rarely address the possibility of meeting a family member or relative in crisis. This study aimed to examine volunteer responders' provision of support to relatives of cardiac arrest patients and how relatives experienced the interaction with volunteer responders. DESIGN: In this qualitative study, we conducted 16 semistructured interviews with volunteer responders and relatives of cardiac arrest patients. SETTING: Interviews were conducted face to face and by video and recorded and transcribed verbatim. PARTICIPANTS: Volunteer responders dispatched to cardiac arrests and relatives of cardiac arrest patients were included in the study. Participants were included from all five regions of Denmark. RESULTS: A thematic analysis was performed with inspiration from Braun and Clarke. We identified three themes: (1) relatives' experiences of immediate relief at arrival of assistance, (2) volunteer responders' assessment of relatives' needs and (3) the advantage of being healthcare educated. CONCLUSIONS: Relatives to out-of-hospital cardiac arrest patients benefited from volunteer responders' presence and support and experienced the mere presence of volunteer responders as supportive. Healthcare-educated volunteer responders felt confident and skilled to provide care for relatives, while some non-healthcare-educated volunteer responders felt they lacked the proper training and knowledge to provide emotional support for relatives. Future basic life support courses should include a lesson on how to provide emotional support to relatives of cardiac arrest patients.

Association of Degree of Urbanization and Survival in Out-of-Hospital Cardiac Arrest.

Background Survival from out-of-hospital cardiac arrest (OHCA) varies across regions. The aim of this study was to evaluate the association between urbanization (rural, suburban, and urban areas), bystander interventions (cardiopulmonary resuscitation and defibrillation), and 30-day survival from OHCAs in Denmark. Methods and Results We included OHCAs not witnessed by ambulance staff in Denmark from January 1, 2016, to December 31, 2020. Patients were divided according to the Eurostat Degree of Urbanization Tool in rural, suburban, and urban areas based on the 98 Danish municipalities. Poisson regression was used to estimate incidence rate ratios. Logistic regression (adjusted for ambulance response time) tested differences between the groups with respect to bystander interventions and survival, according to degree of urbanization. A total of 21 385 OHCAs were included, of which 8496 (40%) occurred in rural areas, 7025 (33%) occurred in suburban areas, and 5864 (27%) occurred in urban areas. Baseline characteristics, as age, sex, location of OHCA, and comorbidities, were comparable between groups. The annual incidence rate ratio of OHCA was higher in rural areas (1.54 [95% CI, 1.48-1.58]) compared with urban areas. Odds for bystander cardiopulmonary resuscitation were lower in suburban (0.86 [95% CI, 0.82-0.96]) and urban areas (0.87 [95% CI, 0.80-0.95]) compared with rural areas, whereas bystander defibrillation was higher in urban areas compared with rural areas (1.15 [95% CI, 1.01-1.31]). Finally, 30-day survival was higher in suburban (1.13 [95% CI, 1.02-1.25]) and urban areas (1.17 [95% CI, 1.05-1.30]) compared with rural areas. Conclusions Degree of urbanization was associated with lower rates of bystander defibrillation and 30-day survival in rural areas compared with urban areas.

Functionality of registered automated external defibrillators.

AIMS: Little is known about automated external defibrillator (AED) functionality in real-life settings. We aimed to assess the functionality of all registered AEDs in a geographically selected area and calculate the proportion of historical out-of-hospital cardiac arrests (OHCAs) covered by non-functioning AEDs. METHODS: In this cross-sectional study we inspected all registered and available AEDs on the island of Bornholm in Denmark. We collected information on battery status (determined by AED self-test) and electrode status, as well as AED availability. We identified all historical OHCAs registered with the Danish Cardiac Arrest Registry on Bornholm during 2016-2019 and calculated the proportion of OHCAs covered by an AED (regardless of functionality status) within ≤100, ≤750, and ≤1800 meters and the proportion of OHCAs covered by non-functioning AEDs. RESULTS: Of 211 registered AEDs, 181 (81.9%) were publicly accessible and functional. The remaining 40 (18.1%) were not functional, primarily due to expired electrodes (42.5%, n = 17), obstacles to AED retrieval (20.0%, n = 8) or failed self-tests (17.5%, n = 7). Of 197 historical OHCAs, non-functional AEDs resulted in an OHCA coverage loss of 5.6%, 4.1% and 1.0 % for ≤100 m, ≤750 m and ≤1800 m, respectively. CONCLUSION: Almost one-fifth of all registered and publicly available AEDs were not functional, primarily due to expired electrodes, failed self-tests or obstacles to retrieving AEDs. One in twenty historical OHCA was covered by a non-functional AED. Although general AED functionality was high, this finding underlines the importance of regular AED maintenance.

Activation of Citizen Responders to Out-of-Hospital Cardiac Arrest During the COVID-19 Outbreak in Denmark 2020.

Background Little is known about how COVID-19 influenced engagement of citizen responders dispatched to out-of-hospital cardiac arrest (OHCA) by a smartphone application. The objective was to describe and analyze the Danish Citizen Responder Program and bystander interventions (both citizen responders and nondispatched bystanders) during the first COVID-19 lockdown in 2020. Methods and Results All OHCAs from January 1, 2020, to June 30, 2020, with citizen responder activation in 2 regions of Denmark were included. We compared citizen responder engagement for OHCA in the nonlockdown period (January 1, 2020, to March 10, 2020, and April 21, 2020, to June 30, 2020) with the lockdown period (March 11, 2020, to April 20, 2020). Data are displayed in the order lockdown versus nonlockdown period. Bystander cardiopulmonary resuscitation rates did not differ in the 2 periods (99% versus 92%; P=0.07). Bystander defibrillation (9% versus 14%; P=0.4) or return-of-spontaneous circulation (23% versus 23%; P=1.0) also did not differ. A similar amount of citizen responders accepted alarms during the lockdown (6 per alarm; interquartile range, 6) compared with the nonlockdown period (5 per alarm; interquartile range, 5) (P=0.05). More citizen responders reported performing chest-compression-only cardiopulmonary resuscitation during lockdown compared with nonlockdown (79% versus 59%; P=0.0029), whereas fewer performed standardized cardiopulmonary resuscitation, including ventilations (19% versus 38%; P=0.0061). Finally, during lockdown, more citizen responders reported being not psychologically affected by attending an OHCA compared with nonlockdown period (68% versus 56%; P<0.0001). Likewise, fewer reported being mildly affected during lockdown (26%) compared with nonlockdown (35%) (P=0.003). Conclusions The COVID-19 lockdown in Denmark was not associated with decreased bystander-initiated resuscitation in OHCAs attended by citizen responders.

Improving survival after out-of-hospital cardiac arrest.

During the past 20 years the survival after out-of-hospital cardiac arrest (OHCA) has almost quadrupled from 4% in 2001 to 14% in 2020. There has been a huge focus on layman education in cardiopulmonary resuscitation and use of automated external defibrillators (AED), implementation of healthcare staff at 1-1-2 dispatch centers, early recognition of OHCA, establishment of a national AED register with publicly available AEDs, and dispatch of volunteer responders in case of nearby OHCA. This review describes implemented initiatives with the purpose of improving survival from OHCA in Denmark.

Increased bystander intervention when volunteer responders attend out-of-hospital cardiac arrest.

Aim: The primary aim was to investigate the association between alarm acceptance compared to no-acceptance by volunteer responders, bystander intervention, and survival in out-of-hospital cardiac arrest. Materials and methods: This retrospective observational study included all suspected out-of-hospital cardiac arrests (OHCAs) with activation of volunteer responders in the Capital Region of Denmark (1 November 2018 to 14 May 2019), the Central Denmark Region (1 November 2018 to 31 December 2020), and the Northern Denmark Region (14 February 2020 to 31 December 2020). All OHCAs unwitnessed by Emergency Medical Services (EMS) were analyzed on the basis on alarm acceptance and arrival before EMS. The primary outcomes were bystander cardio-pulmonary resuscitation (CPR), bystander defibrillation and secondary outcome was 30-day survival. A questionnaire sent to all volunteer responders was used with respect to their arrival status. Results: We identified 1,877 OHCAs with volunteer responder activation eligible for inclusion and 1,725 (91.9%) of these had at least one volunteer responder accepting the alarm (accepted). Of these, 1,355 (79%) reported arrival status whereof 883 (65%) arrived before EMS. When volunteer responders accepted the alarm and arrived before EMS, we found increased proportions and adjusted odds ratio for bystander CPR {94 vs. 83%, 4.31 [95% CI (2.43-7.67)] and bystander defibrillation [13 vs. 9%, 3.16 (1.60-6.25)]} compared to cases where no volunteer responders accepted the alarm. Conclusion: We observed a fourfold increased odds ratio for bystander CPR and a threefold increased odds ratio for bystander defibrillation when volunteer responders accepted the alarm and arrived before EMS.

Impact of dispatcher-assisted cardiopulmonary resuscitation on neurologically intact survival in out-of-hospital cardiac arrest: a systematic review.

BACKGROUND: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) increases neurologically intact survival in out-of-hospital cardiac arrest (OHCA) according to several studies. This systematic review summarizes neurologically intact survival outcomes of DA-CPR in comparison with bystander-initiated CPR and no bystander CPR in OHCA. METHODS: The systematic review was conducted according to the PRISMA guidelines. All studies including adult and/or pediatric OHCAs that compared DA-CPR with bystander-initiated CPR or no bystander CPR were included. Primary outcome was neurologically intact survival at discharge, one-month or longer. Studies were searched for in PubMed (MEDLINE), EMBASE, and the Cochrane Library databases. The risk of bias was evaluated using the Newcastle-Ottawa Scale. RESULTS: The search string generated 4742 citations of which 33 studies were eligible for inclusion. Due to overlapping study populations, the review included 14 studies. All studies were observational. The study populations were heterogeneous and included adult, pediatric and mixed populations. Some studies reported only witnessed cardiac arrests, arrests of cardiac ethiology, and/or shockable rhythm. The individual studies scored between six and nine on the Newcastle-Ottawa Scale of risk of bias. The median neurologically intact survival at hospital discharge with DA-CPR was 7.0% (interquartile range (IQR): 5.1-10.8%), with bystander-initiated CPR 7.5% (IQR: 6.6-10.2%), and with no bystander CPR 4.4% (IQR: 2.0-9.0%) (four studies). At one-month neurologically intact survival with DA-CPR was 3.1% (IQR: 1.6-3.4%), with bystander-initiated CPR 5.7% (IQR: 5.0-6.0%), and with no bystander CPR 2.5% (IQR: 2.1-2.6%) (three studies). CONCLUSION: Both DA-CPR and bystander-initiated CPR increase neurologically intact survival compared with no bystander CPR. However, DA-CPR demonstrates inferior outcomes compared with bystander-initiated CPR. Early CPR is crucial, thus in cases where bystanders have not initiated CPR, DA-CPR provides an opportunity to improve neurologically intact survival following OHCA. Variability in OHCA outcomes across studies and multiple confounding factors were identified.

[Christmas article: Consumption of chocolate vs candy in a Danish emergency department].

INTRODUCTION: The main objective of this single-centre, prospective, observational study was to compare the survival rate of chocolate with that of candy among healthcare professionals working in an emergency department. Secondary objectives included comparisons of cumulative weight, calorie count, and cost of consumed chocolate vs candy. METHODS: On five separate occasions, an observer with recurring duty in the emergency department placed 56 pieces of milk chocolate (30% cocoa) and 56 pieces of candy (wine gum and liquorice) next to each other in standard, disposable bowls, in one of two prespecified locations. These bowls were continuously monitored for two hours. The primary outcome, i.e., the survival of chocolate vs candy, was evaluated using Kaplan-Meier analysis with the log-rank test and Cox proportional hazards regression. Secondary outcomes were compared using unpaired t-test. RESULTS: Of the 560 pieces of sweets distributed 257 were consumed, 108 pieces of chocolate and 149 pieces of candy. The survival of chocolate was significantly longer than that of candy, hazard ratio for chocolate vs candy was 0.66 (95% confidence interval: 0.52-0.85), p = 0.001. Chocolate was responsible for significantly more weight eaten (771 g vs 497 g), calories consumed (4,243 kcal vs 1,723 kcal), and cost (81 SEK vs 38 SEK), p < 0.001 for all. CONCLUSION: Pieces of chocolate survived significantly longer than pieces of candy. FUNDING: none. TRIAL REGISTRATION: not relevant.