Cardiac arrest in public locations--an independent predictor for better outcome?

Pre-Arrival Care of the Out-of-Hospital Cardiac Arrest Victim

Lay rescuers play a pivotal role in the recognition and initial management of out-of-hospital cardiac arrest. The provision of timely pre-arrival care by lay responders, including cardiopulmonary resuscitation and the use of automated external defibrillator before emergency medical service arrival, is important link in the chain of survival and has been shown to improve outcomes from cardiac arrest. Although physicians are not directly involved in bystander response to cardiac arrest, they play a key role in emphasizing the importance of bystander interventions.

Prognostic predictors in patients with cardiopulmonary arrest: A novel equation for evaluating the 30-day mortality

BACKGROUND

Early prediction of outcomes after cardiopulmonary arrest (CPA) is important for considering the best support. Our purpose was to evaluate predictors of the 30-day mortality in patients with CPA after return of spontaneous circulation (ROSC) and to assess an equation for calculating the 30-day mortality using clinical parameters.

METHODS

We retrospectively analyzed the data of 194 consecutive patients with CPA and ROSC in a derivation study (2015-2022). We compared clinical parameters between the survived (n = 78) and dead (n = 116) patients. We derived an equation for estimated probability of death based on clinical parameters, using multivariate logistic regression analysis. The reliability of the equation was validated in 80 additional patients with CPA.

RESULTS

The 30-day mortality was associated with sex, witnessed cardiac arrest, bystander cardiopulmonary resuscitation (CPR), CPA due to acute myocardial infarction, pupil diameter, Glasgow Coma Scale score (GCS), presence of light reflex, arterial or venous pH, lactate levels, initial ventricular fibrillation (VF), CPA time, and age. The derived logistic regression equation was as follows: Estimated probability of death = 1 / (1 + e-x), x = (0.25 × bystander CPR) + (0.44 × pupil diameter) - (0.14 × GCS) + (0.09 × lactate) - (1.87 × initial VF) + (0.07 × CPA time) + (0.05 × age) - 7.03. The cut-off value for estimated probability of death calculated by this equation was 54.5 %, yielding a sensitivity, specificity, and accuracy of 86.2 %, 80.8 %, and 84.5 %, respectively. In the validation model, these values were 81.8 %, 85.7 %, and 82.5 %, respectively.

CONCLUSIONS

The 30-day mortality may be calculated after ROSC in patients with CPA using simple clinical parameters. This equation may facilitate further best support for patients with CPA.

The association of the post-resuscitation on-scene interval and patient outcomes after out-of-hospital cardiac arrest

BACKGROUND

After resuscitation from out-of-hospital cardiac arrest (OHCA) by Emergency Medical Services (EMS), the amount of time that should be dedicated to pre-transport stabilization is unclear. We examined whether the time spent on-scene after return of spontaneous circulation (ROSC) was associated with patient outcomes.

METHODS

We examined consecutive adult EMS-treated OHCAs from the British Columbia Cardiac Arrest registry (January 1/2019-June 1/2021) that had on-scene ROSC (sustained to scene departure). The primary outcome was favourable neurological outcome (Cerebral Performance Category ≤ 2) at hospital discharge; secondary outcomes were re-arrest during transport and hospital-discharge survival. Using adjusted logistic regression models, we estimated the association between the post-resuscitation on-scene interval (divided into quartiles) and outcomes.

RESULTS

Of 1653 cases, 611 (37%) survived to hospital discharge, and 523 (32%) had favourable neurological outcomes. The median post-resuscitation on-scene interval was 18.8 minutes (IQR:13.0-25.5). Compared to the first post-resuscitation on-scene interval quartile, neither the second (adjusted odds ratio [AOR] 1.19; 95% CI 0.72-1.98), third (AOR 1.10; 95% CI 0.67-1.81), nor fourth (AOR 1.54; 95% CI 0.93-2.56) quartiles were associated with favourable neurological outcomes; however, the fourth quartile was associated with a greater odds of hospital-discharge survival (AOR 1.73; 95% CI 1.05-2.85), and both the third (AOR 0.40; 95% CI 0.22-0.72) and fourth (AOR 0.44;95% CI 0.24-0.81) quartiles were associated with a lower odds of intra-transport re-arrest.

CONCLUSION

Among resuscitated OHCAs, increased post-resuscitation on-scene time was not associated with improved neurological outcomes, but was associated with improved survival to hospital discharge and decreased intra-transport re-arrest.

Factors affecting public access defibrillator placement decisions in the United Kingdom: A survey study

Aim

This study aimed to understand current community PAD placement strategies and identify factors which influence PAD placement decision-making in the United Kingdom (UK).

Methods

Individuals, groups and organisations involved in PAD placement in the UK were invited to participate in an online survey collecting demographic information, facilitators and barriers to community PAD placement and information used to decide where a PAD is installed in their experiences. Survey responses were analysed through descriptive statistical analysis and thematic analysis.

Results

There were 106 included responses. Distance from another PAD (66%) and availability of a power source (63%) were most frequently used when respondents are deciding where best to install a PAD and historical occurrence of cardiac arrest (29%) was used the least. Three main themes were identified influencing PAD placement: (i) the relationship between the community and PADs emphasising community engagement to create buy-in; (ii) practical barriers and facilitators to PAD placement including securing consent, powering the cabinet, accessibility, security, funding, and guardianship; and (iii) 'risk assessment' methods to estimate the need for PADs including areas of high footfall, population density and type, areas experiencing health inequalities, areas with delayed ambulance response and current PAD provision.

Conclusion

Decision-makers want to install PADs in locations that maximise impact and benefit to the community, but this can be constrained by numerous social and infrastructural factors. The best location to install a PAD depends on local context; work is required to determine how to overcome barriers to optimal community PAD placement.

Microporous water with high gas solubilities

Liquids with permanent microporosity can absorb larger quantities of gas molecules than conventional solvents¹, providing new opportunities for liquid-phase gas storage, transport and reactivity. Current approaches to designing porous liquids rely on sterically bulky solvent molecules or surface ligands and, thus, are not amenable to many important solvents, including water^2-4. Here we report a generalizable thermodynamic strategy to preserve permanent microporosity and impart high gas solubilities to liquid water. Specifically, we show how the external and internal surface chemistry of microporous zeolite and metal-organic framework (MOF) nanocrystals can be tailored to promote the formation of stable dispersions in water while maintaining dry networks of micropores that are accessible to gas molecules. As a result of their permanent microporosity, these aqueous fluids can concentrate gases, including oxygen (O₂) and carbon dioxide (CO₂), to much higher densities than are found in typical aqueous environments. When these fluids are oxygenated, record-high capacities of O₂ can be delivered to hypoxic red blood cells, highlighting one potential application of this new class of microporous liquids for physiological gas transport.

Machine learning-based dispatch of drone-delivered defibrillators for out-of-hospital cardiac arrest

BACKGROUND

Drone-delivered defibrillators have the potential to significantly reduce response time for out-of-hospital cardiac arrest (OHCA). However, optimal policies for the dispatch of such drones are not yet known. We sought to develop dispatch rules for a network of defibrillator-carrying drones.

METHODS

We identified all suspected OHCAs in Peel Region, Ontario, Canada from Jan. 2015 to Dec. 2019. We developed drone dispatch rules based on the difference between a predicted ambulance response time to a calculated drone response time for each OHCA. Ambulance response times were predicted using linear regression and neural network models, while drone response times were calculated using drone specifications from recent pilot studies and the literature. We evaluated the dispatch rules based on response time performance and dispatch decisions, comparing them to two baseline policies of never dispatching and always dispatching drones.

RESULTS

A total of 3573 suspected OHCAs were included in the study with median and mean historical ambulance response times of 5.8 and 6.2 min. All machine learning-based dispatch rules significantly reduced the median response time to 3.9 min and mean response time to 4.1-4.2 min (all P < 0.001) and were non-inferior to universally dispatching drones (all P < 0.001) while reducing the number of drone flights by up to 30%. Dispatch rules with more drone flights achieved higher sensitivity but lower specificity and accuracy.

CONCLUSION

Machine learning-based dispatch rules for drone-delivered defibrillators can achieve similar response time reductions as universal drone dispatch while substantially reducing the number of trips.

Survival of patients with and without diabetes following out-of-hospital cardiac arrest: A nationwide Danish study

BACKGROUND

Research regarding out-of-hospital cardiac arrest (OHCA) survival of diabetes patients is sparse and it remains unknown whether initiatives to increase OHCA survival benefit diabetes and non-diabetes patients equally. We therefore examined overall and temporal survival in diabetes and non-diabetes patients following OHCA.

METHODS

Adult presumed cardiac-caused OHCAs were identified from the Danish Cardiac Arrest Registry (2001-2014). Associations between diabetes and return of spontaneous circulation upon hospital arrival and 30-day survival were estimated with logistic regression adjusted for patient- and OHCA-related characteristics.

RESULTS

In total, 28,955 OHCAs were included of which 4276 (14.8%) had diabetes. Compared with non-diabetes patients, diabetes patients had more comorbidities, same prevalence of bystander-witnessed arrests (51.7% vs. 52.7%) and bystander cardiopulmonary resuscitation (43.2% vs. 42.0%), more arrests in residential locations (77.3% vs. 73.0%) and were less likely to have shockable heart rhythm (23.5% vs. 27.9%). Temporal increases in return of spontaneous circulation and 30-day survival were seen for both groups (return of spontaneous circulation: 8.8% in 2001 to 22.3% in 2014 (diabetes patients) vs. 7.8% in 2001 to 25.7% in 2014 (non-diabetes patients); and 30-day survival: 2.8% in 2001 to 9.7% in 2014 vs. 3.5% to 14.8% in 2014, respectively). In adjusted models, diabetes was associated with decreased odds of return of spontaneous circulation (odds ratio 0.74 (95% confidence interval 0.66-0.82)) and 30-day survival (odds ratio 0.56 (95% confidence interval 0.48-0.65)) (interaction with calendar year p=0.434 and p=0.243, respectively).

CONCLUSION

No significant difference in temporal survival was found between the two groups. However, diabetes was associated with lower odds of return of spontaneous circulation and 30-day survival.

Out-of-hospital cardiac arrest at place of residence is associated with worse outcomes in patients admitted to intensive care. A post-hoc analysis of the targeted temperature management trial

BACKGROUND

The majority of out-of-hospital cardiac arrests (OHCAs) occur at place of residence, which is associated with worse outcomes in unselected prehospital populations. Our aim was to investigate whether location of arrest was associated with outcome in a selected group of initial survivors admitted to intensive care.

METHODS

This is a post-hoc analysis of the Targeted Temperature Management After Cardiac Arrest (TTM) trial, a multicenter controlled trial, randomizing 950 OHCA patients to an intervention of 33 °C or 36 °C. The location of cardiac arrest was defined as place of residence versus public place or other. The outcome measures were mortality and neurological outcome, as defined by the Cerebral Performance Category Scale, at 180 days.

RESULTS

Approximately half of 938 included patients arrested at place of residence (53%). Location groups did not differ with respect to age (P=0.11) or witnessed arrests (P=0.48) but bystander CPR was less common (P=0.02) at place of residence. OHCA at place of residence was associated with higher 180-day mortality (55% vs. 38%, P<0.001) and worse neurological outcome (61% vs. 43%, P<0.001) compared with a public place or other. After adjusting for known confounders, OHCA at place of residence remained an independent predictor of mortality (P=0.007).

CONCLUSIONS

Half of all initial survivors after OHCA admitted to intensive care had an arrest at place of residence which was independently associated with poor outcomes. Actions to improve outcomes after OHCA at place of residence should be addressed in future trials.

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.

Optimizing a Drone Network to Deliver Automated External Defibrillators

BACKGROUND

Public access defibrillation programs can improve survival after out-of-hospital cardiac arrest, but automated external defibrillators (AEDs) are rarely available for bystander use at the scene. Drones are an emerging technology that can deliver an AED to the scene of an out-of-hospital cardiac arrest for bystander use. We hypothesize that a drone network designed with the aid of a mathematical model combining both optimization and queuing can reduce the time to AED arrival.

METHODS

We applied our model to 53 702 out-of-hospital cardiac arrests that occurred in the 8 regions of the Toronto Regional RescuNET between January 1, 2006, and December 31, 2014. Our primary analysis quantified the drone network size required to deliver an AED 1, 2, or 3 minutes faster than historical median 911 response times for each region independently. A secondary analysis quantified the reduction in drone resources required if RescuNET was treated as a large coordinated region.

RESULTS

The region-specific analysis determined that 81 bases and 100 drones would be required to deliver an AED ahead of median 911 response times by 3 minutes. In the most urban region, the 90th percentile of the AED arrival time was reduced by 6 minutes and 43 seconds relative to historical 911 response times in the region. In the most rural region, the 90th percentile was reduced by 10 minutes and 34 seconds. A single coordinated drone network across all regions required 39.5% fewer bases and 30.0% fewer drones to achieve similar AED delivery times.

CONCLUSIONS

An optimized drone network designed with the aid of a novel mathematical model can substantially reduce the AED delivery time to an out-of-hospital cardiac arrest event.

Location of cardiac arrest and impact of pre-arrest chronic disease and medication use on survival

INTRODUCTION

Cardiac arrest in a private location is associated with a higher mortality when compared to public location. Past studies have not accounted for pre-arrest factors such as chronic disease and medication.

AIM

To investigate whether the association between cardiac arrest in a private location and a higher mortality can be explained by differences in chronic diseases and medication.

METHODS

We identified 27,771 out-of-hospital cardiac arrest patients ≥18 years old from the Danish Cardiac Arrest Registry (2001-2012). Using National Registries, we identified pre-arrest chronic disease and medication. To investigate the importance of cardiac arrest related factors and chronic disease and medication use we performed adjusted Cox regression analyses during day 0-7 and day 8-365 following cardiac arrest to calculate hazard ratios (HR) for death.

RESULTS

Day 0-7: Un-adjusted HR for death day 0-7 was 1.21 (95%CI:1.18-1.25) in private compared to public location. When including cardiac arrest related factors HR for death was 1.09 (95%CI:1.06-1.12). Adding chronic disease and medication to the analysis changed HR for death to 1.08 (95%CI:1.05-1.12). 8-365 day: The un-adjusted HR for death day 8-365 was 1.70 (95% CI: 1.43-2.02) in private compared to public location. When including cardiac arrest related factors the HR decreased to 1.39 (95% CI: 1.14-1.68). Adding chronic disease and medication to the analysis changed HR for death to 1.27 (95% CI:1.04-1.54).

CONCLUSION

The higher mortality following cardiac arrest in a private location is partly explained by a higher prevalence of chronic disease and medication use in patients surviving until day 8.

Treatment and outcome of out-of-hospital cardiac arrest in outpatient health care facilities

AIM

We evaluated the frequency and effectiveness of basic and advanced life support (ALS) interventions by medical professionals when out-of-hospital cardiac arrest (OHCA) occurred in ambulatory healthcare clinics before emergency medical services (EMS) arrival.

METHODS

Non-traumatic OHCAs in adults were systematically characterized over a 15 year period by their occurrence in clinics, at home, or in non-medical public locations, and outcomes compared between matched cohorts from each group.

RESULTS

Among 7784 patients, 6098 OHCA occurred at home, 1612 in non-medical public locations and 74 in clinics. Compared to non-medical public locations, clinic patients with OHCA were older, more often women and more frequently shocked; clinic arrests were more often witnessed, less likely to be of cardiac cause and to occur before EMS arrival. Compared to home, more clinic arrests were witnessed, occurred after EMS arrival, had bystander CPR, shockable rhythms and were defibrillated. When OHCA occurred before EMS arrival, 51 of 56 clinic patients (91%) received CPR, a defibrillator applied to 23 (41%), 17 (30%) were shocked, 4 (7%) intubated, and 7 (13%) received intravenous medications from facility personnel. Of these, only pre-EMS defibrillator use was associated with improved outcome. Among matched patients, OHCA survival was higher in clinics than at home (42% vs 26%, p=0.029), but comparable to other public locations.

CONCLUSIONS

Survival from OHCA in clinics was comparable to non-medical public locations, and higher than at home. Alongside CPR, use of defibrillators was associated with improved survival and worth prioritizing over other interventions before EMS arrival regardless of OHCA location.

Risky locations for out-of-hospital cardiopulmonary arrest in a typical urban city

Background:

The aim of this study is to clarify the circumstances including the locations where critical events resulting in out-of-hospital cardiopulmonary arrest (OHCPA) occur.

Materials and Methods:

Subjects of this population-based observational case series study were the clinical records of patients with nontraumatic and nonneck-hanging OHCPA.

Results:

Of all 1546 cases, 10.3% occurred in a public place (shop, restaurant, workplace, stations, public house, sports venue, and bus), 8.3% on the street, 73.4% in a private location (victim's home, the homes of the victims’ relatives or friends or cheap bedrooms, where poor homeless people live), and 4.1% in residential institutions. In OHCPA occurring in private locations, the frequency of asystole was higher and the outcome was poorer than in other locations. A total of 181 OHCPA cases (11.7%) took place in the lavatory and 166 (10.7%) in the bathroom; of these, only 7 (3.9% of OHCPA in the lavatory) and none in the bath room achieved good outcomes. The frequencies of shockable initial rhythm occurring in the lavatory and in bath room were 3.7% and 1.1% (lower than in other locations, P = 0.011 and 0.002), and cardiac etiology in OHCPA occurring in these locations were 46.7% and 78.4% (the latter higher than in other locations, P < 0.001).

Conclusions:

An unignorable population suffered from OHCPA in private locations, particularly in the lavatory and bathroom; their initial rhythm was usually asystole and their outcomes were poor, despite the high frequency of cardiac etiology in the bathroom. We should try to treat OHCPA victims and to prevent occurrence of OHCPA in these risky spaces by considering their specific conditions.

Basic life support knowledge, self-reported skills and fears in Danish high school students and effect of a single 45-min training session run by junior doctors; a prospective cohort study

Background

Early recognition and immediate bystander cardiopulmonary resuscitation are critical determinants of survival after out-of-hospital cardiac arrest (OHCA). Our aim was to evaluate current knowledge on basic life support (BLS) in Danish high school students and benefits of a single training session run by junior doctors.

Methods

Six-hundred-fifty-one students were included. They underwent one 45-minute BLS training session including theoretical aspects and hands-on training with mannequins. The students completed a baseline questionnaire before the training session and a follow-up questionnaire one week later. The questionnaire consisted of an eight item multiple-choice test on BLS knowledge, a four-level evaluation of self-assessed BLS skills and evaluation of fear based on a qualitative description and visual analog scale from 0 to 10 for being first responder.

Results

Sixty-three percent of the students (413/651) had participated in prior BLS training. Only 28% (179/651) knew how to correctly recognize normal breathing. The majority was afraid of exacerbating the condition or causing death by intervening as first responder. The response rate at follow-up was 61% (399/651). There was a significant improvement in correct answers on the multiple-choice test (p < .001). The proportion of students feeling well prepared to perform BLS increased from 30% to 90% (p < .001), and the level of fear of being first responder was decreased 6.8 ± 2.2 to 5.5 ± 2.4 (p < .001).

Conclusion

Knowledge of key areas of BLS is poor among high school students. One hands-on training session run by junior doctors seems to be efficient to empower the students to be first responders to OHCA.

Predictors of long-term survival after out-of-hospital cardiac arrest: the impact of Activities of Daily Living and Cerebral Performance Category scores

BACKGROUND

Current focus on immediate survival from out-of-hospital cardiac arrest (OHCA) has diverted attention away from the variables potentially affecting long-term survival.

AIM

To determine the relationship between neurological and functional status at hospital discharge and long-term survival after OHCA.

METHODS

Prospective data collection for all OHCA patients aged >18 years in the Jerusalem district (n=1043, 2008-2009).

PRIMARY OUTCOME MEASURE

Length of survival after OHCA. Potential predictors: Activities of Daily Living (ADL) and Cerebral Performance Category (CPC) scores at hospital discharge, age and sex.

RESULTS

There were 52/279 (18.6%) survivors to hospital discharge. Fourteen were discharged on mechanical ventilation (27%). Interviews with survivors and/or their legal guardians were sought 2.8±0.6 years post-arrest. Eighteen died before long-term follow-up (median survival 126 days, IQR 94-740). Six improved their ADL and CPC scores between discharge and follow-up. Long-term survival was positively related with lower CPC scores (p=0.002) and less deterioration in ADL from before the arrest to hospital discharge (p=0.001). For each point increment in ADL at hospital discharge, the hazard ratio of death was 1.31 (95%CI 1.12, 1.53, p=0.001); this remained unchanged after adjustment for age and sex (HR 1.26, 95%CI 0.07, 1.48, p=0.005).

CONCLUSIONS

One-third of the patients discharged from hospital after OHCA died within 30 months of the event. Long-term survival was associated both with better neurological and functional level at hospital discharge and a smaller decrease in functional limitation from before to after the arrest, yet some patients with a poor neurological outcome survived prolonged periods after hospital discharge.

Effect of Location of Out-of-Hospital Cardiac Arrest on Survival Outcomes

Introduction: This study aims to study how the effect of the location of patient collapses from cardiac arrest, in the residential and non-residential areas within Singapore, relates to certain survival outcomes. Materials and Methods: A retrospective cohort study of data were done from the Cardiac Arrest and Resuscitation Epidemiology (CARE) project. Out-of-hospital cardiac arrest (OHCA) data from October 2001 to October 2004 (CARE) were used. All patients with OHCA as confirmed by the absence of a pulse, unresponsiveness and apnoea were included. All events had occurred in Singapore. Analysis was performed and expressed in terms of the odds ratio (OR) and the corresponding 95% confidence interval (CI). Results: A total of 2375 cases were used for this analysis. Outcomes for OHCA in residential areas were poorer than in non-residential areas—1638 (68.9%) patients collapsed in residential areas, and 14 (0.9%) survived to discharge. This was significantly less than the 2.7% of patients who survived after collapsing in a non-residential area (OR 0.31 [0.16 – 0.62]). Multivariate logistic regression analysis showed that location alone had no independent effect on survival (adjusted OR 1.13 [0.32 – 4.05]); instead, underlying factors such as bystander CPR (OR 3.67 [1.13 – 11.97]) and initial shockable rhythms (OR 6.78 [1.95 – 23.53]) gave rise to better outcomes. Conclusion: Efforts to improve survival from OHCA in residential areas should include increasing CPR by family members, and reducing ambulance response times. Key words: Emergency Medical Services, Non-residential, Prehospital, Residential

[In-hospital resuscitation concept with first-responder defibrillation. 2-year experience]

BACKGROUND AND PURPOSE

Sudden cardiac arrest appears in 1-5 patients/ 1,000 clinical admissions. In spite of different research approaches, the prognosis after in-hospital resuscitation has not significantly improved in the last 40 years. This account presents the experiences with a hospital-wide emergency plan using the concept of defibrillation by first responders.

METHODS

In 2003, a hospital-wide emergency plan was implemented. The concept comprised the setup of 15 "defibrillator points", training of the entire hospital personnel as first responder, and the introduction of an emergency team. Over the following 3 years, the concept was optimized. In a period from May 2006 to April 2008, the data of all patients who received an in-hospital resuscitation were collected.

RESULTS

Within 24 months, a total of 41 resuscitations were conducted. Out of these, 24 patients (58%) were under intensive monitoring when the event occurred. Initially, 15 patients (36%) showed ventricular fibrillation, 15 (36%) a pulseless electrical activity, and eleven (27%) an asystoly. A total of twelve patients (29%) left hospital alive. About half of them (42%) experienced ventricular fibrillation and were under observation at the time of event.

CONCLUSION

The data collected since the implementation of the hospital- wide emergency plan in 2003 reflect the daily clinical routine. The results show that there is a better outcome especially in patients with ventricular fibrillation when receiving first-responder defibrillation.

O leigo e o suporte básico de vida

A capacitação do leigo para o atendimento precoce em situações de emergência e instituição do suporte básico de vida (SBV) é fundamental para salvar vidas e prevenir seqüelas. O objetivo foi identificar o conhecimento dos leigos sobre SBV. Utililizou-se entrevista estruturada em linguagem não-técnica. A amostra compreendeu 385 sujeitos, a maioria (57,1%) do sexo feminino com ensino médio completo e superior incompleto (53,7%). Verificou-se apenas 9,9% conhecem a manobra de respiração boca-a-boca; 84,2% conhecem a técnica de compressão torácica externa (CTE), e destes, 79,9% sabem sua finalidade. Apenas 14,5% sabem posicionar a vítima para realizar a CTE; 82,4% referem uma freqüência menor que 60 CTE/minuto. Por não apresentarem adequada informação e fundamentação das etapas do SBV, os leigos podem prestar atendimento incorreto à vítima de emergência, acarretando prejuízos à reanimação.

Long-term prognosis after out-of-hospital cardiac arrest with/without ST elevation myocardial infarction

AIM

To describe the 3-year survival of patients after out-of-hospital cardiac arrest (OHCA) taking into account the presence of ST-segment elevation myocardial infarction (STEMI) and evaluating prognostic factors associated with pre-hospital and hospital care.

PATIENT GROUP

Over a period of 29 months and with the aid of a questionnaire supplied to 24 rescue stations, we prospectively included 560 individuals (415 men; aged 16-97 years, median 68) for whom cardio-pulmonary resuscitation (CPR) for OHCA of confirmed cardiac etiology was attempted.

RESULTS

Of 149 hospitalized individuals, 28.2% survived 1 year and 25.5% survived 3 years after OHCA. In the subgroup of patients with STEMI (26 individuals; 17.5%), 57.7% survived 1 year and 53.9% survived 3 years. In the subgroup of patients without STEMI (n=123), 22% survived 1 year and 19.5% survived 3 years. The strongest predictors for long-term survival by logistic regression analysis were: age under 70 years, ventricular fibrillation as initial rhythm, CPR without atropine, and STEMI. OHCA occurrence at a public place was an indicator of better survival in the subgroup with STEMI. In the subgroup of patients without STEMI, long-term angiotensin-converting enzyme inhibitor treatment, CPR without atropine, a Glasgow Coma Scale upon hospital admission over 3, no presence of cardiogenic shock, and no manifestations of postanoxic encephalopathy (Fisher's exact test, chi(2) test) were indicators of better survival.

CONCLUSION

Among 560 individuals with "primary cardiac" etiology OHCA and initiation of professional CPR, 8% survived 1 year and 7% survived 3 years. A higher survival rate among patients with STEMI was documented.

Aspects on the increase in bystander CPR in Sweden and its association with outcome

AIM

To describe changes in the proportion of bystanders performing cardiopulmonary resuscitation (CPR) in out of hospital cardiac arrest (OHCA) in Sweden and to study the impact of bystander CPR on ventricular fibrillation and on survival during various times.

PATIENTS AND METHODS

All patients who suffered from OHCA in Sweden in whom CPR was attempted and who were included in the Swedish cardiac arrest register (SCAR) between 1992 and 2005. Crew witnessed cases were excluded.

RESULTS

In all 34,125 patients were included in the survey. Among witnessed OHCA the proportion of patients receiving bystander CPR increased from 40% in 1992 to 55% in 2005 (p<0.0001). In non-witnessed OHCA the corresponding proportion increased from 22% to 44% (p<0.0001). There was a significant increase in bystander CPR regardless of age, sex and place. The increase was only found when CPR was performed by lay persons (21% in 1992 to 40% in 2005; p<0.0001). Bystander CPR was associated with an increased proportion of patients found in a shockable rhythm and a lower number of shocks to receive return of spontaneous circulation. Bystander CPR was associated with a similar increase in survival early and late in the evaluation.

CONCLUSION

There was a marked increase in bystander CPR in OHCA, when performed by lay persons, during the last 14 years in Sweden. Bystander CPR was associated with positive effects both on ventricular fibrillation and survival.

The strong ion gap and outcome after cardiac arrest in patients treated with therapeutic hypothermia: a retrospective study

OBJECTIVE

This study investigates whether the strong ion gap (SIG) is associated with long-term outcome after cardiac arrest in patients treated with therapeutic hypothermia. The hypothesis of the study was that an elevated SIG was associated with unfavourable outcome after cardiac arrest.

DESIGN

Retrospective review of records from 1995 to 2007 of patients who received cardiopulmonary resuscitation.

SETTING

Emergency department of a university hospital.

PATIENTS

Patients who were successfully resuscitated after cardiac arrest (n = 288) and treated with mild therapeutic hypothermia.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Acid-base variables were calculated according to Stewart's approach, as modified by Figge and Fencl, and were determined immediately on admission and 12 h after the return of spontaneous circulation. Acid-base variables were determined at 37 degrees C and are reported without correction for patient temperature. Differences in SIG were compared between patients with favourable (survival 6 months with cerebral performance category 1 or 2) and unfavourable outcomes. SIG on admission and 12 h after return of spontaneous circulation was higher in patients with unfavourable outcome (n = 151; 52%). SIG 12 h after return of spontaneous circulation was identified as an independent predictor of outcome. A SIG > 8.9 mmol/L was associated with an increased cumulative hazard of death.

CONCLUSIONS

An elevated SIG 12 h after return of spontaneous circulation may be associated with unfavourable outcome in patients after cardiac arrest treated with mild therapeutic hypothermia. The unmeasured anions hidden behind an elevated SIG may represent markers of tissue damage.

Cardiac arrest in the Emergency Department: a report from the National Registry of Cardiopulmonary Resuscitation

BACKGROUND

Little is known about cardiac arrests (CA) in the Emergency Department (ED). The objective of this study was to determine the characteristics of ED CAs.

METHODS

60,852 adult, in-patient CA events in the National Registry of Cardiopulmonary Resuscitation were included. Multiple regression analysis compared ED CA with those occurring in the ICU, telemetry, or general floors. Subgroup analysis examined traumatic vs. non-traumatic ED CA and ED CA occurring after a successful pre-hospital resuscitation (recurrent) vs. primary ED event.

RESULTS

In multivariate analysis, ED location predicted improved survival to discharge (OR 0.74, 95%CI [0.67-0.82]). ED CAs had higher survival to discharge rates (ED 22.2, ICU 15.5, Tele 19.8, Floor 10.8, p<0.0001), better cerebral performance category scores (ED 1.59, ICU 1.73, Tele 1.96, Floor 1.69, p<0.0001), and shorter post-event length of stays (ED 8.6, ICU 17.5, Tele 16.5, Floor 14.2 days, p<0.0001) than other locations. Recurrent ED CAs were less likely to survive to discharge (10.1% vs. 24.6%, p<0.0001) than primary events. Trauma-related ED CAs had a lower survival to discharge rate (7.5% vs. 23.8%, p<0.0001), were less likely to be caused by an arrhythmia (23.6% vs. 32.5%, p<0.0008), and more likely to be preceded by hypotension or shock (41.6% vs. 29.0%, p<0.0001) than non-trauma ED events.

CONCLUSIONS

ED CAs have unique characteristics, and better survival and neurologic outcomes compared to other hospital locations. Primary ED CAs have a better chance of survival to discharge than recurrent events. Traumatic ED CAs have worse outcomes than non-traumatic CA.

Teaching basic life support to school children using medical students and teachers in a 'peer-training' model--results of the 'ABC for life' programme

BACKGROUND

The 'ABC for life' programme was designed to facilitate the wider dissemination of basic life support (BLS) skills and knowledge in the population. A previous study demonstrated that using this programme 10-12-year olds are capable of performing and retaining these vital skills when taught by medical students. There are approximately 25,000 year 7 school children in 900 primary schools in Northern Ireland. By using a pyramidal teaching approach involving medical students and teachers, there is the potential to train BLS to all of these children each year.

AIMS

To assess the effectiveness of a programme of CPR instruction using a three-tier training model in which medical students instruct primary school teachers who then teach school children.

SETTINGS

School children and teachers in the Western Education and Library Board in Northern Ireland.

METHODS

A course of instruction in cardiopulmonary resuscitation (CPR)--the 'ABC for life' programme--specifically designed to teach 10-12-year-old children basic life support skills. Medical students taught teachers from the Western Education and Library Board area of Northern Ireland how to teach basic life support skills to year 7 pupils in their schools. Pupils were given a 22-point questionnaire to assess knowledge of basic life support immediately before and after a teacher led training session.

RESULTS

Children instructed in cardiopulmonary resuscitation using this three-tier training had a significantly improved score following training (57.2% and 77.7%, respectively, p<0.001).

CONCLUSION

This study demonstrates that primary school teachers, previously trained by medical students, can teach BLS effectively to 10-12-year-old children using the 'ABC for life' programme.