Use of a geographic information system to identify differences in automated external defibrillator installation in urban areas with similar incidence of public out-of-hospital cardiac arrest: a retrospective registry-based study

Abstract

ObjectivesEarly defibrillation in out-of-hospital cardiac arrest (OHCA) is of importance to improve survival. In many countries the number of automated external defibrillators (AEDs) is increasing, but the use is low. Guidelines suggest that AEDs should be installed in densely populated areas and in locations with many visitors. Attempts have been made to identify optimal AED locations based on the incidence of OHCA using geographical information systems (GIS), but often on small datasets and the studies are seldom reproduced. The aim of this paper is to investigate if the distribution of public AEDs follows the incident locations of public OHCAs in urban areas of Stockholm County, Sweden.MethodOHCA data were obtained from the Swedish Register for Cardiopulmonary Resuscitation and AED data were obtained from the Swedish AED Register. Urban areas in Stockholm County were objectively classified according to the pan-European digital mapping tool, Urban Atlas (UA). Furthermore, we reclassified and divided the UA land cover data into three classes (residential, non-residential and other areas). GIS software was used to spatially join and relate public AED and OHCA data and perform computations on relations and distance.ResultsBetween 1 January 2012 and 31 December 2014 a total of 804 OHCAs occurred in public locations in Stockholm County and by December 2013 there were 1828 AEDs available. The incidence of public OHCAs was similar in residential (47.3%) and non-residential areas (43.4%). Fewer AEDs were present in residential areas than in non-residential areas (29.4% vs 68.8%). In residential areas the median distance between OHCAs and AEDs was significantly greater than in non-residential areas (288 m vs 188 m, p<0.001).ConclusionThe majority of public OHCAs occurred in areas classified in UA as ‘residential areas‘ with limited AED accessibility. These areas need to be targeted for AED installation and international guidelines need to take geographical location into account when suggesting locations for AED installation.

Prehospital cardiopulmonary resuscitation duration and neurological outcome after adult out-of-hospital cardiac arrest by location of arrest

“…Previous studies showed that public access AEDs and/or bystander CPR were more effective in public locations than in residential locations. 8,15–17 In this study on prehospital CPR duration, patients with OHCA that occurred in public locations also had a higher proportion of one-month survival with favourable neurological outcome than those that occurred in residential locations. The predictive probability of favourable neurological outcome showed a higher proportion in public locations than in residential locations at any given time.…”

“…Previous studies showed that public access AEDs and/or bystander CPR were more effective in public locations than in residential locations. 8,[15][16][17] In this study on prehospital CPR duration, patients with Figure 2. Non-linear relationship between the prehospital CPR duration and predictive probability of favourable neurological outcome using predictive margins in the univariable logistic regression model.…”

“…The differences in the OHCA outcome by the location of arrest would be explained by prognostic factors for OHCA patients. 15,17,23,24 Indeed, patients with OHCA that occurred in public locations were more likely to be younger, witnessed by bystanders and received bystander interventions compared with those in residential locations. Thus, as patients with OHCA that occurred in public locations had many good prognostic factors, they would attain a high one-month survival rate with favourable neurological outcome regardless of the length of prehospital CPR duration, which suggests that resuscitation efforts should continue for a long time in the case of OHCA that occurs in public locations.…”

“…9,10 In previous studies on cardiopulmonary resuscitation (CPR) duration, the possibility of survival with favourable neurological outcome was almost zero when the CPR duration exceeded 40-45 minutes [11][12][13][14] in adult patients with OHCA. Importantly, patient and EMS characteristics and outcomes of adult patients with OHCA differed by the location of arrest, [15][16][17] but the association between CPR duration for adult patients with OHCA and the location of arrest has not been sufficiently investigated.…”

Public awareness about the use of automatic external defibrillator (AED) in giving first aid

“…In Poland, like in other highly developed countries, the number of automated external defibrillators is constantly growing. They are being deployed, for example, in trains, at railway stations, in churches, sports venues, catering and entertainment facilities and in various other places [24,26]. Unfortunately, as the authors' own research and that of the other authors showed, the public awareness of what these devices really are, where to find them or how to use them, is still low and therefore, continuing education in this area needs to be provided.…”