• Ambulance telephone triage using 'NHS Pathways' to identify adult cardiac arrest

      Deakin, Charles D.; England, Simon; Diffey, Debbie (2017-05)
      Background UK ambulance services are called to 30 000 cardiac arrests (CAs) annually where resuscitation is attempted. Correct identification by the ambulance service trebles survival by facilitating bystander-cardiopulmonary resuscitation (CPR) and immediate ambulance dispatch. Identification of CA by telephone is challenging and involves algorithms to identify key features. ‘NHS Pathways’ is now used for triage by six of 12 UK ambulance services, covering a population of 20 million. With the significant improvements in survival when CA is accurately identified, it is vital that ‘NHS Pathways’ is able to identify CA correctly. Methods All ‘999’ emergency calls to South Central Ambulance Service (SCAS) over a 12-month period screened by NHS Pathways v9.04 were identified. All actual or presumed CAs identified by the emergency call taker were cross-referenced with the ambulance crew’s Patient Report Form to identify all confirmed CAs. Results A total of 469 400 emergency (999) calls were received by SCAS. Of the 3119 CA identified by ambulance crew, 753 were not initially classified as CA by NHS Pathways (24.1%). Overall, sensitivity=0.759 (95% CI 0.743 to 0.773); specificity=0.986 (95% CI 0.9858 to 0.98647); and positive predictive value=26.80% (95% CI 25.88 to 27.73%). Conclusions NHS Pathways accurately identifies 75.9% of adult CAs. The remainder represents approximately 7500 treatable CAs in the UK annually where the diagnosis is missed, with significant implications for patient outcome. Further work is required to improve this first link in the chain of survival https://heart.bmj.com/content/heartjnl/103/10/738.2.full.pdf This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/ http://dx.doi.org/10.1136/heartjnl-2016-310651
    • Public access defibrillation remains out of reach for most victims of out-of-hospital sudden cardiac arrest

      Deakin, Charles D.; Shewry, Elizabeth; Gray, Huon H. (2014-04)
      Introduction Public access defibrillation (PAD) prior to ambulance arrival is a key determinant of survival from out-of-hospital (OOH) cardiac arrest. Implementation of PAD has been underway in the UK for the past 12 years, and its importance in strengthening the chain of survival has been recognised in the government's recent ‘Cardiovascular Disease Outcomes Strategy’. The extent of use of PAD in OOH cardiac arrests in the UK is unknown. We surveyed all OOH cardiac arrests in Hampshire over a 12-month period to ascertain the availability and effective use of PAD. Methods A retrospective review of all patients with OOH cardiac arrest attended by South Central Ambulance Service (SCAS) in Hampshire during a 1-year period (1 September 2011 to 31 August 2012) was undertaken. Emergency calls were reviewed to establish the known presence of a PAD. Additionally, a review of all known PAD locations in Hampshire was undertaken, together with a survey of public areas where a PAD may be expected to be located. Results The current population of Hampshire is estimated to be 1.76 million. During the study period, 673 known PADs were located in 278 Hampshire locations. Of all calls confirmed as cardiac arrest (n=1035), the caller reported access to an automated external defibrillator (AED) on 44 occasions (4.25%), successfully retrieving and using the AED before arrival of the ambulance on only 18 occasions (1.74%). Conclusions Despite several campaigns to raise public awareness and make PADs more available, many public areas have no recorded AED available, and in those where an AED was available it was only used in a minority of cases by members of the public before arrival of the ambulance. Overall, a PAD was only deployed successfully in 1.74% OOH cardiac arrests. This weak link in the chain of survival contributes to the poor survival rate from OOH cardiac arrest and needs strengthening. https://heart.bmj.com/content/heartjnl/100/8/619.full.pdf This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/ http://dx.doi.org/10.1136/heartjnl-2013-305030
    • Public knowledge and confidence in the use of public access defibrillation.

      Brooks, Ben; Chan, Stephanie; Lander, Peter; Adamson, Robbie; Hodgetts, Gillian A.; Deakin, Charles D. (2015-06)
      https://heart.bmj.com/content/101/12/967.long Introduction Growing numbers of public access defibrillators aim to improve the effectiveness of bystander cardiopulmonary resuscitation prior to ambulance arrival. In the UK, however, public access defibrillators are only deployed successfully in 1.7% of out-of-hospital cardiac arrests. We aimed to understand whether this was due to a lack of devices, lack of awareness of their location or a reflection of lack of public knowledge and confidence to use a defibrillator. Methods Face-to-face semistructured open quantitative questionnaire delivered in a busy urban shopping centre, to identify public knowledge relating to public access defibrillation. Results 1004 members of the public aged 9–90 years completed the survey. 61.1% had been first aid trained to a basic life support level. 69.3% claimed to know what an automatic external defibrillator was and 26.1% reported knowing how to use one. Only 5.1% knew where or how to find their nearest public access defibrillator. Only 3.3% of people would attempt to locate a defibrillator in a cardiac arrest situation, and even fewer (2.1%) would actually retrieve and use the device. Conclusions These findings suggest that a lack of public knowledge, confidence in using a defibrillator and the inability to locate a nearby device may be more important than a lack of defibrillators themselves. Underused public access defibrillation is a missed opportunity to save lives, and improving this link in the chain of survival may require these issues to be addressed ahead of investing more funds in actual defibrillator installation. https://heart.bmj.com/content/101/12/967.long This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/ http://dx.doi.org/10.1136/heartjnl-2015-307624
    • Underutilisation of public access defibrillation is related to retrieval distance and time-dependent availability

      Deakin, Charles D.; Anfield, Steve; Hodgetts, Gillian A. (2018-08)
      Introduction Public access defibrillation doubles the chances of neurologically intact survival following outof-hospital cardiac arrest (OHCA). Although there are increasing numbers of defibrillators (automated external defibrillator (AEDs)) available in the community, they are used infrequently, despite often being available. We aimed to match OHCAs with known AED locations in order to understand AED availability, the effects of reduced AED availability at night and the operational radius at which they can be effectively retrieved. Methods All emergency calls to South Central Ambulance Service from April 2014 to April 2016 were screened to identify cardiac arrests. Each was mapped to the nearest AED, according to the time of day. Mapping software was used to calculate the actual walking distance for a bystander between each OHCA and respective AED, when travelling at a brisk walking speed (4 mph). Results 4012 cardiac arrests were identified and mapped to one of 2076 AEDs. All AEDs were available during daytime hours, but only 713 at night (34.3%). 5.91% of cardiac arrests were within a retrieval (walking) radius of 100m during the day, falling to 1.59% out-of-hours. Distances to rural AEDs were greater than in urban areas (P<0.0001). An AED could potentially have been retrieved prior to actual ambulance arrival in 25.3% cases. Conclusion Existing AEDs are underused; 36.4% of OHCAs are located within 500m of an AED. Although more AEDs will improve availability, greater use can be made of existing AEDs, particularly by ensuring they are all available on a 24/7 basis. https://heart.bmj.com/content/heartjnl/104/16/1339.full.pdf This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/ http://dx.doi.org/10.1136/heartjnl-2018-312998