Mobile phone technology identifies and recruits trained citizens to perform CPR on out-of-hospital cardiac arrest victims prior to ambulance arrival

Abstract

Aim

In a two-parted study, evaluate a new concept were mobile phone technology is used to dispatch lay responders to nearby out-of-hospital cardiac arrests (OHCAs).

Methods

Mobile phone positioning systems (MPS) can geographically locate selected mobile phone users at any given moment. A mobile phone service using MPS was developed and named Mobile Life Saver (MLS). Simulation study: 25 volunteers named mobile responders (MRs) were connected to MLS. Ambulance time intervals from 22 consecutive OHCAs in 2005 were used as controls. The MRs randomly moved in Stockholm city centre and were dispatched to simulated OHCAs (identical to controls) if they were within a 350 m distance. Real life study: during 25 weeks 1271–1801 MRs trained in CPR were connected to MLS. MLS was activated at the dispatch centre in parallel with ambulance dispatch when an OHCA was suspected. The MRs were dispatched if they were within 500 m from the suspected OHCA.

Results

Simulation study: mean response time for the MRs compared to historical ambulance time intervals was reduced by 2 min 20 s (44%), p < 0.001, (95% CI, 1 min 5 s – 3 min 35 s). The MRs reached the simulated OHCA prior to the historical control in 72% of cases. Real life study: the MLS was triggered 92 times. In 45% of all suspected and in 56% of all true OHCAs the MRs arrived prior to ambulance. CPR was performed by MRs in 17% of all true OHCAs and in 30% of all true OHCAs if MRs arrived prior to ambulance.

Conclusion

Mobile phone technology can be used to identify and recruit nearby CPR-trained citizens to OHCAs for bystander CPR prior to ambulance arrival.

Introduction

Survival from out-of-hospital cardiac arrest (OHCA) is generally low, about 5–10%, with the exception of a few controlled settings (casinos, airports and some cities).1, 2 The poor prognosis of OHCA is mainly explained by long time intervals between cardiac arrest, cardiopulmonary resuscitation (CPR) and defibrillation.³ To increase bystander actions and to decrease time to defibrillation substantial resources have been put into CPR educational campaigns and in recent years into the spread of automated external defibrillators (AEDs) in public venues.⁴ Still, the vast majority of the public with CPR training will never use their skills in real life and most public AEDs will never be deployed.⁵ Mobile phone technology offers the possibility to locate single mobile phone users at any given moment. If designated lay responders immediately can be identified and recruited to the scene of nearby suspected OHCAs bystander CPR, CPR quality and the use of public access AED might be increased.

The aim of this paper is to describe how mobile phone technology and mobile positioning systems (MPS) can be used to identify lay responders and recruit them to the scene of nearby OHCAs prior to ambulance [emergency medical responders (EMS)] arrival. This paper describes the PILOT-part (focus on technological potentiality and time cuts in cardiac arrest treatment) of the RUMBA (Response to Urgent Mobile Message for Bystander Activation)-project. The RUMBA-project has an overall purpose of increasing survival after OHCA in Stockholm by the activation of CPR-trained citizens and mobilisation of public defibrillators.