It takes a system to save a life: Improving survival from cardiac arrest.

By Professor Tony Walker ASM FACPara

Around 25,000 people suffer a cardiac arrest across Australia and New Zealand (ANZ) each year. Around 12% survive a cardiac arrest with higher rates of survival for those in a shockable rhythm.

Despite their homogeneity, there are differences in cardiac arrest survival between the various ANZ ambulance services, however this gap is progressively narrowing as each service focuses on best practice improvement strategies.

Australia has a history of innovation in cardiac arrest going back to the early 1970s with the introduction of mobile coronary care ambulances in Victoria and New South Wales and portable defibrillation into primary ambulance clinical practice across Australia in the late 1980s and early 1990s.

The move to thinking about cardiac arrest through a systems lens started with the development of the Chain of Survival in the early 1990s1. This approach recognised improved cardiac arrest survival where a particular sequence of interlinked events occurred as quickly as possible; in particular, early activation of the EMS system, performance of bystander CPR and rapid delivery of defibrillation. The Chain of Survival concept has continued to evolve and become the mainstay of cardiac arrest system improvement since then.

Ambulance Victoria (AV) provides a unique case study to explore how focusing on system improvement by strengthening the Chain of Survival improves outcomes. Following a 1998 study in Melbourne which found low levels of bystander CPR (22%) and only 3% survival to hospital discharge (9% where the patient was in a shockable rhythm)2, AV received $3M annual recurrent funding from the Victorian Government to implement a Pre-Ambulance Basic Life Support Strategy (PABLS) to strengthen the Chain of Survival.

Initiatives introduced included a cardiac arrest registry and annual report to the community, Public Access Defibrillation, firefighter co-responder and community first responder programs and a DVD based CPR awareness program for those aged over 50 years. The implementation of the PABLS strategy and other subsequent improvements led to an increase in bystander CPR rates from 35% in 20023 to 79% in 2021-224 and an 80% improvement in the odds of survival to hospital discharge for patients presenting in a shockable rhythm in 2021-2022 compared to 2006-074

Seattle in the United States commenced their Medic One program in the early 1970s and since then, their continued focus on cardiac arrest improvement has seen them universally recognised as world leaders in cardiac arrest survival. In 2008 they commenced the first Resuscitation Academy (RA) to share their experiences and help other EMS services learn how to develop and implement plans to improve survival. Based on the successes of the RA, a meeting was held at the Utstein Abbey in Norway in 2015 to explore opportunities to expand the international reach and utility of the RA concept around the world. This meeting led to the establishment of the Global Resuscitation Alliance (GRA) and the publication of a paper5 outlining ten programs (best practices) to achieve improvement underpinned by the principles of “measure and improve”.

As the Secretariate of the GRA in ANZ, the Council of Ambulance Authorities has regularly hosted RA forums involving local and international experts to help disseminate information on the ten programs and share local best practice. Each ambulance service’s cardiac arrest system of care is at a different stage of maturity and the ten programs have provided a framework to successfully help guide local improvement. Victoria, with a mature cardiac arrest system of care, has focused amongst other things on high-performance CPR (which saw a 33% increase in the risk-adjusted odds of survival)6, implementing GoodSAM, a smart phone app connecting almost 6,000 registered users with someone nearby in cardiac arrest, and trialling whether equipping highfrequency GoodSAM responders with an ultraportable defibrillator (CellAED) can increase survival. Over the same period the Australian Resuscitation Outcomes Consortium (AusROC) established a national Epistry (Epidemiological Registry) with 100% Australia and New Zealand coverage allowing the reporting and comparison of Out of Hospital Cardiac Arrest across the region for the first time6

There have been significant advances in cardiac arrest care in Australia over the past 50 years and a growing understanding of the benefits that can be realised by looking at cardiac arrest through the lens of a data and improvement driven system of care. This approach is already paying dividends across Australia and new technologies such the GoodSAM app and ultraportable AEDs create new opportunities to further strengthen our cardiac arrest systems of care and, as Prof Mickey Eisenberg puts it, “Snatch more lives from the jaws of death”.

ASM FACPara

1. Cummins RO, Ornato JP, Theis W, et al. Improving survival from cardiac arrest: the chain of survival concept Circulation 1991: 83: 1832-1847.

2. Bernard S. Outcome from prehospital cardiac arrest in Melbourne, Australia. Emerg Med 1998; 10: 25-29.

3. Smith K, Currell A, Walker T, et al. A pre-ambulance basic life support (PABLS) strategy in Victoria, Australia Resuscitation: 2010: 81S; S1–S114

4. Ambulance Victoria 2023. Victorian Ambulance Cardiac Arrest Registry 2021–2022 Annual Report. Accessed 6 July 2023. <ambulance.vic.gov.au/about-us/ research/research-publications/>.

5. Eisenberg M, Lippert F, Castren M, et al. 2018. Improving Survival from Out-of-Hospital Cardiac Arrest. Acting on the Call 2018 Update from the Global Resuscitation Alliance. Accessed 6 July 2023. <globalresuscitationalliance.org/ wp-content/pdf/acting_on_ the_call.pdf> .

6. Bray J, Howell S, Ball S, et al. The epidemiology of out-ofhospital cardiac arrest in Australia and New Zealand: A binational report from the Australasian Resuscitation Outcomes Consortium (Aus-ROC) Resuscitation. 2022: Mar;172:74-83.