Is a 10% survival rate from cardiac arrest acceptable?

Out of Hospital Cardiac arrest (OHCA) – Call, Push, Shock….

Like many other people in Australia, I have been taking in the sad news of cricketing icon Shane Warne’s sudden passing. Then a few days ago hearing about the Foo Fighters drummer, Taylor Hawkin’s death, made me think about revisiting this important topic.

Considering I am a similar age to both men, it brought home my own mortality, as someone who is a registered paramedic, a fit person (according to Garmin), generally healthy and carry a defibrillator in my car (not used in anger yet). So, what can we collectively do to improve sudden cardiac arrest outcomes in our communities and how can we play our part?

Reading the below cardiac arrest survival (SCA) statistics is not exactly overly stimulating or encouraging, however, within this global data set are trends we should be excited about.

Table 1 – Global survival data from sudden cardiac arrest (1)

An example of this is reflected in the next table which demonstrates some of the amazing progress being made in addressing SCA survival in communities in Denmark, Soul Korea and Seattle USA.

Table 2 – Survival from out-of-hospital cardiac arrest per 100,000 of population in Seattle, Denmark, and Seoul (2)

Table 3 – OHCA outcomes for cases that received an attempted resuscitation by emergency medical services in 2019. (3)

As you will note from table 3, Australia and New Zealand are doing a fantastic job but clearly there are many more lives that can be saved! Have a look at the bottom of the table for the bystander witnessed, shockable rhythm, Survival to hospital discharge 30 days, including AED and ROSC, prior to EMS arrival. The data is really encouraging.

Background:

The incidence of emergency medical services managed out of hospital cardiac arrest (OHCA) has been reported as 40.6 per 100,000 person-years in Europe, 47.3 in North America, 45.9 in Asia, and 51.1 in Australia or 16,500 sudden cardiac arrests per day globally (compare to table 2). Patient outcomes after OHCA vary substantially by region but are generally poor, suggesting opportunities for improvement. (4)

The “chain of survival” is now a universally accepted series of actions laypeople can use in OHCA settings to address the management of a person experiencing a sudden cardiac arrest (SCA). More recently, the Call-Push-Shock (CPS) mantra has evolved, which is a national collaborative movement co-sponsored by Parent Heart Watch (PHW) and Sudden Cardiac Arrest (SCA) Foundation (SCAF) in the USA and is being adopted globally.

Remember “Saving lives matters” so please read on, as this is important and could literally save your life or that of a loved one! Remember, knowledge is power.

Below is an infographic snapshot from the New South Wales Ambulance Service “Out of hospital cardiac arrest” Annual report for 2019. (5)

What should stand out are the following 3 indicators, which are common across most Australian states and territories:

Survival to discharge is 12%
76% of sudden cardiac arrests (SCA) events occur at a private residence
63% are witnessed by a by stander

The below table demonstrates that around 8% of people survive to discharge if their SCA occurs at a private residence, compared to public/other locations, which places survival at around 20%. (6)

An 8% survival rate may not come as a surprise to many people. Likely contributing factors to poor outcomes are; Ambulance response times, a need for greater CPR public awareness initiatives/training and a lack of onsite/community defibrillators. This represents a significant opportunity to do more and to save many more lives!

The following study represented in the infographic below, stands out as a model of success demonstrating clear progress in saving lives through increased community CPR education, bystander CPR and early AED use. (7)

This study has demonstrated a significant and positive impact on survival to discharge over the 13 year period, with three times as many positive survival outcomes being achieved over a 3 year period!

Three times, that is significant!

Response times

Now, let’s consider ambulance response times (getting on scene). The following information should be a cause for concern (zero fault attributed to the ambulance services or paramedics) due to the importance of getting advance care to the SCA patient in a timely manner.

Australian Ambulance Services (8)

In 2020-21, the time within which 50 per cent of first responding ambulance resources arrived at the scene of an emergency in code 1 situations:

In capital cities ranged from 9.0 to 13.8 minutes, increasing to between 14.7 to 34.4 minutes for 90 per cent to respond.

State-wide ranged from 9.0 and 14.0 minutes, increasing to between 14.7 to 33.4 minutes for 90 per cent to respond.

Bearing in mind how busy the roads are especially in metropolitan areas, these response times are impressive, also when you take the size and scale of rural and remote Australia into consideration. But the key here is recognising that it will take a minimum of 14 minutes to get a team of highly skilled clinicians to the patient.

Let’s situate the discussion (Gets a little spicy here)

What do we want? A shockable rhythm please!

In a perfect world, we want our SCA victim to be in a shockable rhythm when we apply an AED. About 24% of patients are initially likely to be in a shockable rhythm, such as ventricular fibrillation (VF). Evidence suggests that there are 3 phases to a VF rhythm in a SCA, which are worth reflecting on:

Electrical phase (Initial 0-4 minutes, where the patient may be in a shockable rhythm and defibrillation can be effective) Bystander maximum IMPACT using an AED if available, in tandem with CPR.
Circulatory phase (5-10 minutes – high quality CPR can potentially extend the period of time a patient remains in a shockable rhythm, until a defibrillator arrives) Bystander maximum IMPACT
Metabolic phase (> 10 minutes – This is the phase where we absolutely need a clinical team to help reverse the causes of the cardiac arrest, using drug therapies, advanced airway management, oxygen, in conjunction with CPR/defibrillation or electrical therapy) This is where our highly trained and skilled PARAMEDICS really come into their own

Learning outcomes

What we can learn from the above is that in an out of hospital setting it is critical to (Call-Push-Shock) initiate CPR and get an AED to the patient as quickly as possible. If a patient is in a shockable rhythm (potentially in the first 4 minutes, with quality CPR it extends the time window), however, an AED is the only definitive way to revert someone who is in a shockable rhythm (assuming cardiac etiology), back into a perfusible rhythm (have a detectable pulse).

Remember, quality CPR can extend the window of a shockable rhythm, provide vital oxygen and blood flow to the brain and vital organs, while giving the patient the best opportunity for return of spontaneous circulation. So, if we have been doing outstanding CPR, and paramedics arrive, the patient will still have a fantastic chance of survival because you have likely extended that shockable rhythm window.

Remember, the first minutes really do matter in SCA.

Much work has been done to advocate for increased access to free public CPR training, including lobbying for public access defibrillators in the community. This progress is fantastic, but more needs to be done!

What we know:

Survival rates from sudden cardiac arrest (SCA) are as low as 10% in most countries
Most prehospital SCA events happen at a private residence
Most public defibrillators are located at sporting, public or business venues (large shopping centers, airports)
In 90% of code 1 responses the average ambulance service response time from the initial call, to being on scene across Australia, ranges from 14.7 minutes to 33.4 minutes statewide
A cardiac arrest patient hospital stay (assuming survival to discharge) will cost a minimum of $30,000 (9)

Next steps:

Increase FREE public CPR/AED education, especially focusing on residential settings and schools to K12
Domestic home building, car and transport industries should invest in public access AED’s and CPR education programs, every new car should come with an AED and first aid kit (Combo)
- Australia sold just over 1 million new cars in 2021
- Globally over 58 million new cars were sold in 2021
- Police services are starting to carry AEDs in their vehicles (Great initiative)
Apartments or high density/high rise buildings should also have a public access defibrillators installed as part of the planning and building process
Continue to invest in and build, community-based CPR/AED education programs – Find philanthropic sponsors
The cost of a defibrillator is as little as $1,000 (soon to change) versus, losing a loved one
The on cost to the health care system and government per SCA event, is a minimum of $30,000, assuming the patient makes it home!
Sign up to the Good Sam app in Australia via the App store or Play store

Find a way to gain access to a community group who provide CPR training or set one up and fundraise for your community program. There are some great innovations happening in the AED and training markets today.

I recently came across this really well priced AED called CellAED. It is an innovative, low-cost AED, as well as being small and highly mobile, it was developed right here is Australia by the partner of a SCA survivor: https://rapidresponserevival.com/

Anyway, stay safe during these challenging times and look after yourself and play your part.

References