Medical science did humanity a big favour when it invented the automated external defibrillator (AED). The AED is a straightforward device that delivers controlled electrical shocks to resuscitate a person suffering from cardiac arrest. They are so easy to use in the 21st century that a person can save a life with an AED despite not having any formal medical training.
With all that said, some experts recommend combining AED's with cardiopulmonary resuscitation (CPR) techniques. But why? Are AED's best when used in conjunction with CPR? A limited amount of data seems to suggest this is so. For example, consider a study published in the Transactions of the American Clinical and Climatological Association journal in 2011.
Studying Chest Compressions for Resuscitation
When the study was originally done, the types of AED's now on the market were not widely used. Furthermore, data utilised by researches was, in some cases, more than a decade old. Chest compressions were still considered the best way to keep cardiac arrest patients alive until they received professional medical care. The researchers who conducted the study were interested in understanding the benefits of AED's and CPR used together.
They began with a premise based on the American Heart Association's 'chain of survival'. This chain of survival emphasises the importance of chest compressions in keeping cardiac arrest patients alive – with or without electric shock.
Researchers noted that AED's utilised aboard aircraft at the time increased the chances of long-term survival among cardiac arrest patients to 40%. Their data revealed that allowing three sets of shocks from an AED before reviving chest compressions only slowed patient responses, meaning a longer delay before resuscitation was actually achieved. Conversely, when the first shock was immediately followed by chest compressions, the rate of resuscitation – meaning conversion of ventricular rhythm to sinus rhythm – was 85%.
This led to the conclusion that combining AED's with CPR yields better results than relying on either single method alone. Their findings further suggest that CPR training is still a wise idea among the general population.
More Training is Necessary
Research data seems to suggest that any strategies designed to get people more involved in learning how to respond to cardiac arrest should include discussions of CPR training. This includes government advice relating to AED's and resuscitation for the UK. We should be advising people to undergo CPR training rather than implying they don't need it now that AED's are showing up in public places.
In relation to that point, data released in 2018 shows that approximately 30% of UK adults are unwilling or unlikely to perform CPR on behalf of someone suffering from cardiac arrest. The reasons are limited to just two:
· They have never received any kind of CPR training; or
· They have been trained but do not remember what they learned.
We know that just 10% of those who suffer an out-of-hospital cardiac arrest and do not receive CPR or electric shock go on to survive. By contrast, cardiac arrest victims in countries where CPR is taught in school have a significantly higher survival rate of 25%. It is numbers like these that make the case for nationwide CPR training today.
Time is of the Essence
Cardiac arrest is a situation in which a person's heart has physically stopped beating. It is an obvious medical emergency. Within the first three minutes following the onset of cardiac arrest, brain tissue begins dying. Heart and other tissues soon follow. It only takes a few more minutes to claim the patient's life.
Time is of the essence when it comes to dealing with cardiac arrest. Furthermore, administering CPR doubles a person's chances of survival. Combining CPR with AED use makes for even better results. It should be obvious that we need to be pushing new CPR training along with AED awareness.
The best thing about AED's is that they do not require formal training to use. Even without CPR training, no one need be afraid to unpack an AED device, connect it to the patient, and turn it on. The AED can do most of the heavy lifting by itself.
Someone who does have CPR training can enhance an AED's capabilities by administering chest compressions immediately after the first shock. The general rule, according to the previously mentioned 2011 study, is to apply chest compressions for a full three minutes following the first shock. Then you stop and allow the AED to monitor for a heartbeat. If necessary, another shock is delivered followed by additional chest compressions.
Let's Push for Both
Are AED's best when used in conjunction with CPR? The data seems to suggest as much. Thus, it seems there is little benefit in having an either-or discussion. It is not about CPR being better than AED's or vice-versa. Let us push for both as a combined means of increasing survival rates among cardiac arrest victims.