Cardio Pulmonary Resuscitation (more commonly known as CPR), is a method employed to manually maintain the circulation of oxygenated blood to the body’s vital organs, with the goal of staving off major organ damage during the event of an out of hospital cardiac arrest.
What are the differences between Conventional CPR and Hands only?
When delivering CPR, there are 2 methods which you could potentially deploy on the victim of the cardiac arrest.
The first and most traditional method is ‘conventional CPR’.
Conventional CPR is a combination of chest compressions and ‘mouth to mouth’ breaths.
When delivering conventional CPR, you manually circulate blood around the body which mimics the pumping of the heart by interlocking your fingers, placing the heels of your palms firmly into the patient’s chest and pressing down repeatedly and quickly. This is accompanied with breaths or ‘mouth to mouth’, where you open-up the patient’s airways and use your own breathing to introduce more oxygen into the body.
The second method that can be used is ‘Hands only CPR’.
Hands only CPR is only the use of the chest compression aspects of conventional CPR; pushing hard and fast on the chest to a rhythm without giving rescue breaths.
Why are there two separate methods?
The reason for using two separate methods of CPR is down to the ‘mouth to mouth’ aspect.
In a cardiac arrest, when you don’t know the casualty, some people may be sceptical of placing their mouth onto another person’s and breathing into their body, be it because of the spread of germs, religious reasons or stage fright.
This led to a belief that advising the use of compression only CPR was the best option when addressing an out of hospital cardiac arrest. Major organisations have stressed that it is better to perform any form of CPR be it chest compressions only, than nothing. This was done to promote the idea that in emergency don’t be a bystander, anyone can perform a potentially life-saving act. but as the problems with the ‘mouth to mouth’ aspect conventional CPR rose, public ideology had to be changed to give anyone in such a state, a chance of survival.
This has left a question in the minds of researchers; which method is more effective?
Several studies have been conducted over the years in attempts to reinforce or change guidelines on methodology for CPR and the results are constantly conflicting. For example, in 2008, three American studies led to the guidelines being changed to advise the use of hand only CPR.
This study identified that in previous randomised trials, the survival rate (to hospital discharge) was 13.3% for compression only CPR as opposed to 7.2% for conventional CPR. No mention is made of the time that it took for CPR to be administered in each case.
As previously mentioned, compression only began to be promoted to educate the public not to stand by in case of emergency, whether they have full CPR training or not. The Vinnie Jones’ ‘staying alive’ advert started to raise awareness with regards to the fact that some intervention is better than none.
But in the medical community perceptions were beginning to change. Organisations like the British Heart Foundation backed the Vinnie Jones advert this but made sure they reiterated that this is because it is a simpler method and encouraged people to act but it was perhaps not as effective as conventional CPR. The immediate initiation of bystander CPR can double or quadruple survival from out-of-hospital cardiac arrest. Despite this compelling evidence, only 40% of victims receive bystander CPR in the UK.
Respiration is the reason this is so key. Using chest compression’s can only push around the oxygenated blood acquired from aerobic respiration prior to the person becoming unconscious and stopping breathing. Once the body begins to lose oxygen and carbon dioxide becomes more prevalent in the blood due to the person stopping breathing, the major organs then begin to shut down. Opening the airways of the unconscious casualty and manually oxygenating their blood for them would should lead to a greater chance of survival.
An article in the BMJ references the SOS-KANTO study from 2011; a study of 4068 patients suffering witnessed cardiac arrests in Japan that concluded conventional CPR was superior based on the neurological survival that incurs from not re-oxygenating the blood. This was particularly true in younger patients, or when initiating CPR after the cardiac arrest was delayed.
The Resus Council guidelines, summarising the ILCOR 2015 Guideline, state that if trained and able, thirty chest compression’s should be combined with two rescue breaths.
There are still people that continue to argue that compression only CPR is the best option, such as this article by Pacific Medical
However, in all First Aid Courses in the UK since January 2017, the use of AED’s is now part of the course, as is compression and rescue breath CPR.
The absolute conclusion that cannot be argued, is that doing something, is better than nothing. You can’t kill anyone, and you may just save a life. Would you rather be a possible hero, or a bystander?