CHAMPIONING OUR COMMuNITY

The letters CPR stand for cardiopulmonary resuscitation. The term embraces all the procedures from basic first aid to the most advanced medical interventions that can be used to restore the breathing and circulation in someone whose heart and breathing have stopped.

For lay people and first aiders, CPR refers to the basic first aid procedures that can be used to keep someone alive until the emergency medical services can get to the scene. The most important skills are chest compressions to pump blood around the body.

Cardiac arrest means that the heart has stopped pumping blood around the body. This may occur for many reasons, but loss of the electrical co-ordination that controls the normal heartbeat is usually responsible. 

The most likely cause is ventricular fibrillation, in which the normal orderly electrical signal that controls the heartbeat becomes completely disorganised and chaotic, and the heart is unable to act as a pump. Ventricular fibrillation can be treated with a defibrillator that delivers a high energy shock to restore the heart’s normal rhythm. 

No, the terms mean different things. Although ‘heart attack’ is often used to refer to a sudden cardiac arrest, this is incorrect. A heart attack (or myocardial infarction, to use the medical term) occurs when an artery supplying the heart with blood becomes blocked. This usually causes chest pain and leads to damage to some of the muscles of the heart. It may cause cardiac arrest, particularly in the early stages, but this is not inevitable.

The risk of cardiac arrest however, emphasises the importance of calling for immediate help if anyone is suspected of having a heart attack, so that they can receive treatment to reduce the damage to their heart and reduce the risk of a cardiac arrest occurring.

If bystanders who witness a cardiac arrest perform CPR, sufficient blood containing oxygen will reach the brain, heart, and other organs to keep the person alive for several minutes. CPR by itself will not restart the heart, but it ‘buys time’ for the emergency medical services to reach the scene. Effective CPR more than doubles the chance of someone surviving a cardiac arrest.

Compression-only CPR describes the performance of uninterrupted chest compressions without rescue breathing. In many adults who suffer a cardiac arrest, the heart stops abruptly; breathing will have been normal (or nearly normal), so the blood should be well-oxygenated.

In this situation, compression-only CPR may be effective for the first few minutes after the heart stops. This may provide time for the emergency services to arrive or an AED to be collected. Ultimately the oxygen will be used up and rescue breaths are required to give the individual the best chance of survival.

Where cardiac arrest is caused by lack of oxygen (as in drowning and most arrests that occur in children) compression-only CPR will be much less effective.

Chest compression alternating with rescue breaths is the ideal first aid procedure, but for untrained bystanders or those unwilling to give rescue breaths, compression-only CPR (hands only) is a useful and effective alternative.

When the heart stops, blood supply to the brain also stops. The individual will collapse unconscious and will be unresponsive.  

Breathing also stops, although it may take a few minutes to stop completely. For the first few minutes, the individual may take noisy, infrequent, or gasping breaths. 

The key features of cardiac arrest are therefore someone who is unconscious, unresponsive, and NOT BREATHING NORMALLY. Noisy, infrequent, or gasping breaths are NOT normal breathing. 

If you have any doubt call 999 immediately and start CPR. 

The Chain of Survival describes a sequence of steps that together maximise the chance of survival following cardiac arrest. 

Figure 1: Chain of Survival 

• The first link in the chain is the immediate recognition of cardiac arrest and calling for help 
• The second is the prompt initiation of CPR 
• The third is performing defibrillation as soon as possible 
• The fourth is optimal post-resuscitation care 

Like any chain, it is only as strong as its weakest link. If one stage is weak, the chances of successful resuscitation are compromised. 

In the UK fewer than 10% of all the people in whom a resuscitation attempt is made outside hospital survive. Improving this figure is a major priority for Resuscitation Council UK, the Department of Health and Social Care, ambulance services and first aid organisations. 

When all the stages in the Chain of Survival take place promptly, the figures are much better. This is possible where the arrest is recognised immediately, bystanders perform CPR, and an automated defibrillator is used before the ambulance service arrive. Survival rates in excess of 50% have been reported under these circumstances. 

It is very unlikely that someone in the UK who acted in good faith when trying to help another person would be held legally liable for an adverse outcome. No such action has ever been brought against someone who performed CPR and, in general, the courts in the UK look favourably on those who go to the assistance of others. 

Resuscitation Council UK has detailed guidance on the legal status of those who attempt resuscitation . This provides answers to most of the commonly asked questions on the subject. 

Training in CPR is provided by many organisations, and some classes also include instruction in the use of an AED. Many different kinds of training are provided, ranging from ‘hands-on’ classes with training manikins to purely internet-based distance-learning instruction. It is recommended that training should include practice on a training manikin. 

Many ambulance services also teach the general public: contact your local service for further details. 

The voluntary first aid organisations (for example St. John Ambulance, St. Andrew’s Ambulance, The British Red Cross and the Royal Life Saving Society) provide instruction; contact your nearest branch for details. There are also many private first aid training companies that provide training, and an internet search will identify those in your area. 

Resuscitation Council UK and British Heart Foundation have written a Guide to Automated External Defibrillators (AEDs) which gives detailed information about the use of AEDs in the community. We urge you to read this as it will answer your questions in more detail. 

Sudden cardiac arrest (SCA) occurs because the normal electrical rhythm that controls the heart is replaced by a chaotic disorganised electrical rhythm called ventricular fibrillation (VF). 

An AED delivers a high energy electric shock to an individual in SCA caused by VF to restore the heart’s normal rhythm. AEDs are compact, portable, easy to use and guide the operator through the process with prompts and commands. The AED analyses precisely the individual’s heart rhythm and will only deliver a shock if it is required.  

AEDs are very reliable and will not allow a shock to be given unless it is needed. They are extremely unlikely to do any harm to a person who has collapsed in suspected Sudden Cardiac Arrest. They are safe to use and present minimal risk to the rescuer, provided the instructions are followed. These features make them suitable for use by members of the public with little or no training. 

Public Access Defibrillation describes the use of AEDs by members of the public. AEDs can now be found in many busy public places including airports, mainline railway stations, shopping centres, and gyms. They are meant to be used by members of the public if they witness a cardiac arrest. 

RCUK has designed a sign that many public spaces equipped with a PAD will display. There are many different signs that mark the location of the AED. When you call the ambulance service you will be directed to the nearest registered device. Staff working at the location should also know the location of the nearest AED. 

Your nearest rescue-ready public access AED can be found on the national defibrillator network, The Circuit. 

When calling the emergency services, the call handler will also tell you where the nearest PAD will be.

AEDs have been used by untrained people to save lives. Clear, spoken instructions and visual illustrations guide users through the process. Lack of training should not be a barrier to someone using one. If a person is in cardiac arrest, do not be afraid to use an AED. 

Yes, it is usually safe to use an AED on an individual who is lying on a metallic, wet or other conductive surface. If the self-adhesive pads are applied correctly, and provided there’s no direct contact between the user and the individual when the shock is delivered, there is no direct pathway that electricity can take that would cause the user to experience a shock. If the individual is wet, their chest should be dried so that the self-adhesive AED pads will stick properly. 

Yes. Fortunately, cardiac arrest is rare in people who are pregnant, but if it were to occur it is quite appropriate to use an AED. The procedure is the same as in the non-pregnant person, but it is important to place the pads clear of enlarged breasts. 

Fortunately, sudden cardiac arrest (SCA) in school-age children is rare. Resuscitation attempts at schools are more likely to be made on an adult (staff member or visitor) than a pupil. The presence of an AED at a school therefore provides potential benefit for everyone present at the site. 

The Department for Education encourages schools in England to consider purchasing one or more defibrillators, and has published Automated External Defibrillators (AEDs: a guide for maintained schools and academies). It provides details on how to install, use and maintain a defibrillator in school, and how to buy a defibrillator.  

Resuscitation Council UK recommends that AEDs located in schools are accessible 24 hours a day, 7 days a week. The DfE programme will achieve even greater defibrillator coverage across England if they are placed on school gates and accessible to whole communities, rather than being locked inside schools. 

If you think an AED should be installed in your workplace, read the Guide to AEDs written by Resuscitation Council UK and the British Heart Foundation as this will answer your questions in detail. If you wish to proceed, contact your local ambulance service for further advice as described in the Guide.