VOL: 98, ISSUE: 25, PAGE NO: 38
Mary Richardson, BSc, RGN, RNT, is manager of Heartstart UK, an initiative of the British Heart FoundationCoronary heart disease (CHD) is the largest single cause of death in the UK. Around 274,000 people in experience an acute myocardial infarction each year and about 30% die before reaching hospital (British Heart Foundation, 2002). Many die within the first few minutes of onset of symptoms. There is evidence that early access to emergency services, combined with early cardiopulmonary resuscitation (CPR) and defibrillation in the event of cardiac arrest, saves lives and improves quality of life post-survival. Equipping the public with the skills to act appropriately and with confidence in an emergency situation buys time and can mean the difference between life and death.
Coronary heart disease (CHD) is the largest single cause of death in the UK. Around 274,000 people in experience an acute myocardial infarction each year and about 30% die before reaching hospital (British Heart Foundation, 2002). Many die within the first few minutes of onset of symptoms. There is evidence that early access to emergency services, combined with early cardiopulmonary resuscitation (CPR) and defibrillation in the event of cardiac arrest, saves lives and improves quality of life post-survival. Equipping the public with the skills to act appropriately and with confidence in an emergency situation buys time and can mean the difference between life and death.
Early access in cardiac arrest
The most significant factor in the delay between onset of MI symptoms and receiving coronary care is a failure to call for help (Leslie et al, 1996). If cardiac arrest occurs, CPR needs to be started immediately and should coincide with efforts to gain access to the emergency services. Failure of the sufferer's circulation for just three to four minutes will cause irreversible cerebral damage (Resuscitation Council (UK), 1997).
Most cardiac arrests that happen in the first few hours after MI symptoms occur are due to ventricular fibrillation, and patients who are still in VF when the emergency services arrive are most likely to survive. In the absence of defibrillation the amplitude of VF progressively declines until terminal asystole occurs. CPR slows this process and thus increases the likelihood of the patient being in a shockable rhythm when a defibrillator becomes available.
About 70% of cardiac arrests occur outside hospital (Tunstall-Pedoe et al, 1996) and survival following a cardiac episode is optimal when:
- The arrest is witnessed;
- The rhythm is VF;
- The emergency services are summoned early;
- A bystander commences CPR;
- Defibrillation is performed as rapidly as possible;
- Advanced life support is instigated as rapidly as possible.
Even when cardiac arrest occurs, a witness may telephone others before calling the emergency services (Walters and Glucksman, 1989). Imprecise knowledge of how to activate the emergency system can cause confusion and delay.
Benefits of early CPR
In most cases of out-of-hospital cardiac arrest a bystander will be the first person on the scene and will need to start CPR. Many people who experience a cardiac arrest will not survive owing to a concurrent illness/underlying conditions. However, there is strong evidence to suggest that bystander CPR is a major factor in improving survival rates following a sudden cardiac arrest from VF. The highest survival rates from out-of-hospital cardiac arrest are found when the event occurs in the presence of an ambulance crew, and survival is poorest following non-witnessed arrests.
Early CPR has also been shown to improve neurological outcome. Cobbe et al (1996) report that 80% of survivors from out-of-hospital cardiac arrest were discharged with either minor or no neurological disability and only 2% had severe disability requiring institutional care. Although there is some uncertainty in the literature about how well CPR should be performed if it is to be effective, Handley et al (1997) advise that any CPR is better than none.
The need for resuscitation training
Experience in the UK and abroad suggests that training the public in emergency life support improves survival following out-of-hospital cardiac arrest. The International Liaison Committee on Resuscitation has stated: 'There is no question that CPR saves lives, yet after 30 years of attempts at public CPR education, most communities still do not train a sufficiently high proportion of the public to perform basic CPR' (Handley et al, 1997).
The British Heart Foundation has taken a lead in providing opportunities for the public to develop skills in emergency life support. The Heartstart UK initiative offers a coordinated approach to community resuscitation training. Engaging the commitment of all relevant organisations and engendering a sense of ownership of the project by communities is crucial to the success of the initiative. Local communities can be empowered through active involvement in local health issues.
Although training is aimed at the entire population, target groups have been identified to ensure maximum effect, including the families of people with a known history of heart disease.
Fitzpatrick et al (1992), who evaluated the potential impact of emergency intervention on sudden cardiac deaths in Glasgow, reported that of those dying as a consequence of cardiac arrest, about 50% had a previous diagnosis of coronary heart disease and, of that number, about half had previously experienced an MI.
Most out-of-hospital cardiac arrests take place in the home and the spouse or other relative is the most likely witness. There is a strong case for targeting resuscitation training at family members or carers of people with coronary heart disease.
Early CPR saves lives and more people, not simply the emergency services, should know how to administer it. A survey carried out for the Health Education Board for Scotland (1994) found that most members of the public felt they should be trained in CPR. The family members of cardiac patients also felt that hospital staff should make it their responsibility to inform them of the benefits of CPR training before the patient was discharged.
Opportunities should be provided for lay people to learn the vital skills of emergency life support. There is a high probability that the person they help will be a family member or someone they know.