Abstract
One hundred and sixty thousand people in England and Wales die from coronary heart disease each year. Thirty three percent of males, and 15% of females are under the age of 65, and 25% of these patients die before reaching hospital (Rose 1981). These observations illustrate the need for improving methods of dealing with pre-hospital cardiac arrest. In the United Kingdom, progress in developing methods of coping with cardiac arrest in the community has been slow compared with the United States. Few controlled studies have been performed, and no previous research has been carried out in London. This thesis concerns different strategies for dealing with pre-hospital cardiac arrest in London, it is presented in several parts. Part One is a retrospective study, describing a pilot scheme initiated by the London Ambulance Service, involving a small group of ambulance staff who had been trained in all advanced cardiac life support skills. Sixty two victims with cardiac cause of arrest were treated, 4/62 (6%) survived to leave hospital. It was concluded that the time between collapse of the victim in cardiac arrest and definitive care was too long for survival in most of the patients studied. The ambulance staff trained were found to be proficient in ECG rhythm recognition and drug administration, but errors in their application of skills further increased the time to definitive care. In Part Two, the use of automated external defibrillators by minimally trained ambulance staff is investigated. Of 186 cardiac arrest victims treated, six (3%) survived to be discharged from hospital. The automated defibrillator used was found to be accurate in ECG rhythm recognition. The ambulance staff were able to operate the device effectively following training, but again, avoidable delays in treatment of patients secondary to the actions of the ambulance crew were identified. Neither of the strategies described in Parts One and Two (advanced cardiac life support, or automated defibrillation only) appeared superior in terms of patient outcome. However, inadequate numbers of survivors proved to be a limitation of both studies, and prevented meaningful comparisons. It was concluded that different strategies for dealing with pre-hospital cardiac arrest in London should be employed, in addition to definitive care provision by the regular ambulance service. Part Three explores this possibility, by investigating acquisition and retention of the skills of automated defibrillation in St John Ambulance volunteers. Results showed that both trained nurse and lay St John volunteers were equally able to acquire and retain the essential skills of automated defibrillator use following a brief training programme. In future, the most benefit will ‘be achieved by investigating ways of reducing the time interval between collapse of the victim in cardiac arrest and provision of definitive care in London.