Hands-on defibrillation: theoretical and practical aspects of patient and rescuer safety.

Defibrillators are used to treat many thousands of people each year using very high voltages, but, despite this, reported injuries to rescuers are rare. Although even a small number of reported injuries is not ideal, the safety record of the defibrillator using the current protocol is widely regarded as being acceptable. There is increasing evidence that clinical outcome is significantly improved with continuous chest compressions, but defibrillation is a common cause of interruptions; even short interruptions, such as those associated with defibrillation, may detrimentally affect the outcome. This has led to discussions regarding the possibility of continuing chest compressions during defibrillation; a process involving a rescuer working in close proximity to voltages of up to 5000 V. Not only do voltages of this magnitude have significant implications for the rescuer performing chest compressions, but there are also risks to other rescuers in the proximity, the patient and other bystanders. Clearly any deviation from accepted practice should only be undertaken following careful consideration of the risks and benefits to the patient, rescuers and others. This review summarises the physical principles of electrical risk and identifies ways in which these could be managed. In doing so, it is hoped that in future it may be possible to deliver continuous and safe manual chest compressions during defibrillator discharge in order to improve patient outcome.