Experience with an automatic external defibrillator

Automatic external defibrillators: lessons from the past, present and future

Coronary artery disease remains the leading cause of death in the United States and most developed countries. Many of the victims die from sudden cardiac arrests, resulting from dysrhythmias-most commonly ventricular fibrillation. Since most cardiac arrests occur outside the hospital, implementing emergency services in the field will have a great impact on survival. With the development of the modern automatic external defibrillator (AED), early recognition and correction of these dysrhythmias by lay rescuers can significantly improve outcome from sudden death. This paper reviews the past, present and future development and applications of AEDs.

Clinical experience with three different defibrillators for resuscitation of out of hospital cardiac arrest

Three defibrillators, one manual and two different semiautomatic, were prospectively compared during a one year period for out-of-hospital use by ordinary ambulance personnel with short additional training. Eighty-three cardiac arrest patients were treated with one of two different semiautomatic defibrillators and 26 by an ordinary manual defibrillator. Twenty-nine were found in ventricular fibrillation. Five of these patients were successfully resuscitated and admitted for further hospital care, two survived to be discharged home. The semiautomatic defibrillators were found to be accurate in ECG interpretation, sensitivity and specificity was 100%, respectively, and both were equally effective in defibrillation. There were no differences in conversion rate or in the clinical outcome between the three defibrillators tested. Both semiautomatic defibrillators tested seemed to be safe, reliable and cost-effective. The low survival rate found is most certainly due to a long ambulance delay.

One year's experience of early defibrillation in Stockholm

The effects of resuscitation on patients who died suddenly out of hospital were evaluated after the introduction of early defibrillation performed by ambulance personnel using semi-automatic defibrillators. Resuscitation attempts were initiated in 548 patients during the 1-year study period. Mean ambulance delay was 7.5 min, 22% of the cardiac arrest patients had received bystander cardiopulmonary resuscitation (CPR). Sensitivity and specificity for the semi-automatic defibrillator in the interpretation of ventricular fibrillation was found to be 97 and 100% respectively. Only 28 (14%) of the 206 defibrillated patients regained circulation and were admitted for further hospital care. Only three survived to be discharged. Among the 342 patients in whom defibrillation was not indicated, 16 (5%) regained circulation and were admitted for further hospital care and one (0.3%) survived to be discharged. Semi-automatic defibrillators seem reliable, safe and inexpensive; however, the isolated addition of defibrillation to basal ambulance service seems to be inadequate in Stockholm. We need to evaluate what further resources are of importance to guarantee a successful outcome.