The three-phase model of cardiac arrest as applied to ventricular fibrillation in a large, urban emergency medical services system
ABSTRACT Cardiac arrest is responsible for significant morbidity and mortality, with consistently poor outcomes despite the rapid availability of prehospital personnel for defibrillation attempts in patients with ventricular fibrillation (VF). Recent evidence suggests a period of cardiopulmonary resuscitation (CPR) prior to defibrillation attempts may improve outcomes in patients with moderate time since collapse (4-10 min).
To determine cardiac arrest outcomes in our community and explore the relationship between time since collapse, performance of bystander CPR, and survival.
Non-traumatic cardiac arrest data were collected prospectively over an 18-month period. Patients were excluded for: age <18 years, a "Do Not Attempt Resuscitation" (DNAR) directive, determination of a non-cardiac etiology for arrest, and an initially recorded rhythm other than VF. Patients were stratified by time since collapse (<4, 4-10, > 10 min, and unknown) and compared with regard to survival and neurological outcome. In addition, patients with and without bystander CPR were compared with regard to survival.
: A total of 1141 adult non-traumatic cardiac arrest victims were identified over the 18-month study period. This included 272 patients with VF as the initially recorded rhythm. Of these, 185 had a suspected cardiac etiology for the arrest; survival to hospital discharge was 15% in this group, with 82% of these having a good outcome or only moderate disability. Survival was highest among patients with time since collapse of less than 4 min and decreased with increasing time since collapse. There were no survivors among patients with time since collapse greater than 10 min. Among patients with time since collapse of 4 min or longer, survival was significantly higher with the performance of bystander CPR; there was no survival advantage to bystander CPR among patients with time since collapse less than 4 min.
The performance of bystander CPR prior to defibrillation by EMS personnel is associated with improved survival among patients with time since collapse longer than 4 min but not less than 4 min. These data are consistent with the three-phase model of cardiac arrest.
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ABSTRACT: Cardiopulmonary resuscitation (CPR) training is gaining more importance for medical students. There were many attempts to improve the basic life support (BLS) skills in medical students, some being rather successful, some less. We developed a new problem based learning curriculum, where students had to teach CPR to cardiac arrest survivors in order to improve the knowledge about life support skills of trainers and trainees. Medical students who enrolled in our curriculum had to pass a 2 semester problem based learning session about the principles of cardiac arrest, CPR, BLS and defibrillation (CPR-D). Then the students taught cardiac arrest survivors who were randomly chosen out of a cardiac arrest database of our emergency department. Both, the student and the Sudden Cardiac Death (SCD) survivor were asked about their skills and knowledge via questionnaires immediately after the course. The questionnaires were then used to evaluate if this new teaching strategy is useful for learning CPR via a problem-based-learning course. The survey was grouped into three categories, namely "Use of AED", "CPR-D" and "Training". In addition, there was space for free answers where the participants could state their opinion in their own words, which provided some useful hints for upcoming programs. This new learning-by-teaching strategy was highly accepted by all participants, the students and the SCD survivors. Most SCD survivors would use their skills in case one of their relatives goes into cardiac arrest (96%). Furthermore, 86% of the trainees were able to deal with failures and/or disturbances by themselves. On the trainer's side, 96% of the students felt to be well prepared for the course and were considered to be competent by 96% of their trainees. We could prove that learning by teaching CPR is possible and is highly accepted by the students. By offering a compelling appreciation of what CPR can achieve in using survivors from SCD as trainees made them go deeper into the subject of resuscitation, what also might result in a longer lasting benefit than regular lecture courses in CPR.BMC Medical Education 02/2006; 6:27. DOI:10.1186/1472-6920-6-27 · 1.41 Impact Factor
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ABSTRACT: Sudden cardiac death is a major cause of mortality in the United States of America (Circulation 2008;117:e25-146) with approximately 310000 deaths related to coronary heart disease occurring in emergency departments or in the prehospital environment annually. Several organizations have directed resources toward the treatment of sudden cardiac arrest through a paradigm that has come to be known as the "chain of survival"-prompt activation of emergency response by telephone 911, early bystander cardiopulmonary resuscitation, early defibrillation, and timely advanced cardiac life support (Circulation 1991;83:1832-1847). The ready availability of automated external defibrillators (AEDs) has been advocated as a key component of this chain. Some authors have suggested a "fire extinguisher model" for AED deployment (Circulation 1998;98:2334-2351; Resuscitation 1995;30:151-156; Ann Intern Med 2001;135:990-998). In this model, AEDs are prominently displayed in public places for use by laypersons, much like fire extinguishers. For example, in Chicago's O'Hare Airport, AEDs are placed alongside fire extinguishers in the public concourse (N Engl J Med 2002;347:1242-1247). Advocates of this model suggest that advancing this practice would be a means to widely disbourse life-saving technology that is easy to use. Several experts have questioned this model, suggesting that the cost-effectiveness of distributing AEDs this widely would be prohibitive (BMJ 2002;325:515; Curr Opin Cardiol 2007;22:5-10; BMJ 2003;326:162; Int J Technol Assess Health Care 2007;23:362-367) and may not be more effective than more targeted distribution of AEDs. This literature review will examine the available data on both AEDs and fire extinguishers to determine if these comparisons are reasonable as a means of guiding public policy.Progress in cardiovascular diseases 11/2008; 51(3):204-12. DOI:10.1016/j.pcad.2008.05.003 · 4.25 Impact Factor
Article: Advances in resuscitation.Circulation 08/2012; 126(8):991-1002. DOI:10.1161/CIRCULATIONAHA.111.023895 · 14.95 Impact Factor