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Prehospital cardiopulmonary resuscitation. Is it effective?

TWO PARADOXES lie behind the question posed in the title of this article. First, rapid and widespread dissemination of the technique of cardiopulmonary resuscitation (CPR) occured before the underlying physiology was fully understood. Second, data that indicate discouragingly low coronary and carotid artery flow rates contrast sharply with the obvious lifesaving capacity of basic CPR. CPR In the early 1960s, Kouwenhoven et al1demonstrated the effectiveness of closed-chest compressions for cardiac arrest; rapid worldwide dissemination of the technique soon followed. By 1974, the endorsement of influential groups such as the American Heart Association secured broad acceptance for standard CPR.2Kouwenhoven and co-workers thought that during CPR blood was expelled by compression of the heart between the sternum and vertebral bodies. Later, however, various research laboratories conducted what were, in effect, post hoc investigations into the physiology of CPR; by the 1980s, few researchers subscribed to Kouwenhoven and co-workers'