This article explores the collaboration of doctors and nurses in establishing the Cardiac Arrest Paradigm (Paradigm), an intellectual and institutional framework that has shaped the practice of medicine for the past fifty years. An important manifestation of the Paradigm was the intensification of care, particularly at the end of life, whether or not it would help the patient. Paradigm also tended to narrow the physician's clinical gaze to single-organ systems, with the application of therapies based on narrow indications, often without regard to the whole patient. Cardiac arrest/resuscitation represents the quintessential indication/therapy dyad of the Paradigm and was formative in its creation. I argue that the interprofessional interactions between doctors and nurses constitute one of several factors that promoted the Paradigm within mid-twentieth-century medicine.Many of the underlying principles of the therapy for cardiac arrest were already established by the mid-twentieth century, when resuscitation still involved cutting open the body and squeezing the heart-open cardiac massage-and started moving out of the operating room onto the wards of the hospital in the 1950s. But the Paradigm clicked into existence after closed chest compressions and cardiopulmonary resuscitation (CPR) became the norm in the 1960s. At this time, a constellation of forces made resuscitation the default therapy for every patient whose heart stopped in the hospital, regardless of its expected efficacy, and cardiac arrest became the clinical condition we recognize today. This development marked a pivotal transformation in the history of medicine, not so much for the new technology-resuscitation had been practiced in various overlapping ways since the late eighteenth century-but because CPR and its indication, cardiac arrest, helped establish a model of care, a Paradigm that has gone largely unchallenged to the present day.A 1962 Circulation editorial on CPR is revealing. Most people who experience sudden stoppage or disruption of the heart beat (cardiac arrest) cannot be saved even under ideal circumstances in a hospital.1 authors specify the limited efficacy of CPR and infer in the next line that CPR had not yet become the default therapy for everyone whose heart stopped. The least measure of success has been experienced in coronary 'attack' cases. That this group experienced the least success implies that the comparison group was most likely patients whose heart stopped in the operating room, where cardiac resuscitation was initially developed and almost exclusively practiced until the 1950s. If everyone whose heart stopped in the hospital had been included in the resuscitation efforts, then those with cardiac arrest from other problems, including terminal conditions surely would have had the least measure of success. Although some patients from this group may have undergone resuscitation in 1962, it appears that they did not all receive resuscitation; CPR was not yet the default.One way of getting to the core of the Paradigm is to ask how a procedure that would not benefit most patients became the default treatment for everyone whose heart stopped in the hospital. accepted explanation for this phenomenon is the need for fire drill-like orchestration for the cardiac arrest team.2 Although precise and routinized execution of the therapy is doubtless a factor in the development of the Paradigm, there were many other forces that also drove it forward (see Table 1). One of the important forces in the early days of CPR was the interprofessional collaboration between nurses and physicians.Curiously, the 1962 Circulation editorial provided no additional guidance concerning who should and who should not receive CPR. Instead, the limitation is placed on who should perform it, with the last line stating, The undersigned organizations joining in the statement believe that emphasis should be placed at this time on training physicians, dentists, nurses, and specially qualified emergency personnel, so that the procedure will become more widely available. …