THORACOTOMY and open-chest cardiac massage have been used for some time in the management of sudden circulatory arrest. Although useful, the procedure is a formidable undertaking, particularly when not done in the operating room.Recently, Kouwenhoven, Jude and Knickerbocker∥ described a technic for cardiac massage without opening the chest. Their report, and the early gratifying experience with this technic at the Massachusetts General Hospital, prompted a review of the 84 cases in which it has been used here by many members of the staff during the past six months. Every case has been included in which external cardiac massage was . . .