Deliberate circulatory arrest; the use of halothane and heparin for direct-vision intracardiac surgery.

new procedure being described which involves deliberately preventing blood from passing through the chambers and valves of the heart. In some of these operations, when considerable time is required for their completion, a partial solution has been found in the employment of by-pass techniques. These methods demand extensive vascular surgery to connect the apparatus to the patient, and large volumes of blood must be added to the circulation because of the extracorporeal pumping and oxygenation. As the result, the hazards of by-pass techniques are not negligible. Various attempts have been made to perform the shorter intracardiac operations without the use of an extracorporeal circulation. In general, the principle used has been to arrest the inflow of blood to the heart during the time necessary to complete the operation. This has involved the arrest of the cerebral circulation, and the limiting factor has been the survival time of the cerebral tissues in the absence of circulation.