[Differential cooling and perfusion: a reasonably safe method of systemic organ protection during surgery for acute type A aortic dissection].

During surgery for acute type A aortic dissection we have developed a new technique of cerebral and systemic organ protection according to susceptibility to ischemic damage. After cardiopulmonary bypass is established, patient is cooled to the rectal temperature of 30 degrees C. Then cardiopulmonary bypass is temporarily discontinued, the ascending aorta is opened, and myocardial protection is achieved by retrograde coronary sinus cold blood cardioplegia. To perform distal open repair, all 3 brachiocephalic arteries are cannulated with 13 F balloon catheters through the aortic lumen, and perfused with cold blood (12 degrees C) (10 ml/kg/min), while an additional larger balloon catheter (24 F) is inserted in the true lumen of the descending aorta, and systemic perfusion with warmer blood (28 degrees C) (1-2 l/min) is started. When the distal repair is completed, cardiopulmonary bypass is resumed and the systemic rewarming is started, meanwhile proximal repair is accomplished. Between December 1993 and August 1994, 10 patients were operated on with this method. Mean duration of cardiopulmonary bypass was 182 minutes (113 to 290), and mean duration of DCP was 63 minutes (18 to 130). Operative mortality was 10% (1/10). The technique of "differential cooling and perfusion" has been demonstrated to provide excellent cerebral and visceral protection and to minimize drawbacks associated with deep hypothermic methods necessitating prolonged cardiopulmonary bypass.