Hypothermia and circulatory arrest for surgical resection of aortic arch aneurysms.

In the 6 year period 1976 through 1981, 13 patients had surgical correction of aneurysms of the aortic arch with the use of deep systemic hypothermia (15 degrees to 24 degrees C) and partial (lower body only) or complete circulatory arrest. Three pathological groups were recognized: Group I (seven patients), with involvement of the aortic arch only; Group II (two patients), with extension of disease from the arch into its major vessels; and Group III (four patients), with predominant involvement of the major vessels. In the first eight patients (1976 to 1979), the carotid arteries were perfused directly with circulatory arrest of the rest of the body. Three of the eight patients (37.5%) died, two of cerebral complications and one of respiratory failure. Another patient had a nonfatal neurologic complication. In the last five patients (1980 to 1981), the carotid arteries were not perfused and variable periods of cerebral ischemia under hypothermic protection (18 degrees C) were permitted. All patients survived, and only one showed transient, minor neurologic changes. Our current recommended technique includes deep systemic hypothermia (15 degrees to 18 degrees C) using femoro-femoral bypass, complete circulatory arrest, and temporary occlusion of the carotid arteries. Additional protection of the myocardium is achieved by cold potassium (20 mEq/L) cardioplegia. Repair of the aneurysm is performed from within the aortic arch in a bloodless field. The hitherto high mortality and morbidity following resection of aneurysms of the aortic arch can be greatly reduced using this simplified technique.