Continuous retrograde hypothermic low flow cerebral perfusion (CRCP) with deep hypothermic systemic circulatory arrest (DHSCA) during aortic arch surgery was employed in six patients, aged 21-79 years. From August 1991 to November 1992, five of these patients were operated for ascending and arch aortic dissection type I, and one patient was operated for an aneurysm extending from the ascending aorta into the arch. Cardiopulmonary bypass (CPB) technology included a centrifugal pump and low-dose aprotinin. Venous drainage was established via the superior and inferior caval veins and arterial return via the femoral artery. Prior to CPB, a bypass line connecting the arterial line with the superior vena cava cannula was implemented. Prior to DHSCA, the patients were systemically cooled to a mean nasopharyngeal temperature of 15.2°C. After induction of systemic circulatory arrest, the femoral artery cannula was clamped. Thereafter, the implemented bypass line was opened to achieve reverse flow into the superior vena cava to allow venoarterial perfusion. The perfusate was returned to the CPB circuit through drainage from the inferior caval vein and by aspiration of blood from the opened aortic arch. CRCP flow rate ranged from 250 to 450 ml/min (mean 375 ml/min) maintaining an internal jugular vein pressure between 18 and 25 mmHg. The duration of CRCP ranged from 24 to 55 minutes (mean 39 minutes). Postoperatively, one patient died of cardiac failure. The other five patients regained full consciousness without neurological deficits, as defined by the Glasgow coma score, within 48 hours after the operation. Neither did we see other major organ complications. At present four patients are alive nine to 24 months after surgery and they are in New York Heart Association (NYHA) functional classification I-II. Our experience indicates that CRCP is safe and effective, avoiding cerebral circulatory arrest. Furthermore, this technique avoids clamping of cerebral vessels, reduces the chances of embolism of particulate debris and of cerebral air intrusion into opened cerebral vessels.
Surgery of the thoracic aorta with hypothermic circulatory arrest: experience with retrograde perfusion via the superior vena cava and demonstration of cerebral perfusion
