Background. It is proposed that retrograde abdominal perfusion be used in combination with retrograde cerebral perfusion to provide total body visceral protection during aortic reconstruction; however, its physiologic effects remain unknown. Methods. We compared the effect of superior vena caval perfusion alone with that of combined superior and inferior vena caval perfusion on the liver and kidney in 6 mongrel dogs. Organ blood now was measured using ultrasonic flow probes on the hepatic artery, the portal vein, and the renal artery. Regional tissue blood now to the liver and the kidney was assessed using colored microspheres and pH probes. Anesthetized dogs were placed on total cardiopulmonary bypass. After cooling to 20 degrees C, retrograde perfusion was begun with 30 minutes of superior vena caval perfusion followed by another 30 minutes of bicaval perfusion, or vice versa. Results. Very little renal blood now was measured with either method of retrograde perfusion. Although the liver received more blood flow in comparison to the kidney, there was no significant difference between superior vena caval perfusion alone and bicaval perfusion. The addition of inferior vena caval perfusion results in portal hypertension, hepatic congestion, ascites, and bowel edema. Conclusions. In the canine model, bicaval perfusion does not provide superior protection to the liver and kidneys when compared with superior vena caval perfusion alone.