No abstract

In split-liver transplantation, the entire portal flow is redirected through relatively smallfor-size grafts. It has been postulated that excessive portal blood flow leads to graft injury. In order to elucidate the mechanisms of this injury, we studied the hemodynamic interactions between portal veinand hepatic artery flow in an experimental model in pigs. Six whole pig liver grafts were implanted in Group 1 (n = 6) and six whole liver grafts were split into right and left grafts and transplanted to Groups 2 (n = 6) and 3 (n = 6), respectively. The graftto-recipient liver volume ratio was 1:1, 2:3 and 1:3 in Groups 1, 2 and 3 , respectively. Portal vein-and hepatic artery flows were measured with an ultrasonic flow meter at 60,120 and 180min after graft reperfusion. Portal vein pressure was also recorded at the same time intervals. Graft function was assessed at 3,6h and 12h, and morphological changes at 12h after reperfusion. Following reperfusion, portal vein flow showed an inverse relationship to graft size, while hepatic artery flow was reduced proportionately to graft size. The difference was significant among the three groups (P

Segmental liver grafts with a calculated ideal liver weight (CILW) less than 40% may be associated with portal flow-related injuries and primary dysfunction. This study evaluated the effect of mesocaval shunts on the survival of grafts with a CILW less than 20%. Sixteen pigs underwent orthotopic transplantation of segmental liver grafts with a CILW less than 20%. In eight animals (study group), transplantation was combined with a mesocaval shunt, and eight animals served as controls without a mesocaval shunt. Liver function, systemic hemodynamics, portal vein pressure, intracranial pressure, and cerebral perfusion pressure were assessed postoperatively. The controls showed a rapid impairment of liver function reflected by a significant elevation in aspartate aminotransferase, international normalized ratio, bilirubin, and intracranial pressure and a decrease in cerebral perfusion pressure compared with the study group (P<0.05). Mesocaval shunts showed protective effects on grafts with CILW less than 20% and may have a clinical role in the salvage of small-for-size liver grafts.