Use of the new preservation solution Custodiol-N supplemented with dextran for hypothermic machine perfusion of the kidney.

Custodiol-N is a new preservation solution specifically designed to prevent free radical-induced tissue alterations and to protect vascular integrity of the graft. Thus, Custodiol-N appears particularly suitable as base solution for oxygenated machine preservation and its putative benefit for renal preservation by hypothermic machine perfusion (HMP) was investigated using a porcine in vitro model. Kidneys were retrieved from German Landrace pigs and preserved for 20 h by pulsatile oxygenated HMP on a Lifeport kidney transporter (syst. pressure 30 mmHg, 30cycles/min). Each graft was randomly assigned to the use of one of the following preservation solutions: Custodiol-N solution supplemented with 50 g/l dextran 40 (CND) or kidney perfusion solution 1 (KPS-1). Renal viability was evaluated upon reperfusion in vitro with diluted autologous blood from the donor for 120 min at 37°C. After 2h of postischemic reperfusion CND-preserved kidneys exhibited significantly higher renal blood flow and urine production. Oxygen consumption was also higher in the CND group than in KPS-1 kidneys. Clearance of creatinine increased during reperfusion of CND kidneys but declined in KPS-1 grafts ending in significantly higher values in CND kidneys. No differences between the groups were seen for enzyme release or fractional excretion of sodium. In conclusion the data presented provide first experimental evidence for adequate organ protective potential of CND in HMP as compared to the gold standard KPS-KPS-11.