Fast detection of renal ischemia in transplanted kidneys with delayed graft function-an experimental study.

Background: The newly transplanted kidney is difficult to monitor with regard to postoperative vascular thrombosis, especially when there is delayed graft function. We evaluated microdialysis as a tool for early ischemia detection in porcine kidneys with delayed graft function early after transplantation.

Methods: Sixteen pigs were transplanted with 26-hr cold ischemia kidneys. A microdialysis catheter was placed in the lateral renal cortex. Five hours after graft reperfusion, the pigs were randomized to renal arterial clamping or open artery, n=8 in each group, and further observed for 2 hr.

Results: The diuresis and glomerular filtration rate were low and decreasing throughout the study, with no significant differences between groups. Until arterial clamping, there were no significant differences in the development of local renal metabolites between the two groups. Renal artery clamping immediately caused significantly different development of all metabolites (P<0.02 for all) compared to the open artery group. After clamping, levels of glutamate and glycerol were significantly increased within 30 min (P=0.0049 and P=0.0061, respectively).

Conclusions: Microdialysis provided an early warning of arterial occlusion in transplanted grafts with delayed graft function. It may become a valuable tool for postoperative monitoring and detection of thrombosis after renal transplantation.