Background: This study evaluated the usefulness of machine perfusion preservation parameters as indicators of kidney graft viability.
Methods: Eighty-eight cadaveric kidneys were analyzed in this study. Of these, 74 kidneys (84.1%) were procured from nonheartbeating donors. The criteria for an acceptable kidney for transplantation were a perfusion flow of more than 0.4 mL/min/g with a concurrent decreasing perfusion pressure. The average perfusion pressure was 30-50 mmHg. We divided the kidneys into three groups: group 1 (n=35), 0.45-0.65 mL/min/g machine perfusion flow (MPF); group 2 (n=30), 0.65-0.90 mL/min/g MPF; and group 3 (n=23), more than 0.9 mL/min/g MPF.
Results: A higher rate of primary nonfunction (PNF; 25.7%) was found in group 1, compared with 6.7% in group 2 and 0% in group 3. A higher rate of 30.4% immediate function was found in group 3, compared with 16.7% in group and 8.6% in group 1. However, a longer period of acute tubular necrosis (ATN; 12.0 days) was found in group 1 compared with 8.6 days in group 2 and 8.7 days in group 3. PNF was detected in 7 (77.8%) cases with more than 16 hr of total ischemic time (TIT) in group 1. In contrast, all of nine cases with more than 16 hr of TIT in group 3 were functional.
Conclusions: MPF is a reliable indicator of graft viability based on the rate of PNF and immediate renal allograft function, especially in marginal donors.