Multicenter analysis of kidney preservation

Background. Kidney preservation is an integral part of clinical kidney transplantation. Changes in the use of preservation methods and storage solutions, ischemic preservation times, and the relationship between ischemia time and human leukocyte antigen (HLA) match have not been extensively studied in recent years. Methods. The Collaborative Transplant Study database was used to analyze effects of kidney preservation methods and times. Graft survival and death-censored functional survival were used as endpoints. In all, 91,674 transplants from deceased donors were analyzed using univariate and multivariate methods. Results. Cold storage accounted for more than 95% of kidney preservations from 1990-2005. Increasing ischemia up to 18 hr was not detrimental for graft outcome, whereas the risk of graft failure rose with ischemia 19-24 hr to relative risk (RR) 1.09, 25-36 hr to RR 1.16, and > 36 hr to RR 1.30 (P < 0.001). As compared to other preservation solutions, University of Wisconsin (LTW) solution was associated with significantly better outcome when ischemia exceeded 24 hr. Short ischemia did not eliminate the effect of HLA matching. Kidneys from young or old donors were affected by prolonged ischemia to similar degrees. Pulsatile machine perfusion was not superior to cold storage. Conclusion. Kidneys from deceased donors should ideally be transplanted within 18 hr. Within the 18-hr window, the time of ischemia has no significant influence on graft survival. UW solution should be used if preservation for longer periods is envisioned. HLA matching improves graft survival regardless of length of ischemia.