Cold ischemia and outcome in 17,937 cadaveric kidney transplants

To determine if cold preservation time continues to affect renal transplant outcome, prospectively collected data from 17,937 cadaveric renal transplants performed between 1982 and 1991 were analyzed. Cold preservation intervals of 1-16, 16-32, 32-48, and greater than 48 hr were studied by multi- and univariate methods for two time periods: 1982-1989 (n = 13,800) and 1990-1991 (n = 4137). The functional one-year graft survival for kidneys stored over different intervals was significantly different (P < 0.001) only for the 1982-1989 epoch: one-year allograft survival ranged from 76% (1-16), to 72% (16-32 and 32-48) to 74% (> 48) hr. One-year graft survival ranged from 81 to 83% for the four preservation times in 1990 through 1991 (P = NS). Overall actuarial graft survival was 76% (74% prior to 1990, and 82% after 1990). Factors significantly (P < 0.0001) affecting kidney transplant outcome before and after 1990 were delayed graft function (DGF): n = 4232, 65% one-year graft survival; retransplant status: n = 3029, 67% one-year graft survival; and HLA match at three or more loci: n = 6067, 79% one-year graft survival. While DGF occurred more often with prolonged preservation, kidneys with DGF had similar survival regardless of preservation duration. Before 1990, pretransplant transfusion was associated with better and black recipient race with worse outcome; neither transfusion nor recipient race had any effect after 1990. Patients receiving kidneys preserved for longer periods demonstrate one-year graft survival comparable to kidneys preserved for shorter periods. Prolonged cold ischemic time should no longer be a principal reason for considering organ discard.