Renal allograft preservation: A comparison of University of Wisconsin solution and of hypothermic continuous pulsatile perfusion

Abstract

A study was performed to compare early allograft function in kidneys preserved with University of Wisconsin (UW) solution to kidneys preserved by hypothermic pulsatile perfusion. The study consisted of two sets of data. The first set was a donor‐paired study (matched data) of 30 heart‐beating, hemodynamically stable donors. After removal from the donor each cooled kidney was individually prepared for preservation. One kidney was flushed with ± 500 ml of UW solution and stored in UW solution on slushed ice. The other kidney was continuously perfused with cooled (4–6°C) cryoprecipitated plasma. The kidneys were transplanted into suitable recipients in a random sequence. Twelve donors were excluded from the study because one or both kidneys were transplanted into recipients who had previously been transplanted. The remaining 36 kidneys were implanted into two similar groups after a mean of 19 hours in the pulsatile perfusion group and 18 hours in the UW solution group. The second set of data consisted of all the kidneys preserved in UW solution (n=62) at our institution and of 57 kidneys preserved by hypothermic continuous pulsatile perfusion during the same period (mixed data) and was used to evaluate the effect of prolonged preservation (longer than 24 hours) on delayed graft function. Both of these groups were also comparable. Acute tubular necrosis (ATN) was defined as the need for dialysis during the 1st week after transplantation, and delayed function as the delayed clearance of creatinine during the early postoperative phase. In the donor‐matched data study the incidence of ATN (UW solution 28%; pulsatile perfusion 33%), delayed function (UW solution 44%; pulsatile perfusion 44%), and the 1‐year graft survival (UW solution 83%; pulsatile perfusion 82%) were similar. In addition, ATN occurred in all kidneys (n = 2) stored for longer than 24 hours in the UW solution group compared to 2 of 5 kidneys in the pulsatile perfusion group. In the mixed data study, ATN occurred in 12 of 15 kidneys (80%) preserved in UW solution for 24 hours or longer, compared to 6 of 13 kidneys (46%) in the hypothermic continuous pulsatile perfusion group (Fisher's exact test; p = 0.07). This study demonstrates that there is no difference in the incidence of ATN, delayed function, and in the 1‐year graft survival in kidneys preserved in UW solution when compared to kidneys preserved by hypothermic continuous pulsatile perfusion. The incidence of ATN does, however, appear to increase dramatically if kidneys are preserved in UW solution for longer than 24 hours. Such problems do not occur in kidneys preserved with hypothermic continuous pulsatile perfusion.