The influence of pulsatile preservation on renal transplantation in the 1990s

Background. Unlike simple cold storage (CS), pulsatile machine preservation (MP) of kidneys for transplantation permits pharmacologic manipulation of the perfusate and aids in the pretransplant assessment of the kidney graft. These characteristics of MP may have importance in the era of increasing u se of extended criteria donor kidneys. The overall aim of this article is t o critically assess practices at our preservation unit with respect to graf t function. Specific aims are to (1) compare the influence of MP versus CS on graft function, (2) determine which pretransplant variables have signifi cance in pretransplant assessment, and (3) determine whether pharmacologic manipulation during MP is advantageous, Methods. There were 650 consecutive kidneys preserved in our laboratory bet ween January 1, 1993 and March 1, 999, by either MP or CS. All MP kidneys w ere preserved by continuous hypothermic pulsatile perfusion using Belzer-MP S or Belzer II solution. Perfusion parameters and electrolytes were measure d serially during pulsatile perfusion. All CS kidneys were stored in Univer sity of Wisconsin solution, All kidneys obtained from donors exhibiting ext ended criteria features underwent pretransplant frozen section biopsies. Tr ansmission electron microscopy (EM) was performed on a subset of kidneys un dergoing pharmacologic manipulation. Four agents were assessed prospectivel y for their ability to influence MP characteristics when added to perfusate : PGE,, trifluoperazine, verapamil, and papaverine. Results. MP was associated with improved immediate, 1-, and 2-year graft fu nction and reduced length of initial hospital stay when compared with CS gr afts. Changes in the machine perfusion variables flow and resistance, and t he [Ca++] in perfusate, were significantly associated with delayed graft fu nction (DGF) after the transplant. Biopsy information was not predictive of DGF, The addition of PGE, to perfusate improved MP characteristics, reduce d the release of [Ca++] into perfusate, and ameliorated mitochondrial ische mic injury in transmission EM images, Early graft function was improved in the presence of PGE(1)+MP, compared with function in the presence of other pharmacologic agents or CS alone. Conclusions. MP is associated with improved early and long term renal funct ion. Moreover, PGE, augments MP in improving graft function. The combinatio n of MP+PGE(1) may be important in optimizing the ability to use extended d onor criteria kidneys and, thereby, improve the overall efficiency of cadav eric renal transplantation.