Renal autotransplantation and ex vivo renal surgery: surgical treatment of renovascular hypertension.

Autotransplantation of the kidney has proved to be an extremely valuable surgical alternative for the treatment of renovascular hypertension. The modern operation is founded in landmark surgical experiments performed during the early years of this century. Despite the relative technical simplicity and considerable potential application of renal autotransplantation, the operation was not employed for at least a decade following the more uncertain initial clinical adventures in renal allotransplantation. Since its inception, however, the successful use of renal autotransplantation for renovascular hypertension has been well documented in a relatively small but impressive series of clinical situations. Renal autotransplantation in the surgical management of renovascular hypertension appears to afford many technical advantages vis-à-vis in situ renal revascularization including the option to perform meticulous ex vivo reconstructive surgery. The need to interrupt the renal circulation during renal autotransplantation and the possibility that the ischemic operative interval might result in renal cellular damage, has been a deterrent to greater consideration of this surgical alternative. Cold perfusion of the ischemic kidney has been regarded as "inherently" necessary in order to prevent intravascular coagulation and to protect the kidney through the use of hypothermia until the circulation is re-established. A wide variety of perfusates and methods of perfusion have been successfully employed for these purposes. A new perfusate has been formulated which is intended to help prevent the rapid and profound changes in the amounts of distribution of intracellular electrolytes and water which are known to occur when the kidney is deprived of its circulation. This solution appears to be effective in preventing significant damage in ischemic canine kidneys during at least three hours of normothermic exposure, and at least five hours of ambiothermic exposure following a single initial cold perfusion. The various perfusates and methods of renal perfusion for clinical and experimental renal autotransplantation and ex vivo renal surgery are herein compared and contrasted with regard to their proposed mechanisms of action, apparent effectiveness, and simplicity of application.