The Use of Hypothermia, Hyperbaria, and Metabolic Inhibition in Organ Preservation

Abstract

A most important aspect of organ transplantation is the prevention of ischemic damage. Suitable methods of preservation would make possible the widespread use of organs from cadaveric donors and would allow sufficient time for tissue typing, pretransplant preparation of the recipient and pretreatment of the isolated organ prior to transplantation.Any method for preservation in vitro of organs must protect against the altered physiology resulting from ischemia and hypoxia. Since the basic living unit is the cell, successful preservation must maintain cellular stability despite decreased oxygen supply, to which the cell is extremely sensitive. The maintenance of cellular integrity is a dynamic process resulting from a balance between breakdown and repair reactions.' Physiologic interruption of this balance by hypoxia or anoxia may cause irreversible damage unless protective compensation is afforded. The logical approach is to reduce metabolic activity. HYPOTHERMIA Hypothermia is the basis of our present methods to preserve the viability of organs. Its use is based on the fact that the oxygen requirements of individual mammals, organs and tissues drop exponentially with the decrease in temperature.2, 3 Organized investigation of the hypothermic state was not begun until this century. In 1905 Simpson and Herring4 showed in cats that when the body temperature was reduced below a certain level no anesthetic was necessary.Since that time, hypothermia has found widespread use in the fields of cardiac surgery and neurosurgery and transplantation and in the establishment of blood and tissue banks.We have designed several experiments to evaluate the use of hypothermia in kidney preservation. Initially, we sought to determine the advantage, if any, of antemortem treatment of the donor by total body hypothermia.5 The aim was to minimize renal ischemia by reducing metabolic activity.One group of dogs was made hypothermic (28° C) by external total body