Oxygenated kidney preservation techniques.

Improving preservation techniques to minimize injury is of particular importance in organs from marginal donors. Since the introduction of transplantation and routine use of hypothermic temperatures for kidney preservation, there has been much debate on whether it is necessary to add oxygen to support the low level of metabolism under these conditions. Supplementing the kidney with oxygen during hypothermic preservation is not common practice. However, there is evidence to support its application. Oxygen can be added by various techniques such as retrograde persufflation whereby filtered and humidified oxygen is bubbled through the vasculature; under hyperbaric conditions using specialized pressurized chambers; during hypothermic machine perfusion; with the addition of oxygen carriers; and under normothermic conditions. Evidence suggests that oxygenation is particularly beneficial in restoring cellular levels of adenosine triphosphate after kidneys have been subjected to warm or cold ischemic injury. However, under normal conditions, the benefits are less convincing, but the evidence is insufficient to draw any conclusions. This overview explores the ways in which oxygen can be administered during preservation in experimental and clinical models of kidney transplantation.