Transplantation Immunology

Hicks, Mark, Hing, Alfred, Gao, Ling, Ryan, Jonathon, MacDonald, Peter S., Mark Hicks, Alfred Hing, Ling Gao, Jonathon Ryan, Peter S. MacDonald

The success of organ transplantation is critically dependent on the quality of the donor organ. Donor organ quality, in turn, is determined by a variety of factors including donor age and preexisting disease, the mechanism of brain death, donor management prior to organ procurement, the duration of hypothermic storage, and the circumstances of reperfusion. It has been recognized for some time that both the short- and long-term outcomes after cadaveric organ transplantation are significantly inferior to those obtained when the transplanted organ is obtained from a living donor, regardless of whether the donor is related or unrelated to the recipient. Brain death results in a series of hemodynamic, neurohormonal, and pro-inflammatory perturbations, all of which are thought to contribute to donor organ dysfunction. The process of transplantation exposes the donor organ to an obligatory period of ischemia and reperfusion. Traditionally, hypothermic storage of the donor organ has been used to protect it from ischemic injury, but donor organs differ markedly in their capacity to withstand hypothermic ischemia. Data from the Registry of the International Society for Heart and Lung Transplantation indicate that the risk of primary graft failure and death rises dramatically for both the heart and lung as ischemic time increases. Based on these data, maximum recommended ischemic times for the donor heart and lung are 6 and 8 h, respectively. In this chapter, strategies aimed at minimizing the adverse consequences of brain death and ischemia/reperfusion injury to the donor heart and lung are discussed. These strategies are likely to become increasingly important as the reliance on marginal donors increases to meet the growing demand for organ transplantation.