The Marginal Donor

A plethora of articles has been written on the issue of the "marginal donor," i.e., any donor who for age, body habitus, past medical history, unstable hemodynamics and length of stay in the hospital represents a potential risk of posttrans-plant organ dysfunction and would not assure the same consistency of patient and graft survival as the ideal donor.26,32-35 The use of these donors is somewhat justified by the ever-increasing gap between the number of patients on the waiting list for organ transplantation and the number of available donors. It must be also stated that with a positive assessment of the organ and excellent technique in the retrieval by the accepting transplant surgeon, the risk of transplanting an organ that will not function can be minimized and patient and graft survival can match the ones of the patients who received organs from ideal donors. The almost general consensus is that, although it is clear that there is a decreased graft survival rate of an average of 10% at 5 years when marginal donors are used, this is counterbalanced by a greater number of patients who undergo transplantation with nonideal organs, do well and return to a normal life. With the increasing number of patients dying while on the transplant waiting list we cannot limit donations to only "ideal donors." The use of marginal donors is now the norm in any large transplant institution. At times, when relying solely on the information collected by the organ procurement coordinator, it is very difficult to decide whether a potential donor is acceptable. In these cases of uncertainty the personal, visual I and tactile assessment of the donor surgeon correlates with graft survival better Ej than any other objective test, and it has been shown to be the only variable signifi- ® cantly correlating to the quality of the retrieved liver.35,36 As a rule of thumb: the surgeon should retrieve all organs which are not clearly unusable and obtain biopsies that should be read at the home institution together with a senior pathologist with expertise in that particular organ system. The use of routine biopsies in kidneys from nonideal donors has not increased the number of available organs but has greatly helped in discarding the ones that for unacceptable degree of glomerulosclerosis, > 10-20%, presence of interstitial fibrosis and arteriolar changes would have been at great risk of poor function. Interesting reports of good results (actuarial 1 year graft survival of 100%) with the transplant of the two kidneys from a marginal donor in the same recipient may increase the acceptance criteria to include older donors with up to 30% of glomerulosclerosis or frozen section.37

Small Bowel

Intestinal transplantation is still in its early era and so no recognized guidelines in the selection of the donors exist. Overall, the same criteria outlined above for the liver are utilized for the small bowel donor, also considering that at the present time most intestinal transplants are performed in combination with the liver. At our institution we consider a potential donor for bowel transplant a person less than 45 years of age, nonobese, CMV negative and of the same blood group of the recipient. With increasing experience in this field some of these criteria, like the blood group barrier, may prove not to be such a determinant in the outcome of the intestinal transplant recipients.38-40

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