donors, from whom all solid organs can be taken, rose, in terms of not only organs procured per donor (21%, from 2.98 to 3.60) but as organs actually transplanted per donor (18%, from 2.73 to 3.21 from 1988 to 1996)* (OPTN/Scientific Registry data as of April 15, 1997). Unfortunately, no improvement in the organ-per-donor figures has occurred since 1993, and the organ-per-donor yield for NHBDs is, and likely will remain, lower as that category is expanded (2.5 organs-per-donor, and 1.78 transplants-per-donor, aggregate from 1993 to 1996) (M. Ellison, personal communication, June 27, 1997).
These comparative numbers of transplants or recipients per donor should be part of an assessment of supply and demand. Also the success of transplantation—the survival of the transplanted organ and the recipient patient—depends heavily on the condition of the donor organ (Cosio et al., 1997; Light et al., 1996; Jacobbi et al., 1997). The expansion of criteria for acceptance of organs from donors of greater age and in less satisfactory medical conditions and the increased use of NHBDs exact a price in increased procurement costs of 23% more per donor and thus even more per organ (L. Jacobbi, personal communication, July 17, 1997); increased cost of transplantation; and lower graft (i.e., the transplanted organ) and recipient survival (Alexander et al., 1994; Briceno et al., 1997; Casavilla et al., 1996; Jacobbi et al., 1997; Light et al., 1996; Whiting et al., 1997). This must be weighed against the morbidity, death, and economic and other costs in patients on the waiting list (Hauptman and O'Connor, 1997; Perkins, 1987; Light et al., 1996).
Regardless of donor type, overall patient and graft survival rates have continued to improve over time. One-year graft survivals now range from 74% to 92% depending on the organ, although in subsequent years survivals gradually decrease particularly in expanded donor and NHBD transplants. The best results are with kidneys, which comprised 51% of all cadaver transplants and 98% of all living donor transplants in 1996 (OPTN/Scientific Registry data as of July 5, 1997). Coincident with improvements in the technology available and these better results, the pool of potential recipients has been expanding steadily (Anaise and Rapaport, 1993). These trends are likely to continue.
Changes in supply should be compared with changes in demand. The transplantation waiting list contained 50,047 people waiting on the last day of 1996, 14% more than the previous year and 212% more than at the end of 1988
The difference between organs procured and organs transplanted (the discard rate) is the loss caused primarily by various medical and viability problems in removed organs that makes them unsuitable for transplantation. Greater use of donors accepted under expanded criteria and NHBDs is causing a rising discard rate.