Dominant effect of transfusions on kidney graft survival.

The number of pretransplant blood transfusions influences the graft survival of cadaver kidney transplants more than HLA-A and B matching, preformed lymphocytotoxic antibodies, or center variation. At 1 year the graft survival rate in patients with more than 20 packed cells transfusions was over 30% higher than that in nontransfused recipients (75 +/- 5% versus 41 +/- 2%, P less than 0.0001). Recipients with on packed cell transfusion had a 59 +/- 5% 1-year graft survival rate. Frozen blood and any transfusions given at the time of surgery were relatively ineffective. Pretransplant pregnancies had no significant effect on graft outcome. The improvement effect of transfusions was significant in each of the last four calendar years (1975, P less than 0.001; 1976, P less than 0.01; 1977, P less than 0.0001; 1978, P less than 0.0001). Yet, the percentage of nontransfused recipients has remained almost unchanged over the years. A preliminary survey of transplants done from January to April 1979 showed that one-third of the recipients had not been transfused. A change in transfusion policy is indicated to improve the results of cadaver kidney transplantation.