Preoperative autologous donation decreases allogeneic transfusion but increases exposure to all red blood cell transfusion -: Results of a meta-analysis

Background: Concern about risks associated with allogeneic red blood cell transfusion has led to interest in methods of decreasing patient exposure to perioperative transfusion. Objective: To perform a meta-analysis to determine the degree to which predonation of autologous blood reduces patients' exposure to allogeneic blood and all transfusions of red blood cells (allogeneic or autologous). Methods: We searched MEDLINE, EMBASE, bibliographies, annual reports, press releases, newsletters from organizations with interests in the blood system, and personal files for randomized studies and concurrent control cohort studies in which the control groups were patients excluded for nonmedical reasons. Results: Patients who predonated autologous blood were less likely to receive allogeneic blood in the 6 randomized studies (n=933) (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.08-0.32) and in the 9 cohort studies (n=2351) (OR, 0.19; 95% CI, 0.14-0.26). However, autologous donors were more likely to undergo transfusion with allogeneic and/or autologous blood (for randomized studies: OR, 3.03; 95% CI, 1.70-5.39 and for cohort studies: OR, 12.32; 95% CI, 5.90-25.40). Studies that reported use of transfusion protocols found less benefit with preoperative autologous donation, although the difference was not statistically significant. Conclusions: Preoperative autologous donation of blood decreases exposure to allogeneic blood but increases exposure to any transfusion (allogeneic and/or autologous). There is a direct relationship between the transfusion rate in the control group and the benefit derived from preoperative autologous donation. This suggests that other methods of decreasing blood transfusion, such as surgical technique and transfusion protocols, may be as important as preoperative autologous donation of blood.