UCSF

Background

In 1997 the FDA approved the first double-red-blood-cell (2RBC) collection device. Soon after, travel deferral for variant Creutzfeldt-Jakob disease (vCJD) risk was adopted. To show the importance of including 2RBCs in predictive models of the blood supply, an existing whole-blood (WB) model was updated to include 2RBC collection and then run to simulate the effect of vCJD deferral on total RBC availability.

Study design and methods

The model simulates donation of allogeneic WB and 2RBCs, with donors stratified into eight age and sex groups. The model was updated with 2003 donation and economic data from 16 blood centers.

Results

The distribution of donations by demographic group differed both within and between WB and 2RBCs. Overall, 2RBC donation made up 24 percent of transfusable RBC units, at a lower per-unit acquisition cost from both the blood bank and the societal perspectives. Component fees from hospitals would alter this interpretation. The model predicts that vCJD travel deferral led to a 3.3 percent (95% confidence interval [CI], 2.3-4.1) decrease in the total number of RBC units, which was more than offset by 2RBC collection, resulting in a 10.4 percent (95% CI, 9.8%-11.1%) net increase in RBC units. Modeled 2RBC results match operational records, whereas vCJD deferral is overestimated.

Conclusion

Shifting to 2RBC collection led to a substantial gain in available RBCs: even with policies that adversely affect the quantity of RBCs in the supply, 2RBC collection results in a net gain. The economics of 2RBC collection are not as clear, however.