Red cell substitutes: hemoglobin solution or fluorocarbon?

Stroma-free hemoglobin (SFH) and Fluosol-DA (FL-DA) are the two acellular oxygen carriers that represent potential red cell substitutes. Although both can support life at zero hematocrit, their effectiveness as O2 carriers at intermediate hematocrits has been unclear. In the presence of red cells, the efficacy of an acellular O2 carrier can be assessed by its contribution to O2 delivery and O2 consumption. This study evaluated the efficacy of SFH and FL-DA in the presence of red cells at hematocrits less than or equal to 10%. The results illustrate that SFH and FL-DA do contribute to O2 delivery and O2 consumption in the presence of red cells. The data indicate that SFH and FL-DA are both effective acellular O2 carriers.