The effects of fetal exchange transfusion with a red blood cell substitute.

Isovolemic exchange transfusion in the fetal lamb in utero was performed with the use of Fluosol-DA (20%), a perfluorochemical erythrocyte substitute. With maternal hyperoxygenation, a physiologic PO2 was maintained in the fetal lambs, although the total fetal oxygen content decreased as the hematocrit dropped. Because of the oxygen-carrying properties of the perfluorochemical emulsion, the fraction of fetal oxygen carried in the dissolved state increased significantly when compared with that in controls that received saline solution.