Hemoglobin solutions as oxygen-delivering resuscitation fluids

Human hemoglobin (Hb) solution is being developed for use as an oxygen-delivering resuscitation fluid. Substantial improvements in the general purity and quality of experimental Hb solutions have been achieved by recent research efforts. Hb solutions now appear to be free of the undesirable biological effects that were reported in earlier studies. The present product, furthermore, is suitable for prolonged storage and can be dehydrated for greater efficiency in shipping and stockpiling during emergencies. Such improvements have enabled investigators to study the potential resuscitative properties of hemoglobin solutions in vivo, in experimental animals. From recent investigations, a reasonable picture of the limitations as well as a knowledge for potential improvements has evolved. Limitations are insufficient intravascular hemoglobin retention and increased oxygen affinity of free Hb, as compared to intraerythrocytic Hb. Potential improvements that could overcome these limitations may be achieved by modifying Hb to maintain the tetrameric molecule, thus providing a stable Hb compound having longer intravascular life as well as lower oxygen affinity.