A new resuscitation fluid "stabilized hemoglobin" preparation and characteristics

A new oxygen carrier for use as a blood substitute was prepared and characterized in vitro. Pyridoxylated hemoglobin, which was obtained by the reaction of human hemoglobin with pyridoxal-5-phosphate, was modified by alpha-carboxymethyl, omega-carboxymethoxyl polyoxyethylene (POE) of the molecular weight 3600 daltons. In order to eliminate viruses and nucleic acids possibly contaminated, the hemoglobin solution was purified by ultrafiltration with a membrane of the nominal molecular weight limit 300 Kdaltons. Furthermore POE conjugated pyridoxylated hemoglobin was treated with 20% ethanol to inactivate viruses. A concentration of hemoglobin, which is incorporated in the conjugate, of the final product was fixed at 6% to make normovolemic exchange transfusion possible. In consideration of the stability during transporting and storage, lyophilized product was selected as a final form ("Stabilized Hemoglobin"). "Stabilized hemoglobin" could be stored in a refrigerator over one year within the acceptable methemoglobin increase. (15%) Viscosity of Stabilized Hemoglobin solution was determined at 2.4 centipoise and is almost half of whole blood and therefore this will be useful not only in resuscitation but also in improvement of microcirculation.