Blood Substitute

A blood substitute, also called artificial blood or blood surrogate, is a substance used to mimic and fulfill some functions of biological blood, and in some cases can serve as an alternative to blood transfusion, a therapy using donated blood or blood based products. Blood substitutes that are oxygen carrying are increasingly called oxygen therapeutics, emphasizing their intended primary use in treating severe anemia, and such substitutes must compensate for oxygen's poor solubility, since dissolved oxygen typically accounts for only a fraction of oxygen transport while hemoglobin is the most important oxygen carrier in humans. Two categories of oxygen carrying blood substitutes are being pursued, hemoglobin based oxygen carriers and perfluorocarbon based products, though as of yet there are no standard oxygen therapeutics in use internationally, with several enjoying limited approval for specific applications or undergoing clinical trials in various countries.