A search for a substitution for human blood began in the 1940's whan a great need for it became evident in World War Two. This need increased in the 80's when viruses such as HIV and Hepatitus B and C emerged. The ideal blood substitute would carry oxygen, increase blood volume, work on patients with varied blood types, be storable for greater lengths of time than human blood, lack the risk of disease, be able to be produced in mass quantities and have a moderate to low price.
However, the complexity of blood with its many components serving so many purposes have prevented researchers from producing a complete, artificial blood substitute. Yet, partial and experimental blood substitutes that can assist with specific functions alone, (such as the transportation of oxygen or battling an infection,) have proved useful.
Blood Substitutes are used when a patient has endured significant blood loss or is, for other reasons, deficient in certian areas regarding their blood. Reasoning for not using donated blood extends from a violation of a patients religious belifs to the risk of blood borne diseases and from the inability to keep whole, human blood for longer than roughly 35 days to a lack of donated blood. Substitutes for blood have therefore been discovered and produced; these include Fluosol, Chemically Altered Hemoglobin, Neohemocytes and Hemopure.