Blood substitutes
The substitutes of blood do not possess all the physiological properties as natural blood however, in emergencies and in certain physiological disorders following blood substitutes prove to be life saving.
1)   Packed red cells – can be transfused when oxygen carrying capacity is to be increased without increasing blood volume.
2)Â Â Â Fresh frozen plasma- is used for infusion in oligemic shock i.e. in burn cases.
3)Â Â Â Dextran- isolated from beet sugar is used in treatment of shock.
4)Â Â Â Human serum albumin- is used to reduce edema and to raise level of protein in hypoproteinemia.
5)Â Â Â Pure hemoglobin- is used for transfusion without being matched for blood group and compatibility.
6)Â Â Â Per fluorocarbons- is used in patients allergic to normal transfusions and in cases of carbon monoxide poisoning.
7)   Genetic engineers have introduced two human hemoglobin genes into the brewers yeast “Sacchromyces cerivicae” and into E. coli and pigs and made them produce large amounts of human hemoglobin.
8)Â Â Â Â Autologous blood transplant- recent trend is normal healthy person preparing for operations give their own blood in advance. It is prepared by new blood freezing technique and can be transfused during emergency. This prevents AIDS .