الفهرس | Only 14 pages are availabe for public view |
Abstract Blood transfusion has been the solution for many disorders that affect the integrity of the circulatory system as well as the respiratory system in the way that includes oxygen carriage and delivery to tissues. Blood transfusion unfortunately has many drawbacks and complications e.g.: may be unavailable during crisis and emergency situations, non-compatible blood can cause serious reactions, carries the risk of contamination and spreading dangerous illnesses. Due to these disadvantages and the already low supplies of fresh blood and the costs and efforts done to screen and prepare safe blood, scientists and researchers worldwide have been trying to produce substances that can perform the different functions of blood and these substances have to be safer, more plentiful, available and if possible cheaper than regular blood or blood components. Generally, these products are called blood substitutes.These products have undergone a lot of development and available products are classified into: perfluorocarbon emulsions, hemoglobin based oxygen carriers. Summary - 119 - Perfluorocarbons emulsions are completely synthetic inert products and are mainly classified into first and second generations. Hemoglobin based oxygen carriers use modified hemoglobin, conjugated hemoglobin, polymerized hemoglobin or encapsulated hemoglobin as the oxygen carrier. White blood cells however don’t have a substitute yet, except growth factors like: G-CSF (Granulocyte colony stimulating factor) that stimulate their production and maturation. G-CSF stimulates the production of white blood cells. In oncology and hematology, a recombinant form of G-CSF is used with certain cancer patients to accelerate recovery from neutropenia after chemotherapy. Further studies are currently underway for this exciting new class of drugs. The use of recombinant myeloid colony stimulating factors (CSF) such as G-CSF has also improved care of patients with severe leucopenia, allowing for increased production of endogenous myeloid cells. Platelet substitutes are also available to restore platelet count and function in thrombocytopenic and thrombocytopathic patients. These substitutes are either fully synthetic or derived from outdated or modified platelets Summary - 120 - Platelet substitutes include: fibrinogen-coated albumin microcapsules (FAMs), infusible platelet membranes which are produced from outdated human platelets, red cells with surface-bound fibrinogen, lyophilized human platelets, freeze dried platelets, platelet derived microparticles, factor Xa with phospholipid vesicles and platelet growth factors. |