Anemia 2: Patofisiology

Patofisiology Anemia

In the first few weeks of pregnancy yolk sac is the main hemopoesis. Then in 6 weeks to 6 - 7 months of life fetus, liver and spleen are the main organs that are required and both continue to produce blood cells until about 2 weeks after birth. During the normal children and adults, bone marrow is the only source of new blood cells. Bone marrow is a suitable environment for growth and development of stem cell hemopoetik pluripoten which is the origin of all cells in the blood circulation and is also equipped by stroma cells, fat cells and tissue mikrovaskuler. (Petit, J.E., 1996).

Red blood cells produced from stem cell has the main components of the hemoglobin to carry oxygen to function tissue and restore the network of carbon dioxide to the lungs and also maintain the normal pH through a series in intracellular. (Guyton, AC, Hall, JE, 1997) and (Petit, JE, 1996).
Hemoglobin molecule-molecule consists of 2 pairs of chain polypeptide (globin) and 4 truss hem, each containing an iron atom. (Baldy, C.M., 1995).

The number of red blood cell is approximately 5 million cubic / millimeter blood on the average adult and aged 120 days. Still maintained a balance between loss and replacement of blood cells every day. The formation of red blood cells by this stimulated hormone glikoprotein and eritropoetin. Eritropoetin influenced by the formation of hypoxia network that is affected by factors such as changes in O2 atmosphere, the reduced arterial blood O2 content and the reduced hemoglobin concentration. Eritropoetin stimulate stem cell proliferation and to start the maturation of blood cells-red cells, further maturation depend on the number of substances-substances that enough food and the use of suitable, such as vitamin B12, folat acid and minerals such as iron. (Petit, J.E., 1996).

Vitamin B12 and acid folat is a co-enzyme needed for DNA production, so that when the going defisiensi against both maturation will lead to disruption of the cell nucleus will prevent mitosis. These conditions cause damage to some nucleus red blood cells in the bone marrow and the occurrence of disproportion between the core and cytoplasm's red blood cells with nucleus (megaloblas).
(www.mosby.com / Merlin / Huether).

Time ripen red blood cells, these cells become more rigid and more brittle, and eventually broken. Hemoglobin fagositosis especially in the spleen, liver and bone marrow, and then become reeducated hem and globin, globin re-entry into the source of amino acids. Iron released from most of the hem and transported by plasma proteins transferin in bone marrow for the establishment of new red blood cells. The remaining iron is stored in the liver and the body of another network in the form of hemosiderin and feritrin, this reserve will be used again later days. Remaining to be shirt redukted carbon monoxide (CO), which will be issued through pulmos tuberculosis and biliverdin, which then become redukted free bilirubin, which is slowly released into the plasma, which joined the bilirubin plasma albumin and then transported into the cells into the liver for excresion with canalikuli bile. When there is devastation active cells such as red blood hemolisis, the exemption amount of bilirubin into a fast liquid extracellular cause skin look yellow (ikterus). (Guyton, A.C., Hall, J.E., 1997)

The incidence of anemia may be the mechanism through which the track and in the development and circulation of red blood cells so that the required depth of understanding about the physiology of this red blood cell. (Baldy, C.M., 1995).