Red blood cell blood circulation for about 100 to 120 days (and 80 to 90 days in a full term infant). At the end of their lifespan, they are removed from circulation. In many chronic diseases, the lifespan of the red blood cells is reduced. Erythropoiesis is the process by which new red blood cells are produced; it lasts about 7 days. Through this process red blood cells are continuously produced in the red bone marrow of large bones. (In the embryo, the liver is the main site of red blood cell production.) The production can be stimulated by the hormone erythropoietin (EPO),
Packed red blood cells as anaphylaxis, red blood cell breakdown, infection, volume overload, and lung injury. With current preparation methods in the developed world the risk of viral infections such as hepatitis C and HIV/AIDS are less than one in a million. However, the risks of infection are higher in low income countries. Packed red blood cells are produced from whole blood or by apheresis. They typically last for three to six weeks. The widespread use of packed red blood cells began in the 1960s. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in