<P> Side effects include allergic reactions such 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 . Packed red blood cells are gotten from whole blood or by apheresis . They typically last for three to six weeks . </P> <P> 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 a health system . In the United Kingdom they cost about 120 pounds per unit . A number of other versions also exist including whole blood, leukocyte reduced red blood cells, and washed red blood cells . </P> <P> Blood transfusion is typically recommended when hemoglobin levels reach 70 g / L (7 g / dL) in those who have stable vital signs . For those with heart disease or having surgery it is recommended at 8 g / dL . </P> <P> RBCs are used to restore oxygen - carrying capacity in people with anemia due to trauma or other medical problems, and are by far the most common blood component used in transfusion medicine . Historically they were transfused as part of whole blood, are now typically used separately as RBCs and plasma components . The process of identifying a compatible blood product for transfusion is complicated . </P>

How many ml in packed red blood cells