<Tr> <Th> ChemSpider </Th> <Td> <Ul> <Li> none </Li> </Ul> </Td> </Tr> <Ul> <Li> none </Li> </Ul> <P> Packed red blood cells, also known as red cell concentrate and packed cells, are red blood cells that have been separated for blood transfusion . They are typically used in anemia that is either resulting in symptoms or when the hemoglobin is less than 70--80 g / L (7--8 g / dL). One unit brings up hemoglobin levels by about 10 g / L (1 g / dL). Repeated transfusions may be required in people receiving cancer chemotherapy or who have hemoglobin disorders . Cross matching is typically required before the blood is given . It is given by injection into a vein . </P> <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>

What is packed red blood cells for transfusions
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