Packed red blood cells Whereas in high-income countries, most blood transfusions are given to people over 65 years of age (up to 76%). In these countries transfusion are most commonly used for supportive care in heart surgery, transplant surgery, massive trauma, and therapy for solid and blood cancers. Due to changes in surgical practices, medical use of blood is now the major use of red blood cells in high-income countries. 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 it is recommended at 80g/L (8 g/dL). RBCs are
Red blood cell form. When red blood cells sometimes occur as a stack, flat side next to flat side. This is known as "rouleaux formation", and it occurs more often if the levels of certain serum proteins are elevated, as for instance during inflammation. Red blood cells can be obtained from whole blood by centrifugation, which separates the cells from the blood plasma in a process known as blood fractionation. Packed red blood cells, which are made in this way from whole blood with the plasma removed, are used in transfusion medicine. During plasma donation, the red blood cells are pumped back into