Red blood cell be used for blood transfusions. Several blood tests involve red blood cells. These include a "RBC count" (the number of red blood cells per volume of blood), calculation of the hematocrit (percentage of blood volume occupied by red blood cells), and the erythrocyte sedimentation rate. The blood type needs to be determined to prepare for a blood transfusion or an organ transplantation. Many diseases involving red blood cells are diagnosed with a blood film (or peripheral blood smear), where a thin layer of blood is smeared on a microscope slide. This may reveal abnormalities of red blood cell shape and
Neonatal red cell transfusion baby (e.g. wristband). Paedipacks are multiple aliquots made from one adult blood donation. By using paedipacks, the baby is exposed to blood from fewer blood donors. ABO blood grouping and screening for antibodies in neonates differs from blood grouping in adults and older children. Any antibodies detected are the mother's antibodies rather than the baby's. Therefore, any donor blood given to the baby must be ABO and D compatible with both mother and baby; and antigen-negative for any clinically significant maternal antibodies. Necrotising enterocolitis may occur after a red cell transfusion in neonates, although there is an association between the