During massive transfusion, i.e. a patient receiving 10 or more red cell bags within 24 hours, the patient’s total circulation is replaced with donor blood. Note that subsequent serum samples will contain very little of the patient’s original blood serological profile. Stored blood contains minimal plasma/ platelets, shock also disturbs blood coagulation. (note: all patients born after 1 January 1996 must be identified as they must be issued with non UK sourced plasma. This is a DOH directive.)