Impaired Red Blood Cell Deformability after Transfusion of Stored Allogeneic Blood but Not Autologous Salvaged Blood in Cardiac Surgery Patients Osman N. Salaria, MD,* Viachaslau M. Barodka, MD,* Charles W. Hogue, MD,* Dan E. Berkowitz, MD,*† Paul M. Ness, MD,‡ Jack O. Wasey, MD,* and Steven M. Frank, MD* BACKGROUND: Both cardiopulmonary bypass (CPB) and red blood cell (RBC) storage are associated with detrimental changes in RBC structure and function that may adversely affect tissue oxygen delivery. We tested the hypothesis that in cardiac surgery patients, RBC deformability and aggregation are minimally affected by CPB with autologous salvaged blood alone but are negatively affected by the addition of stored allogeneic blood. METHODS: In this prospective cohort study, 32 patients undergoing cardiac surgery with CPB were divided into 3 groups by transfusion status: autologous salvaged RBCs alone (Auto; n  =  12), autologous salvaged RBCs + minimal (