The purpose of this study is to see if restoring important energy molecules (ATP and 2,3,DPG) in stored red blood cells before they are transfused, with a rejuvenating solution (Rejuvesol), offers any advantages to individuals over standard blood transfusion. This is a Food and Drug Administration (FDA) approved process that is described by the American Association of Blood Banks for prolonging blood storage but not used for everyday transfusions. The investigators want to use this process to improve blood transfused to individuals who need frequent transfusions. Potential advantages include better delivery of oxygen by the transfused red blood cells and easier release of oxygen to the tissues. In addition the study will assess how using the rejuvenated blood affects the interval between transfusions. This means possibly that transfusions may not be needed as often.