An international study published today in the New England Journal of Medicine sheds light on acute normovolemic hemodilution, also known as ANH, a blood conservation technique. ANH involves removing a patient’s blood before the patient goes on heart-lung bypass, and then reinfusing it toward the end of heart surgery. Long debated for its effectiveness, ANH does not appear to reduce the need for red blood cell transfusion, according to results of the global clinical trial. However, study co-author Kenichi Tanaka, M.D., professor and chair of the Department of Anesthesiology at the University of Oklahoma College of Medicine, said the outcomes necessitate further scrutiny and may not be applicable to U.S. patients.