[Preoperative anemia : a review of its prognostic implications, diagnosis and management]

About 30 % of patients scheduled for surgery present with preoperative anemia. The presence of preoperative anemia increases the likelihood of exposure to allogenic blood transfusions, which carries specific complications. Furthermore, and independently of the transfusion risk, it is associated with an increased risk of postoperative morbidity and mortality. It is now recommended to treat preoperative anemia whenever possible. This article summarizes the prognostic implications of preoperative anemia and proposes a diagnostic and therapeutic strategy for the most common clinical situations. Finally, it illustrates how collaboration between primary care and hospital medicine can provide patients with effective and personalized treatment without the need to alter the surgical planning.