Restrictive versus liberal transfusion thresholds: lights and shadow

Abstract

The hemoglobin threshold below which an anemic patient needs to be transfused is the main questions of modern transfusion medicine and one of the most important issues of patient-centered blood management (PBM) programs. Considering the key function of red blood cells (RBC) in improving tissue and organs oxygenation, for many years a liberal transfusion approach (i.e., transfusion threshold of hemoglobin < 10 g/dL) was the predominant attitude among clinicians that guided transfusion decision-making. More recently, this widely adopted transfusion policy was questioned by a more restrictive (i.e., transfusion threshold of hemoglobin < 7-8 g/dL) approach. Thanks to the results of many randomized controlled trials, systematic reviews and meta-analyses nowadays, most of the international scientific societies and experts currently recommend a restrictive approach over a liberal approach for anemic, hemodynamically stable, patients. However, as not rarely happens in medicine, there are several still unsolved greys areas of uncertainty. These issues will be concisely and critically addressed in this commentary.