Acute Normovolemic Hemodilution in Surgery

Acute normovolemic hemodilution (ANH) is a technique in which whole blood is removed from a patient while the circulating blood volume is maintained with acellular fluid shortly before a surgical procedure that is anticipated to result in significant blood loss. While this technique was studied and developed over 25 years ago [1], ANH is today seldom practiced and remains controversial [2,3], despite recommendation of its use by consensus statements such as an expert panel [4] of the National Heart, Lung, and Blood Institutes. The purpose of this review is to address recent advances in the understanding of this blood conservation stratergy, along with its emerging role in autologous blood procurement strategies.