Preoperative autologous blood donation and acute normovolemic hemodilution affect intraoperative blood loss during sagittal split ramus osteotomy.

Introduction: This study aimed to determine the effects of acute normovolemic hemodilution (ANH) using low-molecular-weight hydroxyethyl starch (LMW-HES) on intraoperative blood loss in patients who had received preoperative autologous blood donation (PABD) and had undergone sagittal split ramus osteotomy (SSRO).

Methods: Patients who had undergone SSRO were analyzed. All 250 patients received PABD of 400-800 mL until 2 weeks before surgery. ANH was performed by withdrawing whole blood, which was replaced by the same volume of LMW-HES. ANH was performed in 197 cases for 200 mL replacement (ANH-200) and in 5 cases for 400 mL replacement (ANH-400); it was not performed in 48 cases (ANH-0).

Results: Blood loss in ANH-200 was greater than that in ANH-0, despite no differences in hemoglobin concentrations at pre- and post-PABD, prothrombin time, activated partial thromboplastin time, fibrinogen and platelet counts between the groups before surgery. Blood loss increased as the total withdrawn blood (sum of PABD and ANH) increased.

Conclusion: Increased intraoperative blood loss was associated with total withdrawn blood before the operation as well as ANH.