Acute normovolemic hemodilution reduced allogeneic blood transfusion without increasing perioperative complications in patients undergoing free-flap reconstruction of the head and neck

PURPOSE: The present case–control study was conducted to evaluate whether acute normovolemic hemodilution (ANH) can reduce the need for perioperative allogeneic blood transfusion (ABT) and affect the incidence of perioperative complications in free-flap reconstruction of the head and neck. METHODS: This single-center, retrospective, observational study included the perioperative data of 123 patients who underwent free-flap reconstruction of the head and neck following oncological surgery. Patients were divided into the following two groups according to whether they received ANH: ANH group and non-ANH group. We investigated whether ANH can reduce the need for perioperative ABT using propensity score-adjusted logistic regression analysis. RESULTS: Of the 123 patients, 113 patients were assessed; 57 patients were in the ANH group and 56 patients were in the non-ANH group. The rate [ANH group vs. non-ANH group, n (%): 2 (3.5%) vs. 23 (41.1%), p < 0.0001] and amount [median (IQR): 0 mL (0, 0) vs. 0 mL (0, 280), p < 0.0001] of ABT were significantly lower in the ANH group than in the non-ANH group. Propensity score-adjusted multivariate logistic regression analysis indicated that ANH use [odds ratio (OR): 0.040; 95% confidence interval (CI) 0.005, 0.320; p = 0.0024)] was one of the independent predictors of perioperative ABT. There were no significant differences in the incidences of post-operative complications between the two groups. CONCLUSION: ANH use can reduce the need for perioperative ABT in patients undergoing free-flap reconstruction of the head and neck without increasing the incidence of post-operative complications.