TUESDAY, Sept. 9, 2025 (HealthDay News) -- Acute normovolemic hemodilution (ANH) lowers the need for transfusions during cardiopulmonary bypass surgery but is underused in the United States, according to a study published online Sept. 3 in JAMA Surgery.Kenichi A. Tanaka, M.D., from University of Oklahoma Health Sciences Center in Oklahoma City, and colleagues conducted a retrospective cohort study to evaluate ANH use in perioperative transfusion and blood component use in patients undergoing surgery with cardiopulmonary bypass. The analysis included 16,795 patients identified from the Society of Thoracic Surgeons Adult Cardiac Surgery Database.The researchers found that 2,463 patients received ANH (14.7 percent). Patients receiving ANH had a significantly lower preoperative anemia rate and higher baseline hematocrit (mean difference: 2.5 percent). For 2,282 propensity score-matched pairs, transfusion rates were significantly lower in the ANH group (31.2 versus 36.4 percent). ANH was associated with lower odds of any transfusion (odds ratio, 0.73), with odds of transfusion further reduced with high-volume ANH (≥650 mL; by 47 to 64 percent for both red blood cell and non-red blood cell components). In the ANH group, the cumulative number of transfused erythrocyte and platelet units was 167 and 295 units lower, respectively, versus the control group and was associated with lower costs."Even a small reduction in blood usage could significantly impact overall demand, particularly given the rising cost of blood components and the more than 300,000 adult cardiac surgical cases performed annually in the United States," Tanaka said in a statement.Several authors disclosed ties to industry.Abstract/Full Text (subscription or payment may be required)Editorial (subscription or payment may be required).Sign up for our weekly HealthDay newsletter