Acute normovolemic hemodilution (ANH) and retrograde autologous priming (RAP) are blood conservation techniques designed to reduce transfusion requirements.

This study evaluated the impact of combining ANH and RAP compared to RAP alone on intraoperative packed red blood cell (PRBC) transfusion and postoperative outcomes in coronary artery bypass grafting (CABG) surgery.

A single-center randomized controlled trial.

72 patients scheduled for CABG surgery from July 2024 to December 2024 at the National Cardiovascular Center Harapan Kita in Indonesia. Patients were randomly assigned to ANH + RAP group (n = 36) and RAP group (n = 36).

Multivariate analysis assessed factors influencing final hemoglobin levels and intraoperative PRBC transfusion needs.

The ANH + RAP group experienced a significant reduction in the transfusion rate (19.4% vs 47.2%, p = 0.024) and the intraoperative allogeneic packed red blood cell units (0.2 ± 0.4 vs 0.5 ± 0.6, p = 0.012). The optimal ANH volume reduces intraoperative allogeneic PRBC transfusion was 380 mL (ROC area 0.862, 95% CI 0.703–1.000, p = 0.003). Single RAP procedure approaches were less effective when compared to the combination procedure for achieving higher final hemoglobin levels (β = −0.824, 95% CI −1.314 to −0.334, p = 0.001) and reducing the likelihood of intraoperative allogeneic PRBC transfusion (OR = 13.370, 95% CI 2.206 to 81.026, p = 0.005). Postoperative outcomes did not differ between groups.

The combined use of ANH and RAP significantly reduces intraoperative allogeneic PRBC needs compared to RAP alone without affecting postoperative outcomes.