Abstract

Objective

Priming solutions used during cardiopulmonary bypass may cause hemodilution, resulting in decreased perioperative hematocrit levels and increased transfusion requirements. This study aimed to evaluate the effects of retrograde autologous priming (ROP), particularly ROP volume, on hematocrit trajectory, red blood cell transfusion requirements, and clinical outcomes in patients undergoing isolated coronary artery bypass grafting (CABG).

Materials and Methods

Eighty adult patients who underwent isolated CABG were retrospectively analyzed. The patients were divided into two groups according to ROP use: ROP (-) (n = 40) and ROP (+) (n = 40). Demographic characteristics, perioperative variables, hematocrit levels, clinical outcomes, and red blood cell transfusion amounts were compared. ROP volume was recorded as a continuous variable. The Mann–Whitney U test, chi-square test, Spearman correlation, and multivariable linear regression analyses were used.

Results

The duration of mechanical ventilation was significantly shorter in the ROP (+) group (p = 0.023). The total red blood cell transfusion requirement was significantly lower in the ROP (+) group (median 1.0 vs. 3.5 units; p = 0.001). ROP volume was positively correlated with post–aortic cross-clamp hematocrit levels (ρ = 0.458; p < 0.001) and negatively correlated with total red blood cell transfusion amount (ρ = −0.298; p = 0.007). In the multivariable linear regression analysis, ROP volume remained independently associated with post–cross-clamp hematocrit levels (β = 0.232; p = 0.044).

Conclusion

ROP contributes to the preservation of post-bypass hematocrit levels and the reduction of red blood cell transfusion requirements in isolated CABG. The observed effect appears to depend not only on whether ROP is used but also on the volume of autologous blood applied.