From Risk to Cost: Red Blood Cell Transfusion Predictors and Economic Burden in Cardiac Surgery

Abstract

Objectives: Identify predictors of RBC transfusion in cardiac surgery and estimate its economic burden. Design: Retrospective cohort study. Setting: Single-center, tertiary hospital in Portugal. Participants: 661 adults undergoing elective cardiac surgery from April 2020 to April 2021. Interventions: None. Measurements and Main Results: Primary outcome: RBC transfusion. Secondary outcomes: 30-day mortality, infection, AKI, prolonged mechanical ventilation, ICU stay, and total hospital LOS. Multivariable analysis identified preoperative anemia (ORadj 3.67, 95% CI 2.00-6.74), female sex (ORadj 2.06, 95% CI 1.22-3.48), higher EuroSCORE II (ORadj 1.15, 95% CI 1.03-1.29), longer cardiopulmonary bypass time (ORadj 1.01, 95% CI 1.00-1.02), lower intraoperative nadir hemoglobin (ORadj 0.48, 95% CI 0.40-0.58), and higher 12-hour postoperative bleeding (ORadj 1.003, 95% CI 1.002-1.004) as predictors. Unexpectedly, surgical complexity was associated with lower transfusion risk (ORadj 0.73, 95% CI 0.54-0.99). Transfused patients had longer hospital LOS (median 10 vs. 8 days, IQR 7-12 vs. IQR 8-16), with a 40.5% increase (Exp(B) = 1,405, 95% CI: 1,256-1,572). This relation lost statistical significance after adjusting for postoperative infection and prolonged ventilation. Incremental cost per transfused patient was €2.264,44 (p < 0.001). Eliminating preoperative anemia could reduce 47 transfusions, 94 hospital days, and save 106.429,00€ over 13 months. Conclusions: RBC transfusion is associated with increased LOS and costs. Preoperative anemia remains the strongest predictor, reinforcing the need for Patient Blood Management in cardiac surgery.