The transfusion of a single unit of red blood cells significantly increases total hospital costs in adult, non-cardiac surgical patients.

We aimed to quantify the financial impact of a single red blood cell (RBC) unit transfusion. We included all adult patients who underwent elective non-cardiac surgery from 2014 to 2021 and received either none or a single RBC transfusion. Clinical and economic data were retrieved from electronic records and billing systems using a bottom-up, micro-costing approach, including 80,944 surgical admissions. Mean age was 60.6 ± 18.1 years, 40,541 (50.1%) were female, and 27,661 (34.2%) were classified ASA score ≥ 3. In total, 2,727 (3.4%) patients received an RBC transfusion. The average length of stay was 6.3 ± 9.2 days. The most common surgical specialty was orthopedics, followed by general surgery. Unadjusted analyses revealed higher costs in the transfused group. After adjusting for age, sex, ASA score, preoperative hemoglobin value, length of stay and hospital site, the hospital costs were USD 11,724 (IQR 3,481 − 21,872) compared to USD 11,233 (IQR 6,736 − 19,336) in the non-transfused group (p = 0.018). RBC transfusions represent a significant economic burden in adult elective non-cardiac surgical patients. Regardless of its appropriateness, each transfusion increased hospital costs by an average of USD 491 compared to non-transfused patients, corresponding to 5.2% of the median total hospital cost. Patient blood management policies should be implemented in hospital trusts to minimize transfusion rates in elective surgery.