OBJECTIVES: Open-heart surgery requires cardiopulmonary bypass (CPB) along with transfusions to maintain adequate blood volume. The purpose of this study was to identify the economic impact of using an artificial oxygen carrier instead of blood transfusion in cardiac surgery with CPB at the Mexican Institute of Social Security (know in Mexico as IMSS) from the healthcare payer's perspective. METHODS: A cost-minimization analysis was developed in a randomized clinical trial. Seven patient candidates for cardiac valve replacement received 5 ml/kg of prefluorocarbon (PFC) artificial oxygen carrier during cardiac surgery. They were compared with 11 patients, which received conventional blood transfusions. Clinical, biochemical and hemodynamic parameters, and survival were measured for both groups during hospitalization. Resources and materials used and cost data were obtained from the patients' hospital records for the hospitalization period. RESULTS: Clinical, biochemical and hemodynamic parameters did not show any significant differences between groups. All patients were discharged noting clinical improvement. The hospital stay of the conventional blood transfusion group was 5.55 ± 3.62 days vs. 5.0 ± 0.82 days in the PFC group. The mean per patient cost of blood products in the conventional blood transfusion group was US $993.40, and the PFC group mean per patient cost was US $469.48. The total mean per patient cost during hospitalization in the conventional blood transfusion group was US $31,261.87 ± US $16,239.60. The PFC's total mean per patient cost was US $27,358.90 US ± US $9,671.00 (p=0.57). The difference in cost was US $3902.97 per patient. CONCLUSIONS: The use of PFC has similar clinical outcomes as the use of conventional blood transfusion in cardiac surgery with CPB, and it could present potential savings.