Cardiac surgery or cardiovascular surgery is a surgery of the heart or great vessels performed by cardiac surgeons. In patients undergoing cardiac surgery who are at moderate-high risk for death, both restrictive and liberal transfusion strategies can be used to improve the surgery outcomes. This study aims to compare the clinical outcomes of restrictive and liberal transfusion for cardiac surgery.

This randomized trial included a total of 5,243 adults undergoing cardiac surgery. The patients were randomly assigned to a restrictive red-cell transfusion surgery or a liberal red-cell transfusion surgery. The primary outcomes of the study were all-cause mortality, stroke, myocardial infarction, or new-onset renal failure. Secondary outcomes were individual components of the primary outcomes.

At 6 months of follow-up after surgery, primary outcomes were reported in 402 patients (17.4%) in the restrictive transfusion group and 402 patients (17.1%) in the liberal transfusion group. The rate of mortality was 6.2% in the restrictive transfusion group and 6.4% in the liberal transfusion group. No differences in the individual components of the aforementioned primary outcomes were found.

The research concluded that in patients undergoing cardiac surgery, restrictive transfusion was non-inferior to liberal transfusion with respect to the composite outcomes of mortality, cardiovascular outcomes, and renal diseases.