Mazer CD, et al. - Considering that a restrictive transfusion strategy as noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis by hospital discharge or 28 days after surgery, whichever came first among patients undergoing cardiac surgery who were at moderate-to-high risk for death, researchers presented the clinical outcomes at 6 months after surgery. Findings support the noninferiority of restrictive strategy for red-cell transfusion to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis at 6 months after surgery among these patients.

Methods

• Researchers performed random assignment of 5243 adults undergoing cardiac surgery to a restrictive red-cell transfusion strategy (transfusion if the hemoglobin concentration was <7.5 g per deciliter intraoperatively or postoperatively) or a liberal red-cell transfusion strategy (transfusion if the hemoglobin concentration was <9.5 g per deciliter intraoperatively or postoperatively when the patient was in the intensive care unit [ICU] or was <8.5 g per deciliter when the patient was in the non-ICU ward).
• Death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis occurring within 6 months after the initial surgery were assessed as the primary composite outcomes.
• All the components of the primary outcome as well as Emergency Department visit, hospital readmission, or coronary revascularization occurring within 6 months after the index surgery were included in the expanded secondary composite outcomes.
• The individual components of the two composite outcomes were included as the secondary outcomes.

Results

• The primary composite outcome were noted in 402 of 2317 patients (17.4%) in the restrictive-threshold group and in 402 of 2347 patients (17.1%) in the liberal-threshold group at 6 months after surgery (absolute risk difference before rounding, 0.22 percentage points; 95% confidence interval [CI], −1.95 to 2.39; odds ratio, 1.02; 95% CI, 0.87 to 1.18; P=0.006 for noninferiority).
• The restrictive-threshold group had mortality of 6.2% vs 6.4% in the liberal-threshold group (odds ratio, 0.95; 95% CI, 0.75 to 1.21).
• The groups were not significantly different in terms of the secondary outcomes.