Transfusion requirements after cardiac surgery: the TRACS randomized controlled trial

Area of Science:

• Cardiology
• Transfusion Medicine
• Critical Care Medicine

Background:

• Anemia is a significant risk factor for morbidity and mortality following cardiac operations.
• Optimal blood transfusion practices in cardiac surgery patients remain unclear.
• Perioperative red blood cell transfusion is a common intervention for anemia.

Purpose of the Study:

• To compare the safety of a restrictive versus a liberal perioperative red blood cell transfusion strategy.
• To determine if a restrictive strategy is non-inferior to a liberal strategy in elective cardiac surgery patients.

Main Methods:

• Prospective, randomized, controlled noninferiority trial (TRACS study).
• 502 adult patients undergoing cardiac surgery with cardiopulmonary bypass.
• Random assignment to either a restrictive (hematocrit ≥24%) or liberal (hematocrit ≥30%) transfusion strategy.

Main Results:

• Mean hemoglobin was 9.1 g/dL in the restrictive group vs. 10.5 g/dL in the liberal group (P < .001).
• Transfusion rates were 47% (restrictive) vs. 78% (liberal) (P < .001).
• The primary endpoint (30-day mortality and severe morbidity) occurred in 11% of the restrictive group and 10% of the liberal group (P = .85).

Conclusions:

• A restrictive perioperative transfusion strategy is non-inferior to a liberal strategy in patients undergoing cardiac surgery.
• This finding supports the use of restrictive transfusion practices to potentially reduce unnecessary transfusions.
• The number of transfused red blood cell units independently predicted 30-day complications or death.