Blood transfusion study in patients at risk for cardiac complications after non-cardiac surgery.

Topic:

Anemia is a common condition in the perioperative phase and is associated with worse postoperative
cardiovascular outcome. It is unknown whether anemia has a causal relationship with postoperative adverse cardiac complications or that anemia is a marker of ‘unknown disease’ and that therapeutic interventions,
aimed at decreasing the height of the anemia, do not decrease the risk for adverse events. The current guidelines support a restrictive transfusion strategy and advocate a transfusion trigger of 6.0 mmol/l (9.7 g/dl) for patients at high risk for adverse cardiovascular events. Recent studies have shown that especially patients
at the highest risk for postoperative myocardial ischemia might benefit from a higher transfusion trigger in the perioperative period.

Research aim:
The primary objective of this study is to assess whether
a liberal (6.5 mmol/l) transfusion strategy compared to a restrictive (6.0 mmol/l) transfusion strategy lowers the incidence of major adverse cardiac events (MACE). MACE is defined as a composite endpoint of all-cause mortality, myocardial infarction or unscheduled coronary revascularization up to 30 days after randomization.



Research aim:

Our study focuses on the relationship between anemia and postoperative cardiac ischemia. The main objective of our study is to determine if a causal relationship exists between immediate postoperative hemoglobin levels and the occurrence of postoperative troponin release.



Approach:

The proposed study is a randomized, parallel, two-group multicenter trial. Elective, high-risk non-cardiac
surgery patients will be included if the patients hemoglobin level has fallen below the indicated transfusion
threshold. Patients are randomly allocated to liberal threshold transfusion or restrictive threshold transfusion
strategy. The primary endpoint is the incidence of postoperative troponin release in the first three days after
surgery.

It is unknown whether anemia has a causal relationship with postoperative adverse
cardiac complications or that anemia is a marker of ‘unknown disease’ and that therapeutic interventions, aimed at decreasing the height of the anemia, do not decrease the risk for adverse events. We hypothesize that patients at the highest risk for postoperative myocardial ischemia might benefit from a higher transfusion trigger in the perioperative period.

Preoperative hemoglobin and troponin values will be obtained within 48 hours before surgery. Troponin as well as hemoglobin concentration are measured on postoperative days 1, 2 and 3 (or before discharge).

The primary aim of our study is to compare a liberal (6.5 mmol/l (10.9 g/dl)) transfusion strategy to a restrictive (6.0 mmol/l (9.7 g/dl)) transfusion strategy on postoperative troponin release after non cardiac surgery. The assigned transfusion strategy is followed until the third postoperative day or discharge (whichever comes first).