Abstract 16445: The Impact of Peri-Operative Blood Transfusion in Patients Undergoing Isolated Coronary Artery Bypass Grafting Surgery
Background: The practice of blood transfusion in patients undergoing CABG is highly variable and is largely based on the clinicians' clinical judgment rather than official guidelines. This prospective study was designed to assess the potential impact of admission and discharge hemoglobin levels as well as blood transfusions on short and long-term mortality following CABG.
Methods: Patients having isolated CABG surgery (N=2882) were examined for admission and discharge hemoglobin levels and were categorized based on timing of transfusion: none, intra-operative, post-operative or both. Logistic regressions were conducted to evaluate the relationship of hemoglobin level and blood transfusion to operative and long-term mortality after adjustment for clinical variables. Cox proportional hazard regression analyses were also conducted to assess the effect of transfusion on follow-up survival.
Results: Higher admission hemoglobin levels were significantly predictive of reduced long-term mortality (OR=0.89, p=0.01), but not operative mortality (OR=0.89, p=0.25). Patients who received intra-operative blood products had greater risk for operative mortality (OR=4.73, p<0.001) while those receiving blood products both intra-operatively and postoperatively had almost nine times higher risk for operative mortality (OR=8.87, p<0.001). Transfusion groups also predicted long-term survival, such that intraoperative (HR=2.32, p<0.001), postoperative (HR=1.75, p=0.003), and transfusion at both time points (HR=2.03, p=0.006) had reduced survival as compared to the group with no blood products. In patients with very low and low admission hemoglobin, discharge hemoglobin levels did not effect 30-day mortality (OR=0.98, p=0.93), but higher discharge hemoglobin level, as a result of blood transfusions, was associated with significantly greater odds of long-term mortality (OR=1.24, p=0.01).
Conclusions: Transfusion of blood products increased the risk of operative and long-term mortality, with a cumulative effect of more transfusions. Given these results, efforts should be made to employ blood conservation techniques and reduce transfusion for correction of asymptomatic anemia.
- © 2011 by American Heart Association, Inc.