Blood Transfusion and Survival in Cardiac Surgery

not included in the model, yet there was a disproportionate number of subjects who died with a cancer-related diagnosis in the group not receiving transfusion compared with the transfused groups (P 0.03). If subjects who died from a cancer-related diagnosis are excluded from the analysis, mortality data from the three transfusion groups pooled, and the cumulative mortality rate recalculated to compare patients who received any transfusion with those who were not transfused, the mortality rate for transfused patients is more than twice that of patients who were not transfused (13.2% vs. 6.0%). This is a striking finding consistent with previous studies. What should we tell our patients and how should we approach the transfusion decision in the setting of cardiothoracic surgery? First, as we demonstrated, the data presented in this study do not provide reassurance that patients who receive perioperative transfusion are unlikely to experience a reduction in long-term survival; this remains an open question, with current evidence favoring a restrictive transfusion strategy being associated with lower mortality. At a minimum, there seems to be no benefit to transfusion in the majority of patients. Transfusion is associated with substantial cost and a host of well-documented risks, including disease transmission, hemolytic reactions, acute lung injury, and circulatory overload. Therefore, strategies to optimize hemoglobin and minimize bleeding and transfusion should be used. Transfusion rates of greater than 50% in uncomplicated coronary artery bypass procedures should no longer be tolerated. A number of programs have demonstrated the ability to perform coronary artery bypass surgery with transfusion rates consistently less than 20%. Transfusion in cardiac surgery should be an uncommon event. More data are needed, but until then, the decision to transfuse should continue to be viewed as one that carries substantial risk but no proven benefit in the hemodynamically stable patient.