Intraoperative red blood transfusion is associated with adverse outcome after cardiac surgery

Introduction

Bleeding occurs in about 20% of cardiac surgery and is associated with significant morbidity. In this context, red cell transfusions are used to augment the delivery of oxygen to avoid the deleterious effect of oxygen debt. However, blood cell transfusions are associated with morbidity and mortality in clinical studies with critically ill patients. The purpose of this study was to evaluate the relationship between blood transfusion in the operative room and clinical outcomes after cardiac surgery.

Methods

We performed a consecutive observational study in a university hospital. A total of 125 patients undergoing elective coronary artery bypass graft surgery or valve surgery were studied. Demographic data were analyzed. Postoperative cardiac dysfunction was defined as low cardiac output or hemodynamic instability requiring inotropic support for >24 hours. Renal dysfunction was defined as >50% increase in serum creatinine from baseline. Univariate and multivariate analyses were performed.

Results

Of 125 patients, 41 (32.8%) received blood transfusion in the intraoperative room. Patients who received blood transfusion had more postoperative complications than those who did not (P < 0.001). Intraoperative blood transfusion was a risk factor for low-output syndrome (P = 0.02), renal dysfunction (P < 0.003), infection (P < 0.008) and longer stay in the ICU (P = 0.01). In a multivariate analysis, blood cell transfusion increased independently the risk of renal dysfunction (OR = 5.5, 95% CI = 1.5–16.9).

Conclusion

In this observational study, intraoperative blood cell transfusion predicted the outcome after cardiac surgery, resulting in more postoperative complications. These findings suggest that the criteria for perioperative blood transfusion should be revised, considering potential risks.