Blood Transfusion in Heart Surgery Increases Infection Risk

Patients had a mean age of 64 ± 13 years and preoperative hemoglobin of 13 ± 1.8 g/dL; 33% were women and 19% had undergone prior cardiac surgery.

Among the patients in the study, RBCs were transfused in 2,481 (48%), and platelets were transfused in 1,599 (31%). The highest volume of RBCs was given during transplant or left ventricular assist device implantation (84%) and thoracic aortic procedures (63%), while the lowest volumes were given for isolated coronary artery bypass grafting surgery (45%) and isolated valve surgery (40%).

Within 65 days following surgery, 235 patients (5%) were diagnosed with one or more major infections, the most common being pneumonia, Clostridium difficile colitis, a bacterial infection in the colon, and bloodstream infections. The authors found a dose-related association between the quantity of RBCs transfused and the unadjusted risk of infection, with a 29% increase in infection with each RBC unit transfused. Conversely, a lower risk of infection was observed when platelets were also transfused in conjunction with more than four units of RBCs.

Keith A. Horvath, MD, the senior author of the study, said, “A common problem for many surgeons, and thereby the patient, is how to balance the risk of surgery-induced anemia with the increased risk of infection when using red blood cell transfusion to correct the anemia. Through this study we hoped to shed light on the problem and to encourage hospitals and surgeons to examine cell-salvage techniques and other alternatives to RBC transfusion during and after cardiac surgery.” The study was published in the June 2013 edition of the Annals of Thoracic Surgery.

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US National Institutes of Health

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