We’ve done several columns highlighting some of the detrimental effects related to red blood cell transfusions (see our What’s New in the Patient Safety World columns for March 2011 “Downside of Transfusions in Surgery”, February 2012 “February 2012 More Bad News on Transfusions”, and January 2012 “Need for New Transfusion Criteria?”).
Add to that a paper just presented at the Annual Meeting of the Society of Thoracic Surgeons (Horvath 2012). They found that transfusions were associated with a significant risk of infection in cardiac procedures. And while there seemed to be a threshold in the 2-4 unit range above which the risk really seemed to increase, there was an additional infection risk even with the first unit of blood transfused. A variety of infections were associated with these transfusions in a dose-dependent manner. The crude risk of infection increased an average 29% with each unit of packed RBC’s transfused.
And as we implied in our January 2012 What’s New in the Patient Safety World column “Need for New Transfusion Criteria?”, the AABB (formerly the American Association of Blood Banks) has just come out with new clinical guidelines for red blood cell transfusion (Carson 2012). The main recommendation is adhering to a restrictive transfusion strategy (7 to 8 g/dL threshold) in hospitalized, stable patients (Grade: strong recommendation; high-quality evidence). They also recommend adhering to a restrictive strategy in hospitalized patients with preexisting cardiovascular disease and considering transfusion for patients with symptoms or a hemoglobin level of 8 g/dL or less (Grade: weak recommendation; moderate-quality evidence). They could not recommend for or against a liberal or restrictive transfusion threshold for hospitalized, hemodynamically stable patients with the acute coronary syndrome. Lastly, they suggest that transfusion decisions be influenced by symptoms as well as hemoglobin concentration, as most previous guidelines have recommended.
Undoubtedly these new guidelines will kindle some debate, as highlighted in the editorial accompanying the guideline publication (Vincent 2012). His argument centers around the need to balance the risks and benefits of transfusion against the risks and benefits associated with anemia management.
The debate may continue but the new AABB guidelines set a new standard and emphasize the need to carefully weigh both the potential benefits and risks each time you are faced with a decision about whether to transfuse or not.
Horvath KA et al. Do Blood Transfusions Affect the Risk of Infections After Cardiac Surgery? Experience of the NIH/CIHR Cardiothoracic Surgical Trials Network. Abstract presented at the 2012 Annual Meeting of the Society of Thoracic Surgeons as summarized in Wachter K. Cardiac Surgical Transfusions Linked to Infection Risk. Hospitalist News Digital Network. March 15, 2012
Carson JL, Grossman BJ, Kleinman S, et al. for the Clinical Transfusion Medicine Committee of the AABB. Clinical Guidelines.Red Blood Cell Transfusion: A Clinical Practice Guideline From the AABB. Ann Intern Med 2012; E-429 published ahead of print March 26, 2012
Vincent J-L. Editorial. Indications for Blood Transfusions: Too Complex to Base on a Single Number? Ann Intern Med 2012; published ahead of print March 26, 2012