Unlike its previous 2012 guidelines that recommended overlapping hemoglobin level triggers of 7 g/dL to 8 g/dL for most inpatients, the 2016 guidelines from AABB (formerly known as the American Association of Blood Banks) assigns 2 distinct tiers of hemoglobin transfusion triggers: 7 g/DL for hemodynamically stable adults, including those in intensive care units, and 8 g/dL for patients undergoing cardiac or orthopedic surgery or with preexisting cardiovascular disease1 , often defined as history of coronary artery disease, angina, myocardial infarction, stroke, congestive heart failure, or peripheral vascular disease2,3.
These recommendations are based on an analysis of over 30 randomized trials, taking into account the potential risks of withholding transfusions, including 30-day mortality, and myocardial infarction. The new 2-tier recommendation specifically excludes those with acute coronary syndrome, severe thrombocytopenia (patients treated for hematological or oncological reasons who are at risk of bleeding), and chronic transfusion-dependent anemia.
The guidelines also emphasize that good clinical practice dictates considering not only the hemoglobin level but the overall clinical context when considering blood transfusion in patients. These factors include alternative therapies to transfusion, rate of decline in hemoglobin level, intravascular volume status, dyspnea, exercise tolerance, light-headedness, chest pain considered of cardiac origin, hypotension, tachycardia unresponsive to fluid challenge, and patient preferences. In addition, standard practice should be to initiate a transfusion with 1 unit of blood rather than 2 units1.
- Carson JL, Guyatt G, Heddle NW. Clinical practice guidelines from the AABB red blood cell transfusion thresholds and storage. JAMA. Doi:10.1001/jama.2016.9185. Published online October 12, 2016.
- Carson JL, Duff A, Poses RM, et al. Effect of anemia and cardiovascular disease on surgical mortality and morbidity. Lancet 1996;348:1055-60.
- Carson JL, Siever F, Cook DR, et al. Liberal versus restrictive blood transfusion strategy: 3-year survial and cause of death results from the FOCUS randomized controlled trial. Lancet 2015;385:1183-1189.