Updated AABB guidelines offer hemoglobin thresholds for transfusion

The Association for the Advancement of Blood and Biotherapies (AABB) released updated international guidelines advising clinicians on when they should consider red blood cell transfusion for patients.

In addition to outlining transfusion thresholds for different sets of patients, the guidelines highlight the importance of taking both clinical context and alternative therapies to transfusion into consideration. The guidelines for adult patients were based on assessment of 45 randomized controlled trials, with a total of 20,599 participants, comparing a range of restrictive and liberal hemoglobin-based transfusion thresholds. The updated guidelines were published by JAMA on Oct. 12.

For hemodynamically stable hospitalized adult patients, the AABB panel recommends a restrictive strategy, considering transfusion for those with hemoglobin concentrations below 7 g/dL (strong recommendation, moderate-certainty evidence). However, based on the evidence, clinicians could choose thresholds of 8 g/dL in adults who have pre-existing cardiovascular disease or who are undergoing orthopedic surgery and 7.5 g/dL in those who are undergoing cardiac surgery.

The second recommendation, which concerns hospitalized adults with hematologic or oncologic disorders, outlines a similar restrictive strategy, suggesting clinicians consider transfusion at the threshold of 7 g/dL (conditional recommendation, low-certainty evidence). The guidelines also offer transfusion thresholds for pediatric patients, categorized by their specific conditions.

The guideline authors cautioned that transfusion decisions should “rely not only on hemoglobin concentration thresholds but also incorporation of patients' symptoms, signs, comorbid conditions, rate of bleeding, values, and preferences.” They also noted that strategies such as blood management programs will be required for implementation of the guidelines.

An accompanying Viewpoint focused on the importance of blood management, noting that research has not definitely determined when transfusion may be indicated for any given patient “or whether transfusion strategies incorporating patient clinical features, patient-specific physiological responses, and/or markers of tissue oxygenation may improve transfusion decisions and clinical outcomes.” The authors also argued it is “time to look beyond transfusion as the fundamental driver of blood health optimization” and focus efforts on preserving patients' own blood.