Red blood cell (RBC) transfusion is a common treatment used to restore tissue oxygenation when oxygen demand exceeds supply.¹ As RBC transfusion is a costly treatment that carries the risk for both infectious and non-infectious complications, clinicians must balance between the benefits of maintaining oxygen delivery and the potential harm.^2,3 Given the increasing number of randomized controlled trials (RCTs) assessing outcomes of different transfusion thresholds as well as the absence of preexisting RBC transfusion guidelines specific to children, the Association for the Advancement of Blood & Biotherapies (AABB) recently published the updated 2023 AABB guidelines for RBC transfusions.³

RBC transfusions are most often administered to surgical and intensive care patients, as well as patients with chronic anemia.^1,2 However, transfusion therapy has been identified as one of the most frequently overused therapeutic interventions which may increase the challenge of maintaining adequate RBC stocks.^2,3 Moreover, potential risks of RBC transfusions include febrile and allergic reactions, transfusion-associated circulatory overload, and the transmission of pathogens for infectious diseases such as hepatitis B/C virus and HIV.^2,3 To address these issues, the updated 2023 AABB guidelines aim to provide recommendations for RBC transfusions in adults and children, emphasizing minimizing complications.³

These guidelines possessed 2 objectives.³ Firstly, to address whether clinicians should transfuse with a restrictive (typical hemoglobin level <7-8g/dL) vs. a liberal strategy (hemoglobin level <9-10g/dL) for hospitalized, hemodynamically stable adult patients.³ Secondly, to address whether clinicians should transfuse hospitalized, hemodynamically stable pediatric patients with or without congenital heart disease with a restrictive (hemoglobin level <7-8g/dL) vs. a liberal strategy (hemoglobin level <9-10g/dL). In total, evidence from 45 RCTs with 20,599 adult participants and 7 RCTs, which consisted of transfusion groups assigned based on clear transfusion thresholds, with 2,730 pediatric participants were reviewed.³

Based on the 45 RCTs with adult participants, the international panel recommends a restrictive transfusion strategy that considers transfusion when the hemoglobin concentration is <7g/dL for hospitalized adult patients who are hemodynamically stable (strong recommendation, moderate certainty evidence).³ However, clinicians may adjust the threshold to 7.5g/dL for patients undergoing cardiac surgery and to 8g/dL for patients undergoing orthopedic surgery or those with preexisting cardiovascular disease.³ Additionally, for hospitalized adult patients with hematologic and oncologic disorders, the panel suggests a restrictive transfusion strategy that initiates transfusion when the hemoglobin concentration is <7g/dL (conditional recommendations, low certainty evidence).³

For critically ill children and hospitalized children at risk of critical illness who are hemodynamically stable and without a transfusion-dependent hemoglobinopathy, cyanotic cardiac condition, or severe hypoxemia, the international panel recommends a restrictive transfusion strategy in which a transfusion is considered when the hemoglobin level is <7g/dL compared with <9.5g/dL (strong recommendation, moderate certainty evidence).³ Furthermore, for hemodynamically stable children with congenital heart disease, the international panel suggests a transfusion threshold based on the cardiac abnormality and stage of surgical repair: 7g/dL (biventricular repair), 9g/dL (single-ventricle palliation), or 7-9g/dL (uncorrected congenital heart disease) (conditional recommendation, low certainty evidence).³

In summary, similar to older guidelines, this guideline continues to recommend restrictive transfusion strategies which would help avoid the adverse effects after RBC transfusion and conserve resources to ensure blood is available for those who need it most.³ Good transfusion practice, however, should not rely solely on hemoglobin concentration thresholds, but incorporate patients’ symptoms, signs, comorbidities, rate of bleeding, values, and preferences.³