Summary

The 2023 AABB international guideline updates RBC transfusion recommendations for hospitalized adults and children based on 45 adult RCTs (n=20,599) and 7 pediatric RCTs (n=2,730). For hemodynamically stable patients, restrictive thresholds (typically Hgb <7 g/dL) are non-inferior to liberal thresholds (9–10 g/dL) for mortality and major morbidity. New since 2016: explicit pediatric recommendations, including separate thresholds by cardiac repair stage in congenital heart disease, and extension of restrictive strategy to hematology/oncology inpatients.

Key Recommendations

Use a restrictive transfusion strategy with Hgb <7 g/dL trigger in hospitalized, hemodynamically stable adults (strong recommendation).
In hematology/oncology inpatients, transfuse at Hgb <7 g/dL (conditional recommendation).
In cardiac surgery patients, a Hgb threshold of 7.5 g/dL is acceptable.
In orthopedic surgery patients or those with preexisting cardiovascular disease, a Hgb threshold of 8 g/dL is acceptable.
No recommendation for or against restrictive vs liberal transfusion in acute myocardial infarction (await MINT trial).
In critically ill or at-risk hospitalized children who are hemodynamically stable (without hemoglobinopathy, cyanotic heart disease, or severe hypoxemia), transfuse at Hgb <7 g/dL (strong recommendation).
In children with biventricular congenital heart repair, use Hgb threshold of 7 g/dL.
In children with single-ventricle palliation, use Hgb threshold of 9 g/dL.
In children with uncorrected congenital heart disease, use Hgb threshold of 7–9 g/dL.
Integrate symptoms, signs, comorbidities, bleeding rate, and patient preferences with Hgb value; do not transfuse on Hgb alone.
Storage age of RBCs need not be considered in transfusion decisions.
Guideline does not apply to chronic transfusion-dependent patients (e.g., hemoglobinopathies, MDS) or preterm neonates.

Thresholds & Doses

Adults, hemodynamically stable: transfuse at Hgb <7 g/dL.
Adult cardiac surgery: transfuse at Hgb <7.5 g/dL.
Adult orthopedic surgery or preexisting CV disease: transfuse at Hgb <8 g/dL.
Adult hematology/oncology inpatients: transfuse at Hgb <7 g/dL.
Liberal comparator threshold in trials: typically Hgb 9–10 g/dL.
Pediatric critically ill, hemodynamically stable: transfuse at Hgb <7 g/dL (vs <9.5 g/dL liberal).
Pediatric biventricular CHD repair: Hgb threshold 7 g/dL.
Pediatric single-ventricle palliation: Hgb threshold 9 g/dL.
Pediatric uncorrected CHD: Hgb threshold 7–9 g/dL.
Restrictive strategy reduced transfusion exposure by 32.4% absolute (RR 0.60, 95% CI 0.54–0.66) in adults.
30-day mortality with restrictive vs liberal in adults: RR 1.00 (95% CI 0.86–1.16); baseline 8.3%.
Per-unit RBC risks: TACO 1:125; febrile reaction 1:161; allergic reaction 1:345; TRALI 1:1250; anaphylaxis 1:5000; HBV 1:100,000; HCV 1:200,000; HIV 1:600,000.

Citations

Recommendation 1 — restrictive Hgb <7 g/dL threshold for hemodynamically stable adults, with 7.5 g/dL cardiac surgery and 8 g/dL orthopedic/CVD subgroups.
Recommendation 2 — Hgb <7 g/dL threshold in hematology/oncology inpatients.
Recommendation 3 — Hgb <7 g/dL in critically ill, hemodynamically stable children without hemoglobinopathy, cyanotic heart disease, or severe hypoxemia.
Recommendation 4 — congenital heart disease pediatric thresholds (7, 9, 7–9 g/dL).
Table 1 — per-unit RBC transfusion risks in the US.
Table 2 — adult summary of findings for mortality, MI, CHF, CVA, infection, thromboembolism, transfusion exposure.
Table 4 — pediatric summary of findings for transfusion exposure, 30-day mortality, pneumonia, thrombosis.
Good Practice Statement — integrate symptoms, signs, labs, volume status, patient preferences beyond Hgb alone.