Red Blood Cell Transfusion: 2023 AABB International Guidelines.

Importance: Red blood cell transfusion is a common medical intervention with benefits and harms. Objective: To provide recommendations for use of red blood cell transfusion in adults and children. Evidence Review: Standards for trustworthy guidelines were followed, including using Grading of Recommendations Assessment, Development and Evaluation methods, managing conflicts of interest, and making values and preferences explicit. Evidence from systematic reviews of randomized controlled trials was reviewed. Findings: For adults, 45 randomized controlled trials with 20 599 participants compared restrictive hemoglobin-based transfusion thresholds, typically 7 to 8 g/dL, with liberal transfusion thresholds of 9 to 10 g/dL. For pediatric patients, 7 randomized controlled trials with 2730 participants compared a variety of restrictive and liberal transfusion thresholds. For most patient populations, results provided moderate quality evidence that restrictive transfusion thresholds did not adversely affect patient-important outcomes. Recommendation 1: for hospitalized adult patients who are hemodynamically stable, the international panel recommends a restrictive transfusion strategy considering transfusion when the hemoglobin concentration is less than 7 g/dL (strong recommendation, moderate certainty evidence). In accordance with the restrictive strategy threshold used in most trials, clinicians may choose a threshold of 7.5 g/dL for patients undergoing cardiac surgery and 8 g/dL for those undergoing orthopedic surgery or those with preexisting cardiovascular disease. Recommendation 2: for hospitalized adult patients with hematologic and oncologic disorders, the panel suggests a restrictive transfusion strategy considering transfusion when the hemoglobin concentration is less than 7 g/dL (conditional recommendations, low certainty evidence). Recommendation 3: for critically ill children and those at risk of critical illness who are hemodynamically stable and without a hemoglobinopathy, cyanotic cardiac condition, or severe hypoxemia, the international panel recommends a restrictive transfusion strategy considering transfusion when the hemoglobin concentration is less than 7 g/dL (strong recommendation, moderate certainty evidence). Recommendation 4: for hemodynamically stable children with congenital heart disease, the international panel suggests a transfusion threshold that is based on the cardiac abnormality and stage of surgical repair: 7 g/dL (biventricular repair), 9 g/dL (single-ventricle palliation), or 7 to 9 g/dL (uncorrected congenital heart disease) (conditional recommendation, low certainty evidence). Conclusions and Relevance: It is good practice to consider overall clinical context and alternative therapies to transfusion when making transfusion decisions about an individual patient.

Patient blood management: recommendations rrom the 2018 Frankfurt consensus conference

What is the current evidence base for patient blood management (PBM) in adults, and what international clinical recommendations can be derived for preoperative anemia, red blood cell transfusion thresholds, and PBM implementation strategies? Diagnosis and management of preoperative anemia is crucial, and iron-deficient anemia should be treated with iron supplementation. Red blood cell transfusion thresholds for critically ill, clinically stable patients (hemoglobin concentration <7 g/dL), patients undergoing cardiac surgery (hemoglobin concentration <7.5 g/dL), patients with hip fractures and cardiovascular disease or risk factors (hemoglobin concentration <8 g/dL), and hemodynamically stable patients with acute gastrointestinal bleeding (hemoglobin concentration 7-8 g/dL) are relatively well defined, although the quality of evidence is moderate to low. Further high-quality research to support PBM is required for a range of clinical scenarios and implementation of PBM programs.

Long-Term Outcomes Among Patients Discharged From the Hospital With Moderate Anemia: A Retrospective Cohort Study.

Background: Randomized clinical trial findings support decreased red blood cell (RBC) transfusion and short-term tolerance of in-hospital anemia. However, long-term outcomes related to changes in transfusion practice have not been described. Objective: To describe the prevalence of anemia at and after hospital discharge and associated morbidity and mortality events. Design: Retrospective cohort study. Setting: Integrated health care delivery system with 21 hospitals serving 4 million members. Participants: 445 371 surviving adults who had 801 261 hospitalizations between January 2010 and December 2014. Measurements: Hemoglobin levels and RBC transfusion, rehospitalization, and mortality events within 6 months of hospital discharge. Generalized estimating equations were used to examine trends over time, accounting for correlated observations and patient-level covariates. Results: From 2010 to 2014, the prevalence of moderate anemia (hemoglobin levels between 7 and 10 g/dL) at hospital discharge increased from 20% to 25% (P < 0.001) and RBC transfusion declined by 28% (39.8 to 28.5 RBC units per 1000 patients; P < 0.001). The proportion of patients whose moderate anemia had resolved within 6 months of hospital discharge decreased from 42% to 34% (P < 0.001), and RBC transfusion and rehospitalization within 6 months of hospital discharge decreased from 19% to 17% and 37% to 33%, respectively (P < 0.001 for both). During this period, the adjusted 6-month mortality rate decreased from 16.1% to 15.6% (P = 0.004) in patients with moderate anemia, in parallel with that of all others. Limitation: Possible unmeasured confounding. Conclusion: Anemia after hospitalization increased in parallel with decreased RBC transfusion. This increase was not accompanied by a rise in subsequent RBC use, rehospitalization, or mortality within 6 months of hospital discharge. Longitudinal analyses support the safety of practice recommendations to limit RBC transfusion and tolerate anemia during and after hospitalization. Primary Funding Source: National Heart, Lung, and Blood Institute.

Clinical Practice Guidelines From the AABB: Red Blood Cell Transfusion Thresholds and Storage.

Importance: More than 100 million units of blood are collected worldwide each year, yet the indication for red blood cell (RBC) transfusion and the optimal length of RBC storage prior to transfusion are uncertain. Objective: To provide recommendations for the target hemoglobin level for RBC transfusion among hospitalized adult patients who are hemodynamically stable and the length of time RBCs should be stored prior to transfusion. Evidence Review: Reference librarians conducted a literature search for randomized clinical trials (RCTs) evaluating hemoglobin thresholds for RBC transfusion (1950-May 2016) and RBC storage duration (1948-May 2016) without language restrictions. The results were summarized using the Grading of Recommendations Assessment, Development and Evaluation method. For RBC transfusion thresholds, 31 RCTs included 12 587 participants and compared restrictive thresholds (transfusion not indicated until the hemoglobin level is 7-8 g/dL) with liberal thresholds (transfusion not indicated until the hemoglobin level is 9-10 g/dL). The summary estimates across trials demonstrated that restrictive RBC transfusion thresholds were not associated with higher rates of adverse clinical outcomes, including 30-day mortality, myocardial infarction, cerebrovascular accident, rebleeding, pneumonia, or thromboembolism. For RBC storage duration, 13 RCTs included 5515 participants randomly allocated to receive fresher blood or standard-issue blood. These RCTs demonstrated that fresher blood did not improve clinical outcomes. Findings: It is good practice to consider the hemoglobin level, the overall clinical context, patient preferences, and alternative therapies when making transfusion decisions regarding an individual patient. Recommendation 1: a restrictive RBC transfusion threshold in which the transfusion is not indicated until the hemoglobin level is 7 g/dL is recommended for hospitalized adult patients who are hemodynamically stable, including critically ill patients, rather than when the hemoglobin level is 10 g/dL (strong recommendation, moderate quality evidence). A restrictive RBC transfusion threshold of 8 g/dL is recommended for patients undergoing orthopedic surgery, cardiac surgery, and those with preexisting cardiovascular disease (strong recommendation, moderate quality evidence). The restrictive transfusion threshold of 7 g/dL is likely comparable with 8 g/dL, but RCT evidence is not available for all patient categories. These recommendations do not apply to patients with acute coronary syndrome, severe thrombocytopenia (patients treated for hematological or oncological reasons who are at risk of bleeding), and chronic transfusion-dependent anemia (not recommended due to insufficient evidence). Recommendation 2: patients, including neonates, should receive RBC units selected at any point within their licensed dating period (standard issue) rather than limiting patients to transfusion of only fresh (storage length: <10 days) RBC units (strong recommendation, moderate quality evidence). Conclusions and Relevance: Research in RBC transfusion medicine has significantly advanced the science in recent years and provides high-quality evidence to inform guidelines. A restrictive transfusion threshold is safe in most clinical settings and the current blood banking practices of using standard-issue blood should be continued.

Evaluation and management of anemia and bleeding disorders in surgical patients.

The perioperative period offers a unique hemostatic and physiologic challenge. Evaluation of anemia and the decision to transfuse play an important role in the perioperative period. Achievement of adequate hemostasis is important. A bleeding-oriented history and physical, along with some baseline tests, may help alert the physician to the possibility of a bleeding disorder. Finally, some patients may need correction of their bleeding disorder before surgery or careful monitoring in the perioperative period.