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.

Single Plasma Unit Transfusions in Adults Are Either Unnecessary or Underdosed.

OBJECTIVES: Previous studies of blood product use have shown higher inappropriate use of plasma compared with other products. Given typical weight-based dosing of plasma, we hypothesized that single plasma transfusions in adults would either be a nontherapeutic dose or outside clinical guidelines. METHODS: A single-center, retrospective review of nonoperative, nonapheresis plasma use was conducted from January 2020 to April 2020. Plasma transfusions were reviewed for compliance with clinical guidelines formulated at our institution as well as national and society guidelines. RESULTS: During the study period, 313 units of plasma were transfused. Of these, 152 (48.6%) were given against institutional or national guidelines, 126 plasma units (40.3%) were transfused as single units, and 187 (59.7%) were given as part of multiple-unit transfusions. All single-unit plasma transfusions during the study period were either underdosed or outside clinical guidelines. Units transfused with an indication of "Other" were significantly more likely to be outside clinical guidelines. CONCLUSIONS: Nonoperative, nonapheresis plasma use is often outside clinical guidelines. Single-unit plasma transfusions in adults are a potential target for patient blood management programs seeking to minimize unnecessary plasma use.

Establishing a Satellite Transfusion Service Within an Academic Medical Center.

OBJECTIVES: Increasingly complex medical care requires specialized transfusion support close at hand. Hospital growth can necessitate expansion of blood bank services to new locations to ensure rapid delivery of blood products. We describe the opening of a new satellite transfusion service designed to serve the needs of a pediatric hospital. METHODS: Institutional transition teams and stakeholders collaborated to discuss options for providing blood at a new pediatric hospital. A staffed satellite transfusion service met the diverse needs of multiple services and was considered a compromise between a full new transfusion service and automated solutions. RESULTS: Initial challenges in establishing the laboratory included regulatory uncertainty and interactions between two hospitals' information technology services. Laboratory scientist staffing and actual use required adapting the satellite service to an emergency release-only model. CONCLUSIONS: A flexibly staffed satellite transfusion service met the most urgent needs of a pediatric hospital expansion. Review of implementation revealed potential process improvements for future expansions, including comprehensive routine and massive transfusion simulations. The challenges experienced in supplying staff and specialized blood products track with national trends. Other institutions may consider establishing a satellite transfusion service in the context of both increasingly sophisticated automated solutions and complex blood needs.

Antiphospholipid Antibodies in Patients With Lupus Anticoagulant Prozone Effect.

OBJECTIVES: Lupus anticoagulant (LAC) is typically associated with thrombosis but also rarely with hemorrhage. Some patients exhibit a prozone effect on LAC testing. Antiphosphatidylserine/prothrombin (aPS/PT) antibodies may provide a mechanism for both hemorrhage and prozone effect. Our goal was to evaluate whether antibody specificities, isotypes, and titers were associated with LAC prozone effect, factor II levels, hemorrhage, and thrombosis. METHODS: Patients with prozone effect noted on LAC testing were entered into a database over 3 years. Factor II activity and aPS/PT antibody testing were performed when a sufficient residual sample was available. RESULTS: All patients with LAC prozone effect and antibody testing were positive for at least 1 class of aPS/PT antibodies. In addition, aPS/PT IgG titers were significantly associated with thrombosis and significantly inversely associated with factor II levels. CONCLUSIONS: In prozone effect patients, aPS/PT antibodies are associated with LAC prozone effect as well as thrombosis and decreased factor II levels.

Comparison of Phenotypic Activated Protein C Resistance Testing With a Genetic Assay for Factor V Leiden.

Objectives: To compare the accuracy and reliability of phenotypic activated protein C resistance (aPC-R) assays with a genotypic assay for the factor V Leiden F5 p.R506Q (FVL) mutation. Methods: Data were obtained from an electronic data warehouse for FVL testing performed at an academic institution with a large referral laboratory service. In total, 1,596 patients were identified who had undergone both phenotypic aPC-R and genotypic FVL mutation testing. Results: Phenotypic testing showed a high level of sensitivity, specificity, and other biostatistical values compared with genotypic testing. Improvements in technology decreased the amount of equivocal phenotypic results. Conclusions: Phenotypic assays had close to total concordance with genotypic assays over 16 years of testing. Changing ordering practices could result in up to an 80% reduction in testing costs.

Massive transfusion: red blood cell to plasma and platelet unit ratios for resuscitation of massive hemorrhage.

PURPOSE OF REVIEW: The aim of this short study is to review recently published data bearing on how to resuscitate massive uncontrolled hemorrhage. RECENT FINDINGS: New data inform our understanding of the mechanisms of the acute coagulopathy of trauma, the median time to death of trauma patients with uncontrolled hemorrhage, the effects of blood product composition on the coagulation capacity of infused resuscitation mixtures, the outcomes of patients resuscitated according to common massive transfusion protocols in clinical situations associated with massive hemorrhage, and who might benefit from balanced, blood-product-based resuscitation. Importantly, the trial methods, blood bank methods, and primary outcomes of the Pragmatic Randomized Optimal Plasma and Platelet Ratios (PROPPR) trial were recently published. Resuscitation with a 1 : 1 : 1 ratio of units of plasma and platelets to red blood cells was well tolerated and reduced hemorrhagic mortality during resuscitation in the PROPPR trial. SUMMARY: The bulk of currently available data support the use of a 1 : 1 : 1 ratio for the resuscitation of patients with severe injury, shock, and uncontrolled hemorrhage. The application of this formulaic approach to massive blood product-based resuscitation in other clinical situations is less well supported in the literature.