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Background and Objectives: The practice regarding the selection and preparation of red blood cells (RBCs) for intrauterine transfusion (IUT) is variable reflecting historical practice and expert opinion rather than evidence‐based recommendations. The aim of this survey was to assess Canadian hospital blood bank practice with respect to red cell IUT. Materials and Methods: A survey was sent to nine hospital laboratories known to perform red cell IUT. Questions regarding component selection, processing, foetal pre‐transfusion testing, transfusion administration, documentation and traceability were assessed. Results: The median annual number of IUTs performed in Canada was 109 (interquartile range, 103–118). RBC selection criteria included allogeneic, Cytomegalovirus seronegative, irradiated, fresh units with most sites preferentially providing HbS negative, group O, RhD negative, Kell negative and units lacking the corresponding maternal antibody without extended matching to the maternal phenotype. Red cell processing varied with respect to target haematocrit, use of saline reconstitution (n = 4), use of an automated procedure for red cell concentration (n = 1) and incorporation of a wash step (n = 2). Foetal pre‐transfusion testing uniformly included haemoglobin measurement, but additional serologic testing varied. A variety of strategies were used to link the IUT event to the neonate post‐delivery, including the creation of a unique foetal blood bank identifier at three sites. Conclusion: This survey reviews current practice and highlights the need for standardized national guidelines regarding the selection and preparation of RBCs for IUT. This study has prompted a re‐examination of priorities for RBC selection for IUT and highlighted strategies for transfusion traceability in this unique setting. [ABSTRACT FROM AUTHOR]

Background and Objectives: Platelet transfusions are used across multiple patient populations to prevent and correct bleeding. This scoping review aimed to map the currently available systematic reviews (SRs) and evidence‐based guidelines in the field of platelet transfusion. Materials and Methods: A systematic literature search was conducted in seven databases for SRs on effectiveness (including dose and timing, transfusion trigger and ratio to other blood products), production modalities and decision support related to platelet transfusion. The following data were charted: methodological features of the SR, population, concept and context features, outcomes reported, study design and number of studies included. Results were synthesized in interactive evidence maps. Results: We identified 110 SRs. The majority focused on clinical effectiveness, including prophylactic or therapeutic transfusions compared to no platelet transfusion (34 SRs), prophylactic compared to therapeutic‐only transfusion (8 SRs), dose, timing (11 SRs) and threshold for platelet transfusion (15 SRs) and the ratio of platelet transfusion to other blood products in massive transfusion (14 SRs). Furthermore, we included 34 SRs on decision support, of which 26 evaluated viscoelastic testing. Finally, we identified 22 SRs on platelet production modalities, including derivation (4 SRs), pathogen inactivation (6 SRs), leucodepletion (4 SRs) and ABO/human leucocyte antigen matching (5 SRs). The SRs were mapped according to concept and clinical context. Conclusion: An interactive evidence map of SRs and evidence‐based guidelines in the field of platelet transfusion has been developed and identified multiple reviews. This work serves as a tool for researchers looking for evidence gaps, thereby both supporting research and avoiding unnecessary duplication. [ABSTRACT FROM AUTHOR]

Background and Objectives: Transfusion‐associated circulatory overload (TACO) is the leading cause of transfusion‐related morbidity and mortality. A recently completed pilot trial randomized patients to pre‐transfusion furosemide versus placebo but had a slower than expected enrollment rate. We sought to determine whether the lack of recruitment was due to a paucity of eligible patients or excessively restrictive eligibility criteria. Materials and Methods: At 10 sites, eligible patients were retrospectively identified by first screening blood bank databases over one month for all transfusion episodes meeting trial inclusion criteria, defined as non‐surgical patients receiving single RBC unit transfusions. The age threshold was decreased from 65 to 50 years. The first 10 patients meeting inclusion criteria then underwent detailed chart review for the exclusion criteria. The incidence of TACO and furosemide use was also recorded. Results: At the 10 sites, 11 969 red cell units were transfused over 1 month and 1356 met the inclusion criteria. Of the 100 charts reviewed, 60 (60%) had no exclusion criteria. Active bleeding was the most common reason for ineligibility. There were 813 eligible transfusion episodes. Of the eligible patients, 17 (28·3%) had evidence of congestive heart failure, and furosemide was prescribed in 24 (40%). Despite the use of a lower age threshold, three cases of TACO were detected with an incidence of 3%. Conclusion: A large number of transfusion episodes met eligibility criteria. With a 3% incidence of TACO, 50% decrease through the use pre‐transfusion furosemide and a target consent rate of 30%, a definitive trial of approximately 3000 patients could be completed within 1 year. [ABSTRACT FROM AUTHOR]

Background and Objective Identifying factors that can predict adults at high risk of receiving red blood cell transfusion during coronary artery bypass graft (CABG) surgery may aid in more efficient blood banking practices and may tailor blood conservation strategies for these adult patients. The objective was to identify clinical factors associated with increased red cell transfusion in adults undergoing CABG surgery. Methods A systematic review of the MEDLINE and HealthSTAR databases from 1966 to December 2005 was conducted. Citations containing the medical subject heading or textwords ‘coronary artery bypass graft’, ‘CABG’ and ‘cardiovascular surgery’ were combined with the medical subject headings or textwords ‘transfusion’ and ‘blood transfusion’. Results A total of 2461 abstracts were retrieved. Twenty-one studies met the inclusion/exclusion criteria. Transfusion rates ranged from 7 to 97%. Several variables were identified that were associated with increased red cell transfusion rates including older age, female sex, low haemoglobin concentration or haematocrit value, renal insufficiency and urgent/emergent surgery. The strongest risk factor was the urgency of surgery (urgent or emergent surgery), which was associated with a 4× to 8× increase in transfusion rates compared to elective surgery. Increasing age and female sex increased the likelihood of transfusion by 1× to 3× and 2×, respectively. Conclusions Increasing patient age, female sex, lower preoperative haemoglobin levels, as well as the urgency of the CABG surgery were associated with higher transfusion rates. Identifying risk factors for transfusion may allow for targeted use of blood conservation strategies, improved efficiency in blood utilization and informing adults at risk of transfusion. [ABSTRACT FROM AUTHOR]

Background and Objectives: In Caucasians, fetal/neonatal alloimmune thrombocytopenia (FNAIT) is most commonly due to maternal HPA-1a antibodies. HPA-1a typing followed by screening for anti-HPA-1a antibodies in HPA-1bb women may identify first pregnancies at risk. Our goal was to review results from previous published studies to examine whether the maternal antibody level to HPA-1a could be used to identify high-risk pregnancies., Materials and Methods: The studies included were categorized by recruitment strategies: screening of unselected pregnancies or samples analyzed from known or suspected FNAIT patients., Results: Three prospective studies reported results from screening programmes, and 10 retrospective studies focused on suspected cases of FNAIT. In 8 studies samples for antibody measurement, performed by the monoclonal antibody immobilization of platelet antigen (MAIPA) assay, and samples for determining fetal/neonatal platelet count were collected simultaneously. In these 8 studies, the maternal antibody level correlated with the risk of severe thrombocytopenia. The prospective studies reported high negative predictive values (88-95%), which would allow for the use of maternal anti-HPA-1a antibody level as a predictive tool in a screening setting, in order to identify cases at low risk for FNAIT. However, due to low positive predictive values reported in prospective as well as retrospective studies (54-97%), the maternal antibody level is less suited for the final diagnosis and for guiding antenatal treatment., Conclusion: HPA-1a antibody level has the potential to predict the severity of FNAIT., (© 2018 International Society of Blood Transfusion.)