Practice Of Transfusion Medicine Research Articles

Haemoglobin phenotypes and the risk of asymptomatic malaria parasitemia among blood donors in northwest Nigeria: clinical implications in the practice of tropical transfusion medicine

Background: In malaria-endemic populations, sickle cell trait (SCT) protects against both severe and non-severe malaria, but inconsistencies exist about protective effect of SCT on asymptomatic malarial parasitemia (AMP). Surprisingly, the effect of Hb-phenotypes on AMP has not been explored among blood donors in Nigeria or other malaria-endemic countries, where risks of AMP and transfusion transmitted malaria (TTM) are high. The objective of this study is to determine risk of AMP with respect to donor Hb-phenotypes (SCT versus HbAA), and elucidate clinical implications of AMP with respect to risk of TTM vis-à-vis the practice of transfusion medicine in Nigeria, and by implication other malaria-endemic tropical countries.Methodology: Analysis of 100 blood donors with AMP (cases) and 100 donors without AMP (controls) was performed. Frequencies of SCT and HbAA (determined by Hb electrophoresis) among cases and controls were compared by X2 -test. Risks of AMP (detected by microscopy) with respect to Hb-phenotypes were expressed as Odds ratios (OR) by case-control logistic regression.Results: In comparison with blood donor without AMP (controls), donors with AMP had lower frequencies of SCT (12% vs 28%, p<0.05) with corresponding higher frequencies of HbAA (88% vs 72%, p<0.05). HbAA is associated with high risk of AMP (OR=2.91, 95%CI: 2.10-3.48, p=0.021), while SCT is associated low risk of AMP (OR=0.49, 95%CI: 0.27-0.73, p=0.032).Conclusion: This finding shows that donor SCT is a surreptitious mitigator of the risk of AMP and TTM in the tropics. Therefore, patients who are selectively transfused with HbAA blood (e. g. neonates and sickle cell disease patients) could be at greater risks of TTM, and such patients need closer post transfusion monitoring. The risk of TTM calls for diligent post transfusion haemovigilance in Nigeria and other malaria endemic tropical countries in Africa
 Keywords: blood donors, sickle cell trait, asymptomatic malaria parasitemia, transfusion transmitted malaria

Distribution of Kell antigens K, k, Kpa, and Kpb among blood donors in Jeddah city of Western Saudi Arabia.

CONTEXT:Kell blood group system is considered as the third clinically significant blood group in blood transfusion due to the highly immunogenetic of their antigens. No data are available regarding the frequencies of the Kell blood group antigens in Jeddah city. Knowledge of the antigen and phenotype frequencies is crucial to assess the risk of alloimmunization and to guide the probability of finding antigen-negative donor blood, which can be useful when blood transfusion is required for a patient who has multiple red cell alloantibodies.AIMS:The aim of this study was to determine the distribution of Kell blood group: K, k, Kpa, and Kpb antigens and phenotypes among blood donors in Jeddah city, western Saudi Arabia, to improve the transfusion services in the area.SUBJECTS AND METHODS:Seven hundred and fifty-eight blood samples from blood donors were used in the study. The samples were collected from different national blood bank centers in Jeddah city hospitals. Kell antigens were typed through gel card method using commercial antisera.STATISTICAL ANALYSIS USED:The gathered data were analyzed using the SPSS program. Frequency and crosstab tests were completed to achieve the objectives of the current study.RESULTS:The most frequent Kell phenotype in this study was Kp(a−b+), followed by K−k+, K+k+, and then Kp(a+b+), and the less frequent was K+k−. K−k− and Kp(a+b−) phenotypes were not observed in studied donors.CONCLUSIONS:This study is the first report to determine the frequency of Kell antigens and phenotypes among blood donors in Jeddah city. These results appear to be useful in providing better care for patients by implementing tests that should become a routine in blood banks. The Kell system is very important in transfusion medicine practice.

Antalya Eğitim ve Araştırma Hastanesi Transfüzyon Merkezi’ne başvuran donörlerde ABO ve Rhesus (Rh) kan grupları dağılımının araştırılması

Amaç: Bölgemizdeki ABO ve Rhesus (Rh) kan grubu dağılımını belirleyerek transfüzyon tıbbı uygulamalarımıza ve ülkemizin kan grubu veri tabanına katkı sağlamayı amaçladık. Yöntem: Antalya Eğitim ve Araştırma Hastanesi Transfüzyon Merkezi’ne 01.01.2013 ile 01.09.2019 tarihleri arasında başvuran donörlerin ABO ve Rh kan grubu bilgileri retrospektif olarak analiz edildi. Birden fazla bağışta bulunan donörlerin tek kan grubu verisi dahil edildi. Kan grupları kolon aglutinasyon yöntemi ile saptandı. Bulgular: Başvurusu kabul edilen 15.997 donörden 10.867 donörün kan grubu çalışmaya alındı. Donörler 10.335 (% 95.10) erkek ve 532 (% 4.90) kadından oluşmakta ve yaş aralığı 37.38 ± 9.52 idi. Çalışmanın sonuçlarına göre 4.676 (% 43.0) kişi A kan grubu, 3.750 (% 34.9) kişi O kan grubu, 1.695 (%15.6) kişi B kan grubu, 706 (% 6.5) kişi AB kan grubu olarak saptanırken, 9.830 kişi (% 90.5) Rh (+) ve 1.037 kişi (% 9.5) Rh (-) olarak saptandı. Sonuç: Çalışmamızın sonuçları ülkemizin ABO ve Rh kan grubu dağılımı ile uyum göstermiştir. Ülkemiz genelinde olduğu gibi A kan grubu oranı en yüksek iken onu 0, B ve AB kan grupları izlemiştir. Antalya bölgesinde ilk kez yapılan çalışmamızın sonuçlarının transfüzyon tıbbı uygulamalarımıza, ülkemizin kan grupları dağılımı veri tabanına ve bilimsel çalışmalara katkı sağlayacağı düşünülmektedir.

Prospective audit of blood transfusion request forms and continuing medical education to optimise compliance of clinicians in a hospital setting.

The aim of this study was to analyse blood requisition forms sent by clinicians in a tertiary care hospital to the transfusion service to ascertain their completeness and correctness. A secondary objective was to study the effect of continuing medical education (CME) in a hospital setting on clinician's behaviour regarding the importance of details that ought to be mentioned on blood requisition forms. Transfusion audits are useful tools in the evaluation and education of those requesting blood components. This was a prospective, observational study conducted in the department of Transfusion Medicine at a tertiary-level healthcare centre from June 2019 to December 2019. The study was divided into two phases: pre-CME (P1) and post-CME (P2). In both phases, an audit for assessing completeness and correctness of blood requisition forms, which were divided into four sections, was performed. A scoring system was devised to compare both phases. In the P1 phase, 45.77% of the blood requisition form entries were complete and correct; 23.45% of incomplete entries were generated by emergency and trauma. In the P2 phase, 76.75% of the blood requisition form entries were complete and correct; 35.09% of the incomplete entries were generated by obstetrics and gynaecology. Complete and correct entries increased from 45.7% (P1) to 76.75% (P2). Scores of P1 were found to be lower than scores of P2 for all four sections. Cumulative mean score for P1 (20687) was found to be significantly lower than the mean score for P2 (30870). Audit and CME regarding different aspects of transfusion medicine practices play a major role in the improvement of transfusion practices in hospitals.

Transfusion Medicine Practice During COVID-19 Pandemic: Potential Pitfalls and Solutions for Provision of Blood Products

Transfusion Medicine Practice During COVID-19 Pandemic: Potential Pitfalls and Solutions for Provision of Blood Products

Medical student education in transfusion medicine, part II: Moving forward to building up a "Know How" education program in transfusion medicine for under-graduate medical students

There is a general trend in changing paradigm in teaching medicine; the emerging concept relies on a competence-based approach. Transfusion is either a discipline or a subsidiary of others depending on the countries and systems; this variability can be explained because transfusion is a medical care that is transdisciplinary. As a collective of professionals in both transfusion medicine practice and education, authors aim to propose a revision of the way education in transfusion medicine is delivered in this era of the ‘global competency approach’. They advocate in favor of a Know How on 5 key issues: Diagnosing the patient condition in line with the Patient Blood Management principles; Facing acute blood loss; Addressing compatibility and avoiding immunization; Seeking for maximized benefits and dampening complications; and Inlaying competence within global health care issues, also comprising od economy. The methods used would be those developed for medical education at large, such as assessment tools. The global objective is to deliver the necessary competence to manage patients by an intern/resident. At the end of the curriculum, students should be able to self-evaluate the following items: 1) Do I know why my patient is anemic, thrombocytopenic, bleeding….? 2) Do I know the best approach to treat anemia, thrombocytopenia, bleeding (including the “no treatment” option)? 3) Do I know whether a transfusion approach is appropriate for my patients? 4) Do I know how to evaluate and anticipate benefits from blood transfusion and to avoid side-effects in the patient? 5) Do I know how to avoid unnecessary use of the products?

Transfusion Medicine Practice in a Pandemic; Use of Convalescent Plasma in the Management of COVID-19

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Patient Blood Management in Adult Extracorporeal Membrane Oxygenation Patients

This narrative review provides a framework for contemporary patient blood management (PBM) in adult extracorporeal membrane oxygenation (ECMO) patients. ECMO use is growing in adults with cardiopulmonary failure and bleeding, and allogeneic transfusion is common. There are no high quality randomized controlled trials to guide transfusion strategies or anticoagulation. Recent studies offer some insight into the coagulation changes that occur during ECMO, optimal anticoagulation practices, and potential therapies for bleeding. PBM for adult ECMO patients should be grounded in an understanding of the coagulation changes that occur during ECMO and evidence-based transfusion medicine practices. As randomized controlled trials are completed, PBM will continue to mature, which should help to improve outcomes and reduce costs for ECMO patients.

Transfusion Medicine Equations Made Internet Accessible.

Multiple mathematical equations inform the practice of transfusion medicine. These equations apply to a wide range of topics: dosage of blood products, calculation of fluid volumes, and even specific treatment decisions (e.g. corrected count increment for determination of platelet refractoriness). The calculation of these equations can be complicated, prone to error, and time-consuming. A trusted source is needed to accurately perform these calculations 24 hours a day without error and without monetary cost. We sought to build internet-enabled calculators relevant to the practice of transfusion medicine. We partnered with MDCalc, an online host of medical calculators with 1 million monthly users in 196 countries, to design and host the calculators. The calculators guide users in the application of transfusion medicine equations by providing indications for use, inputs for the equations variables, error-checking, warnings for bad inputs, and interpretive guidance of the result. The following calculators were built: blood volume, corrected count increment (CCI), plasma dosage, cryoprecipitated antihemophilic factor dosage, approximate number of units for compatibility testing, maternal-fetal hemorrhage Rh(D) immune globulin dosage, intrauterine RBC transfusion dosage, neonatal polycythemia partial exchange, theoretical removal of a substance by plasmapheresis, sickle cell RBC exchange volume, peripheral blood stem cell collection, and a calculator relevant to donor lymphocyte infusion. Clinicians can now utilize this reputable and highly visible online source to access these common transfusion medicine equations at any time with an internet-enabled device (https://www.mdcalc.com/search?filter=transfusion+medicine).

Automated typing of red blood cell and platelet antigens: a whole-genome sequencing study

There are more than 300 known red blood cell (RBC) antigens and 33 platelet antigens that differ between individuals. Sensitisation to antigens is a serious complication that can occur in prenatal medicine and after blood transfusion, particularly for patients who require multiple transfusions. Although pre-transfusion compatibility testing largely relies on serological methods, reagents are not available for many antigens. Methods based on single-nucleotide polymorphism (SNP) arrays have been used, but typing for ABO and Rh-the most important blood groups-cannot be done with SNP typing alone. We aimed to develop a novel method based on whole-genome sequencing to identify RBC and platelet antigens. This whole-genome sequencing study is a subanalysis of data from patients in the whole-genome sequencing arm of the MedSeq Project randomised controlled trial (NCT01736566) with no measured patient outcomes. We created a database of molecular changes in RBC and platelet antigens and developed an automated antigen-typing algorithm based on whole-genome sequencing (bloodTyper). This algorithm was iteratively improved to address cis-trans haplotype ambiguities and homologous gene alignments. Whole-genome sequencing data from 110 MedSeq participants (30 × depth) were used to initially validate bloodTyper through comparison with conventional serology and SNP methods for typing of 38 RBC antigens in 12 blood-group systems and 22 human platelet antigens. bloodTyper was further validated with whole-genome sequencing data from 200 INTERVAL trial participants (15 × depth) with serological comparisons. We iteratively improved bloodTyper by comparing its typing results with conventional serological and SNP typing in three rounds of testing. The initial whole-genome sequencing typing algorithm was 99·5% concordant across the first 20 MedSeq genomes. Addressing discordances led to development of an improved algorithm that was 99·8% concordant for the remaining 90 MedSeq genomes. Additional modifications led to the final algorithm, which was 99·2% concordant across 200 INTERVAL genomes (or 99·9% after adjustment for the lower depth of coverage). By enabling more precise antigen-matching of patients with blood donors, antigen typing based on whole-genome sequencing provides a novel approach to improve transfusion outcomes with the potential to transform the practice of transfusion medicine. National Human Genome Research Institute, Doris Duke Charitable Foundation, National Health Service Blood and Transplant, National Institute for Health Research, and Wellcome Trust.

Epidemiology of donors and recipients: lessons from the SCANDAT database.

With the development of several 'vein-to-vein' databases, which capture data on the entire donor-recipient continuum and link this data to health outcomes, there has been an increasing number of studies investigating the health effects of all aspects of the practice of transfusion medicine. The Scandinavian Donations and Transfusions (SCANDAT) database is one of several such databases, which includes all electronically available data on blood donors, donations and transfusions since the late 1960s in Sweden and the early 1980s in Denmark. The SCANDAT database has been used to characterise disease occurrence among blood donors and transfused patients, as well as to investigate possible health effects of blood donations, aspects of transfusion care and possible transfusion transmission of disease. Recent publications include studies on recipient mortality associated with the storage lesion, studies on the effects of donor demographics on patient mortality and health effects of frequent blood donation. Although this research approach is clearly very powerful, the appropriate analysis of such real-world data is complex and requires close methodological attention. The purpose of this review is to present some of the research conducted within the SCANDAT collaboration. We hope more international collaboration may help improve our understanding of the important remaining questions about donor and recipient health.

Modeling the potential impact on the US blood supply of transfusing critically ill patients with fresher stored red blood cells.

BackgroundAlthough some studies have suggested that transfusion recipients may have better medical outcomes if transfused with red blood cell units stored for a short time, the overall body of evidence shows mixed results. It is important to understand how using fresher stored red blood cell units for certain patient groups may affect blood availability.MethodsBased on the Stock-and-Flow simulation model of the US blood supply developed by Simonetti et al. 2014, we evaluated a newly implemented allocation method of preferentially transfusing fresher stored red blood cell units to a subset of high-risk group of critically ill patients and its potential impact on supply.ResultsSimulation results showed that, depending on the scenario, the US blood total supply might be reduced between 2-42%, when compared to the standard of care in transfusion medicine practice. Among our simulated scenarios, we observed that the number of expired red blood cell units modulated the supply levels. The age threshold of the required red blood cell units was inversely correlated with both the supply levels and the number of transfused units that failed to meet that age threshold.ConclusionTo our knowledge, this study represents the first attempt to develop a comprehensive framework to evaluate the impact of preferentially transfusing fresher stored red blood cells to the higher-risk critically ill patients on supply. Model results show the difficulties to identify an optimal scenario.

Determination of the frequency of the most immunogenic Rhesus antigens among Saudi donors in King Abdulaziz Medical City - Riyadh.

Background:The Rhesus (Rh) blood group system is one of the most polymorphic and immunogenic systems known in humans, because of its immunogenicity along with ABO grouping, RhD antigen testing was made mandatory before issuing a compatible blood. At present, there are five major antigens, i.e., D, C, E, c, and e in Rh blood group system.Aims:The aim of this study is to provide essential data about the distribution of the major Rh antigens and the most common phenotype among the Saudi population.Materials and Methods:This is a retrospective study to evaluate the Rh grouping and Rh sub-groups performed among some donors who donated blood or blood products at the department of donation center at King Abdulaziz Medical City Riyadh, Saudi Arabia from January 1, 2014 to December 31, 2014. Sample size included 600 donors. Donors are males and females and their ages are above 18 years.Results:The incidence of RhD was 84.8% and only 15.2% of samples were negative for D antigen. The Incidence of other Rh antigens C, E, c, and e were 62.3%, 23.5%, 74.3%, and 95.0%, respectively. The most common phenotype among RhD positive donors was DCcee (28.7%) and among RhD negative donors was dccee (13.7%). However, three donors (0.5%) were negative for antithetical antigens C and c.Conclusion:This study shows that there is a wide racial and geographical variation in the distribution of Rh antigens and phenotypes among study participants. The Rh blood group system has a vital role in population genetic study and in resolving medical legal issues and more importantly in transfusion medicine practice.

Genomic Applications for Transfusion Support

Red blood cell (RBC) and platelet antigen determination by DNA methods (genotyping) has become an important part of the practice of transfusion medicine over the past decade.The results are reliable and highly correlated with serologic phenotyping results, and are superior in some situations. Application of RBC genotyping to provide more precise transfusion therapy for various patient populations will be discussed, with a particular emphasis on those requiring chronic RBC therapy or with complex serologic reactivity. Current DNA arrays can test for a large number of blood group antigens, but routine typing of the ABO and Rh systems is not currently feasible due to the large number of genetic mutations.Patients with sickle cell disease (SCD) are one of the most challenging populations to safely transfuse, in part due to high rates of alloimmunization against Rh antigens despite prophylactic matching for D, C, and E antigens. Genotyping of the RH loci has revealed that RHD and RHCE variants are prevalent in African Blacks. Nearly 90% of patients with SCD have at least one altered RH gene and contributes to Rh alloimmunization in patients with SCD. The role of RH variation and alloimmunization in SCD will be reviewed, and the feasibility and approach to genetic RBC matching of patients and donors will be discussed. The use of targeted DNA arrays, whole exome sequencing, or whole genome sequencing to identify common and variant RH alleles will be addressed, including limitations of each method. DisclosuresNo relevant conflicts of interest to declare.

Gestion du sang du patient et pour le patient

ObjectivesIn a context of regular review of transfusion practice, the aim of this review is to present an update of the scientific basis of the so-called “patient blood management” (PBM), the state of its development in Europe, and possible ways to progress its development further in France. MethodsAnalysis and synthesis of the data from scientific literature on the scientific basis of PBM (methods, indications, efficacy, risks, efficiency). ResultsPBM appears as an evidence-based, patient centred, multidisciplinary approach, aiming to optimise the care of patients who might need transfusion and, consequently, the use of blood products. PBM is based on three pillars: optimise the patient's own blood supplies, minimise blood loss, optimise patient's tolerance of anaemia. Available scientific evidence can be considered as sufficient to consider PBM guidelines and practices as an indispensable complement to the transfusion medicine guidelines and practices. Several countries have launched PBM programmes (alternatives to allogeneic transfusion and optimisation of the use of blood components). Although current French national transfusion guidelines contain some PBM measures, PBM programmes should be further developed in France, primarily for medical reasons. ConclusionsPossible ways, using the existing basis having proved to be effective, are proposed to further develop PBM in France, as a complement to transfusion medicine, with the participation of involved stakeholders, including experts from relevant medical specialties, both at local and national levels.

Past, present and forecast of transfusion medicine: What has changed and what is expected to change?

Blood transfusion is the second most used medical procedures in health care systems worldwide. Over the last few decades, significant changes have been evolved in transfusion medicine practices. These changes were mainly needed to increase safety, efficacy, and availability of blood products as well as reduce recipients' unnecessary exposure to allogeneic blood. Blood products collection, processing, and storage as well as transfusion practices throughout all patient populations were the main stream of these changes. Health care systems across the world have adopted some or most of these changes to reduce transfusion risks, to improve overall patients' outcome, and to reduce health care costs. In this article, we are going to present and discuss some of these recent modifications and their impact on patients' safety.

Transfusion medicine in medical education: an analysis of curricular grids in Brazil and a review of the current literature.

BackgroundBlood transfusions are one of the most performed medical procedures in the world. Thus, as education in transfusion medicine is vital to medical care, it should aim to promote a responsible practice with the rational use of blood by doctors. This study aims to investigate the situation of the teaching of transfusion medicine in medical schools in Brazil.MethodThe websites of the 249 Brazilian medical schools in operation in June 2015 were visited and the curricula of the medical courses were investigated in respect to the presence or absence of a transfusion medicine discipline. When available, the subject grids were analyzed to verify whether a description of content regarding transfusion medicine was given within other disciplines.ResultsOf the 249 medical school sites visited, information on the curriculum was obtained from 178. Of the medical schools that published their curriculum, 132 (74.1%) did not have disciplines of transfusion medicine or hematology and only seven (3.9%) had a discipline of transfusion medicine in the curricular grid.ConclusionsEducation on transfusion medicine is of fundamental importance for safe and efficient transfusion practices. Deficiencies in medical knowledge of this subject have been found worldwide. The results of this study indicate a possible deficiency in teaching the basics of this specialty. Thus, additional prospective studies to assess the knowledge and practice of transfusion medicine in Brazilian medical schools are warranted, which could prompt a discussion on the importance of offering training in transfusion medicine to medical students.

The role of hemovigilance and postmarketing studies when introducing innovation into transfusion medicine practice: the amotosalen-ultraviolet A pathogen reduction treatment model.

Innovations in transfusion medicine require randomized controlled clinical trials (RCTs) to demonstrate safety and efficacy before approval; however, these studies are costly and limited in scope and may be underpowered to detect rare adverse events (AEs). Regulatory agencies, such as the Food and Drug Administration, require postmarketing surveillance, hemovigilance (HV), and controlled Phase IV studies to monitor performance and confirm safety. The INTERCEPT Blood System (IBS) is an illustrative model for implementation of a transformative technology for which sponsored active HV, regulatory authority HV, and Phase IV studies were used to extend preapproval efficacy and safety information. After CE mark registration in Europe, 13,644 patients received 76,346 IBS components prepared largely without gamma irradiation or bacterial screening in sponsored active HV studies documenting no increased incidence of AEs compared to historical controls and no increased component utilization. National HV systems in France and Switzerland specifically demonstrated no transfusion-associated graft-versus-host disease or increased incidence of transfusion-associated acute lung injury, after transfusion of 317,669 IBS platelet (PLT) components, and significant reduction of transfusion-transmitted bacterial infection as well as acute transfusion reactions. Cumulatively, these studies provide new information about safety and efficacy of IBS PLT and plasma components not obtainable from RCTs. Although inherently different from RCTs, properly designed postmarketing studies are informative regarding the safety and efficacy of innovative transfusion technologies in large patient populations under conditions of routine use.

Blood donation and ethics – personal reflections on the ISBT code of ethics

The Code of Ethics of ISBT was first published in 1980. It is a core document of the society and outlines the standards which should be applied in the practice of transfusion medicine and science. The Code has changed little since its initial publication. In recent years, however, it has been the subject of repeated criticism. A review of the Code has recently been initiated. The background to the review is outlined, and possible approaches to improving its clarity and addressing the concerns raised in recent criticisms are discussed.

2015 proceedings of the National Heart, Lung, and Blood Institute's State of the Science in Transfusion Medicine symposium.

On March 25 and 26, 2015, the National Heart, Lung, and Blood Institute sponsored a meeting on the State of the Science in Transfusion Medicine on the National Institutes of Health (NIH) campus in Bethesda, Maryland, which was attended by a diverse group of 330 registrants. The meeting's goal was to identify important research questions that could be answered in the next 5 to 10 years and which would have the potential to transform the clinical practice of transfusion medicine. These questions could be addressed by basic, translational, and/or clinical research studies and were focused on four areas: the three "classical" transfusion products (i.e., red blood cells, platelets, and plasma) and blood donor issues. Before the meeting, four working groups, one for each area, prepared five major questions for discussion along with a list of five to 10 additional questions for consideration. At the meeting itself, all of these questions, and others, were discussed in keynote lectures, small-group breakout sessions, and large-group sessions with open discourse involving all meeting attendees. In addition to the final lists of questions, provided herein, the meeting attendees identified multiple overarching, cross-cutting themes that addressed issues common to all four areas; the latter are also provided. It is anticipated that addressing these scientific priorities, with careful attention to the overarching themes, will inform funding priorities developed by the NIH and provide a solid research platform for transforming the future practice of transfusion medicine.