Transfusion Medicine

2011 ◽  
Author(s):  
Harvey G Klein

Transfusion medicine has advanced to a laboratory-based clinical discipline because of key discoveries and technical advances. These include the discovery of blood group antigens and the understanding of the host immune response to these antigens, development of methods of anticoagulation and storage of blood, and creation of plastic bags that allow sterile fractionation of whole blood into components. The potential of blood to act as an agent of disease transmission has heavily shaped both the donation process and transfusion practice. This chapter offers information to help the physician decide whether to transfuse. It includes sections on blood donation (autologous and directed), on postdonation screening procedures for the presence of viral agents (e.g., hepatitis, retrovirus, and emerging infectious pathogens), on pretransfusion testing (i.e., antigen phenotyping and testing for the presence of antibodies), and on blood components. Sections give specific information on transfusion of red cells, platelets, fresh frozen plasma, and recombinant clotting factors. Indications and complications of apheresis are described. Complications of transfusions are discussed, as are future prospects for transfusion therapy. Tables detail the advantages and disadvantages of autologous donation, estimated risks of blood transfusion, characteristics of blood products and indications for their use, plasma and recombinant clotting factors, indications for recombinant factor VIIa therapy, indications for the use of irradiated blood products, indications for the use of cytomegalovirus-negative blood products, and recommendations for therapeutic apheresis. This chapter contains 154 references.

2011 ◽  
Author(s):  
Harvey G Klein

Transfusion medicine has advanced to a laboratory-based clinical discipline because of key discoveries and technical advances. These include the discovery of blood group antigens and the understanding of the host immune response to these antigens, development of methods of anticoagulation and storage of blood, and creation of plastic bags that allow sterile fractionation of whole blood into components. The potential of blood to act as an agent of disease transmission has heavily shaped both the donation process and transfusion practice. This chapter offers information to help the physician decide whether to transfuse. It includes sections on blood donation (autologous and directed), on postdonation screening procedures for the presence of viral agents (e.g., hepatitis, retrovirus, and emerging infectious pathogens), on pretransfusion testing (i.e., antigen phenotyping and testing for the presence of antibodies), and on blood components. Sections give specific information on transfusion of red cells, platelets, fresh frozen plasma, and recombinant clotting factors. Indications and complications of apheresis are described. Complications of transfusions are discussed, as are future prospects for transfusion therapy. Tables detail the advantages and disadvantages of autologous donation, estimated risks of blood transfusion, characteristics of blood products and indications for their use, plasma and recombinant clotting factors, indications for recombinant factor VIIa therapy, indications for the use of irradiated blood products, indications for the use of cytomegalovirus-negative blood products, and recommendations for therapeutic apheresis. This chapter contains 154 references.


2016 ◽  
Vol 3 (1) ◽  
pp. 45-49
Author(s):  
Youssef Moutaouakkil ◽  
◽  
Rachid Eldjaoudi ◽  
Sanaa Makram ◽  
Jamal Lamsaouri ◽  
...  

The stable blood products, called since 1995 “the medicines derived from blood”, are classified into five categories (albumin, clotting factors, protease inhibitors, immunoglobulins, biological glues). Their manufacture, dispensing, and pharmacovigilance (Correspendants) are provided primarily by the pharmacist. They have a great importance in the compensation of constitutional or acquired deficiency of plasma proteins. Obtaining them from blood donation (voluntary, anonymous and free), requires the application of several successive fractionation, merging, purification, elimination and/or viral inactivation. The main techniques used in fractionation are, precipitation (by cold or ethanol) and chromatography, which also contributes to the reduction of a possible viral load. The viral securisation is a decisive criterion for evaluation of the drug under the authorization of placing on the market. Other recombinant products have been developed ; they have the advantage of being equally effective but safer then plasma products. We propose in our work to review key points on securing viral transmission of medicines derived from blood.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 18-19
Author(s):  
Maria do Rosario Ferraz Roberti ◽  
Tiago Paiva Prudente ◽  
Renato Gomes Castro ◽  
Marcos Antonio Candido ◽  
Roberta Luiza Rodrigues ◽  
...  

In Brazil, until the 1980s, the context of blood as transfusion therapy was marked by paid donations. Thus, self-interest has surpassed solidarity as a motivator to donate. Recruiting donors involves advising the population due to the difficulties related to the myths around donation. With the COVID-19 pandemic, recruiting convalescent plasma (CP) donors has been a hard. This is an observational, prospective and non-interventionist study carried out in a hemotherapy unit of the Unified Health System, in central-western Brazil. Data collection was carried out from 06/19/2020 to 07/31/2020. The subjects were contacted by the Recruitment and Collection (CR) sector, through an active search, using lists of patients previously diagnosed with COVID-19. The study was also published on social and traditional networks, which resulted in self-reference. Convalescent COVID-19 patients tested, of both genders, aged between 18 and 60 years, weight over 60 kg, without symptoms for more than 14 days, and nulliparous donors were invited to the study. Those who met the criteria were scheduled for clinical and serological screening. The subjects eligible for donation, with IgG reagent, signed the Free and Informed Consent Form. Individuals with positive RT-PCR and / or non-reactive IgG were excluded. During the study period, RC made 308 and received 1,797 calls (2,105 contacts), generating 242 (11.5%) screening appointments, 173 (8.2%) of which resulted from self-referral and 69 (3.2%) from active search. Of these, 131 (6.2%) subjects attended the appointment. After clinical screening, 37 (28.25%) subjects were ineligible, 37 (28.25%) after serological tests and 57 (43.5%) were eligible for donation. The ineligibility causes in clinical and serological screening are described in table 1. Many countries face difficulties in meeting the demand for blood and its components during the pandemic (Barone & DeSimone. Transfusion, 2020), especially in those where blood commercialization is prohibited, as in Brazil. The purpose of recruiting donors is to make blood donation habitual to Brazilians, as it occurs in developed countries. Figure 2 shows self-referral rates after dissemination in traditional media. The ads focused on the donor's ability to save lives by encouraging altruism (Ronse, et al. 2018).On the other hand, despite attracting more people, most were not eligible for donation, demonstrating a great capacity to raise awarenessamong the population, but it was necessary to improve criterias and demonstrate them clearly for the likely donor. Of the 26 donors, 22 (84.6%) are older than 29. For these, awareness-raising occurred mainly through the television media 9(34.6%) and 5(19.3%) through personal contact. In the youngest 4(15.4%), the stimulus was social networks (Sümnig, et al. Transfusion, 2018). Marketing was important for recruitment. As blood donation is not usual for most brazilians, it is essential to plan, develop, evaluate strategies, enabling new forms of collection. Another difficulty encountered was the logistics for this donation type. As the donor is convalescent, the recruitment, screening, and collection was restricted to a physical space, isolated from conventional donos (Bloch, et al. J Clin Invest. 2020). In conclusion, the COVID-19 pandemic has become a public health challenge worldwide. Many recovered patients could donate CP. However, it is necessary to define the ideal requirements for donor selection to ensure the therapeutic viability and efficacy of PC transfusion. Blood collection teams need to strengthen strategies to inform the population about blood donation needs. The information available in the traditional and digital media about the donation process can increase the donation rate and guarantee a safe blood component. Strategies such as a greater number of insertions in social networks with well-defined criteria for donating plasma from a convalescent donor, clarification of exclusion criteria in the means of greater reach, creation of easily accessible channels to the donor (registrations, central doubts),in addition to stratifying by age group and proposing different dissemination strategies and thanksgiving for the donation, forming a network of donations. The combined efforts of these actions will contribute with expert advice and experience, technical guidance and additional support to potentially save more lives. Disclosures No relevant conflicts of interest to declare.


2021 ◽  
Author(s):  
Moataz Dowaidar

In adults, normal hematopoiesis occurs in the bone marrow, producing leukocytes, red blood cells, and platelets. Recently, megakaryocytes have been found in mouse lungs and spleen, where they release platelets by blood flow force. Blood products are used to treat a multitude of diseases and conditions that generate cytopenia. The blood transfusion system must be enhanced due to a drop in blood donors due to low birth rate and changing attitudes among young people, pathogen contamination, and rising demand due to chronic blood diseases that are prevalent among the elderly. Pluripotent stem cells, such as embryonic stem (ES) cells, may proliferate in vitro indefinitely and are a prospective source for blood transfusions to replace blood donations.Platelet preparations can be maintained at room temperature to sustain platelet function, but only have a statutory expiry date of five days. Platelets are anucleate cells, thus irradiation before blood donation can lessen the risk of iPS cell infection. Effective treatment requires HLA-compatible platelet transfusions, although supply limits often leave patients underserved. CRISPR/Cas9 has made it viable to make HLA class I-deleted blood products to avoid rejection and lower the odds of platelet-expressed human leukocyte antigen Class I cancer-causing iPS cells (HLA-I). This article discusses the production of megakaryocyte cell lines, bioreactors, and scale-up cultures, as well as identifying viable drugs in manufacturing. HLA-null, iPSC-derived platelet products' universal potential will also be explored.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
John Porter

For reasons of time, this short talk will be confined to the optimal frequency, timing, indications and dosing of blood transfusion. Blood transfusion protocols in thalassaemia syndromes are more widely agreed (1) than for sickle disorders but questions still remain about optimal Hb levels, timing and frequency. In transfusion thalassaemia thalassaemias (TDT) , the purpose of blood transfusion is to maximise quality of life by correcting anaemia and suppressing ineffective erythropoiesis, whilst minimising the complications of the transfusion itself. Under-transfusion will limit growth and physical activity while increasing intramedullary and extra-medullary erythroid expansion. Over transfusion may cause unnecessary iron loading and increased risk of extra-hepatic iron deposition however. Although guidelines imply a ‘one size fits all’ approach to transfusion, in reality this is not be the case. Indeed a flexible approach crafted to the patient’s individual requirements and to the local availability of safe blood products is needed for optimal outcomes. For example in HbEβ thalassaemias, the right shifted oxygen dissociation curve tends to lead to better oxygen delivery per gram of Hb than in β thalassaemia intermedia with high Hb F. Patients with Eβthal therefore tend to tolerate lower Hb values than β thalassaemia intermedia. Guidelines aim to balance the benefits of oxygenation and suppression of extra-medullary expansion with those of excessive iron accumulation from overtransfusion. In an Italian TDT population, this balance was optimised with pre-transfusion values of 9.5-10.5g/dl (2). However this may not be universally optimal because of different levels of endogenous erythropoiesis with different genotypes in different populations. Recent work by our group (3) suggests that patients with higher levels of endogenous erythropoiesis, marked by higher levels of soluble transferrin receptors, at significantly lower risk of cardiac iron deposition than in those where endogenous erythropoiesis is less active, as would be the case in transfusion regimes achieving higher levels of pre-transfusion Hb. In sickle cell disorders, the variability in the phenotype between patients and also within a single patient at any given time means that the need for transfusion also varies. A consideration in sickle disorders, not usually applicable to thalassaemia syndromes, is that of exchange transfusion versus simple top up transfusion. Exchanges have the advantages of lower iron loading rates and more rapid lowering of HbS%. Disadvantages of exchange transfusion are of increased exposure to blood products with inherent increased risk of allo-immunisation or infection, requirement for better venous access for adequate blood flow, and requirements for team of operators capable of performing either manual or automated apheresis, often at short notice. Some indications for transfusion in sickle disorders are backed up by randomised controlled data, such as for primary and secondary stroke prevention, or prophylaxis of sickle related complications for high-risk operations (4). Others are widely practiced as standard of care without randomised data, such as treatment of acute sickle chest syndrome. Other indications for transfusion, not backed up by randomised studies, but still widely practiced in selected cases, include the management of pregnancy, leg ulceration or priapism and repeaed vaso-occlusive crises. Allo-immunisation is more common in sickle patients than in thalassaemia disorders and hyper-haemolysis is a rare but growing serious problem in sickle disorders. It is arguable that increased use of transfusion early in life, is indicated to decrease silent stroke rates and that early exposure to blood will decease red cell allo-immunisation rates.


Blood ◽  
1990 ◽  
Vol 76 (9) ◽  
pp. 1680-1697 ◽  
Author(s):  
RC Woodman ◽  
LA Harker

Bleeding after CPB has been difficult to characterize and its treatment equally difficult to standardize. The complexity of this problem is related to the hemostatic process, the technical variations in the operative procedures, and the many uncontrolled variables associated with CPB, including the effects of anesthetic or pharmacologic agents, the nature of the priming solution, hemodilution, hypothermia, the type of oxygenator, and the use of transfused blood products. Although there are multiple and generally predictable complex changes in the hemostatic mechanism during CPB, the temporary loss of platelet function is the most common and clinically relevant. This transient platelet dysfunction occurs in all patients undergoing CPB; however, it only causes excessive bleeding in a small percentage of patients. Unfortunately, it has not yet been possible to predict which patients will develop hemorrhagic complications, although prolonged pump times are a contributing risk factor. Over the past decade there has been extensive investigation into the management of bleeding associated with CPB, provoked primarily by the increased awareness of transfusion- transmitted viral diseases and the inappropriately excessive use of homologous blood products. Several approaches to autotransfusion of shed blood and autologus blood donation have been developed to minimize perioperative homologous blood transfusion. Pharmacologic agents such as desmopressin, aprotinin, and topical fibrin glues have also been introduced to improve hemostasis during CPB. The protease inhibitor aprotinin is particularly promising in the reduction of bleeding associated with CPB when given prophylactically. Aprotinin may provide new insights into the mechanism of CPB-induced platelet dysfunction. Desmopressin is indicated only for the treatment of bleeding after CPB. The management of bleeding associated with CPB will undoubtedly


Author(s):  
Karen van den Berg

Despite numerous publications on the appropriate use of blood and blood products, few specifically consider the role of transfusion in the management of HIV. This review is a synthesis of conditions encountered in the management of HIV-infected patients where the transfusion of blood or blood products may be indicated. A consistent message emerging from the review is that the principles of transfusion medicine do not differ between HIV-negative and -positive patients. The aim of the review is to provide clinicians with a practical and succinct overview of the haematological abnormalities and clinical circumstances most commonly encountered in the HIV setting, while focusing on the rational and appropriate use of blood and blood products for HIV patients. Important ethical considerations in dealing with both the collection and transfusion blood and blood products in the HIV era have also been addressed. S Afr J HIV Med 2012;13(2):87-103.


Hematologies ◽  
2019 ◽  
pp. 178-201
Author(s):  
Jacob Copeman ◽  
Dwaipayan Banerjee

This chapter focuses on blood in the time of the civic—that is, blood that is donated voluntarily as a dutiful contribution to civic life, that in turn ensures the continued efficacy and productivity of transfusion medicine. These voluntary donations take place according to a seemingly simple biological time map: the biological time of cellular production determines the biomedically mandated three-month gap between donations. The time regime of the repeated voluntary donation emerges from and is mapped upon the lifetime of blood cells. This is in contrast to apparently less civic-minded blood donation modes: the potentially dangerous commercial transaction of paid blood donation and the one-time mode of “replacement” donation, performed in order to release blood for the benefit of one's immediate family member in need of transfusion. As this chapter shows, these modes of donation are characterized by different temporalities. A routine of dutiful repetitive bloodshed structures voluntary blood donation's time of the civic.


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