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Blood Nov 2022Platelet transfusions are commonly administered for the prevention or treatment of bleeding in patients with acquired thrombocytopenia across a range of clinical... (Review)
Review
Platelet transfusions are commonly administered for the prevention or treatment of bleeding in patients with acquired thrombocytopenia across a range of clinical contexts. Recent data, including randomized trials, have highlighted uncertainties in the risk-benefit balance of this therapy, which is the subject of this review. Hemovigilance systems report that platelets are the most frequently implicated component in transfusion reactions. There is considerable variation in platelet count increment after platelet transfusion, and limited evidence of efficacy for clinical outcomes, including prevention of bleeding. Bleeding events commonly occur despite the different policies for platelet transfusion prophylaxis. The underlying mechanisms of harm reported in randomized trials may be related to the role of platelets beyond hemostasis, including mediating inflammation. Research supports the implementation of a restrictive platelet transfusion policy. Research is needed to better understand the impact of platelet donation characteristics on outcomes, and to determine the optimal thresholds for platelet transfusion before invasive procedures or major surgery (eg, laparotomy). Platelet transfusion policies should move toward a risk-adapted approach that does not focus solely on platelet count.
Topics: Humans; Platelet Transfusion; Thrombocytopenia; Hemorrhage; Blood Platelets; Platelet Count
PubMed: 35926105
DOI: 10.1182/blood.2022016558 -
Transfusion Clinique Et Biologique :... Feb 2023Many patients worldwide receive platelet components (PCs) through the transfusion of diverse types of blood components. PC transfusions are essential for the treatment... (Review)
Review
Many patients worldwide receive platelet components (PCs) through the transfusion of diverse types of blood components. PC transfusions are essential for the treatment of central thrombocytopenia of diverse causes, and such treatment is beneficial in patients at risk of severe bleeding. PC transfusions account for almost 10% of all the blood components supplied by blood services, but they are associated with about 3.25 times as many severe reactions (attributable to transfusion) than red blood cell transfusions after stringent in-process leukoreduction to less than 10 residual cells per blood component. PCs are not homogeneous, due to the considerable differences between donors. Furthermore, the modes of PC collection and preparation, the safety precautions taken to limit either the most common (allergic-type reactions and febrile non-hemolytic reactions) or the most severe (bacterial contamination, pulmonary lesions) adverse reactions, and storage and conservation methods can all result in so-called PC "storage lesions". Some storage lesions affect PC quality, with implications for patient outcome. Good transfusion practices should result in higher levels of platelet recovery and efficacy, and lower complication rates. These practices include a matching of tissue ABH antigens whenever possible, and of platelet HLA (and, to a lesser extent, HPA) antigens in immunization situations. This review provides an overview of all the available information relating to platelet transfusion, from donor and donation to bedside transfusion, and considers the impact of the measures applied to increase transfusion efficacy while improving safety and preventing transfusion inefficacy and refractoriness. It also considers alternatives to platelet component (PC) transfusion.
Topics: Humans; Adult; Platelet Transfusion; Blood Platelets; Thrombocytopenia; Blood Transfusion; Blood Component Transfusion
PubMed: 36031180
DOI: 10.1016/j.tracli.2022.08.147 -
Platelets Jan 2022The neonatal hemostatic system is different from that of adults. The differences in levels of procoagulant and anticoagulant factors and the evolving equilibrium in... (Review)
Review
The neonatal hemostatic system is different from that of adults. The differences in levels of procoagulant and anticoagulant factors and the evolving equilibrium in secondary hemostasis during the transition from fetal/neonatal life to infancy, childhood, and adult life are known as "developmental hemostasis." In regard to primary hemostasis, while the number (150,000-450,000/µl) and structure of platelets in healthy neonates closely resemble those of adults, there are significant functional differences between neonatal and adult platelets. Specifically, platelets derived from both cord blood and neonatal peripheral blood are less reactive than adult platelets to agonists, such as adenosine diphosphate (ADP), epinephrine, collagen, thrombin, and thromboxane (TXA) analogs. This platelet hyporeactivity is due to differences in expression levels of key surface receptors and/or in signaling pathways, and is more pronounced in preterm neonates. Despite these differences in platelet function, bleeding times and PFA-100 closure times (an test of whole-blood primary hemostasis) are shorter in healthy full-term infants than in adults, reflecting enhanced primary hemostasis. This paradoxical finding is explained by the presence of factors in neonatal blood that increase the platelet-vessel wall interaction, such as high von Willebrand factor (vWF) levels, predominance of ultralong vWF multimers, high hematocrit, and high red cell mean corpuscular volume. Thus, the hyporeactivity of neonatal platelets should not be viewed as a developmental deficiency, but rather as an integral part of a developmentally unique, but well balanced, primary hemostatic system. In clinical practice, due to the high incidence of bleeding (especially intraventricular hemorrhage, IVH) among preterm infants, neonatologists frequently transfuse platelets to non-bleeding neonates when platelet counts fall below an arbitrary limit, typically higher than that used in older children and adults. However, recent studies have shown that prophylactic platelet transfusions not only fail to decrease bleeding in preterm neonates, but are associated with increased neonatal morbidity and mortality. In this review, we will describe the developmental differences in platelet function and primary hemostasis between neonates and adults, and will analyze the implications of these differences to platelet transfusion decisions.
Topics: Blood Platelets; Humans; Platelet Transfusion
PubMed: 34392772
DOI: 10.1080/09537104.2021.1962837 -
Blood May 2021
Topics: Platelet Count; Platelet Transfusion
PubMed: 33983425
DOI: 10.1182/blood.2021011269 -
Deutsches Arzteblatt International Nov 2014The standard recommendation to date has been that acute hypoproliferative thrombocytopenia should be treated with a prophylactic platelet transfusion if the morning... (Review)
Review
BACKGROUND
The standard recommendation to date has been that acute hypoproliferative thrombocytopenia should be treated with a prophylactic platelet transfusion if the morning platelet count is less than 10 000/μL, or less than 20 000/μL if there are additional risk factors. For chronic thrombocytopenia, transfusion has been recommended if the platelet count is less than 5000/μL. In Germany, half a million platelet transfusions are now being given every year, and the number is rising. New studies indicate, however, that a more restrictive transfusion strategy is justified.
METHODS
A selective literature search was carried out in PubMed, with additional attention to recommendations from Germany and abroad, and to the guidelines of medical specialty societies.
RESULTS
Prophylactic platelet transfusions should be given when clinically indicated in consideration of the individual hemorrhagic risk. To prevent severe hemorrhage, it is more important to respond to the first signs of bleeding than to pay exclusive attention to morning platelet counts below 10 000/μL. This threshold value remains standard for patients with acute leukemia. According to recent studies, however, clinically stable patients who are at low risk for bleeding-e.g., patients who have undergone autologous hematopoietic stem-cell transplantation-may be well served by a therapeutic, rather than prophylactic, platelet transfusion strategy, in which platelets are transfused only when evidence of bleeding has been observed. For cancer patients, intensive-care patients, and patients with other risk factors, a clinically oriented transfusion strategy is recommended, in addition to close attention to threshold platelet values.
CONCLUSION
The number of platelet transfusions could be safely lowered by a more restrictive transfusion strategy that takes account of the risk of bleeding, as recommended in the hemotherapy guidelines.
Topics: Antineoplastic Agents; Evidence-Based Medicine; Germany; Hematology; Humans; Medical Oncology; Neoplasms; Platelet Transfusion; Postoperative Hemorrhage; Practice Guidelines as Topic; Thrombocytopenia; Treatment Outcome
PubMed: 25512006
DOI: 10.3238/arztebl.2014.0809 -
Blood Advances Feb 2019Although the hemostatic potential of adult platelets has been investigated extensively, regulation of platelet function during fetal life is less clear. Recent studies... (Review)
Review
Although the hemostatic potential of adult platelets has been investigated extensively, regulation of platelet function during fetal life is less clear. Recent studies have provided increasing evidence for a developmental control of platelet function during fetal ontogeny. Fetal platelets feature distinct differences in reactive properties compared with adults. These differences very likely reflect a modified hemostatic and homeostatic environment in which platelet hyporeactivity contributes to prevent pathological clot formation on the one hand but still ensures sufficient hemostasis on the other hand. In this review, recent findings on the ontogeny of platelet function and reactivity are summarized, and implications for clinical practice are critically discussed. This includes current platelet-transfusion practice and its potential risk in premature infants and neonates.
Topics: Animals; Blood Platelets; Hemostasis; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature; Platelet Activation; Platelet Adhesiveness; Platelet Count; Platelet Transfusion; Thrombocytopenia; Thrombopoiesis
PubMed: 30808687
DOI: 10.1182/bloodadvances.2018024372 -
Blood Transfusion = Trasfusione Del... Mar 2016Platelet concentrates account for near 10% of all labile blood components but are responsible for more than 25% of the reported adverse events. Besides factors related... (Review)
Review
Platelet concentrates account for near 10% of all labile blood components but are responsible for more than 25% of the reported adverse events. Besides factors related to patients themselves, who may be particularly at risk of side effects because of their underlying illness, there are aspects of platelet collection and storage that predispose to adverse events. Platelets for transfusion are strongly activated by collection through disposal equipment, which can stress the cells, and by preservation at 22 °C with rotation or rocking, which likewise leads to platelet activation, perhaps more so than storage at 4 °C. Lastly, platelets constitutively possess a very large number of bioactive components that may elicit pro-inflammatory reactions when infused into a patient. This review aims to describe approaches that may be crucial to minimising side effects while optimising safety and quality. We suggest that platelet transfusion is complex, in part because of the complexity of the "material" itself: platelets are highly versatile cells and the transfusion process adds a myriad of variables that present many challenges for preserving basal platelet function and preventing dysfunctional activation of the platelets. The review also presents information showing--after years of exhaustive haemovigilance--that whole blood buffy coat pooled platelet components are extremely safe compared to the gold standard (i.e. apheresis platelet components), both in terms of acquired infections and of immunological/inflammatory hazards.
Topics: Blood Preservation; Blood Safety; Humans; Platelet Transfusion
PubMed: 26674828
DOI: 10.2450/2015.0042-15 -
British Journal of Haematology Feb 2017
Topics: Guidelines as Topic; Humans; Platelet Transfusion
PubMed: 28009056
DOI: 10.1111/bjh.14423 -
Arteriosclerosis, Thrombosis, and... Jun 2023
Topics: Infant, Newborn; Humans; Platelet Transfusion; Hemostasis; Thrombocytopenia
PubMed: 37139838
DOI: 10.1161/ATVBAHA.123.319252 -
Current Opinion in Hematology Nov 2020In this review, we discuss current clinical guidelines and potential underlying mechanisms regarding platelet transfusion therapy in patients at risk of bleeding,... (Review)
Review
PURPOSE OF REVIEW
In this review, we discuss current clinical guidelines and potential underlying mechanisms regarding platelet transfusion therapy in patients at risk of bleeding, comparing management of patients with thrombocytopenia versus those with qualitative platelet disorders.
RECENT FINDINGS
Platelet transfusion therapy is highly effective in managing bleeding in patients with hypoproliferative thrombocytopenia. Clinical trials have demonstrated that platelet transfusion can be used at a lower trigger threshold and reduced platelet doses, and may be used therapeutically rather than prophylactically in some situations, although additional data are needed. In patients with inherited platelet disorders such as Glanzmann's Thrombasthenia or those with RASGRP2 mutations, platelet transfusion may be ineffective because of competition between transfused and endogenous platelets at the site of vascular injury. Successful management of these patients may require transfusion of additional platelet units, or mechanism-driven combination therapy with other pro-hemostatic agents. In patients on antiplatelet therapy, timing of transfusion and inhibitor mechanism-of-action are key in determining therapeutic success.
SUMMARY
Expanding our understanding of the mechanisms by which transfused platelets exert their pro-hemostatic function in various bleeding disorders will improve the appropriate use of platelet transfusion.
Topics: Animals; Blood Platelet Disorders; Hemorrhage; Hemostasis; Hemostatics; Humans; Platelet Aggregation Inhibitors; Platelet Transfusion
PubMed: 32868672
DOI: 10.1097/MOH.0000000000000608