Intravenous iron therapy results in rapid and sustained rise in myocardial iron content through a novel pathway.

BACKGROUND AND AIMS: Intravenous iron therapies contain iron-carbohydrate complexes, designed to ensure iron becomes bioavailable via the intermediary of spleen and liver reticuloendothelial macrophages. How other tissues obtain and handle this iron remains unknown. This study addresses this question in the context of the heart. METHODS: A prospective observational study was conducted in 12 patients receiving ferric carboxymaltose (FCM) for iron deficiency. Myocardial, spleen, and liver magnetic resonance relaxation times and plasma iron markers were collected longitudinally. To examine the handling of iron taken up by the myocardium, intracellular labile iron pool (LIP) was imaged in FCM-treated mice and cells. RESULTS: In patients, myocardial relaxation time T1 dropped maximally 3 h post-FCM, remaining low 42 days later, while splenic T1 dropped maximally at 14 days, recovering by 42 days. In plasma, non-transferrin-bound iron (NTBI) peaked at 3 h, while ferritin peaked at 14 days. Changes in liver T1 diverged among patients. In mice, myocardial LIP rose 1 h and remained elevated 42 days after FCM. In cardiomyocytes, FCM exposure raised LIP rapidly. This was prevented by inhibitors of NTBI transporters T-type and L-type calcium channels and divalent metal transporter 1. CONCLUSIONS: Intravenous iron therapy with FCM delivers iron to the myocardium rapidly through NTBI transporters, independently of reticuloendothelial macrophages. This iron remains labile for weeks, reflecting the myocardium's limited iron storage capacity. These findings challenge current notions of how the heart obtains iron from these therapies and highlight the potential for long-term dosing to cause cumulative iron build-up in the heart.

Intraoperative cell salvage using swab wash and serial thromboelastography in elective abdominal aortic aneurysm surgery involving massive blood loss.

The loss of 50% blood volume is one accepted definition of massive haemorrhage, which ordinarily would trigger the massive transfusion protocol, involving the administration of high ratios of fresh frozen plasma and platelets to allogeneic red cells. We investigated 53 patients who experienced >50% blood loss during open elective abdominal aortic aneurysm surgery to assess allogeneic blood component usage and coagulopathy. Specialist patient blood management practitioners used a tailored cell salvage technique including swab wash to maximise blood return. We assessed the proportion of patients who did not require allogeneic blood components and develop evidence of coagulopathy by thromboelastography (TEG) parameters. Blood loss was 50%-174% (mean [SD] 68% [27%]) of blood volume. The mean (SD) intraoperative decrease in haemoglobin concentration, assessed by arterial blood gas analysis, was 5 (13) g/l. No patient received allogeneic red cells intraoperatively. Four of the 53 (8%) patients received blood components in the first 24 h postoperatively at the anaesthetists' discretion. No patient had intraoperative TEG changes indicative of fibrinolysis or coagulopathy. The 30-day mortality was 2% (one of 53). Reduction of allogeneic transfusion is one aim of patient blood management techniques. We have demonstrated virtual avoidance of allogeneic blood product transfusion despite massive blood loss. These data show possible alternatives to the current massive transfusion protocols to the management of elective vascular surgical patients.

Drug-induced thrombotic thrombocytopenic purpura: A systematic review and review of European and North American pharmacovigilance data.

Many medications have been reported to be associated with thrombotic thrombocytopenic purpura (TTP) through pharmacovigilance data and published case reports. Whilst there are existing data available regarding drug-induced thrombotic microangiopathy, there is no available synthesis of evidence to assess drug-induced TTP (DI-TTP). Despite this lack of evidence, patients with TTP are often advised against using many medications due to the theoretical risk of DI-TTP. This systematic review evaluated the evidence for an association of medications reported as potential triggers for TTP. Of 5098 records available 261 articles were assessed further for eligibility. Fifty-seven reports, totalling 90 patients, were included in the final analysis. There were no cases where the level of association was rated as definite or probable, demonstrating a lack of evidence of any drug causing DI-TTP. This paucity of evidence was also demonstrated in the pharmacovigilance data, where 613 drugs were reported as potential causes of TTP without assessment of the strength of association. This systematic review demonstrates the need for standardised reporting of potential drugs causing TTP. Many reports omit basic information and, therefore, hinder the chance of finding a causative link if one exists.

Real-world experience with caplacizumab in the management of acute TTP.

The cornerstone of life-saving therapy in immune-mediated thrombotic thrombocytopenic purpura (iTTP) has been plasma exchange (PEX) combined with immunomodulatory strategies. Caplacizumab, a novel anti-von Willebrand factor nanobody trialed in 2 multicenter randomized controlled trials (RCTs) leading to European Union and US Food and Drug Administration approval, has been available in the United Kingdom (UK) through a patient access scheme. Data were collected retrospectively from 2018 to 2020 for 85 patients (4 children) receiving caplacizumab from 22 UK hospitals. Patient characteristics and outcomes in the real-world clinical setting were compared with caplacizumab trial end points and historical outcomes in the precaplacizumab era. Eighty-four of 85 patients received steroid and rituximab alongside PEX; 26% required intubation. Median time to platelet count normalization (3 days), duration of PEX (7 days), and hospital stay (12 days) were comparable with RCT data. Median duration of PEX and time from PEX initiation to platelet count normalization were favorable compared with historical outcomes (P < .05). Thrombotic thrombocytopenic purpura (TTP) recurred in 5 of 85 patients; all had persistent ADAMTS13 activity < 5 IU/dL. Of 31 adverse events in 26 patients, 17 of 31 (55%) were bleeding episodes, and 5 of 31 (16%) were thrombotic events (2 unrelated to caplacizumab); mortality was 6% (5/85), with no deaths attributed to caplacizumab. In 4 of 5 deaths, caplacizumab was introduced >48 hours after PEX initiation (3-21 days). This real-world evidence represents the first and largest series of TTP patients, including pediatric patients, receiving caplacizumab outside of clinical trials. Representative of true clinical practice, the findings provide valuable information for clinicians treating TTP globally.

Haemostatic therapies for stroke due to acute, spontaneous intracerebral haemorrhage.

BACKGROUND: Outcome after acute spontaneous (non-traumatic) intracerebral haemorrhage (ICH) is influenced by haematoma volume. ICH expansion occurs in about 20% of people with acute ICH. Early haemostatic therapy might improve outcome by limiting ICH expansion. This is an update of a Cochrane Review first published in 2006, and last updated in 2018. OBJECTIVES: To examine 1. the effects of individual classes of haemostatic therapies, compared with placebo or open control, in adults with acute spontaneous ICH, and 2. the effects of each class of haemostatic therapy according to the use and type of antithrombotic drug before ICH onset. SEARCH METHODS: We searched the Cochrane Stroke Trials Register, CENTRAL (2022, Issue 8), MEDLINE Ovid, and Embase Ovid on 12 September 2022. To identify further published, ongoing, and unpublished randomised controlled trials (RCTs), we scanned bibliographies of relevant articles and searched international registers of RCTs in September 2022. SELECTION CRITERIA: We included RCTs of any haemostatic intervention (i.e. procoagulant treatments such as clotting factor concentrates, antifibrinolytic drugs, platelet transfusion, or agents to reverse the action of antithrombotic drugs) for acute spontaneous ICH, compared with placebo, open control, or an active comparator. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcome was death/dependence (modified Rankin Scale (mRS) 4 to 6) by day 90. Secondary outcomes were ICH expansion on brain imaging after 24 hours, all serious adverse events, thromboembolic adverse events, death from any cause, quality of life, mood, cognitive function, Barthel Index score, and death or dependence measured on the Extended Glasgow Outcome Scale by day 90. MAIN RESULTS: We included 20 RCTs involving 4652 participants: nine RCTs of recombinant activated factor VII (rFVIIa) versus placebo/open control (1549 participants), eight RCTs of antifibrinolytic drugs versus placebo/open control (2866 participants), one RCT of platelet transfusion versus open control (190 participants), and two RCTs of prothrombin complex concentrates (PCC) versus fresh frozen plasma (FFP) (47 participants). Four (20%) RCTs were at low risk of bias in all criteria. For rFVIIa versus placebo/open control for spontaneous ICH with or without surgery there was little to no difference in death/dependence by day 90 (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.74 to 1.05; 7 RCTs, 1454 participants; low-certainty evidence). We found little to no difference in ICH expansion between groups (RR 0.81, 95% CI 0.56 to 1.16; 4 RCTs, 220 participants; low-certainty evidence). There was little to no difference in all serious adverse events and death from any cause between groups (all serious adverse events: RR 0.81, 95% CI 0.30 to 2.22; 2 RCTs, 87 participants; very low-certainty evidence; death from any cause: RR 0.78, 95% CI 0.56 to 1.08; 8 RCTs, 1544 participants; moderate-certainty evidence). For antifibrinolytic drugs versus placebo/open control for spontaneous ICH, there was no difference in death/dependence by day 90 (RR 1.00, 95% CI 0.93 to 1.07; 5 RCTs, 2683 participants; high-certainty evidence). We found a slight reduction in ICH expansion with antifibrinolytic drugs for spontaneous ICH compared to placebo/open control (RR 0.86, 95% CI 0.76 to 0.96; 8 RCTs, 2866 participants; high-certainty evidence). There was little to no difference in all serious adverse events and death from any cause between groups (all serious adverse events: RR 1.02, 95% CI 0.75 to 1.39; 4 RCTs, 2599 participants; high-certainty evidence; death from any cause: RR 1.02, 95% CI 0.89 to 1.18; 8 RCTs, 2866 participants; high-certainty evidence). There was little to no difference in quality of life, mood, or cognitive function (quality of life: mean difference (MD) 0, 95% CI -0.03 to 0.03; 2 RCTs, 2349 participants; mood: MD 0.30, 95% CI -1.98 to 2.57; 2 RCTs, 2349 participants; cognitive function: MD -0.37, 95% CI -1.40 to 0.66; 1 RCTs, 2325 participants; all high-certainty evidence). Platelet transfusion likely increases death/dependence by day 90 compared to open control for antiplatelet-associated ICH (RR 1.29, 95% CI 1.04 to 1.61; 1 RCT, 190 participants; moderate-certainty evidence). We found little to no difference in ICH expansion between groups (RR 1.32, 95% CI 0.91 to 1.92; 1 RCT, 153 participants; moderate-certainty evidence). There was little to no difference in all serious adverse events and death from any cause between groups (all serious adverse events: RR 1.46, 95% CI 0.98 to 2.16; 1 RCT, 190 participants; death from any cause: RR 1.42, 95% CI 0.88 to 2.28; 1 RCT, 190 participants; both moderate-certainty evidence). For PCC versus FFP for anticoagulant-associated ICH, the evidence was very uncertain about the effect on death/dependence by day 90, ICH expansion, all serious adverse events, and death from any cause between groups (death/dependence by day 90: RR 1.21, 95% CI 0.76 to 1.90; 1 RCT, 37 participants; ICH expansion: RR 0.54, 95% CI 0.23 to 1.22; 1 RCT, 36 participants; all serious adverse events: RR 0.27, 95% CI 0.02 to 3.74; 1 RCT, 5 participants; death from any cause: RR 0.49, 95% CI 0.16 to 1.56; 2 RCTs, 42 participants; all very low-certainty evidence). AUTHORS' CONCLUSIONS: In this updated Cochrane Review including 20 RCTs involving 4652 participants, rFVIIa likely results in little to no difference in reducing death or dependence after spontaneous ICH with or without surgery; antifibrinolytic drugs result in little to no difference in reducing death or dependence after spontaneous ICH, but result in a slight reduction in ICH expansion within 24 hours; platelet transfusion likely increases death or dependence after antiplatelet-associated ICH; and the evidence is very uncertain about the effect of PCC compared to FFP on death or dependence after anticoagulant-associated ICH. Thirteen RCTs are ongoing and are likely to increase the certainty of the estimates of treatment effect.

Real world reduction in red cell transfusion with restrictive transfusion threshold in haematology inpatients.

OBJECTIVES: The aim of this study was to assess the reduction in red cell transfusions following a change in the red cell transfusion threshold for haematology inpatients from 80 to 70 g/L. BACKGROUND: Haematology patients are among the high users of red blood cells. We reduced the threshold for transfusion of haematology inpatients to 70 g/L. This was based on evidence provided by randomised controlled trial published in 2020 that showed restrictive transfusion is non-inferior to liberal transfusion. METHOD: We assessed red cell transfusions for haematology inpatients at Oxford University Hospitals NHS Foundation Trust for 9 months before and 9 months after a change in red cell transfusion threshold from 80 to 70 g/L. RESULTS: After the change in threshold to 70 g/L or less from 80 g/L, the median number of red cell transfusions per month reduced to 88 from 111. This was a 23% reduction in the total number of red cells administered per month. CONCLUSION: These results show the real-world reductions in transfusion that can be made by putting local transfusion guidelines in line with the international recommendations. This is of particular importance at a time of national blood shortage.

Factor VIII levels and bleeding according to factor 8 (F8) mutation in pregnant carriers of haemophilia A: a multicentre retrospective cohort study.

This retrospective cohort study investigated the association between factor 8 (F8) genotype severity and factor VIII (FVIII) levels during pregnancy for 52 women (64 pregnancies) who were heterozygous carriers of mild, moderate or severe haemophilia A. There were no significant differences in FVIII levels for carriers of mild, moderate or severe haemophilia A at baseline [mean (SD) level: mild, 0·78 (0·22); moderate, 0·83 (0·33); severe, 0·70 (0·25) iu/ml; P = 0·81] or in the third trimester [mean (SD) level: mild, 1·42 (0·28); moderate, 1·47 (0·41); severe, 1·37 (0·49) iu/ml; P = 0·80). Post-partum haemorrhage rates were higher for carriers of severe haemophilia A (13/24; 54·2%) compared to carriers of mild haemophilia A (four of 14; 28·6%).

Bleeding of unknown cause and unclassified bleeding disorders; diagnosis, pathophysiology and management.

Bleeding of unknown cause (BUC), also known as unclassified bleeding disorders (UBD), has been defined as a clear bleeding tendency in the presence of normal haemostatic tests. There are challenges in the diagnosis and management of these patients. BUC/UBD encompasses a heterogenous group of disorders which may include undiagnosed rare monogenic diseases, polygenic reasons for bleeding; and patients without a clear bleeding disorder but with a previous bleeding event. Nevertheless, these patients may have heavy menstrual bleeding or be at risk of bleeding when undergoing surgical procedures, or childbirth; optimizing haemostasis and establishing a mode of inheritance is important to minimize morbidity. The bleeding score has been used to clinically assess and describe these patients, but its value remains uncertain. In addition, accurate distinction between normal and pathological bleeding remains difficult. Several studies have investigated cohorts of these patients using research haemostasis tests, including thrombin generation and fibrinolytic assays, yet no clear characteristics have consistently emerged. Thus far, detailed genetic analysis of these patients has not been fruitful in unravelling the cause of bleeding. There is a need for standardization of diagnosis and management guidelines for these patients. This review gives an overview of this field with some suggestions for future research.

A single centre retrospective study of low dose prophylaxis with extended half-life factor IX for severe haemophilia B.

INTRODUCTION: Extended half-life factor IX concentrates (EHL-FIX) can be administered weekly to prevent bleeding for persons with severe haemophilia B. We report the experience of a large UK haemophilia comprehensive care centre using low dose EHL-FIX for persons with severe haemophilia B. AIM: The low doses used in real world are approximately half of the doses used in clinical trials. We aim to assess the efficacy and safety of low dose EHL-FIX. METHODS: Data from a cohort of 13 patients who were switched from standard half-life factor IX (SHL-FIX) to Alprolix® (mean dose 31.5 IU/kg) and seven patients who switched from standard half-life factor IX to Idelvion® (mean dose 20.2 IU/kg) were included. RESULTS: The median annualized bleeding rate was similar for SHL-FIX (median 3, interquartile range [IQR] 1-5) and EHL-FIX (median 3, IQR 1-5.25). Quality of life scores, measured using the European Quality of Life 5 Dimensions assessment were similar for SHL-FIX (median 0.76, IQR: 0.63-0.84) and EHL-FIX (median 0.79, IQR: 0.58-0.88). CONCLUSION: This study shows that EHL-FIX given at low doses can be effective for prevention of bleeding for persons with severe haemophilia B.

Rebleeding and Mortality After Lower Gastrointestinal Bleeding in Patients Taking Antiplatelets or Anticoagulants.

BACKGROUND & AIMS: Patients who develop lower gastrointestinal bleeding (LGIB) while receiving anticoagulants or anti-platelets have increased severity of bleeding and risk of rebleeding. We compared outcomes of patients receiving antiplatelets, anticoagulants, or direct oral anticoagulants (DOACs) who develop LGIB, as well as the effects of withholding these drugs on their course of bleeding. METHODS: We performed a retrospective study of 2528 consecutive adult patients with LGIB at 143 hospitals in the United Kingdom, from September through December 2015; 917 were taking anticoagulant or antiplatelet drugs and 1218 were taking neither (unexposed). We collected data on demographic features of patients, interventions or medications, outcomes, laboratory test results, and patient readmission until patient death, discharge, or 28 days after admission (whichever came first). Rebleeding was defined as additional transfusion requirements and/or a decrease in hematocrit ≥20% after 24 hrs of clinical stability. Multivariate regression was used to examine the relationship between drug class on presentation with LGIB and rebleeding, mortality, and cardiovascular events. Rates of rebleeding and cardiovascular complications in patients who had these drugs withheld were also analyzed. RESULTS: Patients receiving antiplatelets, but not those receiving warfarin (n = 232) or DOACs (n = 102), had a higher risk of in-hospital rebleeding (monotherapy hazard ratio [HR], 3.57; 95% CI, 1.13-11.28; n = 504 and dual antiplatelet therapy hazard ratio, 5.3; 95% CI, 1.56-18.54; n = 79) compared with the unexposed group. This risk was not lower in patients who received antiplatelets and had the drug withheld for fewer than 5 days, compared to those who continued the drug throughout admission (HR, 0.98; 95% CI, 0.45-2.17) No differences were observed in risk-adjusted mortality or readmission with further bleeding for patients receiving antiplatelets, DOACs, or warfarin. Cardiovascular events were too few to allow meaningful comparison. CONCLUSIONS: In patients with LGIB, antiplatelet drugs, but not warfarin or DOACs, are associated with an increased risk of rebleeding. Withholding antiplatelets during admission does not lead to reduction in rebleeding.

Clinical bleeding and thrombin generation in admissions to critical care with prolonged prothrombin time: an exploratory study.

BACKGROUND: Prolongation of prothrombin time (PT) is often recorded in critical illness, but has limited ability to predict risk of bleeding. This exploratory study was aimed at assessing a role for thrombin generation (TG) to predict bleeding. STUDY DESIGN AND METHODS: TG was measured by calibrated automated thrombography in admissions to intensive care with prolonged PT. Bleeding events were recorded up to Day 5 after enrollment and correlated with results of PT ratio (PTR) and variables of TG. RESULTS: A total of 306 patients were recruited. A total of 101 bleeding events developed in 46 patients during the period of observation. Many patients with prolonged PT had endogenous thrombin potential (ETP), which was within the normal range (120/251 patients, 47.8%) or even elevated (8%). Although some patients had a reduction in ETP or peak thrombin, these were present over a wide range of PTR. There was no suggestion by receiver operating characteristic analysis that variables of conventional TG were sensitive at predicting bleeding. No bleeding events were documented in patients defined as ETP high, despite elevated PTR. CONCLUSION: Future studies need to explore a role for alternatives tests of coagulation in critical illness. Development of TG assays is required to positively identify more patients at increased bleeding risk or to exclude a larger number at low risk and how this relates to subgroups, such as patients with liver disease, and the need for prophylactic plasma transfusion.

Farnesoid X Receptor and Liver X Receptor Ligands Initiate Formation of Coated Platelets.

OBJECTIVES: The liver X receptors (LXRs) and farnesoid X receptor (FXR) have been identified in human platelets. Ligands of these receptors have been shown to have nongenomic inhibitory effects on platelet activation by platelet agonists. This, however, seems contradictory with the platelet hyper-reactivity that is associated with several pathological conditions that are associated with increased circulating levels of molecules that are LXR and FXR ligands, such as hyperlipidemia, type 2 diabetes mellitus, and obesity. APPROACH AND RESULTS: We, therefore, investigated whether ligands for the LXR and FXR receptors were capable of priming platelets to the activated state without stimulation by platelet agonists. Treatment of platelets with ligands for LXR and FXR converted platelets to the procoagulant state, with increases in phosphatidylserine exposure, platelet swelling, reduced membrane integrity, depolarization of the mitochondrial membrane, and microparticle release observed. Additionally, platelets also displayed features associated with coated platelets such as P-selectin exposure, fibrinogen binding, fibrin generation that is supported by increased serine protease activity, and inhibition of integrin αIIbß3. LXR and FXR ligand-induced formation of coated platelets was found to be dependent on both reactive oxygen species and intracellular calcium mobilization, and for FXR ligands, this process was found to be dependent on cyclophilin D. CONCLUSIONS: We conclude that treatment with LXR and FXR ligands initiates coated platelet formation, which is thought to support coagulation but results in desensitization to platelet stimuli through inhibition of αIIbß3 consistent with their ability to inhibit platelet function and stable thrombus formation in vivo.

Transfusion of red blood cells stored for shorter versus longer duration for all conditions.

BACKGROUND: Red blood cell (RBC) transfusion is a common treatment for anaemia in many conditions. The safety and efficacy of transfusing RBC units that have been stored for different durations before a transfusion is a current concern. The duration of storage for a RBC unit can be up to 42 days. If evidence from randomised controlled trials (RCT) were to indicate that clinical outcomes are affected by storage duration, the implications for inventory management and clinical practice would be significant. OBJECTIVES: To assess the effects of using red blood cells (RBCs) stored for a shorter versus a longer duration, or versus RBCs stored for standard practice duration, in people requiring a RBC transfusion. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, PubMed (for epublications), LILACS, Transfusion Evidence Library, Web of Science CPCI-S and four international clinical trial registries on 20 November 2017. SELECTION CRITERIA: We included RCTs that compared transfusion of RBCs of shorter versus longer storage duration, or versus standard practice storage duration. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. MAIN RESULTS: We included 22 trials (42,835 participants) in this review.The GRADE quality of evidence ranged from very low to moderate for our primary outcome of in-hospital and short-term mortality reported at different time points.Transfusion of RBCs of shorter versus longer storage duration Eleven trials (2249 participants) compared transfusion of RBCs of shorter versus longer storage duration. Two trials enrolled low birth weight neonates, two enrolled children with severe anaemia secondary to malaria or sickle cell disease, and eight enrolled adults across a range of clinical settings (intensive care, cardiac surgery, major elective surgery, hospitalised in-patients, haematology outpatients). We judged only two trials to be at low risk of bias across all domains; most trials had an unclear risk for multiple domains.Transfusion of RBCs of shorter versus longer storage duration probably leads to little or no difference in mortality at seven-day follow-up (risk ratio (RR) 1.42, 95% confidence interval (CI) 0.66 to 3.06; 1 trial, 3098 participants; moderate quality evidence) or 30-day follow-up (RR 0.85, 95%CI 0.50 to 1.45; 2 trials, 1121 participants; moderate quality evidence) in adults undergoing major elective cardiac or non-cardiac surgery.For neonates, no studies reported on the primary outcome of in-hospital or short-term mortality. At 40 weeks gestational age, the effect of RBCs of shorter versus longer storage duration on the risk of death was uncertain, as the quality of evidence is very low (RR 0.90, 95% CI 0.41 to 1.85; 1 trial, 52 participants).The effect of RBCs of shorter versus longer storage duration on the risk of death in children with severe anaemia was also uncertain within 24 hours of transfusion (RR 1.50, 95% CI 0.43 to 5.25; 2 trials, 364 participants; very low quality evidence), or at 30-day follow-up (RR 1.40, 95% CI 0.45 to 4.31; 1 trial, 290 participants; low quality evidence).Only one trial, in children with severe anaemia (290 participants), reported adverse transfusion reactions. Only one child in each arm experienced an adverse reaction within 24 hours of transfusion.Transfusion of RBCs of shorter versus standard practice storage duration Eleven trials (40,588 participants) compared transfusion of RBCs of shorter versus standard practice storage duration. Three trials enrolled critically ill term neonates; two of these enrolled very low birth weight neonates. There were no trials in children. Eight trials enrolled critically ill and non-critically ill adults, with most being hospitalised. We judged four trials to be at low risk of bias across all domains with the others having an unclear risk of bias across multiple domains.Transfusion of RBCs of shorter versus standard practice storage duration probably leads to little or no difference in adult in-hospital mortality (RR 1.05, 95% CI 0.97 to 1.14; 4 trials, 25,704 participants; moderate quality evidence), ICU mortality (RR 1.06, 95% CI 0.98 to 1.15; 3 trials, 13,066 participants; moderate quality evidence), or 30-day mortality (RR 1.04, 95% CI 0.96 to 1.13; 4 trials, 7510 participants;moderate quality evidence).Two of the three trials that enrolled neonates reported that there were no adverse transfusion reactions. One trial reported an isolated case of cytomegalovirus infection in participants assigned to the standard practice storage duration group. Two trials in critically ill adults reported data on transfusion reactions: one observed no difference in acute transfusion reactions between arms (RR 0.67, 95% CI 0.19 to 2.36, 2413 participants), but the other observed more febrile nonhaemolytic reactions in the shorter storage duration arm (RR 1.48, 95% CI 1.13 to 1.95, 4919 participants).Trial sequential analysis showed that we may now have sufficient evidence to reject a 5% relative risk increase or decrease of death within 30 days when transfusing RBCs of shorter versus longer storage duration across all patient groups. AUTHORS' CONCLUSIONS: The effect of storage duration on clinically important outcomes has now been investigated in large, high quality RCTs, predominantly in adults. There appears to be no evidence of an effect on mortality that is related to length of storage of transfused RBCs. However, the quality of evidence in neonates and children is low. The current practice in blood banks of using the oldest available RBCs can be continued safely. Additional RCTs are not required, but research using alternative study designs, should focus on particular subgroups (e.g. those requiring multiple RBC units) and on factors affecting RBC quality.

Periprocedural antithrombotic management for lumbar puncture: Association of British Neurologists clinical guideline.

Lumbar puncture (LP) is an important and frequently performed invasive procedure for the diagnosis and management of neurological conditions. There is little in the neurological literature on the topic of periprocedural management of antithrombotics in patients undergoing LP. Current practice is therefore largely extrapolated from guidelines produced by anaesthetic bodies on neuraxial anaesthesia, haematology groups advising on periprocedural management of antiplatelet agents and anticoagulants, and by neuroradiology on imaging-guided spinal procedures. This paper summarises the existing literature on the topic and offers recommendations to guide periprocedural antithrombotic management for LP, based on the consolidation of the best available evidence. ​.

The aspirin story - from willow to wonder drug.

The story of the discovery of aspirin stretches back more than 3500 years to when bark from the willow tree was used as a pain reliever and antipyretic. It involves an Oxfordshire clergyman, scientists at a German dye manufacturer, a Nobel Prize-winning discovery and a series of pivotal clinical trials. Aspirin is now the most commonly used drug in the world. Its role in preventing cardiovascular and cerebrovascular disease has been revolutionary and one of the biggest pharmaceutical success stories of the last century.

Plasma transfusions prior to lumbar punctures and epidural catheters for people with abnormal coagulation.

BACKGROUND: The insertion of a lumbar puncture needle or epidural catheter may be associated with peri- and post-procedural bleeding. People who require this procedure may have disorders of coagulation as a result of their underlying illness, co-morbidities or the effects of treatment. Clinical practice in some institutions is to mitigate the risk of bleeding in these patients by prophylactically transfusing plasma in order to correct clotting factor deficiencies prior to the procedure. However, plasma transfusion is not without risk, and it remains unclear whether this intervention is associated with reduced rates of bleeding or other clinically-meaningful outcomes. OBJECTIVES: To assess the effect of different prophylactic plasma transfusion regimens prior to insertion of a lumbar puncture needle or epidural catheter in people with abnormal coagulation. SEARCH METHODS: We searched for randomised controlled trials (RCTs), non-randomised controlled trials (non-RCT) and controlled before-after studies (CBAs) in CENTRAL (the Cochrane Library 2016, Issue 11), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), the Transfusion Evidence Library (from 1950), and five other electronic databases as well as ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform (ICTRP) for ongoing trials to 9 January 2017. SELECTION CRITERIA: We planned to include RCTs, non-RCTs, and CBAs involving transfusions of plasma given to prevent bleeding in people of any age with a coagulopathy requiring insertion of a lumbar puncture needle or epidural catheter. If identified, we would have excluded uncontrolled studies, cross-sectional studies and case-control studies. We would only have included cluster-RCTs, non-randomised cluster trials, and CBAs with at least two intervention sites and two control sites. In studies with only one intervention or control site, the intervention (or comparison) is completely confounded by study site making it difficult to attribute any observed differences to the intervention rather than to other site-specific variables.We planned to exclude people with haemophilia as they should be treated with the appropriate factor concentrate. We also planned to exclude people on warfarin as guidelines recommend the use of prothrombin complex concentrate for emergency reversal of warfarin. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We identified no completed or ongoing RCTs, non-RCTs, or CBAs. AUTHORS' CONCLUSIONS: There is no evidence from RCTs, non-RCTs, and CBAs to determine whether plasma transfusions are required prior to insertion of a lumbar puncture needle or epidural catheter, and, if plasma transfusions are required, what is the degree of coagulopathy at which they should be given. We would need to design a study with at least 47,030 participants to be able to detect an increase in the number of people who had bleeding after lumbar puncture or epidural anaesthetic from 1 in 1000 to 2 in 1000.

Desmopressin use for minimising perioperative blood transfusion.

BACKGROUND: Blood transfusion is administered during many types of surgery, but its efficacy and safety are increasingly questioned. Evaluation of the efficacy of agents, such as desmopressin (DDAVP; 1-deamino-8-D-arginine-vasopressin), that may reduce perioperative blood loss is needed. OBJECTIVES: To examine the evidence for the efficacy of DDAVP in reducing perioperative blood loss and the need for red cell transfusion in people who do not have inherited bleeding disorders. SEARCH METHODS: We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (2017, issue 3) in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (from 1937), the Transfusion Evidence Library (from 1980), and ongoing trial databases (all searches to 3 April 2017). SELECTION CRITERIA: We included randomised controlled trials comparing DDAVP to placebo or an active comparator (e.g. tranexamic acid, aprotinin) before, during, or immediately after surgery or after invasive procedures in adults or children. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. MAIN RESULTS: We identified 65 completed trials (3874 participants) and four ongoing trials. Of the 65 completed trials, 39 focused on adult cardiac surgery, three on paediatric cardiac surgery, 12 on orthopaedic surgery, two on plastic surgery, and two on vascular surgery; seven studies were conducted in surgery for other conditions. These trials were conducted between 1986 and 2016, and 11 were funded by pharmaceutical companies or by a party with a commercial interest in the outcome of the trial.The GRADE quality of evidence was very low to moderate across all outcomes. No trial reported quality of life. DDAVP versus placebo or no treatmentTrial results showed considerable heterogeneity between surgical settings for total volume of red cells transfused (low-quality evidence) and for total blood loss (very low-quality evidence) due to large differences in baseline blood loss. Consequently, these outcomes were not pooled and were reported in subgroups.Compared with placebo, DDAVP may slightly decrease the total volume of red cells transfused in adult cardiac surgery (mean difference (MD) -0.52 units, 95% confidence interval (CI) -0.96 to -0.08 units; 14 trials, 957 participants), but may lead to little or no difference in orthopaedic surgery (MD -0.02, 95% CI -0.67 to 0.64 units; 6 trials, 303 participants), vascular surgery (MD 0.06, 95% CI -0.60 to 0.73 units; 2 trials, 135 participants), or hepatic surgery (MD -0.47, 95% CI -1.27 to 0.33 units; 1 trial, 59 participants).DDAVP probably leads to little or no difference in the total number of participants transfused with blood (risk ratio (RR) 0.96, 95% CI 0.86 to 1.06; 25 trials; 1806 participants) (moderate-quality evidence).Whether DDAVP decreases total blood loss in adult cardiac surgery (MD -135.24 mL, 95% CI -210.80 mL to -59.68 mL; 22 trials, 1358 participants), orthopaedic surgery (MD -285.76 mL, 95% CI -514.99 mL to -56.53 mL; 5 trials, 241 participants), or vascular surgery (MD -582.00 mL, 95% CI -1264.07 mL to 100.07 mL; 1 trial, 44 participants) is uncertain because the quality of evidence is very low.DDAVP probably leads to little or no difference in all-cause mortality (Peto odds ratio (pOR) 1.09, 95% CI 0.51 to 2.34; 22 trials, 1631 participants) or in thrombotic events (pOR 1.36, 95% CI, 0.85 to 2.16; 29 trials, 1984 participants) (both low-quality evidence). DDAVP versus placebo or no treatment for people with platelet dysfunctionCompared with placebo, DDAVP may lead to a reduction in the total volume of red cells transfused (MD -0.65 units, 95% CI -1.16 to -0.13 units; 6 trials, 388 participants) (low-quality evidence) and in total blood loss (MD -253.93 mL, 95% CI -408.01 mL to -99.85 mL; 7 trials, 422 participants) (low-quality evidence).DDAVP probably leads to little or no difference in the total number of participants receiving a red cell transfusion (RR 0.83, 95% CI 0.66 to 1.04; 5 trials, 258 participants) (moderate-quality evidence).Whether DDAVP leads to a difference in all-cause mortality (pOR 0.72, 95% CI 0.12 to 4.22; 7 trials; 422 participants) or in thrombotic events (pOR 1.58, 95% CI 0.60 to 4.17; 7 trials, 422 participants) is uncertain because the quality of evidence is very low. DDAVP versus tranexamic acidCompared with tranexamic acid, DDAVP may increase the volume of blood transfused (MD 0.6 units, 95% CI 0.09 to 1.11 units; 1 trial, 40 participants) and total blood loss (MD 142.81 mL, 95% CI 79.78 mL to 205.84 mL; 2 trials, 115 participants) (both low-quality evidence).Whether DDAVP increases or decreases the total number of participants transfused with blood is uncertain because the quality of evidence is very low (RR 2.42, 95% CI 1.04 to 5.64; 3 trials, 135 participants).No trial reported all-cause mortality.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 2.92, 95% CI 0.32 to 26.83; 2 trials, 115 participants). DDAVP versus aprotininCompared with aprotinin, DDAVP probably increases the total number of participants transfused with blood (RR 2.41, 95% CI 1.45 to 4.02; 1 trial, 99 participants) (moderate-quality evidence).No trials reported volume of blood transfused or total blood loss and the single trial that included mortality as an outcome reported no deaths.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 0.98, 95% CI 0.06 to 15.89; 2 trials, 152 participants). AUTHORS' CONCLUSIONS: Most of the evidence derived by comparing DDAVP versus placebo was obtained in cardiac surgery, where DDAVP was administered after cardiopulmonary bypass. In adults undergoing cardiac surgery, the reduction in volume of red cells transfused and total blood loss was small and was unlikely to be clinically important. It is less clear whether DDAVP may be of benefit for children and for those undergoing non-cardiac surgery. A key area for researchers is examining the effects of DDAVP for people with platelet dysfunction. Few trials have compared DDAVP versus tranexamic acid or aprotinin; consequently, we are uncertain of the relative efficacy of these interventions.

Alternatives to allogeneic platelet transfusion.

Allogeneic platelet transfusions are widely used for the prevention and treatment of bleeding in thrombocytopenia. Recent evidence suggests platelet transfusions have limited efficacy and are associated with uncertain immunomodulatory risks and concerns about viral or bacterial transmission. Alternatives to transfusion are a well-recognised tenet of Patient Blood Management, but there has been less focus on different strategies to reduce bleeding risk by comparison to platelet transfusion. Direct alternatives to platelet transfusion include agents to stimulate endogenous platelet production (thrombopoietin mimetics), optimising platelet adhesion to endothelium by treating anaemia or increasing von Willebrand factor levels (desmopressin), increasing formation of cross-linked fibrinogen (activated recombinant factor VII, fibrinogen concentrate or recombinant factor XIII), decreasing fibrinolysis (tranexamic acid or epsilon aminocaproic acid) or using artificial or modified platelets (cryopreserved platelets, lyophilised platelets, haemostatic particles, liposomes, engineered nanoparticles or infusible platelet membranes). The evidence base to support the use of these alternatives is variable, but an area of active research. Much of the current randomised controlled trial focus is on evaluation of the use of thrombopoietin mimetics and anti-fibrinolytics. It is also recognised that one alternative strategy to platelet transfusion is choosing not to transfuse at all.