Harnessing the potential of data-driven strategies to optimise transfusion practice.

No one doubts the significant variation in the practice of transfusion medicine. Common examples are the variability in transfusion thresholds and the use of tranexamic acid for surgery with likely high blood loss despite evidence-based standards. There is a long history of applying different strategies to address this variation, including education, clinical guidelines, audit and feedback, but the effectiveness and cost-effectiveness of these initiatives remains unclear. Advances in computerised decision support systems and the application of novel electronic capabilities offer alternative approaches to improving transfusion practice. In England, the National Institute for Health and Care Research funded a Blood and Transplant Research Unit (BTRU) programme focussing on 'A data-enabled programme of research to improve transfusion practices'. The overarching aim of the BTRU is to accelerate the development of data-driven methods to optimise the use of blood and transfusion alternatives, and to integrate them within routine practice to improve patient outcomes. One particular area of focus is implementation science to address variation in practice.

Major haemorrhage: past, present and future.

Major haemorrhage is a leading cause of morbidity and mortality worldwide. Successful treatment requires early recognition, planned responses, readily available resources (such as blood products) and rapid access to surgery or interventional radiology. Major haemorrhage is often accompanied by volume loss, haemodilution, acidaemia, hypothermia and coagulopathy (factor consumption and fibrinolysis). Management of major haemorrhage over the past decade has evolved to now deliver a 'package' of haemostatic resuscitation including: surgical or radiological control of bleeding; regular monitoring of haemostasis; advanced critical care support; and avoidance of the lethal triad of hypothermia, acidaemia and coagulopathy. Recent trial data advocate for a more personalised approach depending on the clinical scenario. Fresh frozen plasma should be given as early as possible in major trauma in a 1:1 ratio with red blood cells until the results of coagulation tests are available. Tranexamic acid is a cheap, life-saving drug and is advocated in major trauma, postpartum haemorrhage and surgery, but not in patients with gastrointestinal bleeding. Fibrinogen levels should be maintained > 2 g.l-1 in postpartum haemorrhage and > 1.5 g.l-1 in other haemorrhage. Improving outcomes after major traumatic haemorrhage is now driving research to include extending blood-product resuscitation into prehospital care.

The effect of iron deficiency and anaemia on women's health.

Iron deficiency and anaemia are global health problems and major causes of morbidity in women. Current definitions of anaemia in women are historic and have been challenged by recent data from observational studies. Menstrual loss, abnormal uterine bleeding and pregnancy put women at risk of developing iron deficiency which can result in severe fatigue, reduced exercise capacity and poor work performance. Iron deficiency and anaemia during pregnancy are associated with adverse maternal and fetal outcomes, including neurocognitive deficits in children born to iron-deficient mothers. Both iron deficiency and anaemia are common in women undergoing surgery but their association with poor outcomes remains uncertain. The enduring burden of iron deficiency and anaemia in women suggests that current strategies for recognition, prevention and treatment are limited in their utility. Improvements in our understanding of iron homeostasis and the development of new iron preparations, which are better absorbed with fewer side-effects, may improve therapeutic effectiveness of oral iron. Intravenous iron is efficacious for correcting anaemia rapidly but high-quality data on patient-centred outcomes and cost-effectiveness are currently lacking. Many recommendations for the treatment of iron deficiency and anaemia in national guidelines are not supported by high-quality evidence. There is a need for robust epidemiological data and well-designed clinical trials. The latter will require collaborative working between researchers and patients to design studies in ways that incorporate patients' perspectives on the research process and target outcomes that matter to them.

The association of pre-operative anaemia with morbidity and mortality after emergency laparotomy.

Pre-operative anaemia is associated with poor outcomes after elective surgery but its relationship with outcomes after emergency surgery is unclear. We analysed National Emergency Laparotomy Audit data from 1 December 2013 to 30 November 2017, excluding laparotomy for haemorrhage. Anaemia was classified as 'mild' 129-110 g.l-1; 'moderate' 109-80 g.l-1; or 'severe' ≤ 79 g.l-1. The primary outcome was 90-day mortality. Secondary outcomes were 30-day mortality, return to theatre and postoperative hospital stay. The primary outcome was available for 86,763 patients, of whom 45,306 (52%) were anaemic. There were 12,667 (15%) deaths at 90 postoperative days and 9246 (11%) deaths at 30 postoperative days. Anaemia was associated with increased 90-day and 30-day mortality, odds ratio (95%CI): mild, 1.15 (1.09-1.21); moderate, 1.44 (1.36-1.52); and severe, 1.42 (1.24-1.63), p < 0.001 for all; mild, 1.07 (1.00-1.12), p = 0.030; moderate, 1.30 (1.21-1.38), p < 0.001; and severe, 1.22 (1.05-1.43), p = 0.010, respectively. All categories of anaemia were associated with prolonged hospital stay, adjusted coefficient (95%CI): mild, 1.31 (1.01-1.62); moderate, 3.41 (3.04-3.77); severe, 2.80 (1.83-3.77), p < 0.001 for all. Moderate and severe anaemia were associated with increased risk of return to the operating theatre, odds ratio (95%CI): moderate 1.13 (1.06-1.21), p < 0.001; and severe 1.23 (1.06-1.43), p = 0.006. Pre-operative anaemia is common in patients undergoing emergency laparotomy and is associated with increased postoperative mortality and morbidity.

Approaches to understanding and interpreting the risks of red blood cell transfusion in neonates.

In this review, we explore how to assess potential harm related to neonatal transfusion practice. We consider different sources of information, including passive or active surveillance systems such as registries, observational studies, randomised trials and systematic reviews. Future research directions are discussed.

A multicentred study to validate a consensus bleeding assessment tool developed by the biomedical excellence for safer transfusion collaborative for use in patients with haematological malignancy.

BACKGROUND: There continues to be uncertainty about the optimal approach to documenting bleeding data in platelet transfusion trials, with a desire to apply a common assessment tool across all trials. With this in mind, a consensus bleeding assessment tool (BAT) has been developed by the Biomedical Excellence for Safer Transfusion (BEST) collaborative, based on review of data collection forms used in published randomized trials and following content validation with a range of healthcare professionals at seven haematology centres through BEST members. This study aimed to evaluate reliability and reproducibility of the consensus BAT. METHODS: Replicated clinical assessments of bleeding were undertaken by participants with haematological malignancies recruited at four haematology centres in an international, multicentred, observational study. Concordance of repeat assessments was calculated for agreement in site and grade of bleeding observed. RESULTS: Forty patients consented to participate, and 13 trained bleeding assessors collected these data. Bleeding assessments were carried out on 113 separate days. Of all 225 bleeding assessments, 204 were compared for grade concordance, and 160 were compared for site concordance. There was very good grade concordance (83%, 95% confidence interval 74-93%) and good bleeding site concordance (69%, 95% confidence interval 57-79%) in observations of bleeding. Discordance was primarily in relation to assessing skin bleeding. CONCLUSIONS: Alongside a structured training programme, levels of concordance for a consensus BAT were high. Researchers using assessment tools for bleeding need to balance comprehensive data collection against potential loss of accuracy for some types of bleeding, such as skin findings.

Patient blood management, what does this actually mean for neonates and infants?

Patient blood management (PBM) refers to an evidence-based package of care that aims to improve patient outcomes by optimal use of transfusion therapy, including managing anaemia, preventing blood loss and improving anaemia tolerance in surgical and other patients who may need transfusion. In adults, PBM programmes are well established, yet the definition and implementation of PBM in neonates and children lags behind. Neonates and infants are frequently transfused, yet they are often under-represented in transfusion trials. Adult PBM programmes may not be directly applicable to these populations. We review the literature in neonatal (and applicable paediatric) transfusion medicine and propose specific neonatal PBM definitions and elements.

Use of granulocyte transfusions among haematology units in England and North Wales.

OBJECTIVES: To establish the current use of granulocyte transfusions in haematology patients and explore interest in further research. BACKGROUND: Granulocytes may be used for the treatment of severe infection in neutropenic patients or for primary or secondary prophylaxis. Clinical utility of granulocyte transfusions is unclear, and recent studies have demonstrated equivocal outcomes. Pooled granulocytes are the main granulocyte product used in England and Wales, but there are no data on the patterns of use and little consensus on accepted indications. METHODS: A survey was distributed to UK hospitals delivering intensive chemotherapy. Clinical scenarios were posed, with further questions on clinician experience of using granulocytes, availability of the product, barriers to use and interest in further research. RESULTS: The response rate was 57%; 34·9% of all responses were from allogeneic stem cell transplant centres. Paediatric centres comprised 9·5% respondents, and 19% centres had access to apheresis granulocytes. Of respondents, 58·7% had used granulocytes in the last 3 years, 89·2% of whom used granulocytes to treat refractory infection. There was little consensus on use of granulocytes in the given clinical scenarios even when patients clearly met national guideline criteria. Paediatric centres were overall more likely to recommend granulocyte use. The most frequently identified barrier to use of granulocytes was lack of evidence of effect. Of the respondents, 75% indicated a willingness to participate in further research. CONCLUSION: There remains a lack of consistency about use of granulocytes, which is unsurprising given the lack of clinical data to support their efficacy. We did, however, demonstrate a willingness to participate in further research.

Thromboelastography may predict risk of grade 2 bleeding in thrombocytopenic patients.

BACKGROUND AND OBJECTIVES: Platelet count is used as a prophylactic platelet transfusion trigger, although evidence suggests that it is a poor predictor of bleeding. Thus, alternative tests are required. The primary objective of this study was to compare thromboelastography (TEG) parameters on days with and without bleeding symptoms. The secondary objectives were to investigate the relationship between TEG parameters and haematological variables, fever, C-reactive protein (CRP) and platelet transfusion. MATERIALS AND METHODS: This is a prospective, observational pilot study of 13 thrombocytopenic, haemato-oncologic patients, over 17 cycles of chemotherapy. Bleeding assessment was performed daily together with a total platelet count (TPC), reticulated platelet per cent (RPP) and count (RPC), haemoglobin, mean platelet volume, white blood cell count (WBC), CRP and temperature. TEG analyses were performed on weekdays. RESULTS: TEG alpha angle was significantly lower on days with World Health Organization (WHO) grade 2 bleeding than on days without bleeding. Haematologic variables, CRP and platelet transfusion the previous day were associated with the outcome of TEG analysis, but fever was not. CONCLUSION: We found a highly significant correlation between the TEG alpha angle and WHO grade 2 bleeding. This finding suggests that fibrinogen-platelet interactions may affect the bleeding risk in thrombocytopenic patients.

Factors influencing plasma transfusion practices in paediatric intensive care units around the world.

BACKGROUND AND OBJECTIVES: Plasma transfusions are a frequent treatment worldwide, but many studies have reported a wide variation in the indications to transfuse. Recently, an international paediatric study also showed wide variation in frequency in the use of plasma transfusions: 25% of the centres transfused plasma to >5% of their patients, whereas another 25% transfused plasma to <1% of their patients. The objective of this study was to explore the factors associated with different plasma transfusion practices in these centres. MATERIALS AND METHODS: Online survey sent to the local investigators of the 101 participating centres, in February 2016. Four areas were explored: beliefs regarding plasma transfusion, patients' case-mix in each unit, unit's characteristics, and local blood product transfusion policies and processes. RESULTS: The response rate was 82% (83/101). 43% of the respondents believed that plasma transfusions can arrest bleeding, whereas 27% believe that plasma transfusion can prevent bleeding. Centres with the highest plasma transfusion rate were more likely to think that hypovolaemia and mildly abnormal coagulation tests are appropriate indications for plasma transfusions (P = 0·02 and P = 0·04, respectively). Case-mix, centre characteristics or local transfusion services were not identified as significant relevant factors. CONCLUSION: Factors influencing plasma transfusion practices reflect beliefs about indications and the efficacy of transfusion in the prevention and management of bleeding as well as effects on coagulation tests. Educational and other initiatives to target these beliefs should be the focus of research.

Mortality from trauma haemorrhage and opportunities for improvement in transfusion practice.

BACKGROUND: The aim of this study was to describe the prevalence, patterns of blood use and outcomes of major haemorrhage in trauma. METHODS: This was a prospective observational study from 22 hospitals in the UK, including both major trauma centres and smaller trauma units. Eligible patients received at least 4 units of packed red blood cells (PRBCs) in the first 24 h of admission with activation of the massive haemorrhage protocol. Case notes, transfusion charts, blood bank records and copies of prescription/theatre charts were accessed and reviewed centrally. Study outcomes were: use of blood components, critical care during hospital stay, and mortality at 24 h, 30 days and 1 year. Data were used to estimate the national trauma haemorrhage incidence. RESULTS: A total of 442 patients were identified during a median enrolment interval of 20 (range 7-24) months. Based on this, the national incidence of trauma haemorrhage was estimated to be 83 per million. The median age of patients in the study cohort was 38 years and 73·8 per cent were men. The incidence of major haemorrhage increased markedly in patients aged over 65 years. Thirty-six deaths within 24 h of admission occurred within the first 3 h. At 24 h, 79 patients (17·9 per cent) had died, but mortality continued to rise even after discharge. Patients who received a cumulative ratio of fresh frozen plasma to PRBCs of at least 1 : 2 had lower rates of death than those who received a lower ratio. There were delays in administration of blood. Platelets and cryoprecipitate were either not given, or transfused well after initial resuscitation. CONCLUSION: There is a high burden of trauma haemorrhage that affects all age groups. Research is required to understand the reasons for death after the first 24 h and barriers to timely transfusion support.

Spotlight on platelets: summary of BBTS combined special interest group autumn meeting, November 2015.

This conference first addressed aspects of component quality, highlighting the role of pathogen inactivation, the role of PAS or plasma in prolonging platelet viability and acceptable storage deviations. A series of talks on the medical use of platelets covered the role of platelet transfusion in preventing intracranial haemorrhage, platelet prophylaxis in haematological patients and the new trial of the HLA Matchmaker programme to provide epitope-matched platelets. The session on the surgical use of platelets considered the role of platelet transfusions in patients on anti-platelet agents, major trauma and interventional procedures and also the scope for tests of platelet function to direct therapy. The conference concluded with a panel discussion highlighting key areas of general interest, including the clinical use of platelets and near patient platelet function tests.

Evidence and triggers for the transfusion of blood and blood products.

Allogeneic red cell transfusion is a commonly used treatment to improve the oxygen carrying capacity of blood during the peri-operative period. Increasing arterial oxygen content by increasing haemoglobin does not necessarily increase tissue oxygen delivery or uptake. Although the evidence-base for red cell transfusion practice is incomplete, randomised studies across a range of clinical settings, including surgery, consistently support the restrictive use of red cells, with no evidence of benefit for maintaining patients at higher haemoglobin thresholds (liberal strategy). A recent meta-analysis of 7593 patients concluded that a restrictive transfusion strategy was associated with a reduced risk of healthcare-associated infections (pneumonia, mediastinitis, wound infection, sepsis) when compared with a liberal transfusion strategy. The degree to which the optimal haemoglobin concentration or transfusion trigger should be modified for patients with additional specific risk factors (e.g. ischaemic heart disease), remains less clear and requires further research. Although most clinical practice guidelines recommend restrictive use of red cells, and many blood transfusion services have seen marked falls in overall usage of red cells, the use of other blood components such as fresh frozen plasma, platelets, and cryoprecipitate has risen. In clinical practice, administration of fresh frozen plasma is usually guided by laboratory tests of coagulation, mainly prothrombin time, international normalised ratio and activated partial thromboplastin time, but the predictive value of these tests to predict bleeding is poor.

Factors associated with prophylactic plasma transfusion before vascular catheterization in non-bleeding critically ill adults with prolonged prothrombin time: a case-control study.

BACKGROUND: Fresh-frozen plasma (FFP) is widely used in critically ill patients, despite a weak evidence base. Factors that influence the decision to transfuse FFP before intravascular catheter insertion are poorly described. METHODS: We undertook a case-controlled study based on a prospective cohort study of 1923 admissions to 29 intensive care units in the UK. Non-bleeding patients with an international normalized ratio (INR) ≥1.5 who underwent intravascular catheterization, but no other invasive procedure, were identified. We compared patient characteristics, illness-related factors, and biochemical and haematological variables between patients who did or did not receive pre-procedural FFP. RESULTS: One hundred and eighty-six patients fulfilled the criteria; 26 received FFP during the 24 h before line insertion (cases) and 160 did not (controls). Factors associated with greater use of prophylactic FFP by clinicians were pre-existing chronic liver disease (P=0.01), higher serum bilirubin before procedure (P=0.01), lower platelet count (P=0.01), higher activated partial thromboplastin time (P=0.001), lower fibrinogen (P=0.01), and concurrent red cell transfusion despite the absence of bleeding (P=0.001). There was no difference in pre-procedural INR [median (1st, 3rd quartile) cases: 1.95 (1.85, 2.6); controls 1.8 (1.6, 2.3); P=0.19]. The mean FFP dose was 11.1 ml kg(-1) (sd 5.7 ml kg(-1)); 53.8% of cases were transfused <10 ml kg(-1). CONCLUSIONS: Chronic liver disease and more abnormal coagulation tests were associated with greater probability of pre-procedural FFP administration before vascular catheterization, whereas the severity of prothrombin time prolongation alone was not. FFP was more likely to be administered when red cells were also transfused, even in the absence of bleeding.

Platelet transfusions for patients with haematological malignancies: who needs them?

The goal of platelet transfusions is to prevent severe and life-threatening bleeding in patients with thrombocytopenia. This aim needs to be balanced against the risks associated with platelet transfusions as well as the challenge of maintaining an adequate supply. This review summarizes the recent evidence regarding the clinical use of platelet transfusions in haematology patients, concentrating on the topics that still continue to provoke debate. These include the optimal dose for platelet transfusions and the relative safety of a 'therapeutic only' platelet transfusion strategy compared to the use of prophylactic platelet transfusions. The type of platelet product has been the subject of two recent systematic reviews. The results of these reviews will be discussed as well as their implications for current practice.

Transfusion practice and safety: current status and possibilities for improvement.

Audits of practice and incident reporting, most notably to national haemovigilance schemes, indicate that poor hospital transfusion practice is frequent and occasionally results in catastrophic consequences for patients. Improvements in practice are needed and depend on a combined approach including a better understanding of the causes of errors; a reduction in the complexity of routine procedures taking advantage of new technology systems, which enforce agreed guidelines and policies; the setting and regular monitoring of performance standards for key aspects of the hospital transfusion process, improved organisation of transfusion in hospitals and staff training; and further research on the safe and effective use of blood and alternatives to donor blood. There needs to be a greater recognition that 'transfusion safety' applies to the hospital transfusion process as well as the contents of blood bags and that resources need to be provided for the improvement of transfusion safety and management in hospitals commensurate to their importance.

A national clinical scenario-based survey of clinicians' attitudes towards fresh frozen plasma transfusion for critically ill patients.

BACKGROUND: It is known that 20-30% of fresh frozen plasma (FFP) is used in intensive care units (ICUs), but little is known about variations in decision making between clinicians in relation to coagulopathy management. Our aim was to describe ICU clinicians' beliefs and practice in relation to FFP treatment of non-bleeding coagulopathic critically ill patients. METHODS: Two patient-based scenarios were developed and sent to 2700 members of two UK intensive care professional societies. Scenario 1 was a non-bleeding septic patient with coagulopathy; scenario 2 was a non-bleeding critically ill patient with hepatic cirrhosis and coagulopathy. Responses were sought in relation to FFP prophylaxis, and prior to central venous cannulation. A supplementary question asked clinicians' view of prophylaxis in relation to other ICU procedures. RESULTS: Two-thousand-and-seven-hundred clinicians were surveyed from whom 601 responses were received (22·3% response rate). For scenario 1 52% of respondents stated that they would never routinely administer prophylactic FFP, but this decreased to 9% when central venous cannulation was planned (P < 0·01). There was wide variation in the 'trigger' INR (international normalised ratio) value used prior to central vein cannulation, the most common range being 2·0-2·4. For scenario 2, responses were very similar. More than 80% of clinicians stated that they would routinely treat coagulopathy prior to lumbar puncture, epidural catheterisation, intracranial pressure monitoring and tracheostomy; and 54% prior to chest drain insertion. CONCLUSION: Our survey demonstrated a wide range of responses consistent with important variations in clinical practice and substantial clinical uncertainty in relation to FFP treatment for non-bleeding ICU patients.