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Jairath V.,Systematic Review Initiative
Cochrane database of systematic reviews (Online) | Year: 2010

BACKGROUND: Upper gastrointestinal haemorrhage affects 50 to 150 per 100,000 adults per year, with a high mortality. Red blood cell transfusions are frequently given, but their impact on rebleeding rates and mortality is unknown. OBJECTIVES: To assess the effects of red blood cell (RBC) transfusion in adults with upper gastrointestinal haemorrhage. SEARCH STRATEGY: For this update, we re-ran the initial search strategies from the last issue/month searched until March 2010.We previously searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register to February 2008, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, issue 1), MEDLINE (1950 to February 2008), EMBASE (1974 to February 2008), the Systematic Review Initiative database of randomised controlled trials (RCTs), haematology and gastroenterology conference proceedings, and reference lists of articles. SELECTION CRITERIA: Randomised and quasi-randomised studies comparing RBC transfusion and standard care with other intravenous fluid and standard care regimens in haemodynamically stable and haemodynamically unstable adults with upper gastrointestinal haemorrhage. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. MAIN RESULTS: Three trials involving 126 patients were included, with complete data available for 93 patients. The participants were heterogeneous, none of the three studies examined exactly the same interventions or measured the same outcomes. Only two trials reported mortality data and the summary relative risk for mortality of the intervention was 5.4 (95% CI 0.27 to 107.09). One trial reported increased coagulation times in the transfused group, and reported these patients to have increased rates of rebleeding. None of the studies reported adverse events directly related to RBC transfusion. Methodological deficiencies, including allocation concealment, generation of random sequences and blinding, simply compound the uncertainty surrounding analysis. None of the studies were appropriately powered and in the largest study fewer than half the participants were included in the final analysis.One RCT of restrictive versus liberal RBC transfusion aims to recruit 860 patients but has yet to be completed. AUTHORS' CONCLUSIONS: There were more deaths and more rebleeding in the transfusion arms of the combined studies, but the small numbers of participants and large volume of missing data limit the significance of the findings. The studies in this review do not provide useful data regarding outcomes following red blood cell transfusion for acute upper gastrointestinal haemorrhage. They appear to exclude large survival benefit. Large, well-concealed RCTs of sufficient power are urgently needed. Source


Parker J.A.,John Radcliffe Hospital | Barroso F.,Barts and London Hospitals NHS Trust and NHS Blood and Transplant | Stanworth S.J.,University of Oxford | Spiby H.,University of Nottingham | And 4 more authors.
BMC Pregnancy and Childbirth | Year: 2012

Background: Anaemia, in particular due to iron deficiency, is common in pregnancy with associated negative outcomes for mother and infant. However, there is evidence of significant variation in management. The objectives of this review of systematic reviews were to analyse and summarise the evidence base, identify gaps in the evidence and develop a research agenda for this important component of maternity care.Methods: Multiple databases were searched, including MEDLINE, EMBASE and The Cochrane Library. All systematic reviews relating to interventions to prevent and treat anaemia in the antenatal and postnatal period were eligible. Two reviewers independently assessed data inclusion, extraction and quality of methodology.Results: 27 reviews were included, all reporting on the prevention and treatment of anaemia in the antenatal (n = 24) and postnatal periods (n = 3). Using AMSTAR as the assessment tool for methodological quality, only 12 of the 27 were rated as high quality reviews. The greatest number of reviews covered antenatal nutritional supplementation for the prevention of anaemia (n = 19). Iron supplementation was the most extensively researched, but with ongoing uncertainty about optimal dose and regimen. Few identified reviews addressed anaemia management post-partum or correlations between laboratory and clinical outcomes, and no reviews reported on clinical symptoms of anaemia.Conclusions: The review highlights evidence gaps including the management of anaemia in the postnatal period, screening for anaemia, and optimal interventions for treatment. Research priorities include developing standardised approaches to reporting of laboratory outcomes, and information on clinical outcomes relevant to the experiences of pregnant women. © 2012 Parker et al.; licensee BioMed Central Ltd. Source


Hibbs S.P.,University of Oxford | Nielsen N.D.,University of Maryland Baltimore County | Brunskill S.,Systematic Review Initiative | Doree C.,Systematic Review Initiative | And 3 more authors.
Transfusion Medicine Reviews | Year: 2015

Decision support systems (DSSs) provide clinicians with tailored treatment recommendations by combining individual patient information and local guidelines. The objective of this systematic review was to assess the effects of electronic DSS on blood product ordering practices. Eligible studies were identified from searches of MEDLINE, Embase, CINAHL, The Cochrane Library, PubMed, and the Transfusion Evidence Library from January 2000 to April 2014. Of these, 23 articles were eligible, resulting in the inclusion of 20 independent studies in this systematic review. There was a significant variation in study population, the type of DSS used, and outcome reporting. All but one study used a before-after design without any element of randomization. Overall, there is good evidence that implementation of a DSS improves red blood cell usage. The effect of a DSS on plasma, platelets, and cryoprecipitate usage is less clear probably because fewer studies have been conducted focusing on these products. In addition, the introduction of a DSS resulted in cost savings in the 7 studies that reported financial outcomes. Patient outcomes were generally not studied in detail, and there were few data on the sustainability of the effect of DSS. Further data are needed to assess the effect of a DSS on blood products other than red blood cell, and future studies should standardize reporting of outcomes. © 2015 Elsevier Inc. Source


Smith G.A.,Barnet and Chase Farm Hospitals NHS Trust | Fisher S.A.,Systematic Review Initiative | Doree C.,Systematic Review Initiative | Roberts D.J.,Systematic Review Initiative
Transfusion Medicine | Year: 2013

Background/Objectives: Blood donors attending a donation session may be deemed ineligible to donate blood due to a failure to meet low haemoglobin (Hb) thresholds. Several studies have identified factors associated with a donor falling below these Hb thresholds. A review of these factors will inform future prospective studies and form the basis for predictive models of deferral due to low Hb. Materials/Methods: Studies were identified by searching MEDLINE, EMBASE, The Cochrane Library and the WHO International Clinical Trials Registry from 1980 to September 2012. Demographic data, donor history, haematological/biological factors and the primary outcome of deferral due to low Hb were extracted. Analyses were descriptive and quantitative; pooled odds ratios (ORs) were obtained by meta-analysis. Results: Fifty-five studies met the inclusion criteria. A consistently higher rate of low Hb deferral was reported in females compared with males; meta-analysis showed a significantly greater risk of deferral due to low Hb in females compared with males in studies with universal Hb thresholds for males and females (OR 14·91, 95% confidence interval (CI) 12·82-17·34) and in studies with sex-specific Hb thresholds (OR 8·19, 95% CI 4·88-13·74). Greater rates of deferral due to low Hb were also associated with increasing age, higher ambient temperature, low body weight, shorter inter-donation interval and in donors of Hispanic or African descent. Conclusion: This work will help to define the criteria that should be considered in any large scale study of blood donor deferral, especially those that measure or aim to change failure to meet low Hb thresholds. © 2013 The Authors. Transfusion Medicine © 2013 British Blood Transfusion Society. Source


Docherty A.B.,University of Edinburgh | Docherty A.B.,Royal Infirmary | O'Donnell R.,Royal Infirmary | Brunskill S.,Systematic Review Initiative | And 10 more authors.
BMJ (Online) | Year: 2016

OBJECTIVE: To compare patient outcomes of restrictive versus liberal blood transfusion strategies in patients with cardiovascular disease not undergoing cardiac surgery. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Randomised controlled trials involving a threshold for red blood cell transfusion in hospital. We searched (to 2 November 2015) CENTRAL, Medline, Embase, CINAHL, PubMed, LILACS, NHSBT Transfusion Evidence Library, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, ISRCTN Register, and EU Clinical Trials Register. Authors were contacted for data whenever possible. TRIAL SELECTION: Published and unpublished randomised controlled trials comparing a restrictive with liberal transfusion threshold and that included patients with cardiovascular disease. DATA EXTRA CTION AND SYNTHESIS: Data extraction was completed in duplicate. Risk of bias was assessed using Cochrane methods. Relative risk ratios with 95% confidence intervals were presented in all meta-analyses. Mantel-Haenszel random effects models were used to pool risk ratios. MAIN OUTCOME MEASURES: 30 day mortality, and cardiovascular events. RESULTS: 41 trials were identified; of these, seven included data on patients with cardiovascular disease. Data from a further four trials enrolling patients with cardiovascular disease were obtained from the authors. In total, 11 trials enrolling patients with cardiovascular disease (n=3033) were included for meta-analysis (restrictive transfusion, n=1514 patients; liberal transfusion, n=1519). The pooled risk ratio for the association between transfusion thresholds and 30 day mortality was 1.15 (95% confidence interval 0.88 to 1.50, P=0.50), with little heterogeneity (I2=14%). The risk of acute coronary syndrome in patients managed with restrictive compared with liberal transfusion was increased (nine trials; risk ratio 1.78, 95% confidence interval 1.18 to 2.70, P=0.01, I2=0%). CONCLUSIONS: The results show that it may not be safe to use a restrictive transfusion threshold of less than 80 g/L in patients with ongoing acute coronary syndrome or chronic cardiovascular disease. Effects on mortality and other outcomes are uncertain. These data support the use of a more liberal transfusion threshold (>80 g/L) for patients with both acute and chronic cardiovascular disease until adequately powered high quality randomised trials have been undertaken in patients with cardiovascular disease. Source

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