Abstract

The COVID-19 pandemic has major implications for blood transfusion. There are uncertain patterns of demand, and transfusion institutions need to plan for reductions in donations and loss of crucial staff because of sickness and public health restrictions. We systematically searched for relevant studies addressing the transfusion chain-from donor, through collection and processing, to patients-to provide a synthesis of the published literature and guidance during times of potential or actual shortage. A reduction in donor numbers has largely been matched by reductions in demand for transfusion. Contingency planning includes prioritisation policies for patients in the event of predicted shortage. A range of strategies maintain ongoing equitable access to blood for transfusion during the pandemic, in addition to providing new therapies such as convalescent plasma. Sharing experience and developing expert consensus on the basis of evolving publications will help transfusion services and hospitals in countries at different stages in the pandemic.

Abstract

Background: Guidelines to treat anaemia with intravenous (IV) iron have focused on elective surgical patients with little attention paid to those undergoing non-elective/emergency surgery. Whilst these patients may experience poor outcomes because of their presenting illness, observational data suggests that untreated anaemia may also be a contributing factor to poor outcomes. We conducted a systematic review to investigate the safety and efficacy of IV iron in patients undergoing non-elective surgery. Methods: We followed a pre-defined review protocol and included randomised controlled trials (RCTs) in patients undergoing non-elective surgery who received IV iron. Primary outcomes were all-cause infection and mean difference in haemoglobin (Hb) at follow-up. Secondary outcomes included transfusion requirements, hospital length of stay (LOS), health-related quality of life (HRQoL), mortality and adverse events. Results: Three RCTs (605 participants) were included in this systematic review of which two, in both hip fracture (HF) patients, provided data for meta-analysis. Both of these RCTs were at low risk of bias. We found no evidence of a difference in the risk of infection (RR 0.99, 95% CI 0.55 to 1.80, I (2) = 9%) or in the Hb concentration at 'short-term' (≤ 7 days) follow-up (mean difference - 0.32 g/L, 95% CI - 3.28 to 2.64, I (2) = 37%). IV iron did not reduce the risk of requiring a blood transfusion (RR 0.90, 95% CI 0.73 to 1.11, p = 0.46, I (2) = 0%), and we observed no difference in mortality, LOS or adverse events. One RCT reported on HRQoL and found no difference between treatment arms. Conclusion: We found no conclusive evidence of an effect of IV iron on clinically important outcomes in patients undergoing non-elective surgery. Further adequately powered trials to evaluate its benefit in emergency surgical specialties with a high burden of anaemia are warranted. Trial registration: This systematic review was registered on PROSPERO (CRD42018096288).

Abstract

Optimal dose, timing and ratio to red blood cells (RBC) of blood component therapy (fresh frozen plasma [FFP], platelets, cryoprecipitate or fibrinogen concentrate) to reduce morbidity and mortality in critically bleeding patients requiring massive transfusion is unknown. We performed a systematic review for randomized controlled trials (RCT) in MEDLINE, The Cochrane Library, Embase, CINAHL, PubMed the Transfusion Evidence Library and using multiple clinical trials registries to 21 February 2017. Sixteen RCTs were identified: six completed (five in adult trauma patients, one pediatric burn patients) and ten ongoing trials. Of the completed trials: three were feasibility trials, comparing a FFP, platelets and RBC ratio of 1:1:1 to laboratory-guided transfusion practice [n=69], early cryoprecipitate compared to standard practice [n=41], and early fibrinogen concentrate compared to placebo [n=45]; one trial compared the effect of FFP, platelets and RBC ratio of 1:1:1 with 1:1:2 on 24-hour and 30-day mortality [n=680]; one compared whole blood to blood component therapy on 24-hour blood use [n=107]; one compared a FFP to RBC ratio of 1:1 with 1:4 [n=16]. Data from two trials were pooled in a meta-analysis for 28-day mortality because the transfusion ratios achieved were similar. Results from these two trials suggest higher transfusion ratios were associated with transfusion of more FFP and platelets without evidence of significant difference with respect to mortality or morbidity. On the limited evidence available, there is insufficient basis to recommend a 1:1:1 over a 1:1:2 ratio or standard care for adult patients with critical bleeding requiring massive transfusion.

Abstract

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 EXTRACTION 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 (I(2)=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, I(2)=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. REGISTRATION PROSPERO CRD42014014251.Copyright Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Abstract

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. Copyright 2015 Elsevier Inc. All rights reserved.

Abstract

The objective of this systematic review was to identify and analyze the evidence base supporting the 30-minuteand 4-hourrules in transfusion medicine. The 30-minute rule states that red blood cell (RBC) units left out of controlled temperature storage for more than 30 minutes should not be returned to storage for reissue; the 4-hour rule states that transfusion of RBC units should be completed within 4 hours of their removal from controlled temperature storage. Eligible studies were identified from searches (to October 2010) of a range of electronic databases (including The Cochrane Library, MEDLINE, EMBASE, and the National Health Service Blood and Transplant's Transfusion Evidence Library) and contact with transfusion medicine and blood bank experts. Twenty-three studies were identified that measured the quality of the RBC unit (n = 19), bacterial contamination in the RBC unit (n = 4), or both (n = 2) after exposure to greater than 4degreesC +/- 2degreesC from between 20 minutes to 42 days. The overall finding was that temperature exposure did not adversely affect the quality of the RBC units or result in significant bacterial contamination. However, the variation in the temperature of exposure, its duration, the amount of data reported by the individual studies, and the age of the studies (and thus their comparability to current clinical practice) make it difficult to draw significant conclusions. To reliably determine whether these time rulescould be extended without an adverse risk to the RBC unit requires robust, modern studies using multiple combinations of blood, anticoagulant, and additive solutions with defined temperatures and times of exposure. Crown Copyright Copyright 2012. Published by Elsevier Inc. All rights reserved.

Abstract

BACKGROUND AND OBJECTIVES This systematic review was aimed at finding evidence for the safety of blood donation by individuals with treated hypertension or type 2 diabetes. It was undertaken as part of a wider project to re-evaluate exclusion criteria for UK blood donors with a view to increasing eligibility. MATERIALS AND METHODS Searches were undertaken in the Cochrane Library to 2008, MEDLINE (1950 onwards), EMBASE (1974 onwards), CINAHL (1982 onwards), BNID (1994 onwards), the NHSBT SRI Handsearching Database and the Web of Science (all years) to February 2008. Planned analysis was largely descriptive. RESULTS We identified only 16 relevant papers. None of the identified studies directly addressed the review questions and methodological appraisal highlighted a number of deficiencies. However all included papers provided contributory data and the findings were consistent. No study found any evidence of increased risk to homologous (allogeneic) or autologous blood donors with treated hypertension or with raised baseline systolic blood pressure up to 200 mmHg. We found very few data relating to blood donation by diabetic subjects. CONCLUSIONS No identified study indicated that raised baseline blood pressure level, treated hypertension or diabetes was predictive of increased adverse reactions in blood donors but the level of overall evidence was limited. This is the first attempt to systematically review a donor area as part of an approach to change longstanding practice recommendations, and may have implications for other recommendations for changes in donor acceptance criteria. [References: 20]

Abstract

The main treatment for many patients with Myelodysplastic Syndromes (MDS) remains red cell transfusion to attenuate the symptoms of chronic anemia. Fatigue can reduce a patient's health related quality of life (HRQoL), but there is little understanding of the optimal use of transfusions to improve this. A systematic review was performed to identify and appraise publications reporting the use of HRQoL instruments in patients with MDS. A total of 17 separate studies were identified that used 14 HRQoL instruments, but only one MDS disease specific HRQoL instrument (QOL-E) was reported. Two well established HRQoL instruments were most often used in MDS research (variants of the Functional Assessment of Cancer Therapy (FACT) and the European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire (QLQ-C30)). Several common problems were identified in the published literature including a lack of power calculations to detect clinically relevant changes, small sample sizes and significant attrition rates for completion of HRQoL assessments, all of which limit the strength of any conclusions. There is no consensus on the optimal transfusion regimen to improve HRQoL in transfusion-dependent MDS. Future research into HRQoL within MDS is a pressing requirement. Studies should focus on the domains that are of most clinical importance to the patient as well as traditional quantitative changes of hemoglobin concentration.