Restrictive Transfusion Group Research Articles

Red blood cell transfusion in neurocritical patients: a systematic review and meta-analysis

BackgroundAnemia can lead to secondary brain damage by reducing arterial oxygen content and brain oxygen supply. Patients with acute brain injury have impaired self-regulation. Brain hypoxia may also occur even in mild anemia. Red blood cell (RBC) transfusion is associated with increased postoperative complications, poor neurological recovery, and mortality in critically ill neurologic patients. Balancing the risks of anemia and red blood cell transfusion-associated adverse effects is challenging in neurocritical settings.MethodsWe searched the Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and MEDLINE (PubMed) from inception to January 31, 2024. We included all randomized controlled trials (RCTs) assessing liberal versus restrictive RBC transfusion strategies in neurocritical patients. We included all relevant studies published in English. The primary outcome was mortality at intensive care unit (ICU), discharge, and six months.ResultsOf 5195 records retrieved, 84 full-text articles were reviewed, and five eligible studies were included. There was no significant difference between the restrictive and liberal transfusion groups in ICU mortality (RR: 2.53, 95% CI: 0.53 to 12.13), in-hospital mortality (RR: 2.34, 95% CI: 0.50 to 11.00), mortality at six months (RR: 1.42, 95% CI: 0.42 to 4.78) and long-term mortality (RR: 1.22, 95% CI: 0.64 to 2.33). The occurrence of neurological adverse events and most major non-neurological complications was similar in the two groups. The incidence of deep venous thrombosis was lower in the restrictive strategy group (RR: 0.41, 95% CI: 0.18 to 0.91).ConclusionsDue to the small sample size of current studies, the evidence is insufficiently robust to confirm definitive conclusions for neurocritical patients. Therefore, further investigation is encouraged to define appropriate RBC transfusion thresholds in the neurocritical setting.

Ultra-restrictive red blood cell transfusion strategies in extensively burned patients

In recent years, due to the shortage of blood products, some extensive burn patients were forced to adopt an “ultra-restrictive” transfusion strategy, in which the hemoglobin levels of RBC transfusion thresholds were < 7 g/dl or even < 6 g/dl. This study investigated the prognostic impacts of ultra-restrictive RBC transfusion in extensive burn patients. This retrospective multicenter cohort study recruited extensive burns (total body surface area ≥ 50%) from three hospitals in Eastern China between 1 January 2016 and 30 June 2022. Patients were divided into an ultra-restrictive transfusion group and a restrictive transfusion group depending on whether they received timely RBC transfusion at a hemoglobin level < 7 g/dl. 1:1 ratio propensity score matching (PSM) was performed to balance selection bias. Modified Poisson regression and linear regression were conducted for sensitive analysis. Subsequently, according to whether they received timely RBC transfusion at a hemoglobin level < 6 g/dl, patients in the ultra-restrictive transfusion group were divided into < 6 g/dl group and 6–7 g/dl group to further compare the prognostic outcomes. 271 eligible patients with extensive burns were included, of whom 107 patients were in the ultra-restrictive transfusion group and 164 patients were in the restrictive transfusion group. The ultra-restrictive transfusion group had a significantly lower RBC transfusion volume than the restrictive transfusion group (11.5 [5.5, 21.5] vs 17.3 [9.0, 32.5] units, p = 0.004). There were no significant differences between the two groups in terms of in-hospital mortality, risk of infection, hospital length of stay, and wound healing time after PSM or multivariate adjustment (p > 0.05). Among the ultra-restrictive transfusion group, patients with RBC transfusion threshold < 6 g/dl had a significantly higher hospital mortality than 6–7 g/dl (53.1% vs 21.3%, p = 0.001). For extensive burn patients, no significant adverse effects of ultra-restrictive RBC transfusion were found in this study. When the blood supply is tight, it is acceptable to adopt an RBC transfusion threshold of < 7 g/dL but not < 6 g/dL.

Comparison of restrictive and liberal red blood cell suspension transfusion and analysis of influencing factors on prognosis of premature infants.

To investigate the influence of restrictive and liberal red blood cell suspension (RBCs) transfusions on the prognosis of premature infants and to analyze the influencing factors to provide a reference for the transfusion strategy of preterm infants. Retrospective analysis was conducted on 85 cases of anemic premature infants treated in our center, including 63 cases in the restrictive transfusion group and 22 in the liberal transfusion group. RBCs transfusions were effective in both groups, and there were no statistically significant differences in post-transfusion hemoglobin and hematocrit between the two groups (P>0.05). The outcome events: the duration of ventilatory support was statistically prolonger in the restrictive group compared with the liberal group (P<0.001); however, the differences in mortality, the increased weight before discharge, and length of stay in the hospital within the two groups were not statistically significant (P=0.237, 0.36 and 0.771, respectively). Univariate survival analysis showed that age, birth weight, Apgar 1 min and Apgar 10 min scores were the influencing factors for death, with P values of 0.035, 0.004, <0.001, and 0.013, respectively; COX regression analysis showed that Apgar 1 min score was an independent factor of the survival time of preterm infants (P=0.002). Compared with the restrictive transfusion group, liberal transfusion patients presented a shorter duration of ventilatory support, which is more beneficial to the prognosis of premature infants.

Transfusion trigger after operations in high cardiac risk patients (TOP) trial protocol. Protocol for a multicenter randomized controlled transfusion strategy trial

BackgroundThere is substantial uncertainty regarding the effects of restrictive postoperative transfusion among patients who have underlying cardiovascular disease. The TOP Trial's objective is to compare adverse outcomes between liberal and restrictive transfusion strategies in patients undergoing vascular and general surgery operations, and with a high risk of postoperative cardiac events. MethodsA two-arm, single-blinded, randomized controlled superiority trial will be used across 15 Veterans Affairs hospitals with expected enrollment of 1520 participants. Postoperative transfusions in the liberal arm commence when Hb is <10 g/ dL and continue until Hb is greater than or equal to 10 g/dL. In the restrictive arm, transfusions begin when Hb is <7 g/dL and continue until Hb is greater than or equal to 7 g/dL. Study duration is estimated to be 5 years including a 3-month start-up period and 4 years of recruitment. Each randomized participant will be followed for 90 days after randomization with a mortality assessment at 1 year. ResultsThe primary outcome is a composite endpoint of all-cause mortality, myocardial infarction (MI), coronary revascularization, acute renal failure, or stroke occurring up to 90-days after randomization. Events rates will be compared between restrictive and liberal transfusion groups. ConclusionsThe TOP Trial is uniquely positioned to provide high quality evidence comparing transfusion strategies among patients with high cardiac risk. Results will clarify the effect of postoperative transfusion strategies on adverse outcomes and inform postoperative management algorithms.TRIAL REGISTRATION: http://clinicaltrials.gov identifier: NCT03229941

Comparative efficacy and safety of restrictive versus liberal transfusion thresholds in anemic preterm infants: a meta-analysis of 12 randomized controlled trials

The comparative efficacy and safety of restrictive with liberal transfusion thresholds remain controversial in anemic preterm infants. This meta-analysis aimed to compare the efficacy and safety of these two transfusion thresholds for anemic preterm infants. We searched PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) for relevant randomized controlled trials (RCTs) comparing restrictive with liberal transfusion thresholds in anemic preterm infants through April 30, 2022. Two independent investigators screened literature, extracted data, and appraised the methodological quality of eligible studies. Meta-analysis was conducted using RevMan version 5.3.5. Twelve RCTs with 4380 preterm infants were included. Liberal transfusion threshold significantly increased the level of hemoglobin after transfusion (mean difference (MD): −10.03; 95% confidence interval (CI): −15.98 to −4.08; p=0.001; I2=94%) and hematocrit (MD: −3.62; 95%CI: −6.78 to −0.46; p=0.02; I2=80%) compared with restrictive transfusion. Infants’ age at first transfusion in restrictive transfusion group was higher than that of infants in liberal transfusion group (MD: 5.08; 95%CI: 2.27 to7.89; p=0.004; I2=54%); however, restrictive transfusion was associated with more time on supplemental oxygen (MD: 3.56; 95%CI: 1.93 to 5.18; p<0.001; I2=62%) and ventilator or CPAP (MD: 3.31; 95%CI: 1.42 to 5.20; p=0.006; I2=75%). For the remaining outcomes, two transfusion strategies were comparable. Furthermore, a series of sensitivity analyses confirmed the robustness of the level of hemoglobin after transfusion, age at first transfusion, time on ventilator or CPAP, and safety outcomes. Evidence with substantial heterogeneity indicates that liberal and restrictive transfusion thresholds are effective and safe blood cell transfusion strategies in anemic preterm infants, but the liberal strategy may be more effective in shortening the length of necessary respiratory support.

Transfusion thresholds for guiding red blood cell transfusion.

Transfusion thresholds for guiding red blood cell transfusion.

Restrictive vs. Liberal Red Blood Cell Transfusion Strategy in Patients With Acute Myocardial Infarction and Anemia: A Systematic Review and Meta-Analysis

Objective: Anemia is frequent in patients with acute myocardial infarction (AMI), and the optimal red blood cell transfusion strategy for AMI patients with anemia is still controversial. We aimed to compare the efficacy of restrictive and liberal red cell transfusion strategies in AMI patients with anemia.Methods: We systematically searched PubMed, EMBASE, Web of Science, Cochrane Library, and Clinicaltrials.gov, from their inception until March 2021. Studies designed to compare the efficacy between restrictive and liberal red blood cell transfusion strategies in patients with AMI were included. The primary outcome was all-cause mortality, including overall mortality, in-hospital or follow-up mortality. Risk ratios (RR) with 95% confidence intervals (CI) were presented and pooled by random-effects models.Results: The search yielded a total of 6,630 participants in six studies. A total of 2,008 patients received restrictive red blood cell transfusion while 4,622 patients were given liberal red blood cell transfusion. No difference was found in overall mortality and follow-up mortality between restrictive and liberal transfusion groups (RR = 1.07, 95% CI = 0.82–1.40, P = 0.62; RR = 0.89, 95% CI = 0.56–1.42, P = 0.62). However, restrictive transfusion tended to have a higher risk of in-hospital mortality compared with liberal transfusion (RR = 1.22, 95% CI = 1.00–1.50, P = 0.05). No secondary outcomes, including follow-up reinfarction, stroke, and acute heart failure, differed significantly between the two groups. In addition, subgroup analysis showed no differences in overall mortality between the two groups based on sample size and design.Conclusion: Restrictive and liberal red blood cell transfusion have a similar effect on overall mortality and follow-up mortality in AMI patients with anemia. However, restrictive transfusion tended to have a higher risk of in-hospital mortality compared with liberal transfusion. The findings suggest that transfusion strategy should be further evaluated in future studies.

Effect of a Restrictive vs Liberal Blood Transfusion Strategy on Major Cardiovascular Events Among Patients With Acute Myocardial Infarction and Anemia

The optimal transfusion strategy in patients with acute myocardial infarction and anemia is unclear. To determine whether a restrictive transfusion strategy would be clinically noninferior to a liberal strategy. Open-label, noninferiority, randomized trial conducted in 35 hospitals in France and Spain including 668 patients with myocardial infarction and hemoglobin level between 7 and 10 g/dL. Enrollment could be considered at any time during the index admission for myocardial infarction. The first participant was enrolled in March 2016 and the last was enrolled in September 2019. The final 30-day follow-up was accrued in November 2019. Patients were randomly assigned to undergo a restrictive (transfusion triggered by hemoglobin ≤8; n = 342) or a liberal (transfusion triggered by hemoglobin ≤10 g/dL; n = 324) transfusion strategy. The primary clinical outcome was major adverse cardiovascular events (MACE; composite of all-cause death, stroke, recurrent myocardial infarction, or emergency revascularization prompted by ischemia) at 30 days. Noninferiority required that the upper bound of the 1-sided 97.5% CI for the relative risk of the primary outcome be less than 1.25. The secondary outcomes included the individual components of the primary outcome. Among 668 patients who were randomized, 666 patients (median [interquartile range] age, 77 [69-84] years; 281 [42.2%] women) completed the 30-day follow-up, including 342 in the restrictive transfusion group (122 [35.7%] received transfusion; 342 total units of packed red blood cells transfused) and 324 in the liberal transfusion group (323 [99.7%] received transfusion; 758 total units transfused). At 30 days, MACE occurred in 36 patients (11.0% [95% CI, 7.5%-14.6%]) in the restrictive group and in 45 patients (14.0% [95% CI, 10.0%-17.9%]) in the liberal group (difference, -3.0% [95% CI, -8.4% to 2.4%]). The relative risk of the primary outcome was 0.79 (1-sided 97.5% CI, 0.00-1.19), meeting the prespecified noninferiority criterion. In the restrictive vs liberal group, all-cause death occurred in 5.6% vs 7.7% of patients, recurrent myocardial infarction occurred in 2.1% vs 3.1%, emergency revascularization prompted by ischemia occurred in 1.5% vs 1.9%, and nonfatal ischemic stroke occurred in 0.6% of patients in both groups. Among patients with acute myocardial infarction and anemia, a restrictive compared with a liberal transfusion strategy resulted in a noninferior rate of MACE after 30 days. However, the CI included what may be a clinically important harm. ClinicalTrials.gov Identifier: NCT02648113.

Systematic reviews and meta-analyses comparing mortality in restrictive and liberal haemoglobin thresholds for red cell transfusion: an overview of systematic reviews

BackgroundThere are no overviews of systematic reviews investigating haemoglobin thresholds for transfusion. This is important as the literature on transfusion thresholds has grown considerably in recent years. Our aim was to synthesise evidence from systematic reviews and meta-analyses of the effects of restrictive and liberal transfusion strategies on mortality.MethodsThis was a systematic review of systematic reviews (overview). We searched MEDLINE, Embase, Web of Science Core Collection, PubMed, Google Scholar, and the Joanna Briggs Institute EBP Database, from 2008 to 2018. We included systematic reviews and meta-analyses of randomised controlled trials comparing mortality in patients assigned to red cell transfusion strategies based on haemoglobin thresholds. Two independent reviewers extracted data and assessed methodological quality. We assessed the methodological quality of included reviews using AMSTAR 2 and the quality of evidence pooled using an algorithm to assign GRADE levels.ResultsWe included 19 systematic reviews reporting 33 meta-analyses of mortality outcomes from 53 unique randomised controlled trials. Of the 33 meta-analyses, one was graded as high quality, 15 were moderate, and 17 were low. Of the meta-analyses presenting high- to moderate-quality evidence, 12 (75.0%) reported no statistically significant difference in mortality between restrictive and liberal transfusion groups and four (25.0%) reported significantly lower mortality for patients assigned to a restrictive transfusion strategy. We found few systematic reviews addressed clinical differences between included studies: variation was observed in haemoglobin threshold concentrations, the absolute between group difference in haemoglobin threshold concentration, time to randomisation (resulting in transfusions administered prior to randomisation), and transfusion dosing regimens.ConclusionsMeta-analyses graded as high to moderate quality indicate that in most patient populations no difference in mortality exists between patients assigned to a restrictive or liberal transfusion strategy.Trial registrationPROSPERO CRD42019120503

Reducing the red blood cell transfusion threshold from 8·0 g/dl to 7·0 g/dl in acute myeloid leukaemia patients undergoing induction chemotherapy reduces transfusion rates without adversely affecting patient outcome.

Red blood cell (RBC) transfusions are needed by almost every acute myeloid leukaemia (AML) patient undergoing induction chemotherapy and constitute a cornerstone in supportive measures for cancer patients in general. Randomized controlled trials have shown non-inferiority or even superiority of restrictive transfusion guidelines over liberal transfusion guidelines in specific clinical situations outside of medical oncology. In this study, we analysed whether more restrictive RBC transfusion reduces blood use without affecting hard outcomes. A total of 352 AML patients diagnosed between 2007 and 2018 and undergoing intensive induction chemotherapy were included in this retrospective analysis. In the less restrictive transfusion group, patients received RBC transfusion for haemoglobin levels below 8g/dl (2007-2014). In the restrictive transfusion group, patients received RBC transfusion for haemoglobin levels below 7g/dl (2016-2018). Liberal transfusion triggers were never endorsed. A total of 268 (76·1%) and 84 (23·9%) AML patients fell into the less restrictive and restrictive transfusion groups, respectively. The less restrictive transfusion group had 1g/dl higher mean haemoglobin levels, received their first RBC transfusions earlier and needed 1·5 more units of RBC during the hospital stay of induction chemotherapy. Febrile episodes, C-reactive protein levels, admission to the intensive care unit, length of hospital stay as well as response and survival rates did not differ between the two cohorts. From our retrospective analysis, we conclude that a more restrictive transfusion trigger does not affect important outcomes of AML patients. The opportunity to test possible effects of the more severe anaemia in the restrictive transfusion group on quality of life was missed.

Long-term outcome of brain structure in female preterm infants: possible associations of liberal versus restrictive red blood cell transfusions

Background Preterm infants who receive differential red blood cell (RBC) transfusions at birth may show brain structure differences across development, including abnormalities in white matter (WM) structure and organization. This study investigated long-term outcomes of brain structure in female infants born preterm, at an average age of 13 years old, who received red blood cell (RBC) transfusions in the neonatal period according to a liberal or restrictive approach. Results from this study will increase understanding of the effects of transfusion on the developing brain. Study design and methods This follow-up study included female preterm infants who participated in a clinical trial and had been randomized at birth to either a liberal or restrictive hematocrit threshold. Brain structures were measured in childhood using structural magnetic resonance imaging (MRI) scans. Due to the low number of females in the restrictive transfusion group at follow-up, additional females were recruited for inclusion. Main outcome measures included cerebral and subcortical brain region volumes. Results Total intracranial volume was significantly decreased in females who were randomized to higher average hematocrit levels at birth. Infants in the liberal transfusion group had proportionately smaller volumes in all measures of regional cerebral WM and subcortical brain volumes, reaching significance for temporal lobe WM and caudate volumes. Conclusion Female premature infants who received a liberal transfusion threshold at birth had decreased WM volumes, which suggests the potential long-term neurodevelopmental risks associated with liberal transfusion practices.

Liberal versus restrictive red blood cell transfusion strategy in sepsis or septic shock: a systematic review and meta-analysis of randomized trials

BackgroundWe assessed the effect of liberal versus restrictive red blood cell transfusion strategy on survival outcome in sepsis or septic shock by systematically reviewing the literature and synthesizing evidence from randomized controlled trials (RCTs).MethodsWe searched the MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science databases. We included RCTs that compared mortality between a liberal transfusion strategy with a hemoglobin threshold of 9 or 10 g/dL and a restrictive transfusion strategy with a hemoglobin threshold of 7 g/dL in adults with sepsis or septic shock. Two investigators independently screened citations and conducted data extraction. The primary outcome was 28- or 30-day mortality. Secondary outcomes were 60- and 90-day mortality, use of life support at 28 days of admission, and number of patients transfused during their intensive care unit stay. DerSimonian-Laird random-effects models were used to report pooled odds ratios (ORs).ResultsA total of 1516 patients from three RCTs were included; 749 were randomly assigned to the liberal transfusion group and 767 to the restrictive strategy group. Within 28–30 days, 273 patients (36.4%) died in the liberal transfusion group, while 278 (36.2%) died in the restrictive transfusion group (pooled OR, 0.99; 95% confidence interval [CI], 0.67–1.46). For the primary outcome, heterogeneity was observed among the studies (I2 = 61.0%, χ2 = 5.13, p = 0.08). For secondary outcomes, only two RCTs were included. There were no significant differences in secondary outcomes between the two groups.ConclusionsWe could not show any difference in 28- or 30-day mortality between the liberal and restrictive transfusion strategies in sepsis or septic shock patients by meta-analysis of RCTs. Our results should be interpreted with caution due to the existence of heterogeneity. As sepsis complicates a potentially wide range of underlying diseases, further trials in carefully selected populations are anticipated.Trial registrationThis present study was registered in the PROSPERO database (CRD42018108578).

Platelet Transfusion for PDA Closure in Preterm Infants: A Randomized Controlled Trial.

Thrombocytopenia is associated with late closure of patent ductus arteriosus (PDA). There are few studies evaluating platelet transfusions to treat PDA. We compared liberal platelet-transfusion criteria (to maintain a platelet count >100 000 per µL) versus standard criteria achieve earlier PDA closure among thrombocytopenic preterm neonates (<35 weeks' gestation) with hemodynamically significant PDA (hs-PDA) presenting within the first 2 weeks of life. Thrombocytopenic (<100 000 per µL) preterm neonates with hs-PDA were enrolled and randomly allocated to the liberal and standard transfusion groups: 22 in each arm. They underwent echocardiography daily until closure of PDA, completion of 120 hours follow-up, or death. All subjects received standard cotreatment with nonsteroidal antiinflammatory drugs. Primary outcome of time to PDA closure was compared by survival analysis. Multivariate Cox proportional hazard regression was performed with randomization group, baseline platelet count, gestational age, and age at enrollment as predictor variables. Median time to PDA closure was 72 (95% confidence interval [CI] 55.9-88.1) versus 72 (95% CI 45.5-98.4) hours in the liberal versus restrictive transfusion groups, respectively (unadjusted hazard ratio 0.88 [95% CI 0.4-1.9]; P = .697). Despite adjusting for potential confounders, there was no significant difference in time to PDA closure. In the liberal transfusion group, 41% of infants had any grade of intraventricular hemorrhage compared with 4.5% in the restrictive group (P = .009). Attempting to maintain a platelet count >100 000 per µL by liberally transfusing platelets in preterm thrombocytopenic neonates with hs-PDA does not hasten PDA closure.

Red cell transfusion thresholds in haematopoietic stem cell transplantation

Red cell transfusions are part of the routine supportive care following haematopoietic stem cell transplantation. There is increasing evidence from randomized controlled trials demonstrating that restrictive transfusion thresholds are equivalent to liberal thresholds in other patient populations. However, given the lack of patient‐centred outcomes and the longer transfusion support required for patients with haematologic malignancies, the results of these trials may not be generalizable to haematology–oncology patients. In the recently completed multicentre TRIST trial, we randomized 300 patients requiring an autologous or allogeneic haematopoietic stem cell transplantation to either a restrictive (haemoglobin threshold &lt;70 g/l) or liberal (haemoglobin threshold &lt;90 g/l) red cell transfusion strategy. Our primary outcome was health‐related quality of life measured by FACT‐BMT through day 100 post‐transplant. The median number of red cell units transfused was lower in the restrictive strategy group (2 vs. 4). The FACT‐BMT total score was higher at all time points for patients in the restrictive transfusion group including at baseline (109 vs. 103) and at 100 days (116·3 vs. 109·2). After adjustment for baseline, the FACT‐BMT score at day 100 in the restrictive group was statistically non‐inferior to the liberal group (P &lt; 0·0001). There were no significant differences between the two groups for any other clinical outcomes. Based on the results of the TRIST trial, a restrictive haemoglobin threshold of 70 g/l should become standard practice in haematopoietic stem cell transplant patients, and, given the lack of other clinical studies, all other haematology–oncology inpatients.

Retrospective Evaluation of a Restrictive Transfusion Strategy in Older Adults with Hip Fracture.

To compare the association between a restrictive transfusion strategy and cardiovascular complications during hospitalization for hip fracture with the association between a liberal transfusion strategy and cardiovascular complications, accounting for all transfusions from the emergency department to postacute rehabilitation settings. Retrospective study. Perioperative geriatric care unit. All individuals aged 70 and older admitted to the emergency department for hip fracture and hospitalized in our perioperative geriatric care unit (N=667; n=193 in the liberal transfusion group, n=474 in the restrictive transfusion group) from July 2009 to April 2016. A restrictive transfusion strategy (hemoglobin level threshold ≥8 g/dL or symptoms) used from January 2012 to April 2016 was compared with the liberal transfusion strategy (hemoglobin level threshold ≥10 g/dL) used from July 2009 to December 2011. Primary endpoint was in-hospital acute cardiovascular complications (heart failure, myocardial infarction, atrial fibrillation or stroke). The change to a restrictive transfusion strategy was associated with fewer acute cardiovascular complications (odds ratio=0.45, 95% confidence interval (CI)=0.31-0.67, p<.001), without any noticeable difference in in-hospital or 6-month mortality. The change also led to a reduction in packed red blood cell units used per participant (median 1, interquartile range (IQR) 0-2 in restrictive vs median 2, IQR 0-3 in liberal transfusion strategy, P<.001). In rehabilitation settings, the frequency of transfusion was greater with the restrictive transfusion strategy than the liberal transfusion strategy (18% vs 9%, P<.001). A restrictive transfusion strategy in older adults with hip fracture was found to be safe and was associated with fewer cardiovascular complications but more transfusions in rehabilitation settings. Prospective studies are needed to confirm these findings.

Transfusion Requirements in Cardiac Surgery III (TRICS III): Study Design of a Randomized Controlled Trial

To determine if a restrictive transfusion threshold is noninferior to a higher threshold as measured by a composite outcome of mortality and serious morbidity. Transfusion Requirements in Cardiac Surgery (TRICS) III was a multicenter, international, open-label randomized controlled trial of two commonly used transfusion strategies in patients having cardiac surgery using a noninferiority trial design (ClinicalTrials.gov number, NCT02042898). Eligible patients were randomized prior to surgery in a 1:1 ratio. Potential participants were 18 years or older undergoing planned cardiac surgery using cardiopulmonary bypass (CPB) with a preoperative European System for Cardiac Operative Risk Evaluation (EuroSCORE I) of 6 or more. Five thousand patients; those allocated to a restrictive transfusion group received a red blood cell (RBC) transfusion if the hemoglobin concentration (Hb) was less than 7.5 g/dL intraoperatively and/or postoperatively. Patients allocated to a liberal transfusion strategy received RBC transfusion if the Hb was less than 9.5 g/dL intraoperatively or postoperatively in the intensive care unit or less than 8.5 g/dL on the ward. The primary outcome was a composite of all-cause mortality, myocardial infarction, stroke, or new onset renal dysfunction requiring dialysis at hospital discharge or day 28, whichever comes first. The primary outcome was analyzed as a per-protocol analysis. The trial monitored adherence closely as adherence to the transfusion triggers is important in ensuring that measured outcomes reflect the transfusion strategy. By randomizing prior to surgery, the TRICS III trial captured the most acute reduction in hemoglobin during cardiopulmonary bypass.

Restrictive versus liberal blood transfusion for gastrointestinal bleeding: a systematic review and meta-analysis of randomised controlled trials

Acute upper gastrointestinal bleeding is a leading indication for red blood cell (RBC) transfusion worldwide, although optimal thresholds for transfusion are debated. We searched MEDLINE, Embase, CENTRAL, CINAHL, and the Transfusion Evidence Library from inception to Oct 20, 2016, for randomised controlled trials comparing restrictive and liberal RBC transfusion strategies for acute upper gastrointestinal bleeding. Main outcomes were mortality, rebleeding, ischaemic events, and mean RBC transfusion. We computed pooled estimates for each outcome by random effects meta-analysis, and individual participant data for a cluster randomised trial were re-analysed to facilitate meta-analysis. We compared treatment effects between patient subgroups, including patients with liver cirrhosis, patients with non-variceal upper gastrointestinal bleeding, and patients with ischaemic heart disease at baseline. We included four published and one unpublished randomised controlled trial, totalling 1965 participants. The number of RBC units transfused was lower in the restrictive transfusion group than in the liberal transfusion group (mean difference -1·73 units, 95% CI -2·36 to -1·11, p<0·0001). Restrictive transfusion was associated with lower risk of all-cause mortality (relative risk [RR] 0·65, 95% CI 0·44-0·97, p=0·03) and rebleeding overall (0·58, 0·40-0·84, p=0·004). We detected no difference in risk of ischaemic events. There were no statistically significant differences in the subgroups. These results support more widespread implementation of restrictive transfusion policies for adults with acute upper gastrointestinal bleeding. None.

Transfusion of Red Cells in Hematopoietic Stem Cell Transplantation (TRIST Study): A Randomized Controlled Trial Evaluating 2 Red Cell Transfusion Thresholds

▪BackgroundEvidence regarding red blood cell (RBC) transfusion practices in Hematopoietic Stem Cell Transplantation (HSCT) is lacking. As a result, the impact of RBC transfusions on outcomes following HSCT is not well understood. We designed a non-inferiority Randomized Controlled Trial evaluating a restrictive and liberal RBC transfusion strategy with a primary endpoint of Health Related Quality of Life (HRQOL) as measured by the FACT-BMT scale at Day 100.MethodsPatients with a hematologic malignancy requiring HSCT were randomized to either a restrictive (Hemoglobin (Hgb) threshold <70g/L) or liberal (Hgb threshold <90g/L) RBC transfusion strategies between Day-0 and Day-100). Permutated randomization blocks of 2 and 4 were used. Patients were stratified by centre and by type of HSCT. The non-inferiority margin selected for the study corresponds to a 12% absolute difference between groups in FACT-BMT score relative to baseline. Patients received a RBC transfusion if the Hgb was below the assigned threshold with the assessment of hemoglobin according to institutional practice (most often on a daily basis) with 2 units of RBC prescribed at the assigned threshold. The following endpoints were collected: 1) HRQOL by FACT-BMT, FACT-Anemia and EQ-5D at Baseline, Day 7, 14, 28, 60 and 100, 2) Transplant related mortality, Length of Hospital Stay, ICU admissions, Incidence and grade of acute graft versus host disease, Incidence of Serious infections, Transfusion requirements, Bleeding as per WHO Bleeding Scale, Incidence of adverse transfusion reactions, Bearman Toxicity Score and Sinusoidal Obstruction Syndrome. The primary endpoint was compared using a generalized linear model while accounting for any baseline differences in scores.ResultsWe enrolled 300 patients (150 allogeneic and 150 autologous) undergoing HSCT between 28 Mar 2011 and 3 Feb 2016 at 4 Canadian adult HSCT centres. The difference in the overall mean pre-transfusion hemoglobin per patient over the study period between the groups was 13.7(±9.8) g/L. Statistical non-inferiority was detected between the liberal and the restrictive strategy as measured by the FACT-BMT at 100 days post-HSCT (Estimated difference in ratios between groups, -1.64%; 95% confidence interval, -0.07 to 0.04; P=0.0001 for non-inferiority) or any other time points (Days 7, 14, 28 and 60). In fact, the FACT BMT scores at all time points were higher for patients in the restrictive transfusion group. The median (IQR) number of RBC units transfused was lower in the restrictive-strategy group than in the liberal-strategy group [2(2-6) vs. 4(2-6), p=0.10], but this did not reach statistical significance. There were no statistical differences in any of the outcomes between the 2 groups.ConclusionsThe results of our study support the use of a restrictive RBC transfusion strategy as compared with a liberal strategy in patients undergoing HSCT as the HRQOL are similar and there are no appreciable differences in HSCT associated clinical outcomes. [Display omitted] DisclosuresXenocostas:Janssen Inc.: Research Funding.

Transfusion thresholds and other strategies for guiding allogeneic red blood cell transfusion.

There is considerable uncertainty regarding the optimal haemoglobin threshold for the use of red blood cell (RBC) transfusions in anaemic patients. Blood is a scarce resource, and in some countries, transfusions are less safe than others because of a lack of testing for viral pathogens. Therefore, reducing the number and volume of transfusions would benefit patients. The aim of this review was to compare 30-day mortality and other clinical outcomes in participants randomized to restrictive versus liberal red blood cell (RBC) transfusion thresholds (triggers) for all conditions. The restrictive transfusion threshold uses a lower haemoglobin level to trigger transfusion (most commonly 7 g/dL or 8 g/dL), and the liberal transfusion threshold uses a higher haemoglobin level to trigger transfusion (most commonly 9 g/dL to 10 g/dL). We identified trials by searching CENTRAL (2016, Issue 4), MEDLINE (1946 to May 2016), Embase (1974 to May 2016), the Transfusion Evidence Library (1950 to May 2016), the Web of Science Conference Proceedings Citation Index (1990 to May 2016), and ongoing trial registries (27 May 2016). We also checked reference lists of other published reviews and relevant papers to identify any additional trials. We included randomized trials where intervention groups were assigned on the basis of a clear transfusion 'trigger', described as a haemoglobin (Hb) or haematocrit (Hct) level below which a red blood cell (RBC) transfusion was to be administered. We pooled risk ratios of clinical outcomes across trials using a random-effects model. Two people extracted the data and assessed the risk of bias. We conducted predefined analyses by clinical subgroups. We defined participants randomly allocated to the lower transfusion threshold as 'restrictive transfusion' and to the higher transfusion threshold as 'liberal transfusion'. A total of 31 trials, involving 12,587 participants, across a range of clinical specialities (e.g. surgery, critical care) met the eligibility criteria. The trial interventions were split fairly equally with regard to the haemoglobin concentration used to define the restrictive transfusion group. About half of them used a 7 g/dL threshold, and the other half used a restrictive transfusion threshold of 8 g/dL to 9 g/dL. The trials were generally at low risk of bias .Some items of methodological quality were unclear, including definitions and blinding for secondary outcomes.Restrictive transfusion strategies reduced the risk of receiving a RBC transfusion by 43% across a broad range of clinical specialties (risk ratio (RR) 0.57, 95% confidence interval (CI) 0.49 to 0.65; 12,587 participants, 31 trials; high-quality evidence), with a large amount of heterogeneity between trials (I² = 97%). Overall, restrictive transfusion strategies did not increase or decrease the risk of 30-day mortality compared with liberal transfusion strategies (RR 0.97, 95% CI 0.81 to 1.16, I² = 37%; N = 10,537; 23 trials; moderate-quality evidence) or any of the other outcomes assessed (i.e. cardiac events (low-quality evidence), myocardial infarction, stroke, thromboembolism (high-quality evidence)). Liberal transfusion did not affect the risk of infection (pneumonia, wound, or bacteraemia). Transfusing at a restrictive haemoglobin concentration of between 7 g/dL to 8 g/dL decreased the proportion of participants exposed to RBC transfusion by 43% across a broad range of clinical specialities. There was no evidence that a restrictive transfusion strategy impacts 30-day mortality or morbidity (i.e. mortality at other points, cardiac events, myocardial infarction, stroke, pneumonia, thromboembolism, infection) compared with a liberal transfusion strategy. There were insufficient data to inform the safety of transfusion policies in certain clinical subgroups, including acute coronary syndrome, myocardial infarction, neurological injury/traumatic brain injury, acute neurological disorders, stroke, thrombocytopenia, cancer, haematological malignancies, and bone marrow failure. The findings provide good evidence that transfusions with allogeneic RBCs can be avoided in most patients with haemoglobin thresholds above 7 g/dL to 8 g/dL.

LO077: A restrictive transfusion strategy decreases mortality, re-bleeding and adverse events in hemodynamically stable patients with acute upper gastrointestinal bleeding: findings from a systematic review and meta-analysis of randomized controlled trials

Introduction: Acute upper gastrointestinal bleeding is a potentially life-threatening medical emergency that frequently requires red blood cell (RBC) transfusions. However, the optimal hemoglobin thresholds for transfusion is controversial. The objective of this study was to establish the most efficacious transfusion threshold. Methods: A systematic review of the published literature was completed. MEDLINE, Health technology assessment database, Cochrane central register, Cochrane database of systematic reviews, and EMBASE were searched from inception to May 2015 using search terms including “blood transfusions”, “hemoglobin”, and “red blood cell”. Studies were included if they: reported original data, were peer-reviewed, studied adult populations, were randomized controlled clinical trials and primarily focused on clinical efficacy or effectiveness of liberal and restrictive pre-transfusion hemoglobin level thresholds. Quality was assessed using the Cochrane Risk of Bias tool. Data were extracted and meta-analysis was conducted using a random effects model to determine the risk ratio for: all-cause mortality, further bleeding and any adverse events. All steps were completed independently by two reviewers. Results: The literature search identified 4037 unique abstracts. Of these, 156 abstracts proceeded to full text review. 154 articles were excluded during full-text review resulting in 2 articles for final analysis. The total number of participants included was 701. The hemoglobin threshold to transfuse RBC varied between 70-80g/L versus 90-100g/L in restrictive and liberal policies, respectively. Both studies were at low risk of bias. Meta-analysis resulted in a pooled decreased risk of all-cause mortality (RR 0.65, 95% CI 0.44-0.96), re-bleeding (RR 0.63, 95% CI 0.46-0.85) and adverse events (RR 0.83, 95% CI 0.73-0.95) in the restrictive blood transfusion group versus the liberal blood transfusion group. Conclusion: While the evidence is limited, the risk of death is lower and there is no significant harm for a restrictive strategy. In this context, there is a decreased risk of transfusion associated adverse events among those receiving a restrictive strategy and should be considered for its impact on patient safety and health system resources.