Health care-associated infection after red blood cell transfusion: a systematic review and meta-analysis.
ABSTRACT: The association between red blood cell (RBC) transfusion strategies and health care-associated infection is not fully understood.To evaluate whether RBC transfusion thresholds are associated with the risk of infection and whether risk is independent of leukocyte reduction.MEDLINE, EMBASE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, Cochrane Database of Sytematic Reviews, ClinicalTrials.gov, International Clinical Trials Registry, and the International Standard Randomized Controlled Trial Number register were searched through January 22, 2014.Randomized clinical trials with restrictive vs liberal RBC transfusion strategies.Twenty-one randomized trials with 8735 patients met eligibility criteria, of which 18 trials (n?=?7593 patients) contained sufficient information for meta-analyses. DerSimonian and Laird random-effects models were used to report pooled risk ratios. Absolute risks of infection were calculated using the profile likelihood random-effects method.Incidence of health care-associated infection such as pneumonia, mediastinitis, wound infection, and sepsis.The pooled risk of all serious infections was 11.8% (95% CI, 7.0%-16.7%) in the restrictive group and 16.9% (95% CI, 8.9%-25.4%) in the liberal group. The risk ratio (RR) for the association between transfusion strategies and serious infection was 0.82 (95% CI, 0.72-0.95) with little heterogeneity (I2?=?0%; ?2 <.0001). The number needed to treat (NNT) with restrictive strategies to prevent serious infection was 38 (95% CI, 24-122). The risk of infection remained reduced with a restrictive strategy, even with leukocyte reduction (RR, 0.80 [95% CI, 0.67-0.95]). For trials with a restrictive hemoglobin threshold of <7.0 g/dL, the RR was 0.82 (95% CI, 0.70-0.97) with NNT of 20 (95% CI, 12-133). With stratification by patient type, the RR was 0.70 (95% CI, 0.54-0.91) in patients undergoing orthopedic surgery and 0.51 (95% CI, 0.28-0.95) in patients presenting with sepsis. There were no significant differences in the incidence of infection by RBC threshold for patients with cardiac disease, the critically ill, those with acute upper gastrointestinal bleeding, or for infants with low birth weight.Among hospitalized patients, a restrictive RBC transfusion strategy was associated with a reduced risk of health care-associated infection compared with a liberal transfusion strategy. Implementing restrictive strategies may have the potential to lower the incidence of health care-associated infection.
Project description:This study sought to evaluate whether restrictive blood transfusion strategies are associated with a risk of infection in orthopedic patients by conducting a meta-analysis of randomized controlled trials (RCTs). RCTs with restrictive versus liberal red blood cell (RBC) transfusion strategies were identified by searching Medline, Embase, the Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Reviews from their inception to December 2014. Eight RCTs with infections as outcomes were included in the final analysis. According to the Jadad scale, all studies were considered to be of high quality. The pooled risk ratio [RR] for the association between transfusion strategy and infection was 0.65 (95% CI, 0.47-0.91; p = 0.012), and the number of patients needed to treat to avoid an infection using a restrictive transfusion strategy was 62. No heterogeneity was observed. The sensitivity analysis indicated unstable results, and no significant publication bias was observed. This meta-analysis of RCTs demonstrates that restrictive transfusion strategies in orthopedic patients result in a significant reduction in infections compared with more liberal strategies.
Project description:OBJECTIVE:To address the significant uncertainty as to whether transfusion thresholds for critical care versus surgical patients should differ. DESIGN:Meta-analysis of randomized controlled trials. SETTING:Medline, EMBASE, and Cochrane Library searches were performed up to 15 June 2016. PATIENTS:Trials had to enroll adult surgical or critically ill patients for inclusion. INTERVENTIONS:Studies had to compare a liberal versus restrictive threshold for the transfusion of allogeneic packed RBCs. MEASUREMENTS AND MAIN RESULTS:The primary outcome was 30-day all-cause mortality, sub-grouped by surgical and critical care patients. Secondary outcomes included myocardial infarction, stroke, renal failure, allogeneic blood exposure, and length of stay. Odds ratios and weighted mean differences were calculated using random effects meta-analysis. To assess whether subgroups were significantly different, tests for subgroup interaction were used. Subgroup analysis by trials enrolling critically ill versus surgical patients was performed. Twenty-seven randomized controlled trials (10,797 patients) were included. In critical care patients, restrictive transfusion resulted in significantly reduced 30-day mortality compared with liberal transfusion (odds ratio, 0.82; 95% CI, 0.70-0.97). In surgical patients, a restrictive transfusion strategy led to the opposite direction of effect for mortality (odds ratio, 1.31; 95% CI, 0.94-1.82). The subgroup interaction test was significant (p = 0.04), suggesting that the effect of restrictive transfusion on mortality is statistically different for critical care (decreased risk) versus surgical patients (potentially increased risk or no difference). Regarding secondary outcomes, for critically ill patients, a restrictive strategy resulted in reduced risk of stroke/transient ischemic attack, packed RBC exposure, transfusion reactions, and hospital length of stay. In surgical patients, restrictive transfusion resulted in reduced packed RBC exposure. CONCLUSIONS:The safety of restrictive transfusion strategies likely differs for critically ill patients versus perioperative patients. Further trials investigating transfusion strategies in the perioperative setting are necessary.
Project description:Restrictive red blood cell transfusion strategies remain controversial in patients undergoing cardiac surgery. We performed a meta-analysis to assess the prognostic benefits of restrictive red blood cell transfusion strategies in patients undergoing cardiac surgery.We identified randomized clinical trials through the 9th of December 2017 that investigated a restrictive red blood cell transfusion strategy versus a liberal transfusion strategy in patients undergoing cardiac surgery. Individual patient data from each study were collected. Meta-analyses were performed for the primary and secondary outcomes. The risk of bias was assessed using the Cochrane Risk of Bias Tool. A trial sequential analysis (TSA)-adjusted random-effects model was used to pool the results from the included studies for the primary outcomes.Seven trials involving a total of 8886 patients were included. The TSA evaluations suggested that this meta-analysis could draw firm negative results, and the data were sufficient. There was no evidence that the risk of 30-day mortality differed between the patients assigned to a restrictive blood cell transfusion strategy and a liberal transfusion strategy (odds ratio (OR) 0.98; 95% confidence interval (CI) 0.77 to 1.24; p?=?0.87). Furthermore, the study suggested that the restrictive transfusion strategy was not associated with significant increases in pulmonary morbidity (OR 1.09; 95% CI 0.88 to 1.34; p?=?0.44), postoperative infection (OR 1.11; 95% CI 0.95 to 1.3; p?=?0.58), acute kidney injury (OR 1.03; 95% CI 0.92 to 1.14; p?=?0.71), acute myocardial infarction (OR 1.01; 95% CI 0.80 to 1.27; p?=?0.78), or cerebrovascular accidents (OR 0.97; 95% CI 0.72 to 1.30; p?=?0.66).Our meta-analysis demonstrates that the restrictive red blood cell transfusion strategy was not inferior to the liberal strategy with respect to 30-day mortality, pulmonary morbidity, postoperative infection, cerebrovascular accidents, acute kidney injury, or acute myocardial infarction, and fewer red blood cells were transfused.
Project description:BACKGROUND:Bone marrow failure disorders include a heterogenous group of disorders, of which myelodysplastic syndrome (MDS), forms the largest subgroup. MDS is predominantly a disease of the elderly, with many elderly people managed conservatively with regular allogeneic red blood cell (RBC) transfusions to treat their anaemia. However, RBC transfusions are not without risk. Despite regular transfusions playing a central role in treating such patients, the optimal RBC transfusion strategy (restrictive versus liberal) is currently unclear. OBJECTIVES:To assess the efficacy and safety of a restrictive versus liberal red blood cell transfusion strategy for patients with myelodysplasia, acquired aplastic anaemia, and other inherited bone marrow failure disorders. SEARCH METHODS:We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 4), Ovid MEDLINE (from 1946), Ovid EMBASE (from 1974), EBSCO CINAHL (from 1937), the Transfusion Evidence Library (from 1980) and ongoing trial databases to 26th May 2015. SELECTION CRITERIA:RCTs including patients with long-term bone marrow failure disorders that require allogeneic blood transfusion, who are not being actively treated with a haematopoietic stem cell transplant, or intensive chemotherapy. DATA COLLECTION AND ANALYSIS:We used standard Cochrane review methodology. One author initially screened all references, and excluded any that were clearly irrelevant or duplicates. Two authors then independently screened all abstracts of articles, identified by the review search strategy, for relevancy. Two authors independently assessed the full text of all potentially relevant articles for eligibility, completed the data extraction and assessed the studies for risk of bias using The Cochrane Collaboration's 'Risk of bias' tool. MAIN RESULTS:We included one trial (13 participants) and identified three ongoing trials that assess RBC transfusion strategies in people with MDS.The quality of the evidence was very low across different outcomes according to GRADE methodology.The one included study randomised participants to a restrictive [haemoglobin (Hb) transfusion trigger < 72 g/L, 8 participants] or liberal [Hb trigger < 96 g/L, 5 participants] transfusion policy. There was insufficient evidence to determine a difference in all-cause mortality (1 RCT; 13 participants; RR 0.13, 95% CI 0.01 to 2.32; very low quality evidence). There was insufficient evidence to determine a difference in the number of red blood cell transfusions (1 RCT; 13 participants; 1.8 units per patient per month in the liberal group, compared to 0.8 in the restrictive arm, no standard deviation was reported; very low quality evidence). There were no anaemia-related complications reported (cardiac failure) and no reported effect on activity levels (no statistics provided). The study did not report: mortality due to bleeding/infection/transfusion reactions or iron overload, quality of life, frequency and length of hospital admissions, serious infections (requiring admission to hospital), or serious bleeding (e.g. WHO/CTCAE grade 3 (or equivalent) or above). AUTHORS' CONCLUSIONS:This review indicates that there is currently a lack of evidence for the recommendation of a particular transfusion strategy for bone marrow failure patients undergoing supportive treatment only. The one RCT included in this review was only published as an abstract and contained only 13 participants. Further randomised trials with robust methodology are required to develop the optimal transfusion strategy for such patients, particularly as the incidence of the main group of bone marrow failure disorders, MDS, rises with an ageing population.
Project description:Hip fracture (HF) in frail elderly patients is associated with poor physical recovery and death. There is often postoperative blood loss and the hemoglobin (Hb) threshold for red blood cell (RBC) transfusions in these patients is unknown. We investigated whether RBC transfusion strategies were associated with the degree of physical recovery or with reduced mortality after HF surgery.We enrolled 284 consecutive post-surgical HF patients (aged ? 65 years) with Hb levels < 11.3 g/dL (7 mmol/L) who had been admitted from nursing homes or sheltered housing. Allocation was stratified by residence. The patients were randomly assigned to either restrictive (Hb < 9.7 g/dL; < 6 mmol/L) or liberal (Hb < 11.3 g/dL; < 7 mmol/L) RBC transfusions given within the first 30 days postoperatively. Follow-up was at 90 days.No statistically significant differences were found in repeated measures of daily living activities or in 90-day mortality rate between the restrictive group (where 27% died) and the liberal group (where 21% died). Per-protocol 30-day mortality was higher with the restrictive strategy (hazard ratio (HR) = 2.4, 95% CI: 1.1-5.2; p = 0.03). The 90-day mortality rate was higher for nursing home residents in the restrictive transfusion group (36%) than for those in the liberal group (20%) (HR = 2.0, 95% CI: 1.1-3.6; p = 0.01).According to our Hb thresholds, recovery from physical disabilities in frail elderly hip fracture patients was similar after a restrictive RBC transfusion strategy and after a liberal strategy. Implementation of a liberal RBC transfusion strategy in nursing home residents has the potential to increase survival.
Project description:Most non-oncologic clinical practice guidelines recommend restrictive allogeneic blood transfusion practices; however, there is a lack of consensus regarding the best transfusion practice in oncology. We conducted a systematic review of the literature to compare the efficacy and safety of restrictive versus liberal transfusion strategies in patients with cancer.A literature search using MEDLINE, PUBMED and EMBASE identified all controlled studies comparing the use of restrictive with liberal transfusion in adult oncology participants up to August 10, 2015. Two review authors independently assessed studies for inclusion, extracted data and appraised the quality of the included studies. The primary outcomes of interest were blood utilization and all-cause mortality.Out of 4241 citations, six studies (3 randomized and 3 non-randomized) involving a total of 983 patients were included in the final review. The clinical context of the studies varied with 3 chemotherapy and 3 surgical studies. The overall risk of bias in all studies was moderate to high. Restrictive transfusion strategies were associated with a 36% reduced risk of receiving a perioperative transfusion (risk ratio (RR) 0.64, 95% confidence interval (CI) 0.49-0.83). There was no difference in mortality between the strategies (RR 1.00, 95% CI 0.32-3.18). There were no differences in adverse events reported between the restrictive and liberal transfusion strategies.Restrictive strategy appears to decrease blood utilization without increasing morbidity or mortality in oncology. This review is limited by a paucity of high quality studies on this topic. Better designed studies are warranted.
Project description:Cell salvage is commonly used as part of a blood conservation strategy. However concerns among clinicians exist about the efficacy of transfusion of washed cell salvage.We performed a meta-analysis of randomized controlled trials in which patients, scheduled for all types of surgery, were randomized to washed cell salvage or to a control group with no cell salvage. Data were independently extracted, risk ratio (RR), and weighted mean differences (WMD) with 95% confidence intervals (CIs) were calculated. Data were pooled using a random effects model. The primary endpoint was the number of patients exposed to allogeneic red blood cell (RBC) transfusion.Out of 1140 search results, a total of 47 trials were included. Overall, the use of washed cell salvage reduced the rate of exposure to allogeneic RBC transfusion by a relative 39% (RR?=?0.61; 95% CI 0.57 to 0.65; P?<?0.001), resulting in an average saving of 0.20 units of allogeneic RBC per patient (weighted mean differences [WMD]?=?-0.20; 95% CI -0.22 to -0.18; P?<?0.001), reduced risk of infection by 28% (RR?=?0.72; 95% CI 0.54 to 0.97; P?=?0.03), reduced length of hospital stay by 2.31 days (WMD?=?-2.31; 95% CI -2.50 to -2.11; P?<?0.001), but did not significantly affect risk of mortality (RR?=?0.92; 95% CI 0.63 to 1.34; P?=?0.66). No statistical difference could be observed in the number of patients exposed to re-operation, plasma, platelets, or rate of myocardial infarction and stroke.Washed cell salvage is efficacious in reducing the need for allogeneic RBC transfusion and risk of infection in surgery.
Project description:AIM:To evaluate the risks of restrictive red blood cell transfusion strategies (haemoglobin 7-8 g?dL-1 ) in patients with and without known cardiovascular disease (CVD). BACKGROUND:Recent guidelines recommend restrictive strategies for CVD patients hospitalised for non-CVD indications, patients without known CVD and patients hospitalised for CVD corrective procedures. METHODS/MATERIALS:Database searches were conducted through December 2017 for randomised clinical trials that enrolled patients with and without known CVD, hospitalised either for CVD-corrective procedures or non-cardiac indications, comparing effects of liberal with restrictive strategies on major adverse coronary events (MACE) and death. RESULTS:In CVD patients not undergoing cardiac interventions, a liberal strategy decreased (P?=?0·01) the relative risk (95% CI) (RR) of MACE [0·50 (0·29-0·86)] (I2 =?0%). Among patients without known CVD, the incidence of MACE was lower (1·7 vs 3·9%), and the effect of a liberal strategy on MACE [0·79, (0·39-1·58)] was smaller and non-significant but not different from CVD patients (P?=?0·30). Combining all CVD and non-CVD patients, a liberal strategy decreased MACE [0·59, (0·39-0·91); P?=?0·02]. Conversely, among studies reporting mortality, a liberal strategy decreased mortality in CVD patients (11·7% vs·13·3%) but increased mortality (19·2% vs 18·0%) in patients without known CVD [interaction P?=?0·05; ratio of RR 0·73, (0·53-1·00)]. A liberal strategy also did not benefit patients undergoing cardiac surgery; data were insufficient for percutaneous cardiac procedures. CONCLUSIONS:In patients hospitalised for non-cardiac indications, liberal transfusion strategies are associated with a decreased risk of MACE in both those with and without known CVD. However, this only provides a survival benefit to CVD patients not admitted for CVD-corrective procedures.
Project description:<h4>Objective</h4>To compare the benefit and harm of restrictive versus liberal transfusion strategies to guide red blood cell transfusions.<h4>Design</h4>Systematic review with meta-analyses and trial sequential analyses of randomised clinical trials.<h4>Data sources</h4>Cochrane central register of controlled trials, SilverPlatter Medline (1950 to date), SilverPlatter Embase (1980 to date), and Science Citation Index Expanded (1900 to present). Reference lists of identified trials and other systematic reviews were assessed, and authors and experts in transfusion were contacted to identify additional trials.<h4>Trial selection</h4>Published and unpublished randomised clinical trials that evaluated a restrictive compared with a liberal transfusion strategy in adults or children, irrespective of language, blinding procedure, publication status, or sample size.<h4>Data extraction</h4>Two authors independently screened titles and abstracts of trials identified, and relevant trials were evaluated in full text for eligibility. Two reviewers then independently extracted data on methods, interventions, outcomes, and risk of bias from included trials. random effects models were used to estimate risk ratios and mean differences with 95% confidence intervals.<h4>Results</h4>31 trials totalling 9813 randomised patients were included. The proportion of patients receiving red blood cells (relative risk 0.54, 95% confidence interval 0.47 to 0.63, 8923 patients, 24 trials) and the number of red blood cell units transfused (mean difference -1.43, 95% confidence interval -2.01 to -0.86) were lower with the restrictive compared with liberal transfusion strategies. Restrictive compared with liberal transfusion strategies were not associated with risk of death (0.86, 0.74 to 1.01, 5707 patients, nine lower risk of bias trials), overall morbidity (0.98, 0.85 to 1.12, 4517 patients, six lower risk of bias trials), or fatal or non-fatal myocardial infarction (1.28, 0.66 to 2.49, 4730 patients, seven lower risk of bias trials). Results were not affected by the inclusion of trials with unclear or high risk of bias. Using trial sequential analyses on mortality and myocardial infarction, the required information size was not reached, but a 15% relative risk reduction or increase in overall morbidity with restrictive transfusion strategies could be excluded.<h4>Conclusions</h4>Compared with liberal strategies, restrictive transfusion strategies were associated with a reduction in the number of red blood cell units transfused and number of patients being transfused, but mortality, overall morbidity, and myocardial infarction seemed to be unaltered. Restrictive transfusion strategies are safe in most clinical settings. Liberal transfusion strategies have not been shown to convey any benefit to patients.<h4>Trial registration</h4>PROSPERO CRD42013004272.
Project description:<h4>Objective</h4>To compare patient outcomes of restrictive versus liberal blood transfusion strategies in patients with cardiovascular disease not undergoing cardiac surgery.<h4>Design</h4>Systematic review and meta-analysis.<h4>Data sources</h4>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.<h4>Trial selection</h4>Published and unpublished randomised controlled trials comparing a restrictive with liberal transfusion threshold and that included patients with cardiovascular disease.<h4>Data extraction and synthesis</h4>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.<h4>Main outcome measures</h4>30 day mortality, and cardiovascular events.<h4>Results</h4>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%).<h4>Conclusions</h4>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.<h4>Registration</h4>PROSPERO CRD42014014251.