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Background Most clinical practice guidelines recommend restrictive red cell transfusion practices, with the goal of minimising exposure to allogeneic blood. The purpose of this review is to compare clinical outcomes in patients randomised to restrictive versus liberal transfusion thresholds (triggers). Objectives To examine the evidence for the effect of transfusion thresholds on the use of allogeneic and/or autologous red cell transfusion, and the evidence for any effect on clinical outcomes. Search methods We identified trials by searching: the Cochrane Injuries Group Specialised Register (searched 1 February 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), MEDLINE (Ovid) 1948 to January Week 3 2011, EMBASE (Ovid) 1980 to 2011 (Week 04), ISI Web of Science: Science Citation Index Expanded (1970 to February 2011) and ISI Web of Science: Conference Proceedings Citation Index - Science (1990 to February 2011). We checked reference lists of other published reviews and relevant papers to identify any additional trials. Selection criteria Controlled trials in which patients were randomised to an intervention group or to a control group. We included 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. Data collection and analysis We pooled risk ratios of requiring allogeneic blood transfusion, transfused blood volumes and other clinical outcomes across trials using a random-effects model. Two people performed data extraction and assessment of the risk of bias. Main results We included 19 trials involving a total of 6264 patients and they were similar enough that results could be combined. Restrictive transfusion strategies reduced the risk of receiving a RBC transfusion by 39% (risk ratio (RR) 0.61, 95% confidence interval (CI) 0.52 to 0.72). This equates to an average absolute risk reduction (ARR) of 34% (95% CI 24% to 45%). The volume of RBCs transfused was reduced on average by 1.19 units (95% CI 0.53 to 1.85 units). However, heterogeneity between trials was statistically significant (P < 0.00001; I2 ≥ 93%) for these outcomes. Restrictive transfusion strategies did not appear to impact the rate of adverse events compared to liberal transfusion strategies (i.e. mortality, cardiac events, myocardial infarction, stroke, pneumonia and thromboembolism). Restrictive transfusion strategies were associated with a statistically significant reduction in hospital mortality (RR 0.77, 95% CI 0.62 to 0.95) but not 30-day mortality (RR 0.85, 95% CI 0.70 to 1.03). The use of restrictive transfusion strategies did not reduce functional recovery, hospital or intensive care length of stay. The majority of patients randomised were included in good-quality trials, but some items of methodological quality were unclear. There are no trials in patients with acute coronary syndrome. Authors’ conclusions...

Background-Concerns regarding the safety of transfused blood have prompted reconsideration of the use of allogeneic (from an unrelated donor) red blood cell (RBC) transfusion, and a range of techniques to minimise transfusion requirements.

BackgroundConcerns regarding the safety of transfused blood have led to the development of a range of interventions to minimise blood loss during major surgery. Anti-fibrinolytic drugs are widely used, particularly in cardiac surgery, and previous reviews have found them to be effective in reducing blood loss, the need for transfusion, and the need for re-operation due to continued or recurrent bleeding. In the last few years questions have been raised regarding the comparative performance of the drugs. The safety of the most popular agent, aprotinin, has been challenged, and it was withdrawn from world markets in May 2008 because of concerns that it increased the risk of cardiovascular complications and death. ObjectivesTo assess the comparative effects of the anti-fibrinolytic drugs aprotinin, tranexamic acid (TXA), and epsilon aminocaproic acid (EACA) on blood loss during surgery, the need for red blood cell (RBC) transfusion, and adverse events, particularly vascular occlusion, renal dysfunction, and death.

Trusted evidence. Informed decisions. Better health. Cochrane Database of Systematic Reviews Analysis 3.6. Comparison 3 Cell salvage-blood transfused (active versus control), Outcome 6 Units of allogeneic blood transfused (Active vs Control

Shortages of donor blood and fears of transmitted infections have prompted the use of a range of blood-sparing techniques in the peri-operative period. We conducted a systematic review of three techniques that involve the re-infusion of a patient's blood--pre-operative autologous blood deposit (PAD), acute normovolaemic haemodilution (ANH), and cell salvage (CS). We examined the effects of these interventions on the need for peri-operative allogeneic red blood cell transfusion and on clinical outcomes. Controlled clinical studies were identified by computer searches of comprehensive electronic databases and bibliographic searches of published articles. The literature search retrieved a total of 68 randomized trials (RCTs) and 81 controlled observational studies that included data from over 34 000 individuals. In summary, the RCTs found that autologous transfusion techniques consistently reduced the frequency of allogeneic transfusions, with intervention effect sizes ranging from a relative 63% reduction (95% CI 46-74%) with PAD, to 42% (27-53%) with CS and to 31% (16-44%) with ANH. Non-randomized studies reported larger effect sizes than RCTs. PAD increased overall transfusion rates by 30% (95% CI 12-48%) and reduced pre-operative haemoglobin levels by an average of 1.23 g dL(-1). Intervention effects were substantially reduced when these techniques were performed under transfusion protocols. Interpretation of the studies was hampered by serious methodological weaknesses, particularly inadequate randomization techniques, unblinded measurements and the subjective nature of the outcome variables. The studies reported few clinical outcome and adverse event data. Previous claims regarding reduced rates of mortality and infection with autologous transfusions were not confirmed.

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Background Most clinical practice guidelines recommend restrictive red cell transfusion practices, with the goal of minimising exposure to allogeneic blood (from an unrelated donor). The purpose of this review is to compare clinical outcomes in patients randomised to restrictive versus liberal transfusion thresholds (triggers). Objectives To examine the evidence for the effect of transfusion thresholds on the use of allogeneic and/or autologous blood, and the evidence for any effect on clinical outcomes.