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.

Restrictive versus liberal red cell transfusion strategies in patients with acute myocardial infarction: a systematic review and meta-analysis

BackgroundAnemia is frequent in patients with acute myocardial infarction(AMI), and the optimal red blood cell transfusion strategy for patients with AMI and anemia is still controversial. We aimed to compare the efficacy of restrictive and liberal red cell transfusion strategies in patients with AMI and anemia.MethodsWe systematically searched PubMed, EMBASE, Web of Science, Cochrane Library, and Clinicaltrials.gov, from their inception until March 2021. Inclusion criteria were clinical trials that compared the efficacy of restrictive and liberal transfusion strategies in patients with AMI and anemia on all-cause mortality and major adverse cardiovascular events. 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. ResultsThe search yielded a total of 6630 participants in six studies. Among the included patients, the average age ranged from 69.0 to 79.5 years and 2950 (44.5%) were men. A total of 2008 patients received restrictive red blood transfusion while 4622 patients were given liberal red blood transfusion. No difference was found in overall mortality and follow-up mortality between restrictive and liberal blood 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 was associated with 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.ConclusionRestrictive and liberal red blood transfusion have a similar effect on overall mortality and follow-up mortality in patients with AMI and anemia. However, restrictive transfusion was associated with a higher risk of in-hospital mortality compared with liberal transfusion. The findings suggest that transfusion strategy should be evaluated in the more future researches.

Perioperative Transfusion Associated With Increased Morbidity and Mortality in Geriatric Patients Undergoing Hip Fracture Surgery

Introduction: Both conservative and liberal transfusion thresholds, in regard to hematocrit and hemoglobin levels, have been widely studied with varying outcomes. The aim of this study was to evaluate if transfusion administered peri- (anytime during the admission), pre-, intra-, or postoperatively an its association with morbidity and mortality in the geriatric population undergoing hip surgery. Methods: This study was an institutional review board approved retrospective analysis of data collected from 841 patients at a single urban institution who underwent surgical repairs for hip fractures from 2008 to 2010. Results: Our analysis included data from 841 surgical patients. Mean patient age was 83, 74% were female, 48% received spinal anesthesia while 52% underwent general anesthesia. Out of 841 patients, 425 were transfused during the perioperative period. Most transfusions occurred postoperatively. Perioperative, intraoperative and postoperative transfusion was associated with an increase in post-operative AKI. Intraoperative blood transfusion was associated with an increase in morbidity (11.6% increased to 22.2%) by 1.9 fold, AKI (3.9% increased to 11.1%) by 2.8 fold, as well as an increase in mortality (5.2 increased to 15.6%) within 60 days by 3 fold. Conclusions: This may suggest that patients transfused prior to surgery, despite having met a specific trigger hemoglobin level earlier, may have been treated before deteriorating to a point that would cause future systemic implications.