Restrictive versus liberal red blood cell transfusion for cardiac surgery: a systematic review and meta-analysis of randomized controlled trials
Patients undergoing cardiac surgery are among the most common recipients of allogeneic red blood cell (RBC) transfusions. However, whether restrictive RBC transfusion strategies for cardiac surgery achieve a similar clinical outcome in comparison with liberal strategies remains unclear. We searched electronic databases from inception to December 2017 for randomized controlled trials (RCTs). We calculated the risk ratios (RRs) and weighted-mean difference (MD) using a random-effects model. We included 9 RCTs with a total of 9005 patients. There was no significant difference in mortality between groups [RR 1.03; 95% confidence interval (CI) 0.74–1.45; P = 0.86]. In addition, there were no significant differences between groups in the clinical outcomes of infections (RR 1.09; 95% CI 0.94–1.26; P = 0.26), stroke (RR 0.98; 95% CI 0.72–1.35; P = 0.91), respiratory morbidity (RR 1.05; 95% CI 0.89–1.24; P = 0.58), renal morbidity (RR 1.02; 95% CI 0.94–1.09; P = 0.68), myocardial infarction (RR 1.00; 95% CI 0.80–1.24; P = 0.99), cardiac arrhythmia (RR 1.05; 95% CI 0.88–1.26; P = 0.56), gastrointestinal morbidity (RR 1.93; 95% CI 0.81–4.63; P = 0.14), or reoperation (RR 0.90; 95% CI 0.67–1.20; P = 0.46). There was a significant difference in the intensive care unit length of stay (h) (MD 4.29; 95% CI 2.19–6.39, P < 0.01) favoring the liberal group. However, there was no significant difference in the hospital length of stay (days) (MD 0.15; 95% CI − 0.18 to 0.48; P = 0.38). In conclusion, this meta-analysis showed that restrictive strategies for RBC transfusion are as safe as liberal strategies in patients undergoing cardiac surgery with regards to short-term clinical outcomes.
KeywordsCardiac surgery Red blood cell transfusion Restrictive Meta-analysis
We would like to thank Katherine Negele, Editorial Assistant, Research Department, Hurley Medical Center, for assistance with manuscript editing.
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Conflict of interest
Dr. Mustafa Hassan has received a Research Grant from Abbott. Dr. Deepak L. Bhatt discloses the following relationships—Advisory Board: Cardax, Elsevier Practice Update Cardiology, Medscape Cardiology, Regado Biosciences; Board of Directors: Boston VA Research Institute, Society of Cardiovascular Patient Care, TobeSoft; Chair: American Heart Association Quality Oversight Committee; Data Monitoring Committees: Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute, for the PORTICO trial, funded by St. Jude Medical, now Abbott), Cleveland Clinic, Duke Clinical Research Institute, Mayo Clinic, Mount Sinai School of Medicine, Population Health Research Institute; Honoraria: American College of Cardiology (Senior Associate Editor, Clinical Trials and News, ACC.org; Vice-Chair, ACC Accreditation Committee), Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute; RE-DUAL PCI Clinical Trial Steering Committee funded by Boehringer Ingelheim), Belvoir Publications (Editor in Chief, Harvard Heart Letter), Duke Clinical Research Institute (Clinical Trial Steering Committees), HMP Global (Editor in Chief, Journal of Invasive Cardiology), Journal of the American College of Cardiology (Guest Editor; Associate Editor), Population Health Research Institute (COMPASS Clinical Trial Steering Committee funded by Bayer), Slack Publications (Chief Medical Editor, Cardiology Today’s Intervention), Society of Cardiovascular Patient Care (Secretary/Treasurer), WebMD (CME Steering Committees); Other: Clinical Cardiology (Deputy Editor), NCDR-ACTION Registry Steering Committee (Chair), VA CART Research and Publications Committee (Chair); Research Funding: Abbott, Amarin, Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Chiesi, Eisai, Ethicon, Forest Laboratories, Idorsia, Ironwood, Ischemix, Lilly, Medtronic, PhaseBio, Pfizer, Regeneron, Roche, Sanofi Aventis, Synaptic, The Medicines Company; Royalties: Elsevier (Editor, Cardiovascular Intervention: A Companion to Braunwald’s Heart Disease); Site Co-investigator: Biotronik, Boston Scientific, St. Jude Medical (now Abbott), Svelte; Trustee: American College of Cardiology; Unfunded Research: FlowCo, Merck, Novo Nordisk, PLx Pharma, Takeda. The remaining authors declare that they have no conflict of interest.
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