Intravenous Tranexamic Acid Decreases Blood Transfusion in Off-Pump Coronary Artery Bypass Surgery: A Meta-analysis

Background: Tranexamic acid (TXA) has been widely used during on-pump coronary artery bypass graft (CABG) surgery owing to its antifibrinolytic effect. However, the efficacy and safety of TXA in off-pump CABG surgery remains unconfirmed, especially intravenous (IV) administration. Objective: The aim of this study was to evaluate the effectiveness and safety of IV administration of TXA in off-pump CABG settings. Methods and Results: A comprehensive literature search was performed to identify randomized controlled trials (RCTs) that compared IV use of TXA with placebo in the reduction of postoperative 24-hour blood transfusion, as well as postoperative death and thrombotic events. The combined estimations were compiled with a fixed-effects model or, if heterogeneity existed, a random-effects model. Funnel plots and Egger's test were used to assess potential publication bias. Subgroup analyses were used to explore possible sources of heterogeneity. In total, 12 RCTs met the inclusion criteria. IV administration of TXA significantly reduced the risk of packed red blood cell (PRBC) transfusion [risk ratio (RR) = 0.61, 95% confidence interval (CI) 0.503 to 0.756, P < .001, I-2 = 0.0%) during the 24 hours after surgery. However, there was no statistical significance in platelet (RR = 0.613, 95% CI 0.112 to 3.348, P = .572, I-2 = 0.0%) or total fresh frozen plasma (FFP) (RR = 0.511, 95% CI 0.246 to 1.063, P = .073, I-2 = 0.0%) transfusion. Also, no significant difference was found in major adverse events (death or thrombotic complications) (RR = 0.917, 95% CI 0.532 to 1.581, P = .756, I-2 = 0.0%) between the 2 groups. Interestingly, further subgroup analysis demonstrated that IV TXA decreased the risk of prothrombin time (PT)- and international normalized ratio (INR)-guided FFP transfusion (RR = 0.462, 95% CI 0.296 to 0.721, P = .001, I-2 = 0.0%). Conclusion: IV TXA was effective in reducing allogeneic blood component transfusion (PRBCs and PT- or INR-guided FFP transfusion), without increasing the incidence of postoperative death or thrombotic complications in off-pump CAB surgery.