Abstract
BACKGROUND: Tranexamic acid (TXA) is recommended for reducing blood loss and transfusion in cardiac surgery. However, there are concerns regarding the safety profile of TXA, especially its proconvulsant effects. We conducted this study to investigate the efficacy and safety of tranexamic acid in cardiac surgery. METHODS: We searched PubMed, Embase and Cochrane Central Register of Controlled Trials from inception to December 11, 2024. Randomised controlled trials assessed the hemostatic effects of TXA in cardiac surgery were included. Two authors independently selected studies and assessed the quality of eligible trials. The main endpoints were red blood cell transfusion and thrombotic outcomes. The results were calculated with pairwise and network meta-analysis. RESULTS: Data was provided by 18,141 participants from 64 trials. High-dose continuous (OR: 0.38, 95%CI: [0.31, 0.47]), low-dose continuous (OR: 0.44, 95%CI: [0.34, 0.56]), high-dose single (OR: 0.50, 95%CI: [0.43, 0.57]), and low-dose single (OR: 0.52, 95%CI: [0.40, 0.67]) TXA significantly reduce the rate of red blood cell transfusion. Furthermore, in high-risk patients, high-dose continuous administration further reduces transfusion risk compared to low-dose continuous administration (OR: 1.22, 95%CI: [1.01, 1.75]). Topical TXA does not significantly reduce the rate of red blood cell transfusion (OR: 0.80, 95%CI: [0.60, 1.07]); conversely, it is associated with a higher rate of red blood cell transfusion compared to intravenous administration. Both intravenous and topical TXA administration reduce postoperative blood loss. High-dose continuous administration further reduces the risk of reoperation (OR: 1.70, 95%CI: [1.03, 2.80]) and the need for fresh frozen plasma transfusion (OR: 1.33, 95%CI: [1.01, 1.74]) compared to low-dose continuous administration. Neither intravenous nor topical TXA increases the incidence of postoperative thrombotic complications. High-dose single administration is associated with a significantly increased risk of postoperative seizures (OR: 6.66, 95%CI: [1.85, 24.02]). CONCLUSIONS: This meta-analysis further confirms that intravenous TXA administration, regardless of dose or administration regimen, significantly reduces postoperative blood loss and red blood cell transfusions in adult cardiac surgery, without increasing the incidence of serious adverse events except for seizures. Future studies should incorporate patient-specific factors, comorbidities, and bleeding risks to determine the optimal TXA dosing strategy that balances risks and benefits. TRIAL REGISTRATION: Our prespecified protocol was registered with PROSPERO (CRD42022380404). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-025-03365-8.