Abstract
BACKGROUND: Tranexamic acid (TXA) is widely used to reduce perioperative bleeding and transfusion requirements; however, its optimal dosing, efficacy, and safety remain uncertain, particularly in cardiac surgery patients. METHODS: This single-center, retrospective before-and-after study consecutively included adult patients who underwent cardiac and/or thoracic aortic surgery with cardiopulmonary bypass between 2011 and 2024. Patients were categorized into the before-TXA and after-TXA groups based on the implementation of a routine intraoperative low-dose TXA protocol in December 2017. This protocol included a loading dose (5 mg/kg) drawn from a 500 mg ampoule and administered at anesthesia induction, with the remaining dose added to the CPB priming volume. A maintenance infusion was administered at 5 mg/kg/h throughout surgery. The primary outcome was chest tube output during the first 12 h after surgery. Secondary safety outcomes included thrombotic complications and postoperative seizures. Outcomes were compared using interrupted time series analysis after stabilized inverse probability of treatment weighting. RESULTS: A total of 4,425 patients were analyzed (2,131 in the before-TXA group and 2,294 in the after-TXA group). The median (interquartile range) chest tube output during the first 12 h postoperatively was 480 mL (270-860 mL) in the before-TXA group and 400 mL (230-710 mL) in the after-TXA group. In the interrupted time series analysis, the intercept of log-transformed monthly chest tube output significantly decreased after TXA implementation (β(2) = -0.285; 95% confidence interval, -0.392 to -0.178). There was no significant increase in thrombotic complications or postoperative seizures following intraoperative TXA implementation. CONCLUSIONS: The routine implementation of low-dose intraoperative TXA in cardiac surgery was associated with a significant reduction in bleeding after cardiac surgery, without an increased risk of thrombotic complications or seizures.