Tehran University of Medical Sciences Journal of Orthopedic and Spine Trauma 2538-2330 10 1 2024 04 01 9 14 Reza Zandi https://orcid.org/0000 0002 0095 6745 Alireza Manafi-Rasi http://orcid.org/0000-0001-6355-704X Mohammadreza Minator Sajjadi https://orcid.org/0000 0003 2081 7619 Esmaeel Yousefi-Hajivand https://orcid.org/0000-0002-9337-0662 2023 06 06 2024 03 13 Background: Despite their low incidence, pelvis and acetabular fractures have a high mortality rate due to extensive hemorrhage. Tranexamic acid (TXA) is an antifibrinolytic drug that inhibits the production of plasminogen. The aim of the current study is to evaluate the safety and efficacy of TXA use for blood loss reduction and the need for blood transfusion in patients with fractures of the pelvis or acetabulum. Methods: 108 patients were recruited from two tertiary care hospitals and assigned evenly either to the intervention (TXA) or the control group. TXA group received 15mg/kg TXA 30 minutes before the fracture reduction and fixation surgery. The number of transfused blood units before, during, and after the surgery was recorded. Blood loss was assessed by calculation of estimated blood loss (EBL), collected blood with drain, collected blood with suction, and weight of the used gauzes during the surgery. The time between fracture occurrence and the surgery, the duration of the surgery, and the days of admission were assessed. Results: The mean age was 39.49 ± 15.81, and 69.4% were female. 6 patients had pelvic, and 102 patients had acetabulum fractures. The duration of the surgery was not significantly different. The time gap between the reconstructive surgery and fracture occurrence was significantly higher in the TXA group (P = 0.032). The mean postoperative hospitalization time was significantly lower among TXA group patients (P = 0.037). The mean hemoglobin in the TXA group was significantly higher, postoperatively (P = 0.028). The mean EBL, the blood volume collected by suction or drain, the weight of the consumed gauze during the surgery, and the number of transfused blood units were significantly lower in the TXA group. The transfusion rate was significantly lower in patients with a shorter time gap between fracture occurrence and reduction surgery (P = 0.021).  Conclusions: TXA can decrease blood loss, the transfused blood units during and after the operation, and hospital admission days. Moreover, it did not increase the chance of pulmonary thromboembolism or deep vein thrombosis in the patients receiving tranexamic acid; thus, it can be assumed as a safe and efficient drug in patients with acetabulum or pelvis fractures. https://jost.tums.ac.ir/index.php/jost/article/view/505 https://jost.tums.ac.ir/index.php/jost/article/download/505/358