Intravenous tranexamic acid in arthroscopic rotator cuff repair in the lateral decubitus position: a retrospective cohort study

Background Arthroscopic rotator cuff repair (ARCR) is a standard procedure for shoulder pathologies; however, intraoperative bleeding often compromises visual clarity, thereby prolonging operative time and increasing irrigation fluid usage. The hemostatic efficacy of intravenous tranexamic acid (TXA) in shoulder arthroscopy remains controversial. A recent randomized controlled trial (RCT) in the lateral decubitus position found no clear improvement in visual clarity with TXA. This retrospective cohort study aimed to describe the associations between intravenous TXA use and intraoperative and early postoperative outcomes in patients undergoing ARCR in the lateral decubitus position, generating hypotheses for future trials. Methods A retrospective cohort study was conducted on 118 patients who underwent ARCR in the lateral decubitus position at our institution between January 2024 and January 2025. Patients were divided into a TXA group ( n = 59) and a control group ( n = 59) based on whether intravenous TXA was administered at the surgeon’s discretion. The TXA group received a 1 g intravenous infusion of TXA (diluted in 100 mL normal saline) 10 min before skin incision, while the control group received no hemostatic agent. All surgeries utilized a gravity-fed irrigation system with a standardized fluid height of 100 cm. The primary outcome was intraoperative visual clarity assessed via a visual analogue scale (VAS) by the operating surgeon, who was not blinded. Secondary outcomes included operative time, estimated blood loss (EBL), irrigation fluid volume, 24-hour postoperative hemoglobin (Hb) drop, 24-hour resting pain VAS, and 30-day complications. Statistical analyses employed independent t-tests, chi-square tests, and multivariate linear regression. No a priori sample size calculation was performed. Results The TXA group demonstrated significantly higher intraoperative visual clarity VAS scores compared to the control group (8.9 ± 1.1 vs. 7.3 ± 1.4; mean difference 1.6, 95% CI : 1.1 to 2.1; P < 0.001). The TXA group also exhibited shorter operative time (68.2 ± 12.5 vs. 79.7 ± 14.3 min, P < 0.001), lower EBL (15.6 ± 4.8 vs. 22.4 ± 5.3 mL, P < 0.001), reduced irrigation fluid consumption (12.6 ± 1.9 vs. 15.4 ± 2.6 L, P < 0.001), smaller 24-hour Hb decline (7.2 ± 2.6 vs. 10.5 ± 3.1 g/L, P < 0.001), and lower 24-hour resting pain scores (3.2 ± 1.1 vs. 4.5 ± 1.3, P < 0.001). Multivariate regression confirmed TXA use as an independent factor associated with improved visual clarity ( β = 1.56, P < 0.001). No deep vein thrombosis, pulmonary embolism, or infections occurred in either group; however, systematic screening for thromboembolism was not performed. The incidence of moderate-to-severe joint swelling was comparable between groups (5.1% vs. 8.5%, P = 0.717). Conclusion In this selected retrospective cohort, intravenous TXA use was associated with improved visual clarity, shorter operative time, and reduced blood loss and irrigation volume in lateral-decubitus ARCR. However, due to the non-randomized, unblinded design, these findings should be considered hypothesis-generating rather than evidence of a causal effect. Randomized trials with objective, blinded assessment of visualization, standardized anesthetic and surgical protocols, and longer follow-up are needed. Clinical trial number not applicable.