Use of Oral and Intravenous Tranexamic Acid in Total Knee Arthroplasty and Total Hip Arthroplasty Procedures.

Introduction: Tranexamic acid (TXA) is an antifibrinolytic drug commonly used in total knee arthroplasty (TKA). Intravenous (IV) and topical TXA therapy have been extensively studied and shown to reduce blood loss, length of hospital stay, and blood transfusion rates following TKA. Despite the extensive literature regarding IV and topical TXA in orthopedics, there is a current dearth of studies analyzing oral usage. The primary purpose of this randomized controlled study is to compare post-surgical blood loss with the use of IV and oral TXA following a TKA.

Methods: In this multicenter, prospective, controlled, randomized study, patients were randomized to receive 1.95 grams of oral TXA two hours preoperatively or 15 mg/kg (1 gram max) of IV TXA mixed in 100 mL of normal saline preoperatively. Intraoperatively, each patient received a combination of 500 mg TXA mixed with 25 mL of normal saline injected into the suction drain and clamped for 30 minutes postoperatively. The primary outcome was absolute (g/dL) change in hemoglobin levels at 24 hours postoperatively. Secondary outcomes included a percent change in hematocrit levels and total drain output at 24 hours postoperatively. Power analysis determined that 40 patients were required in each group.

Results: About 24 patients received IV TXA and 14 patients received oral TXA. The mean decrease in hemoglobin 24 hours postoperatively was not greater (p=0.12) with the use of oral TXA compared to IV TXA (1.70 g/dL vs. 2.50 g/dL, respectively). The mean decrease in hematocrit 24 hours postoperatively in the treatment (oral TXA) group was not greater (p=0.18) than the control (IV TXA) group (5.3% vs. 7.0%, respectively). Both changes in hemoglobin and hematocrit resulted in a normal distribution of data and satisfactory one-sided T-test values (p=0.98 and p=0.92, respectively). The mean drain output measured 24 hours postoperatively in the treatment group was significantly (p=0.04) less than the control group (47.5 mL vs. 170 mL, respectively). All tests performed were one-sided T-tests.

Discussion: Compared to IV TXA, we found oral administration to have no significant difference in hemoglobin (p=0.12) or hematocrit (p=0.18) loss. These findings may support the utilization of oral TXA as a valid alternative to the IV route. We found that patients who received oral TXA produced significantly lower drainage output when compared to IV (47.5 mL and 170 mL, respectively; p=0.04). Persistent wound drainage following TKA has been correlated with increased rates of periprosthetic joint infections, residual pain, and reoperation. Further work is needed to assess the effect of postoperative drainage quantity on the recovery of TKA.

Conclusion: Based upon the data gathered, oral TXA does not result in greater loss of hemoglobin or hematocrit within 24 hours following surgery. However, total drain output was significantly less in the oral group after 24 hours following a TKA. With more subjects, we would expect to see the mean values between groups move closer to each other and fit well with the current literature. This suggests that oral TXA is non-inferior to IV TXA when comparing these variables following TKA. Our current study has limitations, including a small sample size and no blinding. Therefore, this study provided a limited quality of evidence. Confirmation with a blinded, randomized controlled trial and meta-analysis is required to report a higher quality of evidence.