The purpose of the study by Aguilera et al.1 was to assess the clinical effectiveness of two commonly used intraoperative techniques that are currently utilized in total knee arthroplasty to reduce blood loss. These were the application of fibrin glue and the intravenous administration of tranexamic acid. Prospective randomized clinical trials such as this one are critical for clinicians who currently care for patients who are undergoing total knee arthroplasty because often the literature is unclear as to which techniques are most efficacious. Currently, many approaches are utilized to reduce blood loss and the need for transfusions in total knee arthroplasties. These techniques include various electrocautery devices, pharmacological agents, as well as intravenous agents. It has been well-documented within the orthopaedic literature that excessive blood loss has been associated with increased hospital stays, increased complications, increased costs, and decreased patient satisfaction. In addition, the use of allogeneic blood transfusion is not without risk for hypersensitivity reactions and infection. With increased pressures from Medicaid and Medicare to improve quality while reducing costs, there is an increased emphasis on the importance of blood loss studies, such as this one, which attempts to provide Level-I data to help address this quite challenging problem in total knee arthroplasty and to help clinicians make more informed care decisions.
In the current study, 172 patients were randomized and distributed among four groups. The first group received a fibrin product from the Blood and Tissue Bank of Catalonia (Barcelona, Spain). This fibrin glue was obtained from fresh-frozen plasma from two allogeneic donors. The second group received Tissucol (Baxter S.L., Valencia, Spain). This is a topical fibrin glue that is administered at the time of closure and is applied with a spray device. The third group received intravenous tranexamic acid of 1 g fifteen to thirty minutes prior to tourniquet inflation and then 1 g at deflation of the tourniquet during closure. Group 4 was considered the control, and hemostasis was obtained by standard electrocauterization of bleeding points. The primary outcome was blood collected in vacuum drains, but also important, secondary outcomes included the rate of perioperative blood transfusion, the preoperative as well as postoperative hemoglobin level, the number of units of blood that were transfused, the rate of surgical infection, the length of hospital stay, the rate of venous thrombosis, as well as the mortality rate. Their results demonstrated that Group 3 (the tranexamic acid group) had a significant reduction in blood loss compared with the control group and compared with the two fibrin glue groups as well (p < 0.001). Group 3 also had a significant reduction in blood transfusions compared with the other two groups (p = 0.024). None of the experimental groups showed a change compared with the control group in terms of length of hospitalization or rate of complications.
This is another report that confirms multiple other studies that have shown that the use of tranexamic acid can reduce the need for autologous blood transfusion in lower extremity joint arthroplasty2,3. As stated, this is an important topic and these findings are reassuring. It is also important that there was no increase in adverse events including thromboembolic phenomena. One should note that any patients with a history of thromboembolic events were excluded from receiving the tranexamic acid in the present study. This study is similar to one by Kelley et al., who evaluated fifty patients managed with a total knee arthroplasty who received tranexamic acid and compared them with seventy patients who did not and served as controls. The patients who received tranexamic acid had significantly lower blood loss (mean and standard deviation, 373.8 ± 264.6 mL versus 871.6 ± 457.7 mL; p < 0.001) than the controls and significantly higher hemoglobin levels on Days 1 and 2 (p < 0.005), as well as a decreased number of transfused allogeneic blood units (mean and standard deviation, 0.60 ± 0.84 units versus 1.53 ± 1.3 units)3. A Cochrane meta-analysis performed by Tan et al. analyzed 1114 patients who had a total knee arthroplasty in nineteen trials and found substantial reductions in perioperative blood loss and transfusion requirements without increasing the risk of complications when using tranexamic acid4. Similar findings were found in a meta-analysis of nineteen randomized controlled trials of 1030 patients who had a total hip arthroplasty5.
The results for fibrin glue in the study by Aguilera et al. also are similar to those in another study that did not confirm that fibrinogen reduced blood loss in total knee arthroplasty. Heyse et al. evaluated 200 patients undergoing total knee arthroplasty who were randomized into a double-blind clinical trial to receive either intra-articular fibrinogen two minutes before tourniquet release or no treatment6. They found no differences between the groups with regard to postoperative drain output, postoperative hemoglobin decrease, need for transfusions, early range of motion, visual analog scale pain scores, or complications. There are, however, studies that have shown the efficacy of fibrin glue in arthroplasties of lower extremity joints; the difference may be due to a lower dose used in the present study or a different fibrin glue formulation. In addition, some of the formulations used, e.g., Quixil (Ethicon, Johnson & Johnson), contain tranexamic acid, which could have produced a local effect to reduce blood loss7-9. The other limitations of the present study may be the small numbers in each group. Again, it would be nice to have this study performed with much larger numbers and done on a multicenter basis. Nevertheless, despite some limitations, the authors are to be commended for the prospective randomized nature of this work, and we believe that this study is encouraging for surgeons who may want to try using tranexamic acid for reducing postoperative blood loss after total knee arthroplasty.