Tranexamic Acid in Combination With Vancomycin or Gentamicin Has a Synergistic Effect Against Staphylococci

Is tranexamic acid appropriate for all patients undergoing high-risk surgery?

PURPOSE OF REVIEW

Tranexamic acid (TXA), an antifibrinolytic agent, reduces surgical bleeding in a variety of procedures, such as cardiac, orthopedic, abdominal, and urologic surgery, cesarean section, and neurosurgery. However, there are surgical interventions for which its use is not yet widespread, and some caution persists because of concerns regarding thrombotic risk. The purpose of this review is to analyze the most recent evidence in various subgroups of surgical specialties and the association of TXA with thrombotic events and other side effects (e.g. seizures).

RECENT FINDINGS

Recent clinical trials and meta-analyses have shown that the efficacy and safety vary according to the clinical context, timing of administration, and dose. Some reports found that TXA reduces major bleeding by 25% without a significant increase in thrombotic events.

SUMMARY

Wider use of TXA has the potential to improve surgical safety, avoid unnecessary blood use, and save healthcare funds.

Does Combined Treatment with Tranexamic Acid and Vancomycin Affect Human Chondrocytes In Vitro?

Background: The aim of our study was to examine the combined effects of tranexamic acid (TXA) and vancomycin powder (VP) on chondrocytes in vitro. Despite the use of TXA and VP being linked to a reduced risk of extensive postoperative blood loss and periprosthetic joint infections (PJIs) in TKA, the possible cytotoxic side effects on periarticular cell types remain unclear. Methods: Human chondrocytes were harvested from hyaline cartilage and expanded in monolayer culture before being simultaneously exposed to different concentrations of TXA and VP for varying exposure times. Cell viability and proliferation were assessed using an ATP assay and an Annexin 5 assay, respectively, while changes in the relative expression of chondrogenic marker genes were examined using semiquantitative RT-PCR. Results: The simultaneous exposure of chondrocytes to TXA and VP for more than 48 h led to a reduction in both cell viability and proliferation rates. When exposing chondrocytes to the lowest examined concentrations of both TXA (10 mg/mL) and VP (3 mg/mL), the observed effects were delayed until 96 h. However, our study found no dependencies of the observed effects on the concentrations tested. Further, we found no effects on the expression of chondrogenic marker genes. Conclusions: Consequently, limiting the exposure time of chondrocytes to TXA and VP in an in vitro setting to 24 h may be considered safe and could help to further improve the understanding of the safe use of substances in vivo. However, further in vitro research is required to develop a comprehensive understanding of the effects of both VP and TXA on important periarticular cell types in TKA, including chondrocytes, osteocytes, and tenocytes.

The role of tranexamic acid for infection prevention after fracture fixation

Despite the measures employed, fracture-related infections remain a concern after fracture fixation worldwide. Recently, the role of tranexamic acid as a protective drug against postsurgical infections in joint replacement and orthopedic trauma surgery has been proposed, where tranexamic acid has been associated with less surgical wounds complications and infectious complications including periprosthetic joint infection. The mechanism through which tranexamic acid exerts a protective effect against peri-implant infection is still the subject of debate. Although some authors hypothesize an indirect effect inhibiting the formation of postoperative hematoma, there are several studies that show a direct antibacterial effect of the drug against the capacity of bacterial aggregation, even avoiding biofilm formation, favoring the immune response of the host and the action of antibiotics. The purpose of this narrative review is to show the current role of tranexamic acid in orthopedic trauma, specifically its relationship with the prevention of infections related to implants.

Tranexamic Acid as a Preventive Strategy Against Periprosthetic Joint Infection in Aseptic Revision Arthroplasty: A Comprehensive Review

Periprosthetic joint infection (PJI) is a severe complication following joint replacement surgeries, particularly in aseptic revision arthroplasty, where infection rates are higher compared to primary procedures. The extended surgical time, increased blood loss, and the presence of scar tissue contribute to the higher susceptibility to PJI in revision surgeries. Tranexamic acid (TXA), a synthetic antifibrinolytic agent, is widely used in orthopaedic surgery to reduce intraoperative and postoperative bleeding. By stabilising blood clots and reducing the need for blood transfusions, TXA improves patient outcomes and reduces complications related to excessive bleeding. Emerging evidence suggests that TXA may also play a role in reducing PJI, as minimising bleeding and haematoma formation can reduce bacterial colonisation and blood transfusions are associated with increased infection risks due to immunomodulation. This review explores the potential of TXA as a preventive strategy against PJI in aseptic revision arthroplasty, evaluating its mechanisms, clinical applications, and current evidence. While TXA's efficacy in reducing blood loss is well-established, its role in infection prevention, particularly through indirect mechanisms such as limiting haematoma formation, warrants further investigation. By incorporating TXA into multimodal strategies aimed at reducing PJI, surgeons can potentially improve patient outcomes and reduce the financial burden on healthcare systems. This review provides a comprehensive examination of the available data on TXA's role in preventing PJI in revision arthroplasty, with an emphasis on understanding its mechanisms and identifying gaps in current knowledge that require further research.

Association Between Tranexamic Acid and Decreased Periprosthetic Joint Infection Risk in Patients Undergoing Total Hip and Knee Arthroplasty: A Systematic Review and Meta-Analysis of Over 2 Million Patients

BACKGROUND

The purpose of this study was to perform a systematic review and meta-analysis to evaluate the association between tranexamic acid (TXA) use during primary total hip arthroplasty (THA) and primary total knee arthroplasty (TKA), and the risk of developing periprosthetic joint infection (PJI) after these procedures.

METHODS

A systematic review was carried out from inception to October 17, 2022. There were 6 studies that were ultimately included in the meta-analysis. The association between the development of PJI and TXA was analyzed using odds ratios (ORs) with 95% confidence intervals (CIs) and estimates of risk difference (RD). Subgroup analysis was performed to evaluate only studies reporting out to 90 days of follow-up versus more than 90 days of follow-up.

RESULTS

Among 2,098,469 arthroplasties, TXA utilization was associated with an overall lower risk of PJI (OR = 0.63 [95% CI 0.42 to 0.96], P < .001) and a 0.4% lower incidence of PJI (RD = -0.0038, 95% CI [-0.005 to -0.002], P < .001). When subgrouping the studies according to length of follow-up, TXA was associated with a lower risk of PJI (OR = 0.43 [95% CI 0.35 to 0.53], P < .001) and a 1% lower incidence of PJI (RD = -0.0095 [95% CI -0.013 to -0.005], P < .001) in patients followed for more than 90 days.

CONCLUSIONS

This meta-analysis demonstrates that TXA use is associated with a reduced risk of PJI, with our RD analysis identifying an approximately 0.4% reduction in PJI rates with TXA use. These findings provide even more data to support the routine use of TXA during primary THA and primary TKA.

Validation of the antibacterial effect of topically applied tranexamic acid using in vitro and in vivo models

Background

Several studies have shown that tranexamic acid (TXA), an antifibrinolytic, reduces postoperative infection rates. Recent in vitro research showed that TXA alone and in combination with vancomycin and gentamicin had a synergistic effect against some staphylococcal strains. In the present study, this synergistic effect was validated in samples from patients with staphylococcal periprosthetic infection (PPI) and in an in vivo model.

Methods

We tested 19 clinical strains (5 Staphylococcus aureus and 14 coagulase-negative staphylococci [CoNS]) against 10 mg/ml TXA alone and in combination with serial dilutions of vancomycin and gentamicin. The standardized microtiter plate method was used. The minimal inhibitory concentration (MIC) were calculated using standard visualization of well turbidity. We also used an S. aureus (ATCC29213) murine subcranial PPI model to compare the synergistic effect of TXA and gentamicin with that of TXA or gentamicin alone after 4 days of monitoring. The mice were euthanized, and disks were removed for analysis of cfu/ml counts and cell viability rate. Biofilm structure of both in vitro and in vivo samples was also analyzed using scanning electron microscopy (SEM).

Results

When TXA was combined with vancomycin or gentamicin, the MIC decreased in 30% of the strains studied. According to species, the MIC50 for vancomycin and gentamicin alone and in combination with TXA against S. aureus strains was the same. This was also the case for CoNS with vancomycin and its corresponding combination, whereas with gentamicin and TXA, a reduction in MIC50 was observed (2 dilutions). In addition, in the in vivo model, the mean (SD) log cfu/ml and cell viability rate obtained from the implant was lower in the group of mice treated with TXA and gentamicin than in those treated only with TXA or gentamicin. SEM images also corroborated our findings in strains in which the MIC was reduced, as well as the in the mice implants, with the area occupied by biofilm being greater in samples treated only with gentamicin or TXA than in those treated with TXA+gentamicin.

Conclusion

We confirm that combining TXA with vancomycin or gentamicin exerts a synergistic effect. However, this only occurs in selected strains.

Fewer severe infections with tranexamic acid in patients with hematologic malignancies

Background

Tranexamic acid (TXA) is an antifibrinolytic agent that reduces bleeding in a multitude of clinical settings from postpartum hemorrhage to trauma. TXA may have clinical effects unrelated to bleeding; plasminogen, the target of TXA, alters immune responses, and TXA appears to decrease the risk of infection in patients undergoing cardiac surgery, as well as joint arthroplasty.

Objectives

To address whether TXA alters rates of infection and inflammatory outcomes in patients with hematologic malignancies.

Methods

We performed a post hoc analysis of outcomes of patients randomized to receive either TXA or placebo in the double-blinded, multicenter American Trial to Evaluate Tranexamic Acid Therapy in Thrombocytopenia (Clinicaltrials.gov identifier: NCT02578901).

Results

TXA did not change the overall rate of infections, but the rate of severe infections (Common Toxicology Criteria for Adverse Events grade 3+) was lower in patients who received TXA compared with the placebo group. Patients who experienced grade 3+ infections had higher rates of World Health Organization grade 2+ bleeding and red blood cell transfusion requirements than patients who did not experience a grade 3+ infection, irrespective of treatment group. TXA did not impact other inflammatory outcomes such as mucositis, rash, or graft vs host disease.

Conclusion

Patients with hematologic malignancies who received TXA had less severe infections than those who received placebo with no difference in overall rate of infection or other inflammatory outcomes. Further investigation is needed on the impact of TXA on infections in this population.

Tranexamic acid for haemostasis and beyond: does dose matter?

Tranexamic acid (TXA) is a widely used antifibrinolytic agent that has been used since the 1960's to reduce blood loss in various conditions. TXA is a lysine analogue that competes for the lysine binding sites in plasminogen and tissue-type plasminogen activator impairing its interaction with the exposed lysine residues on the fibrin surface. The presence of TXA therefore, impairs the plasminogen and tPA engagement and subsequent plasmin generation on the fibrin surface, protecting fibrin clot from proteolytic degradation. However, critical lysine binding sites for plasmin(ogen) also exist on other proteins and on various cell-surface receptors allowing plasmin to exert potent effects on other targets that are unrelated to classical fibrinolysis, notably in relation to immunity and inflammation. Indeed, TXA was reported to significantly reduce post-surgical infection rates in patients after cardiac surgery unrelated to its haemostatic effects. This has provided an impetus to consider TXA in other indications beyond inhibition of fibrinolysis. While there is extensive literature on the optimal dosage of TXA to reduce bleeding rates and transfusion needs, it remains to be determined if these dosages also apply to blocking the non-canonical effects of plasmin.