Does Tranexamic Acid Reduce the Blood Loss in Various Surgeries? An Umbrella Review of State-of-the-Art Meta-Analysis

Background: Tranexamic acid (TXA) has been applied in various types of surgery for hemostasis purposes. The efficacy and safety of TXA are still controversial in different surgeries. Guidelines for clinical application of TXA are needed. Materials and method: We systematically searched multiple medical databases for meta-analyses examining the efficacy and safety of TXA. Types of surgery included joint replacement surgery, other orthopedic surgeries, cardiac surgery, cerebral surgery, etc. Outcomes were blood loss, blood transfusion, adverse events, re-operation rate, operative time and length of hospital stay, hemoglobin (Hb) level, and coagulation function. Assessing the methodological quality of systematic reviews 2 (AMSTAR 2) and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) were used for quality assessment of the included meta-analyses. Overlapping reviews were evaluated by calculating the corrected covered area (CCA). Result: In all, we identified 47 meta-analyses, of which 44 of them were of "high" quality. A total of 319 outcomes were evaluated, in which 58 outcomes were assessed as "high" quality. TXA demonstrates significant hemostatic effects in various surgeries, with lower rates of blood transfusion and re-operation, shorter operative time and length of stay, and higher Hb levels. Besides, TXA does not increase the risk of death and vascular adverse events, but it is a risk factor for seizure (a neurological event) in cardiac surgery. Conclusion: Our study demonstrates that TXA has a general hemostatic effect with very few adverse events, which indicates TXA is the recommended medication to prevent excessive bleeding and reduce the blood transfusion rate. We also recommend different dosages of TXA for different types of adult surgery. However, we could not recommend a unified dosage for different surgeries due to the heterogeneity of the experimental design. Systematic Review Registration: clinicaltrials.gov/, identifier CRD42021240303.

Antifibrinolytic therapy for preventing oral bleeding in people on anticoagulants undergoing minor oral surgery or dental extractions

BACKGROUND

Individuals on continuous treatment with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs) are at increased risk of bleeding complications during and after oral or dental procedures. Anticoagulant treatment is preferably continued at the same dose, since dose reduction or discontinuation of treatment is associated with an increased risk of thromboembolism. The use of haemostatic measures during or after the procedure (or both) could enable continuation of the oral anticoagulant treatment.

OBJECTIVES

We aimed to assess the efficacy of antifibrinolytic agents for preventing bleeding complications in people on oral anticoagulants undergoing minor oral surgery or dental extractions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Coagulopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. We searched PubMed, Embase and the Cochrane Library. Additional searches were performed using ClinicalTrials.gov, the International Clinical Trials Registry Platform (ICTRP), the CINAHL database of nursing and allied health services, the open access ProQuest dissertation database, papers and reports from the American College of Clinical Pharmacy (ACCP) and abstract books from annual scientific conferences.Date of last search: 04 January 2018.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in people on continuous treatment with VKAs or DOACs undergoing oral or dental procedures using antifibrinolytic agents (tranexamic acid (TXA) or epsilon aminocaproic acid) to prevent perioperative bleeding compared to no intervention or usual care with or without placebo.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the titles and abstracts of all identified articles. Full texts were obtained from potentially relevant abstracts and two authors independently assessed these for inclusion based of the selection criteria. A third author verified trial eligibility. Two authors independently performed data extraction and risk of bias assessments using standardized forms. The quality of the evidence was assessed using GRADE.

MAIN RESULTS

No eligible trials in people on continuous treatment with DOACs undergoing oral or dental procedures were identified.Three randomised trials and one quasi-randomised trial (follow-up in all was seven days) in people on continuous treatment with VKAs were included with a total of 253 participants (mean age 60 years). Two trials published in 1989 and 1993 compared the antifibrinolytic agent TXA with placebo in people using VKAs. Two other trials were published in 1999 and 2015 and compared TXA with gelatin sponge and sutures, and dry gauze compression, respectively. In all included trials, those who were treated with VKAs had international normalised ratio (INR) values within the therapeutic range and TXA was applied locally, not systemically.The two trials from 1989 and 1993 comparing TXA with placebo showed a statistically significant beneficial effect regarding the number of major postoperative bleeding episodes requiring intervention, with a pooled risk difference (RD) of -0.25 (95% confidence interval (CI) -0.36 to -0.14) (128 participants) (moderate-quality evidence). For the two trials that compared TXA with either gelatin sponge and sutures or with dry gauze compression, there was no difference between the TXA and the standard care group, RD 0.02 (95% CI -0.07 to 0.11) (125 participants) (moderate-quality evidence). The combined RD of all included trials was -0.13 (95% CI -0.30 to 0.05) (moderate-quality evidence). There were no side effects of antifibrinolytic therapy that required treatment withdrawal (128 participants) (moderate-quality evidence). Despite heterogeneity between trials with respect to the different haemostatic measures used in the control groups, the trials were comparable regarding design and baseline participant characteristics.Overall, we considered the risk of bias to be low in the trials comparing TXA with placebo and moderate in the trials comparing TXA with alternative haemostatic measures.

AUTHORS' CONCLUSIONS

Based on the results of this Cochrane Review, there seems to be a beneficial effect of locally applied TXA in preventing oral bleeding in people on continuous treatment with VKAs undergoing minor oral surgery or dental extractions. However, the small number of identified randomised controlled trials, the relatively small number of participants included in the trials and the differences in standard therapy and treatment regimens between trials, do not allow us to conclude definite efficacy of antifibrinolytic therapy in this population.We were unable to identify any eligible trials in people on continuous treatment with DOACs undergoing oral or dental procedures. Therefore, a beneficial effect of antifibrinolytic therapy can currently only be assumed based on data from the people using VKAs.