Tranexamic acid for upper gastrointestinal bleeding

Abstract

Background. In patients with trauma and significant bleeding or risk of significant bleeding it is advised to administer tranexamic acid (TXA) intravenously as early as possible at a loading dose of 1 g for 10 minutes, followed by 1 g for 8 hours. The effectiveness of TXA has been proven in various pathological conditions in large trials. TXA has been shown to reduce the need for blood transfusions. Objective. To describe the use of TXA for upper gastrointestinal tract (GIT) bleeding. Materials and methods. Analysis of literature sources on this topic. Results and discussion. The mechanism of TXA action is to inhibit plasminogen activation and reduce fibrin degradation, however, its features are not clear. With the use of TXA, the strength of the blood clot and its resistance to lysis increases. The use of TXA in gastrointestinal bleeding was analyzed in the Cochrane Review (2012) of seven randomized controlled trials involving 1,654 patients. TXA was compared with placebo, lansoprazole or cimetidine. There was a lower mortality in the TXA group, however, after taking into account possible bias, this trend did not persist. A randomized placebo-controlled study of HALT-IT included 12,009 patients with gastrointestinal bleeding who were prescribed TXA (loading dose of 1+3 g for 24 hours) or placebo. The primary endpoint was death from bleeding within 5 days. There were no differences in mortality or re-bleeding. The TXA group had a higher frequency of deep vein thrombosis and pulmonary embolism. One of the reasons for the lack of benefits of TXA in gastrointestinal bleeding is that the onset of such bleeding is difficult to detect immediately, and to achieve the effect of TXA as early as possible administration is necessary. In this case, >80 % of patients sought medical help >3 hours after the onset of bleeding. In addition, in 50 % of patients, the bleeding was due to esophageal varices due to liver disease. It is known that most coagulation factors are synthesized in the liver, so liver failure is a common cause of coagulopathies. When the liver is affected, the levels of vitamin-K-dependent procoagulants (coagulation factors II, VII, IX and X), coagulation factor V, as well as anticoagulants (proteins C and S, antithrombin) decrease. Levels of fibrinogen and acute phase proteins remain normal or increase. In case of liver failure, hyperfibrinolysis occurs and at the same time the risk of thrombosis increases significantly. In such patients there is a decrease in hemostatic blood reserve. In general, contraindications to the use of TXA include severe renal failure, seizures, disseminated intravascular coagulation without bleeding, arterial or venous thromboembolism, active bleeding from the upper urinary tract. Conclusions. 1. TXA is effective for most types of bleedings, however, there are some exceptions. 2. One should remember the side effects of TXA and follow the recommended method of administration. 3. TXA is not suitable for the treatment of gastrointestinal bleeding.