RESUMO
BACKGROUND: Tranexamic acid reduces blood loss in surgery and the risk of death in trauma patients. Meta-analyses of small trials suggest that tranexamic acid decreases the number of deaths from gastrointestinal bleeding, but these meta-analyses are prone to selection bias. OBJECTIVE: The trial provides reliable evidence of the effect of tranexamic acid on mortality, rebleeding and complications in significant acute gastrointestinal bleeding. DESIGN: A multicentre, randomised, placebo-controlled trial and economic analysis. Patients were assigned by selecting one treatment pack from a box of eight, which were identical apart from the pack number. Patients, caregivers and outcome assessors were masked to allocation. The main analyses were by intention to treat. SETTING: The setting was 164 hospitals in 15 countries, co-ordinated from the London School of Hygiene & Tropical Medicine. PARTICIPANTS: Adults with significant upper or lower gastrointestinal bleeding (n = 12,009) were eligible if the responsible clinician was substantially uncertain about whether or not to use tranexamic acid. The clinical diagnosis of significant bleeding implied a risk of bleeding to death, including hypotension, tachycardia or signs of shock, or urgent transfusion, endoscopy or surgery. INTERVENTION: Tranexamic acid (a 1-g loading dose over 10 minutes, then a 3-g maintenance dose over 24 hours) or matching placebo. MAIN OUTCOME MEASURES: The primary outcome was death due to bleeding within 5 days of randomisation. Secondary outcomes were all-cause and cause-specific mortality; rebleeding; need for endoscopy, surgery or radiological intervention; blood product transfusion; complications; disability; and days spent in intensive care or a high-dependency unit. RESULTS: A total of 12,009 patients were allocated to receive tranexamic acid (n = 5994, 49.9%) or the matching placebo (n = 6015, 50.1%), of whom 11,952 (99.5%) received the first dose. Death due to bleeding within 5 days of randomisation occurred in 222 (3.7%) patients in the tranexamic acid group and in 226 (3.8%) patients in the placebo group (risk ratio 0.99, 95% confidence interval 0.82 to 1.18). Thromboembolic events occurred in 86 (1.4%) patients in the tranexamic acid group and 72 (1.2%) patients in the placebo group (risk ratio 1.20, 95% confidence interval 0.88 to 1.64). The risk of arterial thromboembolic events (myocardial infarction or stroke) was similar in both groups (0.7% in the tranexamic acid group vs. 0.8% in the placebo group; risk ratio 0.92, 95% confidence interval 0.60 to 1.39), but the risk of venous thromboembolic events (deep-vein thrombosis or pulmonary embolism) was higher in tranexamic acid-treated patients than in placebo-treated patients (0.8% vs. 0.4%; risk ratio 1.85, 95% confidence interval 1.15 to 2.98). Seizures occurred in 38 patients who received tranexamic acid and in 22 patients who received placebo (0.6% vs. 0.4%, respectively; risk ratio 1.73, 95% confidence interval 1.03 to 2.93). In the base-case economic analysis, tranexamic acid was not cost-effective and resulted in slightly poorer health outcomes than no tranexamic acid. CONCLUSIONS: Tranexamic acid did not reduce death from gastrointestinal bleeding and, although inexpensive, it is not cost-effective in adults with acute gastrointestinal bleeding. FUTURE WORK: These results caution against a uniform approach to the management of patients with major haemorrhage and highlight the need for randomised trials targeted at specific pathophysiological processes. LIMITATIONS: Although this is one of the largest randomised trials in gastrointestinal bleeding, we cannot rule out a modest increase or decrease in death due to bleeding with tranexamic acid. TRIAL REGISTRATION: Current Controlled Trials ISRCTN11225767, ClinicalTrials.gov NCT01658124 and EudraCT 2012-003192-19. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 58. See the NIHR Journals Library website for further project information.
Acute gastrointestinal bleeding (bleeding from the gut) is a common emergency and an important cause of death and illness worldwide. In the UK, more than 65,000 people each year are admitted to hospital because of acute gastrointestinal bleeding; approximately 10% of them die within 30 days. Gastrointestinal bleeding is also common in low- and middle-income countries. The care of patients with gastrointestinal bleeding has improved in recent decades, but death rates remain high. Gastrointestinal bleeding is often caused by stomach ulcers, but also by liver damage owing to alcohol or hepatitis C infection. An effective and affordable treatment for gastrointestinal bleeding could save many lives and may reduce the need for blood transfusions, which is important because blood is a scarce resource in some health-care settings. Tranexamic acid, also known as TXA, is a cheap drug that reduces bleeding in other conditions. It helps blood to clot, thereby decreasing bleeding. A trial in bleeding accident victims found that tranexamic acid reduced the chances of bleeding to death, without any increase in side effects. We wanted to find out if tranexamic acid safely improves outcomes in patients with gastrointestinal bleeding, particularly to prevent deaths. To investigate this, the HALT-IT (Haemorrhage ALleviation with Tranexamic acid Intestinal system) trial studied 12,009 patients with significant gastrointestinal bleeding in 164 hospitals across 15 countries. Half of the patients received tranexamic acid and the other half received a dummy drug, called a placebo. The treatments were assigned randomly and given in addition to all other treatments needed. Neither the patient nor the doctor knew which treatment a patient received. The trial showed that tranexamic acid did not reduce deaths from gastrointestinal bleeding. Instead, tranexamic acid was linked to an increased risk of complications, including unwanted blood clots (such as deep-vein thrombosis) and seizures. The economic analysis indicated that giving tranexamic acid to patients with gastrointestinal bleeding does not represent value for money for the NHS.