A landmark clinical trial published in the New England Journal of Medicine found that tranexamic acid reduced transfusions across major surgeries without increasing the risk of dangerous blood clots, according to a June 10 announcement. The trial was sponsored and coordinated by the University of Manitoba and co-led by researchers at the University of Manitoba and The Ottawa Hospital.
Tranexamic acid is an inexpensive drug that prevents excessive bleeding and stabilizes blood clots. It has been used in cardiac and some orthopedic surgeries for over 30 years, but doctors have been uncertain if it can safely be used in other major surgeries, especially cancer surgeries.
The pan-Canadian clinical trial studied over 8,000 major surgeries to determine if tranexamic acid reduced bleeding and blood transfusion without increasing the risk of clots. The results support expanding its use to all major surgeries where patients face a high risk of blood loss. Major surgery includes procedures of the head, chest, abdomen, or pelvis that typically require general anesthetic and a hospital stay. For these types of surgery, more than one in 20 patients will need a blood transfusion.
"If tranexamic acid is universally adopted across major surgeries, it will improve surgical safety for millions of patients around the world. In Canada alone, adopting this drug across the board could reduce the number of patients who need a transfusion by 25 per cent annually and reduce the number of blood units required by 10 per cent," said Dr. Daniel McIsaac, co-first author and anesthesiologist at The Ottawa Hospital.
Universal adoption also has potential cost savings. "One transfusion in Canada costs more than $700 CAD compared to under $10 for tranexamic acid. We estimate that routine adoption ... could save 50,000 units of blood each year in Canada and millions ... around the world; the savings to health-care systems will be profound," said Dr. Ryan Zarychanski, trial chair at University of Manitoba.
The study analyzed data from 8,273 major surgeries performed at ten Canadian hospitals between February 2022 and March 2024 using a cluster-crossover design where hospitals alternated between treating with tranexamic acid or placebo every four weeks for about two years. Researchers found that 7.4 percent who received tranexamic acid needed transfusions compared to 9.8 percent with placebo; importantly, there was no increase in venous clotting events (2.1 percent rate) within ninety days after surgery for either group.
About sixty percent—or roughly five thousand—of participants had cancer-related surgery; even among these higher-risk individuals, there was no increased clotting risk from using tranexamic acid during their operations.
"We hope our findings will reassure care providers that this drug is safe and effective at reducing bleeding, and remove a barrier to its use in most major surgeries," said Dr. Dean Fergusson, co-senior author at The Ottawa Hospital.
