Grant: Project Grant

During open heart surgery patients are at high risk of bleeding due to the extensive tissue damage required in gaining access to and fixing the heart. After surgery, excessive bleeding may be due to the inhibition of normal blood clot formation (coagulation system) or over-active break down of blood clotting (fibrinolytic system). Tranexamic acid (TxA) is a generic medication that blocks the fibrinolytic system, so called anti-fibrinolytics, and is used around the world during heart surgeries to stop or prevent excessive bleeding. TxA is usually given intravenously without issue but a serious side effect-seizures, occurs in about 1% of heart surgery patients-. Patients experiencing a seizure are more likely to have a stroke and stay longer in hospital. The risk of seizures increases with the intravenous TxA dose. Thus seizures can be reduced by lowering the TxA dose but at a lower dose the drug is less effective in preventing bleeding, putting patients at a higher risk for bleeding. In theory, applying TxA more directly to sites of tissue damage (local) rather than broadly to the circulatory system (systemic) should decrease side effects from intravenous TxA (seizures) by decreasing the ability of TxA to reach the brain and decrease the need for RBC transfusions by enhancing the blood-sparing effects of TxA. Results from our previous trial (DEPOSITION pilot) suggest that when TxA is poured over the heart (topical) rather than given intravenously fewer seizures and red blood cell (RBC) transfusions are observed. However, no trial of topical TxA has been large enough to detect significant differences in seizure or RBC transfusion risk. Therefore, we are proposing a large simple randomized controlled trial with minimal paperwork and low costs to properly test the potential of topical TxA for reducing seizures in patients undergoing heart surgery. The results of DEPOSITION are expected to apply to most other surgical disciplines in Canada and around the world.