ObjectiveTo evaluate the blood protective effect of tranexamic acid on cardiopulmonary bypass in adult congenital heart disease patients. MethodsThere were 84 patients (37 males, 47 females) with congenital heart disease under-going extracorporeal circulation, aged from 18 to 50 years in iur hospital from June through December 2015. All patients were divided into two groups include a control group (group A) with 35 patients and a tranexamic acid group (group B) with 49 patients. After induction of anesthesia, the group B was given tranexamic acid 1 g, and then at rate of 400 mg/h continuous infusion till the end of operation. The group A was given equal volume of physiological saline. Before and after operation and withdrawing of the drainage, the levels of hemoglobin (Hb), platelet (PLt) and international normalized ratio (INR) were tested by taking the central venous blood samples. Chest tube drainage volume, use of red blood cells and plasma after opera-tion were recorded. ResultsNo statistical difference was found between the two groups in Hb, PLT, or INR before opera-tion and usage of blood after operation (P>0.05). Compared with the group A, postoperative chest tube drainage, the use of plasma were lower (P<0.05) in the group B. There was a statistical difference between two groups in Hb, PLT, INR after operation, and withdrawing of the drainage (P<0.05), respectively, while no statistical difference in PLT at withdrawing of drainage was foud. No in-hospital mortality or postoperative complication occurred. ConclusionTranexamic acid has protective effest on blood in adult patients with congenital heart disease undergoing cardiac surgery under cardiopulmonary bypass.