Effects Of Different Doses Of Tranexamic Acid In Cardiac Surgery Under Cardiopulmonary Bypass

Objective Tranexamic acid (TA) is a synthetic derivate of lysine, and exerts its antifibrinolytic effect through the reversible blockade of lysine-binding sites on plasminogen molecules. TA is commonly used during cardiac surgery with cardiopulmonary bypass (CPB) to prevent excessive blood loss after surgery and to minimize transfusion requirements. However, the optimal dose of TA is still unknown. The study evaluated the blood-saving effects of three different doses of TA during cardiac surgery.Methods The study was a prospective, double-blind, randomized controlled trial. From September 2012 to September 2014,955 consecutive patients aged from 18 to 75 scheduled for elective cardiac surgery with CPB in Fuwai Hospital were enrolled in the study, including coronary artery bypass graft, valvular surgery, non-cyanotic congenital heart diseases, intracardiac tumors, and hypertrophic obstructive cardiomyopathy. Patients were randomly divided into 3 groups:a lower-dose group (loading dose lOmg/kg in 15 minutes, maintenance dose 2mg/kg/h, and a CPB prime dose of 10mg/kg), a morderate-dose group (loading dose 20mg/kg in 15 minutes, maintenance dose 4mg/kg/h, and a CPB prime dose of 20mg/kg), and a higher-dose group (loading dose 30mg/kg in 15 minutes, maintenance dose 6mg/kg/h, and a CPB prime dose of 30mg/kg). TA was given when the surgery begain. The amount of chest tube drainage in 6 hours and 24 hours were recorded. Other measurements included the amount and frequency of allogenic transfusion, and morbidities within 7 days after surgery.Results There was no significant difference in the volumes of chest tube drainage in 6 hours and 24 hours after surgery between the three different TA dose regimen groups. Other measurements also showed no statistical difference between the three groups, included the amount and frequency of allogenic transfusion, and morbidities.Conclusion Lower-dose, moderate-dose and higher-dose TA had the same effects in reducing postoperative chest tube drainage and allogenic transfusion needs in patients undergoing cardiac surgery with cardiopulmonary bypass.