Effect Of Tranexamic Acid On Blood Protection In Patients Undergoing Heart Valve Replacement With Extracorporeal Circulation At Different Regimens

Objective To observe the effect of tranexamic acid（TXA）on hemodilution in patients undergoing cardiopulmonary bypass（CPB）heart valve replacement,and to explore the best application of tranexamic acid.Methods Patients aged 30-70 years who underwent elective heart valve replacement surgery were randomly divided into three groups:control group（group A）:equal dose of0.9%sodium chloride injection;group B:loading dose of tranexamic acid 15 mg·kg^-1given 5minutes after heparinization,followed by maintenance dose of 10 mg·kg^-1-h^-1pumped continuously until the start of CPB;group C:loading dose of tranexamic acid 15 mg·kg-¹given 5 minutes after heparinization,followed by maintenance dose of 10 mg·kg^-1·h^-1pumped continuously until the end of the procedure.The general data,ACT and values of hemoglobin（HB）,red blood cell pressure（HCT）,platelets（PLT）,coagulation function（PT,APTT,FIB,INR）before surgery（T0）,at 8:00 am on the first day of surgery（T1）and at 8:00 am on the second day of surgery（T2）were recorded for the three groups,as well as the allogeneic red blood cell input at T1 and T2,the plasma input and pericardial drainage at T1 and T2.Results A total of 111 patients completed the data collection,general data and ACT among the three groups had no statistical significance（P>0.05）.The ACT after CPB was not statistically significant compared with that before CPB in the three groups（P>0.05）.There was no statistical significance in HB and HCT at each time point among the three groups（P>0.05）,and there was no statistical significance in PLT at T0 and T1（P>0.05）,but at T2,group C was higher than group A（P<0.05）.During intra-group comparison,HB,HCT and PLT of the three groups were lower at T1 and T2 than at T0（P<0.05）,and compared with T1,HB,HCT and PLT at T2 were significantly decreased（P<0.05）.There was no statistical significance in PT,APTT and FIB among the three groups at each time point（P>0.05）,there was no statistical significance in INR among the three groups at T0 and T1（P>0.05）,but INR in group C was lower than that in group A at T2（P<0.05）.During intra-group comparison,APTT:the T1 time point of the three groups was lower than the T0 time point（P<0.05）,the T2 time point of group A and group B was higher than the T1 time point（P<0.05）,INR:the T2 time point of group A was higher than the T0 time point of group A（P<0.05）,FIB:the T2time point of the three groups was higher than the T0 time point of group A（P<0.05）,PT:There was no statistical significance at all time points in the three groups（P>0.05）.There was no significant difference in the amount of allogeneic red blood cells input between groups and within groups at T1 and T2 time points（P>0.05）.Compared with group A at T1,the plasma input in group B and Group C was lower than that in group A（P<0.05）,and the plasma input in group C was significantly lower than that in group B（P<0.05）,but there was no statistical significance among the three groups at T2（P>0.05）.During intra-group comparison,the T2time points in group A and group B were lower than T1 time points（P<0.05）,but there was no statistical significance at each time point in group C（P>0.05）.There was no statistical significance in the number of allogeneic red blood cell input among the three groups（P>0.05）,but the number of plasma input in group C was lower than that in group A and group B at the time points of T1 and T2（P<0.05）.There was no statistical significance in pericardial drainage flow among the three groups at T1（P>0.05）,but compared with group A at T2,pericardial drainage flow in groups B and C was lower than that in group A（P<0.05）,and pericardial drainage flow in group C was significantly lower than that in group B（P<0.05）.In the intra-group comparison,the T2 time point of the three groups was lower than the T1 time point（P<0.05）.Conclusion The blood protective effect of tranexamic acid in cardiopulmonary bypass heart valve replacement surgery is clear and does not affect the intraoperative ACT measurement.After heparinization,the loading dose of tranexamic acid(15mg·kg^-1)and then the maintenance dose of tranexamic acid(10mg·kg^-1·h^-1)were continuously pumped until the end of the operation,which can achieve a better blood protection effect.In CPB,it can protect platelets,promote the recovery of INR in the postoperative coagulation system,and more effectively reduce the postoperative plasma input and pericardial drainage flow,but there is no significant improvement in the postoperative allogenic red blood cell input.