Summary

Althought the patiens in the tranexamic acid presented an average of 140 ml less blood loss tha the patiens in the e-ACA group the difference does not appear to be clinically important, the transfusions rate was very low, and there were no between-group differences in postoperative complications

Abstract

Introduction. Total primary knee replacement result in significant post-operative bleeding. There are reports that 20 to 50% of the patients require blood transfution wich has been related to many complications resulting in the reaserch of strategies to reduce the bleeding. The use of oral antifibrinolytics is becoming a low cost and safe way to this end, revealing stadistic and clinical results similar to the topical and intravenous presentation and there is no previous study comparing two of the most commonly hemostatic oral antifibrinolytics used in total primary knee replacement

Methods. In this randomized, controlled trial, we enrolled 92 patiens that underwent total knee replacement surgery as a result of primary knee arthrosis. Patiens where randomly divided in two groups to take 3 dose of aminocaproic acid (1000 mg per dosis) in the day of the surgery or 3 dose of oral tranexamic acid (1300 mg per dosis) in the day of the surgery. The drugs where administrared in the following schedule: 2 hours before the surgery and, post-operative 6 and 12 hours after the surgery. The variables analyzed in order to compare the effectiveness as homeostatic agents were total blood lost, hidden loss blood, external loss blood, transfusion rate, intra-operative blood loss, a decrease in hemoglobin and hematocrit values at 24, 48 and 72 hours, surgical drainage output, functional scales (SF-12), Visual Analogue Scale (VAS) and complications of the surgery. All of the variables were analyze using stadistical methods.

Results. There are no significant differences between any of the study variables withing the group receiving oral aminocaproic acid vs. oral tranexamic acid (p >0.05), with the exception of the patients reciving tranexamic acid presenting less advers events (p= 0.04). In spite of the evidence of less blood loss with the use of oral tranexamic acid the results where not stadistically significant.

Conclusions. Our study showed that the use of oral aminocaproic acid is similar to his counterpart the tranexamic acid regarding the evaluated parameters. Althought the patiens in the tranexamic acid presented an average of 140 ml less blood loss tha the patiens in the e-ACA group the difference does not appear to be clinically important, the transfusions rate was very low, and there were no between-group differences in postoperative complications