Summary

The use of 2 g topical intra-articular Tranexamic Acid significantly reduces blood loss and transfusion requirements in primary total knee replacement.

Abstract

The use of Tranexamic Acid (TXA) in cemented primary total knee replacement is supported by studies with a level of evidence of I that confirm its efficacy for decreasing blood loss. Blood loss prevention protocols have been adopted at many institutions, there are concerns regarding intravenous (IV) administration of TXA in some settings, and topical administration may be considered an appealing alternative that is potentially less risky than systemic administration.
Objectives : To assess the efficacy and safety of topical intra-articular application comparing 1 g vs 2 g of TXA , in primary unilateral total knee replacement with cemented implants. The hematocrit drop and blood transfusion rate were the efficacy end points; safety was assessed on the basis of the complications.

Methods

This is a retrospective study of a cohort of patients undergoing unilateral TKA between December 2012 and July 2016. All patients were operated by a single surgeon. The same type of arthroplasty (Vanguard, Biomet Inc., Indiana,Warsaw ) and approach was performed. Exclusion criteria included bilateral surgery, revisions or presence of coagulopathy .
A total of 121 patients were divided into 3 groups:
Group 1 (N = 26), operated between December 2012 and September 2013 TKA without the use of TXA.
Group 2 (N = 40), operated between October 2013 and july 2015 .TXA was used topically (1 g diluted in 20 ml of physiological solution) , and Group 3
(N = 55), operated between October 2015 and july 2016 . TXA was used topically intra articular (2 g diluted in 20 ml of physiological solution) directly on the joint, during the cementation phase, for 5 min.
Preoperative hematocrit and hemoglobin values were compared with the hematocrit and hemoglobin at third post operative day . The need for transfusion of each patient was recorded during hospitalization.
For statistical analysis the program STATA was used. We used chi-square test to compare mean differences between groups.

Results

The mean age of patients was 65 years, SD = 7.4years, with no difference between groups (P = 0.159). There were no differences by gender. The average for all groups preoperative hematocrit was 41%. The postoperative hematocrit average for Group 1 was 30.7%, (SD = 3.5 ) , Group 2 was 31.6% ( SD: 3.34 ) and Group 3 was 33.36% (SD = 3.42). The average decrease in hematocrit for Group 1 was 10.25 points,( SD = 3.13) , Group 2 was 9.45 points (SD:3.4) and for Group 3 was 7.75 points,( SD = 3.32). This results showed statistically significant differences between Group 1,2 vs 3
(p = 0.000111).
Six transfusions were performed in total, 3 of these corresponding to group 1 (6 Unit RBC in total) 2 transfusions for Group 2 (5 Unit RBC in total) and 1 in Group 1 (2 Unit RBC ).

Conclusion

Our results concludes that 2 g topical intra-articular Tranexamic Acid reduces significantly blood loss and transfusion requirements in primary total knee replacements. Patients without the use of TXA have a greater need for transfusion ( average 0.23 vs 0.09 U RBC)