Tranexamic acid and postoperative cell-trans autotransfusion system in patients underwent total Knee replacement – analysis of one year

Background and Goal of Study: Tranexamic acid (TA) and postoperative cell-trans autotransfusion system (CTS) are blood-saving strategies widely used in total knee arthroplasty (TKA). (1)
This study aims to analyse the impact of these two strategies in reducing the haemoglobin (Hb) drop in patients underwent TKA.

Materials and Methods: An observational retrospective study was carried out by analysing the clinical data of all patients who underwent TKA in our hospital during the year 2015. 
Demographic, transfusion and complication data were collected. In our analysis patients were divided in four groups: 1- received CTS; 2 - TA IV was administered before turning up the tourniquet and after lowering it; 3- received both the tecniques; 4- none of the techniques were used. We compared the haemoglobin (Hb) drop in the four groups by analysing the Hb values before and 24h after surgery.
Statistical analysis was performed using SPSSv20.0. The tests used were ANOVA, Chi-square with Monte Carlo correction, Kruskal-Wallis and Bonferroni.

Results and Discussion: Overall, 103 patients were included, 34 males (33%) and 69 females (67%) with an average age of 70,4±6,4 years. There were no significant differences in gender, age, ASA phisical status classification, surgery duration or preoperative Hb, platelet count or INR in the four groups (data not shown). Mean Hb drop (g/dL) in each group is expressed on table 1.

 Table 1	Mean Hb drop (g/dL)
Group 1 – CTS (n= 31)	2,15±0,85
Group 2 – TA (n=51)	2,15±0,77
Group 3 - CTS+TA (n=7)	2,23±0,59
Group 4 - No CTS and no TA (n=14)	2,96 ±1,09

There was a statistically significant difference (p=0,014) in Hb drop between patients who received TA (group 2) or CTS (group 1) and those who did not (group 4). 
When compared to patients who received CTS (group 1) or TA (group 2), patients who received both techniques (group 3) showed no significant difference in Hb drop.
There was no statistically significant difference (p > 0,05) in Hb drop between using CTS (group 1) versus using TA (group 2).
Our series showed an overall complications rate of 17,5% and no thromboembolic events. 

Conclusions: In our population both TA and CTS lowered the Hg drop when compared to the lack of use of those
strategies, but we did not find a statistically significant difference between them.There was no evidence of thrombotic complications with TA during hospitalization.

References: 1- Balaji S, Sahil B, Rajat G, et al. Journ of Clin Orthop and Trauma 4 (2013): 164 – 170.