Optimal Route for Tranexamic Acid in Diabetics and Obese Patients Undergoing Primary Total Knee Arthroplasty - a Data from Randomized Study.

PURPOSE OF THE STUDY To determine the optimal strategy for tranexamic acid (TXA) administration in diabetic patients, smokers and obese patients (BMI > 30 kg/m2) undergoing primary total knee arthroplasty (TKA). MATERIAL AND METHODS The total of 400 consecutive patients indicated for primary TKA were randomised into 4 basic groups with different TXA administration regimens. Group 1 (IV1) had a single intravenous dose (15 mg TXA/kg) applied prior to skin incision. Group 2 (IV2) got two intravenous doses (15 mg TXA/kg): one prior to skin incision and one subsequently 6 hours after the first dose. Group 3 (TOP) had 2 g TXA in 50 ml of saline irrigated topically at the end of the surgery. Group 4 (COMB) combined IV1 and TOP regimens. We monitored the amount of total blood loss (TBL), haemoglobin drop, use of blood transfusions (BTs), and complications in each patient. Follow-up period was one year postoperatively. RESULTS In the group of diabetic patients (n = 87; 21.7%) the lowest TBL was observed in the order: IV1, IV2 > COMB > TOP. In the obese patients (BMI > 30 kg/m2; n = 242; 60.5%), TBL was significantly lower in the intravenous regimens (IV1: p = 0.002; IV2: p = 0.005, respectively) than in the TOP regimen. In the smoking patients (n = 30; 7.5%), TBLs were significantly lower in the order: IV1 > IV2 > COMB > TOP. DISCUSSION Individualised approach to prevention and therapy is a recent trend, also because comorbidities significantly affect the result of the intervention. In the case of diabetes, obesity and smoking, there is a proven link to early post-operative infections, mainly due to poorer innate immunity. It is conceivable, though, that the occurrence of infectious complications is also contributed to by larger hematomas or hemarthroses which are largely preventable. CONCLUSIONS In the diabetic and obese patients (BMI > 30 kg/m2), the combined topical/intravenous TXA application and two intravenous doses of TXA interventions were shown to be the most effective. However, no evidence of superiority of any of the TXA administration routes was obtained in the smokers. None of the TXA protocols was associated with a higher incidence of complications or early reoperation following TKA surgery. Key words: tranexamic acid, topical application, intravenous application, combined administration, diabetes, obesity, BMI, smoking, blood loss, hidden blood loss, total knee arthroplasty, complications.