Abstract
Introduction & Aims
Intravenous administration of tranexamic acid (TXA) has been shown to be effective in reducing blood loss and transfusion requirements in total knee arthroplasty (TKA). However, concern exists that I.V. TXA may heighten the risk of venous thrombo-embolism. The intra-articular administration of TXA is an attractive and simple option to deliver this agent locally with minimal systemic effects on inducing hypercoagubale states. In this study, we analysed the effect of varying dosages of intra-articular tranexamic acid on blood loss in TKA.
Methods
176 patients who underwent a unilateral TKA for osteoarthritis were retrospectively analysed. Patients were excluded if they underwent a revision knee arthroplasty, concurrent removal of hardware, extensive synovectomy, or lateral patellar retinacular release. All patients underwent a primary cemented posterior stabilised TKA by 2 surgeons using a medial parapatellar approach. Tourniquet was only inflated for initial exposure and intra-articular drains were not used. Patients were separated into three groups; a control group (n=56) who did not receive TXA, and 2 treatment groups who received intra-articular TXA with doses of 1500 mg (n=60) or 3000 mg (n=60). Once the wound was closed, tranexamic acid was injected intra-articularly via an epidural pain catheter. Haemoglobin (Hb) levels were taken pre-operatively and on post-operative days 1 and 2. The primary outcome measure was mean difference in Hb drop between the three groups.
Results
There was a statistically significant difference in post-operative Hb drops amongst the three groups. Those who received TXA had a greater reduction in the blood loss compared to the control group. In the control group, the mean haemoglobin pre-operatively was 140.13 g/L with an average drop of 34.30 g/L by post-operative day 2. Patients who received 1500 mg of TXA had a mean haemoglobin of 138.95 g/L pre-operatively with an average drop of 28.67 g/L by post operative day 2. Those who received 3000 mg had a pre-operative haemoglobin of 138.02 g/L with an average drop of 22.73 g/L. There were no differences in post-operative complications or local reactions. All inter-group differences in Hb drop on day 2 were statistically significant (p < 0.001, t tests and ANOVA).
Conclusions
There appears to be a dose-dependent effect of intra-articular tranexamic acid on blood loss in TKA, with more efficacy with higher dosages. Intra-articular administration of TXA is an effective and simple way to decrease post-operative blood loss in TKA.
