Tranexamic acid reduces blood loss and financial cost in primary total hip and knee replacement surgery.

Background: Blood conservation strategies have been developed to diminish blood transfusion requirements in patients undergoing hip or knee replacement surgery. Tranexamic acid (TA) is an inexpensive antifibrinolytic agent that is little used in orthopaedic surgery due to the absence of standardised optimal administration regimens.

Hypothesis: Blood transfusion requirements and induced costs can be diminished by using TA according to a standardised administration protocol in a large cohort of patients.

Materials And Methods: A retrospective study in patients who underwent joint replacement surgery by a single surgeon compared two periods, 2007-2008 without TA and 2008-2009 with TA. The 451 included patients underwent primary unilateral hip (n=261) or knee (n=190) replacement for osteoarthritis. Standardised protocols were used for surgery and anaesthesia. TA was given intravenously in a dose of 1g (i.e., 15mg/kg) at incision and wound closure then at 6-hour intervals for 24 hours. Blood losses were estimated using the Mercuriali formula. Haemoglobin on D -1 and D 8 and the number and volume of autologous (from intra-operative blood salvage) and homologous blood transfusions were collected. The costs of TA, blood salvage systems, and homologous blood units were recorded. The two groups were compared using Student's test, Wilcoxon's test, and the Khi(2) test, and multivariate analyses were performed. Values of p less than 0.05 were considered significant.

Results: TA use was associated with a significant decrease in the homologous blood transfusion rate (from 4% to 0%) and with 38% and 68% reductions in the rate and volume of autologous blood transfusions, respectively, due to a 34% decrease in blood losses. After taking into account the additional cost of TA therapy, there was a 25% reduction in the cost of the blood conservation strategy.

Conclusion: TA therapy abolished the need for homologous blood transfusion and induced no notable side effects. TA therapy decreased the amount of blood salvaged intra-operatively, allowing a more rational use of the blood salvage system and decreasing the cost of anaesthesia.

Level Of Evidence: IV. Retrospective case-control.