The purpose of this study is to compare a single preoperative dose of 1g of tranexamic acid (TXA) versus a preoperative dose of 1g of TXA followed by a continuous infusion of 1g over height hours on blood loss.

The purpose of this study is to compare a single preoperative dose of 1g of tranexamic acid (TXA) versus a preoperative dose of 1g of TXA followed by a continuous infusion of 1g over eight hours on blood loss. The efficacy of TXA on blood loss is greatly influenced by the timing of its administration relative to surgery. In total hip arthroplasty, TXA should be started before surgery. However the optimal duration of TXA administration in hip arthroplasty is unknown. Numerous studies have shown that a single preoperative administration of TXA is effective. Yet indirect comparisons indicate a higher efficacy of TXA started before surgery and followed with a continuous infusion or repeated boluses. Our hypothesis is that a single preoperative administration of TXA is not sufficient to maintain therapeutic concentrations of TXA in the postoperative period. In addition a pharmacokinetic/pharmacodynamic study will be performed to identify the contribution of TXA plasma concentration as a predictor of blood loss.

Inclusion Criteria:

• Patient requiring hip arthroplasty in first line, except recent hip fracture (less than 3 months)
• Consent of the patient or a family member or the support person.

Exclusion Criteria:

• Contraindication to tranexamic acid.
• Contraindication to apixaban.
• Pregnancy.
• Patient receiving a curative anticoagulating treatment in the preoperative period.