This study evaluates the efficacy of tranexamic acid versus placebo on perioperative blood loss using two dosage regimens (standard and extended) after a surgery during total hip arthroplasty in patients receiving the novel fast-acting oral anticoagulant rivaroxaban for prophylaxis of thrombosis.

In 2011, 140 000 total hip replacements were performed and bleeding remains one of the major complications responsible for significant morbidity. This study will evaluate a new treatment to prevent bleeding due to this surgery. Indeed, the tranexamic acid (Exacyl) will be used in two modes of administration (standard or extended) versus placebo combined with a Rivaroxaban treatment at a dose of 10 mg / day for 35 days.

Patients will be randomized (exacyl standard vs exacyl extended vs. placebo) and will be followed for 3 months.

Inclusion Criteria:

• Over 18 years of age
• Scheduled to undergo elective non-traumatic primary cementless THA
• Having given written informed consent to participate in the trial
• Covered by Social Security

Exclusion Criteria:

• Rapidly destructive arthrosis of the hip

• History of prior surgery on the operative hip

• Contraindications to the use of tranexamic acid:

  • Ischaemic artery disease (angina pectoris, myocardial infarction, acute coronary syndrome or stroke)
  • History of venous thromboembolism
  • Severe renal impairment, i.e. with clearance < 30mL/mn
  • Epilepsy or history of convulsions

• Contraindications to the use of rivaroxaban

  • Severe renal failure (clearance <30ml / min)
  • Cirrhotic patients with Child Pugh B
  • Pregnancy and breastfeeding

• Cognitive disorder that precludes giving informed consent

• Refusal to participate in trial

• Allergy to either of the trial treatments

• On-going prophylaxis of thrombosis using an agent other than rivaroxaban

• On-going platelet aggregation inhibitor at a dose exceeding 125 mg daily