The goal of this randomized controlled, double-blinded trial is to assess the efficacy of intravenous tranexamic acid, a drug, in reducing blood loss and transfusion in patients undergoing periacetabular osteotomy, an elective reorientation procedure for the hip joint. The investigators hypothesize that tranexamic acid will be more effective than placebo (normal saline solution) in reducing blood loss and transfusion after periacetabular osteotomy.

Periacetabular osteotomy (PAO) is an elective reorientation surgery for the hip joint, typically for the treatment of hip dysplasia in young, otherwise healthy patients, which requires multiple pelvic osteotomies around the acetabulum. A major source of its perioperative morbidity is blood loss. The principal cause of postoperative blood loss after PAO is surgical trauma, with secondary activation of both the coagulation cascade and local fibrinolysis. In the PAO literature, allogeneic transfusion rates are as high as 58%, and blood loss can range to nearly 4 L. The risk of excessive blood loss and blood transfusion in young, healthy patients after elective surgery is an event that can be reduced with blood conservation protocols, which can include pharmacological agents. Tranexamic acid is a synthetic derivative of the amino acid lysine and a competitive inhibitor of plasminogen activation that interferes with fibrinolysis. Multiple studies and meta-analyses have shown that intravenous administration of the antifibrinolytic agent tranexamic acid reduces postoperative bleeding and the need for transfusion during joint replacement surgery. However, no published data exists to support its use during PAO. We hypothesize that intravenous tranexamic acid will reduce perioperative blood loss and, thus, transfusion requirement in patients undergoing PAO. A total of 80 patients will be enrolled. Patients will be randomized to receive either intravenous tranexamic acid versus placebo (normal saline) during PAO. Calculated total blood loss (primary outcome) will be determined, and intraoperative cell saver utilization (secondary outcome), and (3) postoperative allogeneic blood transfusion (secondary outcome) will be recorded. Patients will be followed for a total of 6 weeks after surgical intervention. If the use of IV tranexamic acid in the PAO patient population significantly reduces total perioperative blood loss, then it would provide an efficacious and inexpensive method for reducing postoperative morbidity after PAO.

Inclusion Criteria:

• Age greater than or equal to 12 years old
• Age less than or equal to 45 years old
• Indicated for elective periacetabular osteotomy

Exclusion Criteria:

• Preoperative use of an anticoagulant (Plavix, warfarin, lovenox, etc.)
• History of hypersensitivity to tranexamic acid
• History of thromboembolic event (e.g., Pulmonary embolism or Deep vein thrombosis)
• History of subarachnoid hemorrhage
• History or evidence of hepatic dysfunction (aspartate transaminase-alanine transaminase ratio greater than 60) or renal dysfunction (Creatinine greater than 1.5 mg/dL, or glomerular filtration rate less than 30 mL/minute)
• History of seizure
• Coronary stents or prior diagnosis of coronary artery disease
• Color blindness
• Leukemia
• Congenital or acquired coagulopathy as evidence by international normalized ratio (INR) greater than 1.4 or partial thromboplastin time (PTT) > 1.4 times normal, or Platelets less than 150,000/mm^3 on preoperative laboratory testing
• Use of hormone replacement therapy or hormonal contraceptive agent within 7 days prior to surgery
• Pregnant
• Breastfeeding
• Donated preoperative autologous blood
• Younger than 12-years-old and older than 45-years-old
• Preoperative hemoglobin less than 10 g/dL
• Concomitant open procedures (e.g., femoral osteotomy or osteochondral allograft)
• Patients with any contraindication to neuraxial anesthesia:
• Patient refusal
• History of lumbar spinal fusion
• Infection at the site of the epidural
• Coagulopathy, as defined above
• Ventriculoperitoneal shunt

Adverse event data was collected through study completion, up to 6 weeks

Only serious venous thromboembolic complications were monitored/assessed.