single versus multi-dose oral tranexamic acid in patients at high risk for blood transfusion after total joint arthroplasty

Conditions: Anemia; Arthritis; Total Knee Arthroplasty; Total Hip Arthroplasty

Summary: as tranexamic acid (txa) becomes more prevalent, all patients are receiving the same dose regardless of their pre-operative risk of transfusion. therefore the aim of the study is to determine whether or not repeated dosing of oral txa reduces the post-operative reduction in hemoglobin, hematocrit, number of transfusions, and post-operative blood loss following primary tka and tha surgeries in patients with low pre-operative hematocrit and high risk for transfusion. the investigators hypothesize that a multi-dose txa regimen will significantly minimize post-operative blood loss and transfusion requirements compared to the use of a single dose regime.

total joint arthroplasty is associated with the risk of moderate to significant blood loss. because txa has been shown to significantly reduce the need for blood products during total joint replacement, it is now the standard of care at many institutions. oral and intravenous txa are equivalent, but oral txa is cheaper and allows for ease of repeat dosing. although low preoperative hemoglobin is a risk factor for transfusion, no studies that have compared standard txa dosing to risk stratified dosing of txa. the investigators hypothesize that a multi-dose txa regimen will significantly minimize post-operative blood loss and transfusion requirements compared to the use of a single dose regimen. at the pre-operative clinic appointment and before the day of surgery, the study staff will assess the potential subject's eligibility. once eligibility is established, the potential subject will be approached regarding their participation in this clinical trial. the investigators will provide 48 hours before the date of surgery to allot for questions and consideration of the informed consent document. once all patient questions have been answered, patients willing to be in the study will sign the informed consent. patients will be randomized, via standard randomization tables that provide a 1:1 distribution of subjects between the two groups through blocked randomization, no later than the morning of surgery to either of the two treatment groups: conventional oral txa group or multi-dose oral txa group.

Eligibility criteria:
inclusion criteria: * older than 18 years * scheduled for a primary cemented tka or cementless tha * preoperative hematocrit less than 36% exclusion criteria: * known allergy to txa * acquired disturbances of color vision * refusal of blood products * pre-operative use of anticoagulant therapy within five days before surgery * a history of arterial or venous thrombotic disease (including a history of deep vein thrombosis, pulmonary embolus, cerebrovascular accident or transient ischemic attack) * pregnancy, breastfeeding * major co-morbidities (myocardial infarction or stent placement within one year, severe pulmonary disease, renal impairment, or hepatic failure) * undergoing a revision tka, revision tha, hip resurfacing, or unicompartmental knee arthroplasty * younger than 18 years old * decline to participate