This study compares two oral medications (tranexamic acid and aminocaproic acid) as hemostatic agent administered in patients undergoing primary total hip replacement

With the aging population, the incidence of joint osteoarthritis is rising. Total hip arthroplasty (THA) is one of the most common surgeries used for the treatment of end-stage degenerative hip disease, which is almost always accompanied by joint pain, deformity and motor dysfunction.

Few articles have compared TXA and ε-ACA in joint arthroplasties. Whether ε-ACA has comparable hemostatic effects compared with TXA is unknown. A recent systematic review compared the effectiveness of TXA versus ε-ACA administered intravenously as a hemostatic agent in patients who had undergone a TKA and THR, and the results showed that the total blood loss was greater in the ε-ACA groups, but no significant differences between the two groups regarding transfusion rates were identified (Liu et al., 2018).

Regarding oral administration, two clinical trials compared the use of oral TXA versus intravenous and topical in patients who had undergone THA, reaching the conclusion that if efficiency, safety, and cost are considered the main crucial parameters during the evaluation of TXA administration methods, oral TXA stands as an efficacious, safe, and low-cost method to reduce blood loss after THA compared with the IV and topical forms. Additionally, considering the ease of drug administration in the tablet form, oral TXA appears to represent a superior mode of administration than IV and topical TXA (Kayupov et al., 2017; Luo et al., 2018).

The investigator's work team previously published a randomized controlled clinical trial in which it prospectively compared blood loss, transfusion rate and complications similar to this study but in total primary knee replacement, finding no differences with respect to any of the parameters studied except for the adverse effects, which were greater for the group that received tranexamic acid, this study was the first to compare the oral administration of these two medications in the field of orthopedics (Morales-Avalos et al., 2019) and the present protocol wants to do it now in the total primary hip replacement which is well known to be associated with greater blood loss than total knee replacement.

HYPOTHESIS: There are no significant differences in blood loss (total blood loss, external blood loss, hidden blood loss, intraoperative blood loss and drainage output), transfusion index, complications and hemoglobin/hematocrit levels in patients undergoing total hip prostheses treated with tranexamic acid or aminocaproic acid orally.

General objectives To compare the effect of oral aminocaproic acid as a hemostatic agent against oral tranexamic acid administered preoperatively and postoperatively in patients undergoing elective surgery of total hip replacement.

Specific objectives

1. Selection and randomization of patients.
2. Performing total hip replacement surgery and administration of AAC or AXA according to randomization and the methodology established in this protocol
3. Establishment of a protocol for the administration of aminocaproic acid orally for its use as a hemostatic agent in elective surgery of total hip replacement.
4. Determination of total blood loss, external blood loss, hidden blood loss, transfusion index, decrease in hemoglobin/hematocrit levels, drainage volume, intrahospital stay, analogous visual scale and SF-12 scale between tranexamic acid and the aminocaproic acid, both orally, in each group in the pre-operatively, trans operatively and post-operatively established times and compare them statistically.
5. Determine and record the possible complications and side effects observed with the use of both drugs included in the study.
6. Determine the cost and monetary savings associated with the administration of each drug.
7. Comparison and statistical analysis of the results between the study groups.

Inclusion Criteria:

1. Age over 18 years
2. Total replacement of the primary hip due to: 1) Primary Coxarthrosis, 2) Avascular hip necrosis, 3) Transcervical fracture
3. Unilateral procedure
4. Press-fit prosthesis
5. Without the use of cement for the placement of the prosthesis
6. Desire to participate voluntarily in the study and signature of informed consent
7. Pre-operative assessment with result between ASA I, ASA II or ASA III performed and annexed in the clinical file either by the Department of Internal Medicine, Cardiology or Anesthesiology of our hospital.
8. Possibility for oral administration of the drug.

Exclusion Criteria:

1. History of thrombotic or embolic event in the last 6 months
2. Clinical history of coagulopathy
3. Previous surgeries in the hip to intervene
4. Patients who have received aspirin, platelet or coumarinic antiplatelet agents in the week prior to surgery or NSAIDs two days prior to surgery.
5. History of myocardial infarction, arteriopathy or unstable angina in the 12 months prior to surgery.
6. Those patients whose preoperative assessment corresponds to an ASA IV or the procedure is contraindicated in its preoperative assessment.
7. Revision hip replacement
8. Tumoral hip replacement
9. Bilateral hip replacement
10. Cognitive deficit
11. Patients who meet the inclusion criteria but do not wish to participate in the study
12. Patients with a diagnosis of Terminal Chronic Kidney Disease or with a serum creatinine higher than 1.47 mg / dl in the preoperative laboratories.
13. Patients with inability to ingest the drug orally.
14. Patients who are pregnant or breast-feeding or who are taking oral contraceptives.
15. Seizure history
16. Hypersensitivity to the active substance or to any of the excipients

Prior to being included in the study, the patient will be mentioned the times when he will receive the medication as well as the dosage of administration. The patient will not know what medication is being administered to him / her. The pills will be given to the patient in a medicine cup without access to any information legend. In the same way, the medication will be administered by a doctor outside the research protocol and will not participate in any other phase of the study so that no member of the research team will know what medication was administered.