Oral Is as Effective as Intravenous Tranexamic Acid at Reducing Blood Loss in Thoracolumbar Spinal Fusions: A Prospective Randomized Trial.

Abstract

A prospective randomized trial at a university affiliated tertiary medical center between February 2017 and March 2020. The aim of this study was to compare perioperative blood loss in patients undergoing elective posterior thoracolumbar fusion who were treated with IV versus PO TXA. The use of antifibrinolytic agents such as tranexamic acid (TXA) to decrease operative blood loss and allogenic blood transfusions is well documented in the literature. Although evidence supports the use of intravenous (IV) and topical formulations of TXA in spine surgery, the use of oral (PO) TXA has not been studied. A total of 261 patients undergoing thoracolumbar fusion were randomized to receive 1.95 g of PO TXA 2 hours preoperatively or 2 g IV TXA (1 g before incision and 1 g before wound closure) intraoperatively. The sample was further stratified into three categories based on number of levels fused (one-to two-level fusions, three to five, and more than five). The primary outcome was the reduction of hemoglobin. Secondary outcomes included calculated blood loss, drain output, postoperative transfusion, complications, and length of hospital stay. Equivalence analysis was performed with a two one-sided test. One hundred thirty-seven patients received IV and 124 received PO TXA. The average age was 62 ± 13 years (mean ± SD), including 141 females and 120 males. Revision cases comprised of 67% of the total sample. Patient demographic factors were similar between groups except for weight, BMI, and preoperative platelet count. The mean reduction of hemoglobin was similar between IV and PO groups (3.56 vs. 3.28 g/dL, respectively; P = 0.002, equivalence). IV TXA group had a higher transfusion rate compared to PO TXA group (22 patients [19%] vs. 12 patients [10%]; P = 0.03). In addition, IV group had longer length of stay (LOS) than PO group (4.4 vs. 3.7 days; P = 0.02). Patients treated with IV and PO TXA experienced the same perioperative blood loss after small and large spinal fusions. In subgroup analysis, the intermediate (three to five level) spinal fusions had less blood loss with PO TXA than IV TXA. Given its lower cost, PO TXA represents a superior alternative to IV TXA in patients undergoing elective posterior thoracolumbar fusion and may improve health care cost-efficiency in the studied population.Level of Evidence: 1.