Efficacy and Safety of Tranexamic Acid in Spinal Fusion Surgery

The purpose of this study is to see if Tranexamic Acid can safely reduce bleeding in people undergoing spinal fusion surgery.

This will be a multicenter, randomized, double-blind, parallel group study comparing tranexamic acid (test) to placebo (control) for reduction of perioperative blood loss after complex spinal fusion surgery (defined as T2 to Pelvis/Sacrum and greater than 4 Functional Spinal Units (4 discs/motion segments=5 Vertebral segments)). In addition to test and control treatments, all patients undergoing spinal fusion surgery will receive anesthesia and standard of care for blood loss including colloid/crystalloid fluid replacement and packed red cells, if necessary, according to a common multi-institutional protocol. Anesthesia will keep the mean arterial pressure as low as safe for the patient during exposure of surgery (estimated at 60-80 MAP). Patients will be randomized to receive either 30 mg/kg tranexamic acid as a one hour infusion (3 mL/kg) loading dose prior to start of procedure and as an infusion at 3 mg/kg/h (0.3 mL/kg/h) of tranexamic acid throughout the surgery in the test group; or, a one hour infusion at 3 mL/kg of 0.9% saline prior to start of the procedure and an infusion of 0.9% saline at 0.3 mL/kg/h in the control group. The maximum total dose will be 50 mg/kg.

The active phase of the study will be until discharge postoperatively for efficacy measurements and at 6 weeks for safety follow-up. The randomization will be open only to the statistician generating the randomization sequence. All PI(s), study conduct and monitoring staff, as well as the subjects will be completely blinded to the treatments except in the case of emergency.

The study will be terminated if ≥5/12 or 10/36 patients enrolled in the study are diagnosed with treatment related serious adverse events.

Eligibility Criteria:
Inclusion Criteria:

* All adult patients (Male or Female) over age eighteen (\>18) electively undergoing complex spinal fusion surgery (defined as T2 to Pelvis/Sacrum and greater than 4 Functional Spinal Units (4 discs/motion segments=5 Vertebral segments).
* Female subjects of childbearing potential with a negative serum (beta human chorionic gonadotropin \[HCG\]) pregnancy test at screening and urine pregnancy test at each admission; who are not breastfeeding; do not plan to become pregnant during the course of the study; and agree to use an approved method of birth control, such as condoms, foams, jellies, diaphragm, intrauterine device, sexual abstinence for at least 3 months prior to study
* Able to provide written informed consent after risks and benefits of the study have been explained
* Able to communicate effectively with study personnel.

Exclusion Criteria:

* History or presence of any clinically significant (based on the Investigator's judgment) cardiovascular, respiratory, metabolic, hepatic, gastrointestinal, renal, hematological, dermatological, neurological, or psychiatric disease or condition preventing the use of tranexamic acid
* History of renal failure or elevated creatinine above 1.4
* Any diagnosis of spinal tumor or intradural pathology
* Diagnosis of ankylosing spondylitis
* History or presence of acquired disturbance of color vision
* History of seizures
* History of thromboembolic event (DVT or PE) within the past year
* Current use of anticoagulant medications or past medical history leading to an abnormal coagulation profile preoperatively
* Subjects diagnosed with fibrinolytic disorders requiring intra-operative antifibrinolytic treatment; hematological disease (thromboembolic events, hemoglobinopathy, coagulopathy, or hemolytic disease)
* Significant drug sensitivity or significant allergic reaction to any drug, including tranexamic acid, based on the Investigator's judgment
* A subject who has donated or lost 450 mL or more blood volume (including plasmaphoresis) or had a transfusion of any product within 3 months prior to the initial study drug administration
* Pre-operative anemia (hb \<110 in females, Hb \<120 in males)
* Any subject that chooses to refuse blood products for ethical or religious purposes (Jehovah's Witness)
* Current participation in a drug or other investigational research study or participation within 30 days prior to the initial study drug administration
* A subject who may not be able to comply with the safety monitoring requirements of this clinical trial or is considered by the investigator, for any reason, to be an unsuitable candidate for the study.
* Intraoperative cardiovascular, pulmonary, orthopedic, or anesthetic complication such as myocardial infarction, intraoperative fracture, vasopressor support or emergent intubation.
* Female patients who are using combination hormonal contraception.
* Patients with history of subarachnoid hemorrhage.
* Patients with serum creatinine above upper limit of normal (ULN).