Tranexamic Acid Dosing in Adult Spinal Deformity Surgery

Low Versus High Dose Tranexamic Acid in Adult Spinal Deformity Surgery: A Randomized, Blinded, Controlled Trial

The purpose of this study is to evaluate two dosing protocols for tranexamic acid (TXA), an anti-fibrinolytic used to decrease blood loss in adult patients undergoing complex, reconstructive spinal fusion surgeries.

After consent is obtained and the patient is enrolled in the trial, patients will be assigned de-identified, unique identification (ID) numbers. Randomization of these IDs to either low or high dose TXA will occur via a computer generated random assignment. Given the variations that may exist in surgical technique (e.g. performance of osteotomies), stratified randomization will be performed by attending surgeon. Based upon the randomization, the pharmacy will prepare TXA for one of two intravenous dosing protocols: Low Dose (Standard of Care/Control): Loading Dose 10mg/kg given over 15 minutes, followed by 1mg/kg/hr via continuous infusion High Dose (Study Group): Loading Dose 50mg/kg given over 15 minutes, followed by 5mg/kg/hr via continuous infusion. The surgeon, anesthesia team, and operating room staff will be blind to the concentration of TXA in the medications received. Treatments may be "unblinded" at the discretion of the surgeon and anesthesiologist, in cases of extreme blood loss. If additional anti-fibrinolytics are given, the change in dose will be recorded. Post-operative care will be the same as any other patient and data collection will be information contained in the patient's medical record that is part of routine, standard of care.

Tranexamic Acid (Cyklokapron) Loading Dose 50mg/kg given over 15 minutes, followed by 5mg/kg/hr via continuous infusion. The loading dose will be given to coincide with incision. The continuous infusion will be stopped at the conclusion of fascial layer closure.

Tranexamic Acid (Cyklokapron) Loading Dose 10mg/kg given over 15 minutes, followed by 1mg/kg/hr via continuous infusion. The loading dose will be given to coincide with incision. The continuous infusion will be stopped at the conclusion of fascial layer closure.

To compare the estimated blood loss in patients undergoing complex, reconstructive, spinal fusion surgeries receiving one of two dosing protocols for the anti-fibrinolytic, TXA. Estimated blood loss was calculated by suction canister volume minus intraoperative irrigation fluid plus blood content in sponges as estimated by weight for all cases.

To compare the mean volume (mL) of packed red blood cell (PRBC) transfusions given to the two groups. Volumes of RBC vary from bag to bag and real volumes will be recorded as provided by the blood bank.

Participants will be followed for the duration of their hospital stay measured from day of surgery to day of discharge from the hospital, approximately 7 days.

To compare the rates of intraoperative complications and 90 day complications observed in the two groups.

Inclusion Criteria: Adult patients (ages 18-75) scheduled to undergo long segment (greater than 8 motion segments) posterior spinal fusion with instrumentation (PSF) for adult scoliosis Exclusion Criteria: Patients with acquired defective color vision Subarachnoid hemorrhage Active intravascular clotting Hypersensitivity to tranexamic acid or any of the ingredients Patients who pre-donate autologous blood for intra- or post-operative use (Directed donor units are acceptable) History of suspected blood disorders or abnormal coagulation laboratory results Current anticoagulation therapy that cannot be interrupted History of deep vein thrombosis (DVT) Impaired renal function or creatinine clearance <60 ml/min Pregnancy or women who are lactating/breastfeeding Women on hormonal contraceptives

Baldus CR, Bridwell KH, Lenke LG, Okubadejo GO. Can we safely reduce blood loss during lumbar pedicle subtraction osteotomy procedures using tranexamic acid or aprotinin? A comparative study with controls. Spine (Phila Pa 1976). 2010 Jan 15;35(2):235-9. doi: 10.1097/BRS.0b013e3181c86cb9.

Neilipovitz DT. Tranexamic acid for major spinal surgery. Eur Spine J. 2004 Oct;13 Suppl 1(Suppl 1):S62-5. doi: 10.1007/s00586-004-0716-2. Epub 2004 May 4.

Okubadejo GO, Bridwell KH, Lenke LG, Buchowski JM, Fang DD, Baldus CR, Nielsen CH, Lee CC. Aprotinin may decrease blood loss in complex adult spinal deformity surgery, but it may also increase the risk of acute renal failure. Spine (Phila Pa 1976). 2007 Sep 15;32(20):2265-71. doi: 10.1097/BRS.0b013e31814ce9b0.

Berenholtz SM, Pham JC, Garrett-Mayer E, Atchison CW, Kostuik JP, Cohen DB, Nundy S, Dorman T, Ness PM, Klag MJ, Pronovost PJ, Kebaish KM. Effect of epsilon aminocaproic acid on red-cell transfusion requirements in major spinal surgery. Spine (Phila Pa 1976). 2009 Sep 1;34(19):2096-103. doi: 10.1097/BRS.0b013e3181b1fab2.

Elwatidy S, Jamjoom Z, Elgamal E, Zakaria A, Turkistani A, El-Dawlatly A. Efficacy and safety of prophylactic large dose of tranexamic acid in spine surgery: a prospective, randomized, double-blind, placebo-controlled study. Spine (Phila Pa 1976). 2008 Nov 15;33(24):2577-80. doi: 10.1097/BRS.0b013e318188b9c5.

Gill JB, Chin Y, Levin A, Feng D. The use of antifibrinolytic agents in spine surgery. A meta-analysis. J Bone Joint Surg Am. 2008 Nov;90(11):2399-407. doi: 10.2106/JBJS.G.01179.

Neilipovitz DT, Murto K, Hall L, Barrowman NJ, Splinter WM. A randomized trial of tranexamic acid to reduce blood transfusion for scoliosis surgery. Anesth Analg. 2001 Jul;93(1):82-7. doi: 10.1097/00000539-200107000-00018.

Sethna NF, Zurakowski D, Brustowicz RM, Bacsik J, Sullivan LJ, Shapiro F. Tranexamic acid reduces intraoperative blood loss in pediatric patients undergoing scoliosis surgery. Anesthesiology. 2005 Apr;102(4):727-32. doi: 10.1097/00000542-200504000-00006.

Shapiro F, Zurakowski D, Sethna NF. Tranexamic acid diminishes intraoperative blood loss and transfusion in spinal fusions for duchenne muscular dystrophy scoliosis. Spine (Phila Pa 1976). 2007 Sep 15;32(20):2278-83. doi: 10.1097/BRS.0b013e31814cf139.

Grant JA, Howard J, Luntley J, Harder J, Aleissa S, Parsons D. Perioperative blood transfusion requirements in pediatric scoliosis surgery: the efficacy of tranexamic acid. J Pediatr Orthop. 2009 Apr-May;29(3):300-4. doi: 10.1097/BPO.0b013e31819a85de.

Goobie SM, Meier PM, Pereira LM, McGowan FX, Prescilla RP, Scharp LA, Rogers GF, Proctor MR, Meara JG, Soriano SG, Zurakowski D, Sethna NF. Efficacy of tranexamic acid in pediatric craniosynostosis surgery: a double-blind, placebo-controlled trial. Anesthesiology. 2011 Apr;114(4):862-71. doi: 10.1097/ALN.0b013e318210fd8f.

Clohisy JCF, Lenke LG, Dafrawy MHE, Wolfe RC, Frazier E, Kelly MP. Randomized, controlled trial of two tranexamic acid dosing protocols in adult spinal deformity surgery. Spine Deform. 2022 Nov;10(6):1399-1406. doi: 10.1007/s43390-022-00539-z. Epub 2022 Jun 25.