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3 echelon surgical hospitals outside the U.S., and Womack Army Medical Center at Ft. Bragg, NC, for U.S. soldiers wounded in Afghanistan and other combat theaters around the world. 12,15,19,23 The Clinical Randomisation of an Anti- fibrinolytic in Significant Haemorrhage (CRASH-2) study, completed by research- ers at the London School of Medicine, and Military Application of Tranexamic Acid in Trauma Emergency Resuscitation study (MATTERs) showed that when TXA can be administered within three hours of injury, the mortality of severely injured patients is reduced by up to 30%. 1–3,6–8,11,13–18,20 With the introduction of TXA to the standard of care and trauma resuscitation protocols of providers in the prehospital setting (for patients who have experienced significant hemorrhage), survival rates should increase further, extrapolating the results garnered in CRASH-2 and MATTERs. We would expect at the least that an increased num- ber of patients would meet the required three-hour treatment window. TXA use in both the CRASH-2 and MATTERs studies showed the greatest reduction in mortality when administration began within an hour of injury. 1–3,6,18 Indications for Prehospital Administration Unlike the chitosan-based HemCon dress - ings (see sidebar), QuikClot Combat Gauze, QuikClot Sponge and CAT tourniquet making their way into civilian prehospital medicine, tranexamic acid is not a hemo- static agent or tourniquet device. 13 TXA is an antifibrinolytic agent that prevents plas- minogen activators from attaching to the lysine binding site of the clot. 1,2,9,14 During fibrinolysis, the process of blood clot breakdown begins when plas- minogen is converted to plasmin, which then begins the destabilization of formed blood clots. 1–3,6,9,14,15 This destabilization leads to increased bleeding and poten- tially patient death (at least in the severely injured trauma patient requiring surgical intervention). 1–3,6,9,14–16 The administration of TXA prevents this clot destabilization cascade from developing. Large prospective randomized, controlled trials have shown that patient mortality is decreased when TXA is administered within three hours of injury. 1,2,6,11,13,14 Mor- tality was shown to decrease even more when it's given within one hour. 1,2,6,11,13,14 With the success of TXA during the clinical trials, its low cost, and its safety and side- effect profile, it is reasonable that TXA be introduced as a standard of care for ALS prehospital emergency medical services in the United States. Any patient who has experienced trauma and is at risk for or has significant hem- orrhage can benefit from TXA. Although transport times in urban settings can be short, TXA may not be beneficial if it greatly delays scene time to prepare and initiate the initial 1-gram dose and establish an IV. However, TXA would be ideal for situations including prolonged extrication, extended transport times due to heavy traffic or other conditions, and mass-casualty incidents. TXA should be administered at the incident site or as soon as an IV has been established, not as the unit pulls up to the trauma cen- ter, to meet the goal of giving the first dose within the first hour of injury. If TXA is administered after three hours, mortality rates have shown to increase. 1–4,15,17 Patients receiving TXA should only be transport- ed to trauma centers that are equipped to handle severely injured patients and can administer or follow patients who have received TXA. Dr. Carl Bergren, a trauma surgeon at St. Francis Trauma Institute of Tulsa, OK, told the Tulsa World TXA has been used on the battlefield as well as on civilians and that using it on patients before they get to the hospital is a good measure. "For those who meet the criteria, it can show a definite benefit," he said. 24 The cost of tranexamic acid versus favorable outcomes in patient mortality is negligible. The current cost of TXA on the British National Formulary converted into international dollars is $5.70 per gram; in the United States the cost is approximate- ly $10 per gram. 4,19 Further, TXA is very easy to administer for paramedics, as they already have training to give intravenous medications in their scope of practice. The recommended procedure for administering TXA is 1 gram in 100 mL of 0.9% normal saline or Ringer's lactate given by IV infu- sion over 10 minutes, followed by 1 gram in 500 mL of 0.9% NS or LR infused over eight hours. 3,4,7–12,14,17 It is recommended that TXA not be mixed with colloid fluid, (e.g., Hex- tend or Hespan, plasma or any other blood components), nor with solutions containing penicillin, and/or piggybacked into any IV line delivering blood. 2–5,9 Review of Current Literature The CRASH-2 study, undertaken in 274 hospitals in 40 countries and published in The HemCon Dressing The HemCon dressing is made from chitosan, a nontoxic complex carbohydrate derivative of chi- tin. It has been in use in the military for several years and when applied directly to the site of arterial hemorrhage and with direct pressure can quickly stop arterial and venous bleeding. 13 EMSWORLD.com | MARCH 2015 25 Any patient who has experienced trauma and is at risk for or has significant hemorrhage can benefit from TXA.