BACKGROUND…HOW WE GOT HERE
The Tactical Mechanical Tourniquet (TMT) is a CoTCCC recommended tourniquet to be added to the 2019 Guidelines. The TMT is one of the newest tourniquets to be proposed to the Department of Defense since 2005. Current tourniquets are over 14 years old, and a generational change has been long overdue. While tourniquet implementation led to a reduction in the number of deaths from extremity hemorrhage, there is still a myriad of limitations that need to be addressed.
Read more about how the DoD Tourniquet Working Groups established a standard tourniquet requirements document.Read more
The following are the pertinent requirements generated by the various DOD Tourniquet Working Groups:
- Must occlude arterial blood flow to upper and lower extremities
- Minimum width must be 1.5″
- Weight must not exceed 8 oz
- Color must be subdued
- Device must be compact; cube must not exceed 6.5″ x 1.75″ x 2.25”
- Device must have a protective casing; this enclosure must be sealed or shrink-wrapped
- Device must be easy to open in an operational environment
- Latex-free components
- Minimum length must meet or exceed 37.5”
- Product must be registered appropriately with the FDA
The following characteristics are desired, but are not required in the case of pre-hospital/field tourniquets:
- Capable of self-application
- Possess tracking information; quality assurance or date of manufacture present on device
- Device will not break or deform with applied pressure of 0-500 mmHg
- Use in arctic, desert, tropical, and temperate environments without affecting performance
- Use with UV exposure will not affect performance
- Capable of being used while wearing full kit gear, in low light and no light
- Use with gloves: flight gloves, MOPP gloves, shooting gloves, and cold weather gloves without affecting performance
- Single patient use; capable of repositioning from over clothing to skin on same patient
- Instructions for use will be inside the package or will appear on the device in a written or pictorial format
- User will be able to correctly apply the device following instructions included in packaging
- Stitching and other connective methods will be sufficient for pressures exerted on materials according to device requirements
 Eastridge BJ., et al., Death on the battlefield (2001-2011): Implications for the future of combat casualty care. J Trauma Acute Care Surg. 2012 Dec;73(6 Suppl 5):S431-7.
DESIGN… WIDER & EASIER MAKE FOR A BETTER TOURNIQUET
WIDER IS BETTER
The TMT is a major advancement in tourniquet care with its 2″ wide pressure band, and it resolves issues that make a profound difference in the amount of blood loss from extremity hemorrhage. Older tourniquet designs are documented as being too narrow to guarantee successful occlusion with one tourniquet.
The TCCC Guidelines as of August 2018 and the Soldiers Manual of Common Tasks, are just a few of the sources that have recommended or reported that a second CAT should be applied when bleeding cannot be controlled using just one. To be clear, it is important to reassess every medical intervention for proper efficacy; however, Combat Medical does not believe anyone should routinely need two tourniquets to stop the bleeding of one extremity. Studies have proven a single TMT effectively halts blood flow at a low circumferential pressure due to its two-inch-wide band.
Read more about how the TMT’s design eliminates unnecessary steps and unsafe design flaws inherent in other tourniquets.Read more
The TMT’s wider band successfully halts blood flow at a much lower pressure of approximately 296 mmHg, thus requiring less mechanical force and less stress on the hardware, reducing the chance of failure. Narrower designs create high pressure of up to 500 mmHg which can cause neurological damage and often lead to device failures.
EASIER IS BETTER
The key issue to overcome was eliminating the number of things you “must remember” and “can’t forget” in order to get an older tourniquet design to work properly. Trainers often put these tourniquet shortcomings and failures on the end-user as if it was somehow the user’s fault. This creates “training scars” that debilitate the confidence of the person being trained.
The TMT’s key design features allow you to ELIMINATE the following steps:
- “Pre-loading”: No unnecessary steps in order to prepare your tourniquet for use. The TMT eliminates the need to “pre-load” the windlass retainer, or the need to trace the tail prior to use.
- Two step securement: The patented TMT windlass clip securely locks the windlass in one fluid motion with a confirmatory click. This feature eliminates two steps to secure older tourniquets.
- “Thread your tail”: The TMT’s speed-buckle allows for easy application on leg applications, entrapped limbs or during confined space scenarios.
- Critical slack: The TMT’s buckle secures and holds the strap as you tighten. This eliminates the need to simultaneously pull tension and align the Velcro around the extremity.
- Strap inversion: The TMT never needs to be unthreaded from the buckle, so it cannot be misrouted or inverted- which can lead to “nylon-to-Velcro failure” in older designs. This is a huge advantage of the TMT during limited visibility or confined space situations.
- Reliance on Velcro®: The TMT does not rely on Velcro to maintain hemorrhage control. The TMT is securely held by the tension buckle alone. No lifesaving piece of equipment should ever rely on Velcro as its sole securing mechanism. The TMT tail does not need to be taped down to secure the device.
- Protected from the elements: The TMT is built from one of the highest durability polymers available, which contributes to its indefinite stored shelf-life (operational storage of 10 years). This ensures operational reliability in environmental extremes ranging from -20°F to 140°F. Additionally, both the hardware and straps are treated with UV/IR protective additives to defend the TMT from UV/IR exposure and subsequent degradation. This eliminates the need to replace your tourniquet during a deployment cycle due to UV exposure.
Committee on Combat Casualty Care, TCCC Guidelines for Medical Personnel. 2018 Aug;2
Soldiers Manual of Common Tasks (SMCT)(STP-21-1- SMCT). (2017). Washington, D.C.: Dept. of the Army, Headquarters.
Beaven, Alastair and Rob Briard, et al. “Two New Effective Tourniquets for Potential Use in the Military Environment: A Serving Soldier Study.” Military Medicine (July/Aug 2017): e1929
 Naval Medical Research Unit San Antonio, NAMRU-SA REPORT#2015-52
Ochoa J, Danta G, Fowler TJ, Gilliatt RW. Nature of the nerve lesion caused by a pneumatic tourniquet. Nature. 1971 Sept;233:265-6.
Piper L. Wall, DVM, PhD et al, Tourniquets and Occlusion: The Pressure of Design, Military Medicine, 178, 5:578, 2013
RESEARCH… REFINING THE SOLUTION
The Combat Application Tourniquet Versus the Tactical Mechanical Tourniquet; Beaven et al. 2018
“American and British military doctrine advocates the use of two C-A-Ts side by side if bleeding is uncontrolled with one tourniquet. In fact, a real-world study reported the percentage failure of singly applied C-A-T to be 18%, with the thigh being the least successful body region.” “An improvement to the currently used C-A-T would be a device that consistently controlled hemorrhage when used at the mid-thigh level without the need for a paired application. We tested two such devices that we believe can control lower limb hemorrhage when applied singly to the mid-thigh.” “The time to reach complete arterial occlusion was a median of 37.5 (IQR, 27–52) seconds with the C-A-T, and 35 (IQR, 29–42) seconds with the TMT. The 2.5-second difference in median times was not significant (p = .589). The 1-in-10 difference in median pain score also was not significant (p = .656).” “All the study participants had self-applied the C-A-T before during training, and some had applied the C-A-T to other wounded Soldiers, but none had used the TMT before.”
Two New Effective Tourniquets for Potential Use in the Military Environment: A Serving Soldier Study; Beaven et al. 2017
“Despite its undeniable successes, the combat applied tourniquet (C-A-T) has some shortfalls, principally its inability to reliably control lower limb bleeding when applied to the mid-thigh.” “Both the tactical mechanical tourniquet and the tactical pneumatic tourniquet demonstrated ability to completely occlude the popliteal artery in 100% of limbs when applied at the mid-thigh level in healthy volunteers. All participants reported acceptable pain scores with both tourniquets. These devices require further investigation to assess their battlefield utility, once this is done, current tourniquet guidelines should be urgently reviewed.”Read more
Preliminary Comparison of New and Established Tactical Tourniquets in a Manikin Hemorrhage Model; Gibson et al. 2016
“It is evident, however, that a second tourniquet, the TMT, did perform as well as the C-A-T, and required a lower mean pressure to stop hemorrhage. Hence, subject to the relative cost of each, the TMT might prove to be a successful competitor on the open market.”
Test and Evaluation of New York City Industries for the Blind (NYCIB) Tourniquets- NAMRU Phase 1; Dory et al:2014
“All tourniquets met the criteria for length, width, weight, and physical characteristics were consistent within each tourniquet type.” “Each tourniquet demonstrated the ability to achieve the necessary occlusion pressure, and similar applications times were observed for each type.” “the average application time on the arm was 33.3 +/- 6.3 seconds, TMT achieved and maintained 100% occlusion.”
Evaluation of Extremity Tourniquets in the Hands of Non-Medical Personnel in Simulated Field Conditions NAMRU Phase 2; Dory et al: 2015
“In this evaluation of extremity tourniquets, conducted in the hands of non-medical volunteer participants, both TMT and TPT tourniquets effectively halted blood flow on the HapMed mannequin leg and arm, in each of the simulated field conditions. By using standardized methods and test instruments established in earlier tourniquet evaluations (Alvarez, 2014), the overall success and performance of the TMT and TPT tourniquets, can be compared not only against each other, but relative to previously tested tourniquets. The performance metrics obtained here also function as benchmarks for emerging tourniquet designs. This data serves to inform the tourniquet selection process and ensures the US warfighter is equipped with the most effective and operationally sound tourniquet systems.” “Those consensus requirements were implemented in two initial phases of testing, the Joint Operational Evaluation of Field Tourniquets (JOEFT) Phases I and Phase II (McKeague, 2012; Alvarez, 2014), which evaluated eleven tourniquet designs that were FDA registered.” “All ten participants applied both the TPT and TMT successfully to the HapMed leg, generating occlusion within five minutes, and maintaining occlusion during the one-minute monitoring period, in each of the four test conditions.”
VALIDATION… CONFIRMING THE RESULTS
The TMT completed the most comprehensive initial field evaluation of any tourniquet to date. After successfully completing Phase I through Phase IIIB evaluation by Navy Medical Research Unit San Antonio, 140,000 TMT’s were fielded within US Military Units deployed around the world. This initial fielding is part of our Low Rate Initial Production (LRIP) process.
During a DoD product development, LRIP is the key element of the Joint Capabilities Integration and Development System (JCIDS) process. Our team at Combat Medical understands this and embraces the extensive fielding and feedback which is critical to ensure comprehensive LRIP review and validate results. The LRIP feedback resulted in two minor production adjustments: the speed buckle was enhanced to make pulling slack smoother, and bolstering of the windlass retention clip.
USER EVALUATIONS: As a culmination of the LRIP process, Combat Medical conducted over 800 end-user surveys following MARCH training to validate its effective design. These user evaluations documented a 80.9% positive feedback regarding the TMT’s abilities compared to their issued tourniquet. This aided in the creation of superior technology that effectively supports the US warfighter in the field.
Read more about the TMT’s abilities in the field and some of the case studies we have gathered to date.Read more
EXAMPLES OF TMT LIVE FIELD USES:
With nearly 100 live-uses, the TMT has proven its capabilities in a variety of environments and conditions. These experiences validate the TMT’s research, design, and overall efficiencies that set it apart from other tourniquets.
Law Enforcement Case Study:
A hostage situation occurred on May 15, 2018, in Mount Holly, NC. A Police Officer used his department issued TMT on a subject that had been shot in the upper leg and was bleeding. The TMT was applied in less than 30 seconds and halted blood flow with only two turns of the windlass torsion bar. The subject was taken to a local hospital by EMS and survived his injuries. The Mount Holly officers had been trained only a week prior to the incident.
Remote Care Case Study:
The TMT’s resilience and robustness are clear after the feedback received from Shinyanga Regional Referral Hospital in Tanzania regarding two donated TMT tourniquets. From May 2016 to August 2018 the TMTs were applied mid-thigh on patients requiring amputations from chronic illnesses. Over the course of 2 years, because of the remote location, the same two TMTs were reused multiple times, after being scrubbed, soaked in bleach and left to dry in the sun. The TMTs were 100% effective in stopping blood flow and reported zero failures and zero slippage.
Civilian Casualty Case Study:
Late February 2019, during inclement weather, a truck hit a guardrail, suffering heavy damage to the front of the vehicle. This provider happened to witness the accident and stopped to assist. Upon opening the door, he noted that the driver had an open fracture of her right ankle with both bones protruding from the injury. There was a steady stream of blood and her all-weather mats had collected a significant amount of blood. He treated the driver by applying a TMT from his IFAK and without difficulty, stopped the bleeding. From there, they were able to transfer the patient to an ambulance.