Tourniquets: Which to Use and Why

Tourniquets have been used as far back as ancient Greece to stop blood loss from traumatic wounds. They have always consisted of bands that were tightened to stop blood flow. In fact, a tourniquet can be made out of many common items. However, when someone is bleeding out from a traumatic wound, constructing a rudimentary tourniquet may be unsafe & ineffective. If you’re going to be in a high-risk scenario, you should be equipped with a professionally manufactured tourniquet tested for efficiency & safety.

Despite the widespread idea that tourniquets are only to be used as a last-resort, they have been used safely & effectively. In fact, physicians & medics with combat experience reported that liberal use of a tourniquet saved many lives when the tourniquet had been applied appropriately & properly. Uncontrolled hemorrhage continues to be the leading preventable cause of mortality death. This is true for both civilian and current military environments, since devastating accidents happen, and criminals may carry combat weapons can cause significant trauma to extremities. Add to this the fact that several tourniquets have been tested & demonstrated their effectiveness while inflicting little to no harm. Civilian applications like EMS are therefore certainly appropriate.

On the battlefield, where combat weapons can inflict horrible wounds, tourniquets are a key component to any field medic & soldier’s gear. It is therefore unsurprising that the military has focused much of its medical research on development of hemorrhage control, including tourniquets. Modern advances such as wider straps & mechanical tightening mechanisms have greatly increased the efficiency & safety of tourniquets.

Below is a comparison of several popular tourniquets:

> Combat Application Tourniquet (CAT)

The CAT is one of the first manufactured tourniquets, one of the most common used by the military & our most popular. It secures with velcro & uses a windlass to twist the strap tighter. The windlass is secured by inserted one end into a cradle.

From the manufacturer’s description:

• The official tourniquet of the U.S. Army
• Proven to be 100% effective in occluding blood flow in both upper & lower extremities by the U.S. Army’s Institute of Surgical Research
• Hailed as being one of the fastest tourniquets to employ

The CAT Tourniquet features two different methods of employment: single hand and dual hand. The strap needs to be threaded through the plastic buckle differently depending on whether it’s being used on an upper or lower extremity. The application time is under 30 seconds for one-handed application to the arm and a little over 10 seconds when applied to the leg. Two-handed application can take over a minute & may prove a little frustrating. You can always train to become very proficient in the various methods, but perhaps a single, consistent system would be ideal.

> SOF Tactical Tourniquet

The strap of the SOF Tactical Tourniquet is secured with a quick-connect / break-apart buckle and tightened with a windlass like the CAT. The windlass is secured by a “tri-ring” or D-ring at one end.

Two versions are available: The original SOF-T with a 1″ wide strap & the newer SOF-T Wide with a 1.5″ strap

From the manufacturer’s description:

• One of the top performing tourniquets currently available
• Proven to be 100% effective during US Army Institute of Surgical Research testing
• The result of an exhaustive 24-month research initiative compiling end-user research and laboratory studies to develop a more effective, easier-to-use tourniquet for all environments. High-strength, light-weight alloy components are used in critical areas of function ensuring reliability in the most challenging of circumstances and on the largest of limbs. This was all accomplished while reducing the weight by an amazing 25%.

The SOF Tourniquet features a high level of reliability and is easy to apply. It has been tested and is used by the military, & has proven to be extremely effective in high stress situations. More lightweight than ever, it is easy to carry.

One of the complaints on the older, thinner SOF-T is the tension thumbscrew that is supposed to keep the tourniquet from loosening once it is tightened down. If you set it up too tight it will bind the strap keeping you from removing slack. The newer wide model does not have this thumb screw and instead has a traditional slip gate type buckle.

Important to note is that the SOF Tourniquet is popular with combat re-enactors. This has led to a number of units that are merely props and do not work to stop blood flow. It is difficult to tell the difference, so make sure you are buying them from a medical retailer.

> MATResponder Tourniquet (Formerly MAT Tourniquet)

The MATResponder is constructed with a rigid C shaped plastic Collar & constricting strap. The strap is secured around the limb with a buckle hook. A turning handle tightens the tourniquet.

From the manufacturer’s description:

• Developed for first responders and based on an award-winning design originally developed for the US Department of Defense— MATResponder can be quickly applied in the field to all limbs (with one hand, if necessary), and features a mechanical system to provide safe compression in controlled increments.
• Awards for MAT include the IDSA’s Gold Award for Best Medical Product Design of 2006, Design of the Decade in 2010 (Silver), and 2007 INDEX Award for best medical product in the world (Finalist).
• 100% blood flow occlusion in 30 seconds
• Can be applied in small, controlled increments and easily released.
• One hand application.
• Easy to use and learn for all levels of medical and non-medical personnel.
• Multi-purpose application to arms, legs and trapped limbs.
• Secure.Mechanical advantage tourniquet system ensures that MATResponder does not slip or loosen.
• Light weight, compact design.
• Durable. Operates in extreme conditions, such as mud, water and sand submersion, extreme cold, ice-encrustment and hard surface (concrete) impact.

The strap has a limited ability to tighten, so the tourniquet strap must be tightly applied. It is more bulky & therefore harder to pack than other tourniquets. However, the tourniquet is easily released by either lifting the plastic hook that locks down the strap, or by pressing the release button

Some studies ranked it highest in:

• Speed of application
• Median average application time
• Dominant vs. non-dominant hand application time
• Mean average application times for upper and lower extremities
• Occlusion efficacy/efficiency
• User preference

> Junctional Tourniquets

IED's have been a leading cause of death for military servicemen & women throughout both Iraq & Afghanistan. This was mostly since the resulting pelvic and upper leg injuries could not be easily treated with conventional tourniquets. So a former combat medic developed one that did: The junctional tourniquet. These are purpose-built to treat pelvic and upper leg injuries that can result from an IED attack.

The SAM Junctional Tourniquet was rated one of JEMS Hot Product from EMS Today in 2014.  This tourniquet weighs a little over a pound and can be applied in just under 25 seconds, though some report the application taking over 70.

Four different commercially available devices were evaluated by the military on their ability to stop blood flow distal to the application site. These medics rated the SAM Junctional Tourniquet device among the easiest and fastest to apply. It was the second cheapest from those evaluated&  the only device to reach 100% effectiveness in stopping blood flow distal to the groin. The SAM Junctional tourniquets are also capable of treating injuries at the waist thanks to an air-fillable bladder hidden under the nylon mesh.

From the manufacturer's website:

The SAM Junctional Tourniquet offers a simple design. It is compact, easy to use (only four steps), and quick to apply (typically under 25 seconds). The Target Compression Device (TCD) is placed at or near the injury site and pumped up until the bleeding stops. Two TCDs can be used to occlude blood flow bilaterally if needed. The rugged design ensures that the device stays firmly attached to the patient during transport. Designed to exceed MIL-STD-810g requirements.

SAM® Junctional Tourniquet is the ONLY junctional hemorrhage device FDA cleared to stabilize pelvic fractures. The patented buckle provides the clinically correct force every time, taking the guesswork out of tightening. This is vital in high stress environments where over-tightening or under-tightening could potentially be harmful. The SJT is the ONLY junctional hemorrhage device to provide the clinically correct force for pelvic fractures.

Indicated for:

• Iinguinal junctional hemorrhage
• Axilla hemorrhage
• Pelvic fractures

The JETT Junctional Emergency Treatment Tool from North American Rescue includes two pressure devices in a single tool. This allows for simultaneous occlusion of blood flow to both lower limbs (bilateral). It's design allows for patient transport while the device is in place. Additionally, it includes a lanyard and toggle solution to ensure that the windlass axle does not loosen due to vibration or bumps during transport.

In cases where there are bilateral injuries, the JETT offers a simple, safe solution for occluding blood flow to both lower extremities. High extremity wounds in the thigh/groin region where tourniquets cannot be placed or are less effective require equipment such as the JETT Tourniquet to stop the bleeding.

From the manufacturer's website:

• Compact, lightweight & ruggedized for use in the tactical environment
• Pre-assembled, Ready-to-use & Easy-to-apply at or near the point of injury
• Simultaneous Occlusion of blood flow to both lower limbs that does not impede Respiration
• 2 Compression Pads, pre-positioned and individually adjustable, allow for individual or bilateral activation, based on the patient’s injuries
• Cleared for 510(k) by the FDA

> SWATT

Essentially a simple elastic tourniquet, the SWATT can be wrapped around limb tightly, fully stretching it at each wrap so compressive pressure is applied. The end is tucked into the wrap.

From manufacturer's description

• The SWATT name provides a description for usage Stretch, Wrap, and Tuck. In addition it also refers to the communities for whom it was developed – military and civilian Special Weapons and Tactics teams.
• It allows a more rapid means to control extremity bleeding & allows application higher into the groin and axilla than other tourniquets
• Easy to apply
• Individuals can effectively apply it in seconds
• The SWATT is a third of the cost and weight of other combat used tourniquets
• Durable
• It has been advanced aged and heat/cold tested
• Can apply directly over a wound as a pressure wrap

The SWATT features “Tightness Indicators” which help with applying proper compressive pressure through tightening the tourniquet. However, you should probably follow your training and make it tighter if appropriate. This tourniquet features a 4″ width. This wide footprint, with an extended application time, can reduce the risk of permanent tissue damage. However, it is more likely to work when you take your time to make the wrappings neat. In the heat of the moment, when the patient is bleeding out, it’s more likely that it will be applied in a sloppy way. This may result in less than adequate pressure on the limb, only causing venous constriction.

Application time can be around 40 seconds.  The SWATT may also prove useful on pediatric and other patients with small limbs.

The beauty of this tourniquet lies in it’s versatility. Alternative uses include:

• Holding a pressure dressing in place
• Securing a splint
• Looping to hang an I.V. bag from
• There are medics that carry a few of these in their kit for all of the other things you can do with it
• Can hold ice next to strains/sprains
• Can be used to stabilize a broken bone or joint after injury

> TK-4 Tourni-Kwik Compression Strap Tourniquet

The TK-4 compression strap features a strong woven elastic textile band (2” wide by 40” long). This can provide more strength and flexibility. It is packaged in a small vacuum-sealed pouch & is lightweight.

From the manufacturer's site:

• Easy to apply
• Incredible strength and flexibility
• In April 2007, the Navy Experimental Diving Unit compared several of the leading self-applied tourniquets on the market, including the TK-4 compression strap. Their research found that the TK-4 performed well overall efficiency and product usability.

> R.A.T.S.

It is recommended that you get at least three sequential wraps. Guys with thick legs will barely able to get two complete wraps on their thighs. There is a potential for tissue damage if the wraps are spaced too close or too far, but that is true of any tourniquet system applied inappropriately. Wrapping and stretching the R.A.T.S. requires a fairly wide range of motion

The RATS Tourniquet features a very minimal footprint allowing you to tuck this thing in places your other tourniquets won’t go. Application time is around 22 seconds for self-application to the leg & 35 seconds to the arm.

> Conclusion

Tourniquets are an important part of any first responder’s gear & first aid kit. Even if they are to be used relatively infrequently, they can be a life saver with only minor consequences if used correctly & when appropriate. These are by no means the only manufactured tourniquets available. What’s important is to choose one that fits your needs and passed appropriate safety tests.

Sources: Emergency Physicians Monthly, EMS1, JEMS, Before it’s News, BlackSheepWarrior, Gizmodo, Gizmodo Australia, JEMS