Tourniquets are one of the most important emergency preparedness supplies you can include in your survival kit. Check out the article below for more information on the different types of tourniquets.
Emergency Preparedness Supplies: Introduction to Tourniquets
If a person has arterial bleeding, it must be stopped immediately or the person is likely to bleed to death (exsanguination is the technical term.) If the wound is on an arm or a leg, a tourniquet is currently the most reliable way of stopping the bleeding, at least by a non-medical, stressed, person. It is also the most dangerous. Once a tourniquet is applied, the limb below the tourniquet is cut off from circulation, and starts to die. In as little as two hours, and almost certainly by six hours, serious damage will have occurred, eventually making it necessary to amputate the limb. Plus, there can be damage at the site of application due to the pressure applied by the tourniquet. Why then is a tourniquet ever considered appropriate? It is that the risks/damage from the tourniquet are less than the risks/damage from uncontrolled arterial bleeding or better but more time consuming treatments.
This means that the absolute first step after bleeding is stopped, is to mark the tourniquet with the time it was applied. And the next step is to get the victim to someone with medical training and equipment ASAP, so the artery can be repaired and circulation to the limb restarted before significant damage occurs.
What then, is a tourniquet? It is a band which goes around the limb above the wound (between the wound and the heart), and is tightened tight enough to cause arterial bleeding to stop. As mentioned above, the pressure applied can cause damage at the application site. In general, the wider the band, the less tension it takes to stop blood flow, and the less damage is done at the site of application. Generally the wider, the less pain, unless the tightening methodology results in severe pinching. Thus always try to have the tourniquet be at least an inch wide whether it is a commercial one or an improvised one. Although paracord or other cords CAN be used to make a tourniquet, it would be better not to use them for this purpose unless there is no other choice. Surgical tubing can make a surprisingly effective tourniquet, but again, the narrowness can cause extensive pain and likely application site damage.
Types of Tourniquets
There are four common “mechanical advantage” types of tourniquet: pneumatic, windlass, ratcheting and elastic. These all include a mechanical method of applying tension and thus pressure. There are other “standard” types of tourniquets (such as Velcro, tied, or buckle) which can do the job if you can manually apply enough pressure, but this is usually rather more difficult. Particularly if you are applying it to yourself or with one hand.
If you have ever had your blood pressure taken, you have experienced a pneumatic tourniquet. A cuff is placed around your arm, and it is pumped up far enough to stop the flow of blood. It is simple in concept and effective, but not really optimal for emergency use. These tend to be large and expensive and easily damaged. In fact, some are even microcomputer controlled. It would not take much for a leak to be introduced, and then the tourniquet would be unable to perform its function. These are particularly useful for surgical applications, as they are easy to apply, release, control the amount of constriction, and tend to cause minimal pain and damage at the application site. There is at least one which may be usable in emergencies, the EMT (Emergency & Military Tourniquet from Delfi Medical Innovations .) If you can find one, it could run you $300 or so; too much for me. If it was more like $30, I’d certainly try it, but even if it worked as well as it seems it should, I wouldn’t have it as my only tourniquet due to the chances of a leak.
The windlass tourniquet is what most people think of when they think of tourniquets. If you have had a first aid course, you have probably been shown how to fabricate such a tourniquet from scavenged materials. Tie a strip of cloth or other flexible material around the limb, add a stick or rod to the knot and knot again, rotate until blood stops and tie the stick in position. This is not a quick or one handed process, so companies have come up with various pre-made tourniquet systems, which can allegedly be applied one handed. They are “one piece”, with a built in tension stick and way to lock the stick in place after the blood flow is halted. The most common ones are the CAT (Combat Application Tourniquet from North American Rescue) and SOFTT (Special Operations Force Tactical Tourniquet from Tactical Medical Solutions .) These tend to usually be above $20 apiece, but it is possible to get them for less, particularly on eBay. Note that the SOFTT is available in original (1″, SOFTT-NH) and wide (1.5″, SOFTT-W .) The wide version is likely to require less tension and thus be more effective and cause less damage, and it is claimed to be lighter and smaller than the original version.
The ratcheting tourniquet is like a cargo strap. The strap is fastened around the limb, and then a lever is operated back and forth linearly to apply tension. Examples are the RMT (Ratcheting Medical Tourniquet from M2 Inc) and the SATS (Self Applied Tourniquet System from Marketing Tactics .) There is one which actually looks a lot like a cargo strap (LBT from London Bridge Trading, Inc), but it appears more bulky and definitely is heavier than the other options, and with the higher price, I passed on it. In general, ratchet tourniquets seem to be a bit harder to find than windlass, and often will be above $30. There are six versions of the M2 RMT, including one for children and one for K-9s.
Finally, there is the elastic tourniquet. With this one, you just wrap the band around the limb, under tension, and fasten the end in place so it does not unravel. The RATS (Rapid Application Tourniquet System from ratstourniquet.com), TK-4 (Tourni-Kwik from H & H Medical Corp) and SWAT-T (Stretch, Wrap And Tuck Tourniquet from swattourniquet.com) are examples of this type. Generally these will be $15 or even less. Note that there is a TK4-L model which is designed to be more effective when used on the upper leg (thigh .) The RATS appears to be way too narrow, but since it is wrapped around the limb several times, it is claimed the “effective” width is multiplied.
Based on its videos, it appears the easiest tourniquet to apply one handed may be the MAT (Mechanical Advantage Tourniquet by Pyng Medical) which is unclear as to what “type” it is. It appears to be a cross between the windlass and the ratcheting types (a “ratcheting windlass” .) It has a large fixed portion which holds the device to the limb while the other end is hooked up. However, this large fixed portion makes it much larger than the others, and it probably would not be practical to carry one except in a vehicle.
When buying tourniquets, beware of counterfeits – they may be cheaper, but they also may not be as strong or as effective as the original.
Like most medical items, these sometimes have an “expiration date”, which is the way the medical community does CYA. They put on a date before which, they can guarantee the item is effective and has no unexpected negative impacts. In the case of a tourniquet, the date should be considered a guide. For instance, the CAT does not appear to have anything which would deteriorate or be subject to chemical reaction. Thus, I would not go out of my way to replace an expired CAT, unless it was many years ago or was stored in a harsh environment. The SWAT-T has an expiration date way out there, and is basically a large rubber strap. Thus I would tend to pay attention to this expiration date; I have had experience with rubber items deteriorating over time. The SATS, SOFTT, RMT and TK-4 do not appear to have an expiration date.
Trying Them Out
Volunteers to suffer arterial wounds are surprisingly hard to find, so I was not able to achieve a reliable indication on whether each tourniquet worked or not. I applied each to my thigh (two handed) and my upper arm (one handed); when on the arm, I had an oxygenation/pulse meter on that limb to give some indication of whether blood flow was blocked.
SATS – 6.5″ x 1.5″ x 1″ to 2.5″, 5 oz. This is not a true ratchet tourniquet. It is more of a “toggle”. You pull it as tight as you can, and then force the lever closed, which tightens the strap another inch or so. The strap is nearly four feet; long enough for most any limb. It is fairly easy to put it in place, however it is a rather difficult to tighten with one hand. And that is the only adjustment. It is either open or closed. It does have a slide lock to keep the lever closed, and a screw lock to keep the strap locked. If you unscrewed the screw lock (and taped it to the tourniquet to reinstall in use), it might reduce the thick end by a half inch. In my trials, it did not seem to block blood flow at the tightness I was able to generate one handed. Due to the odd shape when packed and the manual adjustment of pressure (which means if you can’t manually get it tight enough, it won’t stop arterial flow), I would not choose this one.
SWAT-T – 4″ x 2 3/4″ x 3/4″, 4 oz. This one applies pressure via elastic stretch, allowing it to be also used to hold on dressings/ice in addition to use as a tourniquet. The name is the instruction manual – Stretch, Wrap And Tuck. This is difficult to get started, as you have to overlap in order to hold the end in place, which means the first wrap is not very tight. Next, as you stretch it, it narrows, which is not critical, but it tends to be forced to fold over by the skin on each side of the depression, which does significantly reduce its width. It is difficult to wrap one handed, and very difficult to tuck the end under one handed when wrapped fully stretched. Since I could not get it tucked, I can’t speak on how easy it is to relax the tension, and I could not get it to block blood flow (one handed .) I can see how this could be improved, but as is, I would not carry it as a primary tourniquet, although I might use it to hold on a dressing or ice pack, and it could probably be used as a tourniquet when two hands are available to apply it.
CAT – 6 3/4″ x 2 1/2″ x 1 1/4″, 2.1 oz. A classic windlass, with about thirty inches of strap, so may be marginal for the biggest thighs. The primary adjustment is via Velcro, which is quick and accurate, but with the potential of slipping or being accidentally released. But it does install easily one handed or two, and seems to do the job (stopping blood flow .) It is easy to secure the tension rod under tension, and there is a white Velcro strap which not only is an additional safety to discourage unintentional release, but is set up to write the application time on it. Readily available and sometimes relatively inexpensive, this would be my top choice.
TK-4 – 3″ x 2 1/2″ x 1 1/4″, 1.8 oz. TK-4L – 2 3/4″ x 2″ x 1 1/2″, 2.1 oz. The TK-4 is an elastic strap with a hook on each end. It did not seem to work well on the upper leg; probably why they came out with a new model specifically for that. Unlike the SWAT-T, the hook on one end makes it easier and more effective to start. The hook on the other end makes it easier to fasten. I am concerned that the end might slide looser over time, since only friction holds it in place. It was not too hard to apply with 2 hands, with one hand it was a bit harder but still doable. I could not tell if it completely stopped blood flow in the arm, but at a minimum, flow was cut way down. It was more uncomfortable than the CAT. It appears that the only difference with the TK-4L is a better hook on one end, used to allow the initial wrap to be tighter. The L model feels more effective on the leg, and definitely completely stopped blood flow in the arm. It is rather more difficult to stop blood flow than with the CAT, but it can be done, and the small size and cheaper price is attractive. I would always choose the TK-4L version, as it appears to be more effective than the original one, and would use it only in kits where a bigger, easier to apply tourniquet would not be practical, or as a second tourniquet if size or cost prevented duplicating the primary tourniquet.
RATS – 6″ x 3 1/4″ x 1/2″, 3 oz. This is an odd one, in a non-standard package. You may need to take this out of the package to fit this into some kits or pouches. Both the narrow width and elastic methodology are probably why it caused more pain than the other tourniquets I tried. It is really easy to install with two hands, and the easiest to install one handed of all the elastic tourniquets I have tried. It stopped blood flow more reliably than the other elastic tourniquets, but not quite as well as the CAT. This would not be my first choice, but it would seem to be acceptable if the package size was more appropriate than a better choice.
SOFTT-W – 5 1/4″ x 2″ x 1 3/4″, 3.9 oz. Another classic windlass, with about forty inches of strap, so should be good for any limb. Primary adjustment is via a sliding buckle, which seems to be pretty secure. It is almost as easy to install two handed as the CAT, without the possible problems with Velcro. It is rather more difficult to install one handed. To tighten the strap, pushing on the buckle with your thumb and pulling the strap with the rest of the hand appears to work well. Tightening is a bit of a problem; it twists the strap around itself, and as it does so, the tightening rod tends to rise away from the body of the tourniquet, and even flop around a bit. This also can make it difficult to stick the end of the rod into the locking ring, as if the lump of twisted strap is big enough and positioned wrongly, the rod might not reach to the ring. It does stop blood flow though, and that is the key. I like the CAT better, but this will do the job.
RMT – 8″ x 1 3/4″ x 1″ to 1 1/2″, 4.5 oz. This is the “paramedic” model, which is perhaps the best compromise. It has 1 1/2″ webbing, like the CAT and the SOFT Wide; there is a smaller model (to pack in a smaller space), and a 2″ strap model (which should be more effective, but probably bigger), as well as the specialty models. The length of the strap is thirty five inches, and is held in place by a double buckle, so all of this strap is reliably usable and should be adequate for most limbs. The double buckle setup is easy to tighten and seems reliable; it appears a better solution than the large spring clasp used on some of the other brands. It does make it a bit harder to get off though. It is easy to install one and two handed, thanks to the “tactical loop” which can be held by the off hand or your teeth while the initial adjustment is set. It is important to get this as tight as possible, as there is a limited amount of tension which can be applied via the ratchet. And that is why, despite being easy to install, easy to tension and even fairly comfortable, I don’t think I’ll be relying on these. If it was not applied tight enough to begin with, and the built in ratchet when fully engaged was not enough to stop blood flow, it would probably take too long to get it off and reinstalled. And in my trial, it did take full ratchet engagement to stop blood flow. Note that they have the Rescue model with a longer ratchet, which may avoid this problem, at the cost of a bigger package.
Access to Tourniquets
In order to be effective, a tourniquet needs to be applied very quickly. Having to dig through your supplies to find it means the chances of benefiting from it are greatly reduced. So, make sure you keep your tourniquet where immediately available. In a fixed location, this would be in a readily available container, where nothing is likely to get in the way or hide it or relocate it. If there is any indication that injuries are likely, I’d stick one in my pocket or on my belt. For portable kits or scenarios, it should be in a pouch or pocket on your vest, belt or outside of a pack. There are pouches designed specifically for this purpose, although a standard universal rifle single mag pouch often works well and might be cheaper.
Adding Tourniquets to Your Kit or Preps
My first choice would be the CAT. If I could not get CATs, SOFTTs would be acceptable. In cases where size or cost were a major concern, a TK-4L or RATS would be acceptable.
As mentioned, tourniquets are a 1) dangerous and 2) very short term, interim, patch to a serious medical problem. Strictly FIRST aid. If you are going to include tourniquets in your preps, it would be wise to also include access to the long term solution to the problem, that is, a plan to access people with training and equipment to deal with arterial injuries, or getting some basic training and equipment in that area yourself.