It’s a sad statement on the modern world that even civilians are at risk for severe traumatic injuries in the course of going about their lives. And if something unthinkable happens to you or someone you love, here’s hoping both that the injury can be treated, and that someone is nearby who both knows what to do and is properly equipped to do it.
That’s the thinking behind these 3D printed tourniquets, an unfortunate but necessary response to the ongoing war in Ukraine. To get tourniquets into the hands of those trained to use them, [3DPrintingforUkraine] is working on plans for a printable version of the C-A-T, or combat application tourniquet, a lightweight but strong tourniquet that can be rapidly applied, even by victims themselves. The commercial device consists of molded nylon buckles and hook-and-loop fastener bands, along with a very sturdy plastic handle that serves as a windlass that provides the necessary occlusive force when twisted. The 3D printed version’s parts aren’t as streamlined as the commercial unit’s, but they appear to be strong enough to withstand the considerable forces involved. From the look of their site, STL files and instructions for assembly will be available soon.
To be clear, tourniquets should only be applied by someone properly trained to do so. But having ample tourniquets available where traumatic injuries to the extremities are likely to occur can only improve the odds that one will be available when it’s needed. So hats off to [3DPrintingforUkraine] for making the effort to push this forward.
[Austin Everman] sent us this tip. Thanks!
The first rule of a tourniquet is to never use it. You can cause multiple injuries while using it (even if done right!). Installing a tourniquet means you’re giving up in saving the member. You are likely not educated enough to know if a member is still viable or not. If you install a tourniquet with too much force, you’ll likely cause immense pain by crushing the viable cells and blood vessels under the tourniquet and liberating huge amount of dead cells in the blood stream. If you don’t use enough force, you’ll increase the blood pressure and likely allow pathogen to reach the main blood stream faster.
Also, never remove a tourniquet (even if you installed it for few seconds) since doing so will cause a direct contact of pathogen to the blood stream.
Once you’ve installed a tourniquet on someone, you need to bring this person to immediate healthcare. If it impairs his ability to move by itself, you’ve a dead horse to move.
In short, before even dealing with this kind of things, it’s absolutely necessary to get some courses about this.
That may have been the medical knowledge once upon a time, but I am happy to inform you that use of a tourniquet is no longer an automatic loss of limb, in fact far from it!. The military and law enforcement agencies with current training now teach to use one early and often if there is any risk of death by exsanguination(bleeding to death), which can happen astonishingly quickly.
After 20-odd years of war in Iraq and Afghanistan, there are now robust procedures to gradually remove tourniquets in a way that preserves the limb. The major risk of removing the tourniquet stems from essentially bursting blood vessels with the rapid reintroduction of blood to vessels that have been drained. This process should *absolutely* only be done by a credentialed and trained medical professional in a very controlled environment.
The only major limitation now in the application of a tourniquet is that it is essential to mark the time it was applied on the patient. Many commercial products also feature a clip to keep a dedicated sharpie marker for this specific purpose. The time it was applied is an essential part of calculating the process of safely removing the tourniquet and saving that limb. However, it is worth noting that the upper limit of how long a tourniquet can be applied before losing a limb is measured in hours and not minutes. Get them to higher levels of care, but don’t rush in a way that risks further injury to the victim.
If you are uncomfortable with any medical procedure, as a lay person of course you should never perform it. But for those who better themselves with an introductory trauma medical course, the use of a tourniquet is absolutely recommended in any case where exsanguination may occur, through either internal or external bleeding.
It’s worth noting that this also goes for crush wounds. If you find someone crushed under something, your immediate instinct is to get them out ASAP! But if they’ve been there for more than a few minutes, that might make matters worse, so get trained medical help first. I believe there’s injections they give before removing the pressure.
Really interesting point to consider, thanks for sharing!
Well yes, and no. If there for a while, the extremity or area pinched would have blood flow cut off. This would in turn cause anaerobic metabolism creating lactic acid and other things. Once the thing causing the crushing is released, that acidic blood would rush to the core and essentially shock the system. So, sodium bicarbonate is given to reverse the acidity(in lack of better terms) calcium administered and albuterol administered. You also in true crush have hyperk, and this can cause cardiac arrest, so calcium stabilizes the myocardium. This is all for a crush injury. With a tq, it is safer to apply. The guy originally making the post against tq use is completely wrong with todays studies. Blood loss will kill a lot quicker than anything he listed…
This is also only untrue without context. Those 20 years of conflict are as you say with the US military. The successful use tourniquets in field medicine depends on the entire infrastructure of combined operations as well as advanced care field hospitals being available. These are not resources that places like Ukraine, or a lot of rural EMS has to rely on.
When you don’t have the guarantee of a dedicated high end team flying your patient immediately from the field to an advanced care facility that limb is done as soon as you apply a tournequette. In those instances other methods of blood loss prevention should be attempted before that one.
The level of “advanced care” needed involves a surgeon being able to do something about the injury that necessitated applying a tourniquet in the first place; the blood chemistry involved isn’t something that is going to get fixed in the back of an ambulance, but it’s pretty trivial once you have an operating room. This is also going to be true of any other kind of blood loss prevention.
Of course, if you are unlucky enough to suffer a 5.45x39mm or 7.62x54mm round to a limb delivered by a liberator, the first priority is to prevent death by massive exsanguination, and the tourniquet will do that while waiting for medical help.
In the operating theatre, inflatable cuffs can deprive a limb of blood flow to provide a bloodless field for the surgeon for many tens of minutes, up to 2 hours, quite safely without affecting limb viability.
Reperfusion injury and shock after prolonged use can be an issue on release, however.
A good summary on use and precautions:
https://www.cambridge.org/core/journals/canadian-journal-of-emergency-medicine/article/prolonged-prehospital-tourniquet-placement-associated-with-severe-complications-a-case-report/E5EE2FAFB1D5CBBE2BBC23F6F849505D
Really good article, bookmarked for later reference.
Dude as a certified EMT and professional in the area let me tell you some truths about the tourniquet. First of all. Tourniquet saves lifes and is the first thing to use on an important bleeding if you have it available!!! And what you are saying about pathogens and stuff what??? It is not crushing nothing but constricting the blood vessels that supply the blood that is coming out of the extremity and therefore putting that person at risk and it causes no harm you can put a tourniquet safely on an extremity for 6 hours and still cause no harm cause that’s how long your muscles and bone can stay wpthpit pxigen before they start to have permanent damage. Also the reason why you should not remove it after you place it is actually because that is what is avoiding that person from bleeding to death and also it must to be removed in an hemodynic room by a doctor who know how to do it is actually because it may cause blood clots that can travel through your body and then cause problems but doctors know how to avoid that and you can save someone’s life and someone’s extremity so there you go! You are welcome.
So what’s the plan? Churn them out in North America, and then have to get them over there? Seems like traditional manufacturing beats that.
Or maybe it’s intended for people over there to use their printers to make on demand. But that requires printers, and maybe not the best use of resources.
The churches here are getting overwhelmed with donatiins. People”wanting to help” and nobody wanting to turn them away. But unless we get a big influx of refugees, the donations are only useful if they can get to Ukraine, or nearby countries taking in refugees. And that costs money, for a near random selection of items.
Best to donate cash, which is way more transportable, and can be used close to where it’s needed, and used in ways the situation demands.
If you’re in the US you’re probably best giving cash.
But in Europe, getting supplies out there is worthwhile. Friends at our church are just on the way back from driving a van full of medical and other supplies to a church in Poland, where they’ll be used for refugees, and taken into Ukraine by some very brave Polish pastors.
We quickly collected a huge amount of high-quality medical supplies as during Covid, the NHS was leaving boxes of dressings with people and not taking anything back for fear of contamination.
Around here (small town somewhere in western Europe) some products (veg. oil, sugar, noodles, toilet paper, some canned goods) are gone from stores and I’m told not all are missing because off panic buying, some shelves are emptied out because people want to help and donate it.
Despite the good intentions I think this is still a bad idea.
All those goods get shipped here by truck and then get packed together again by volunteers and loaded onto other trucks to send them to eg. Poland. And the usual resupply shipments to here may get screwed up by these sudden changes in demands (but I think the distributors know that so it’s probably more a theoretical proplem).
Donate the money directly eg. to the international Red Cross/Crescent.
Donate to the help/relieve organizations already working there who know what’s needed and when & and let them buy the stuff in bulk through their established channels and delivery chains.
If on the other hand there’s a need for eg. warm clothing, sheets and sleeping bags and you already have those at home and don’t mind donating them it makes much more sense to donate that.
Hi, this is Jakub Kaminski, 3DPrintingforUkraine.com (founder, R&D lead). We have several medical professionals supporting the project but we abstain from media attention/articles unless very strong evidence is published.
Donating to organizations who have good logistics is a good idea, so find a trusted one that delivers directly to those who need the support.
There is a shortage of tourniquets and the lead time for the good ones (CAT) is too long, which is the reason for 3D printed initiatives. Don’t but things that are named “CAT” and do not come from the official NAR reseller, there are numerous counterfeits on Amazon that look exactly the same but are unsafe. I show how bad these Far East conterfeits are in one of our videos on the website.
I wish my team had a chance to have contact with Hackaday before we learned about this blog post. I think that some unfortunate miscommunication happened. Nevertheless, I encourage you to revisit our website in a few days to see more updates.
Giving tourniquets is taking someone’s trust. Please beware of 3D printed tourniquets that are NOT field-tested by soldiers themselves or don’t have precise sewing documentation.
I will be happy to share with you the project updates, as we finalize all the tests. Could you email me at: jkaminski@wpi.edu to stay in touch? Thank you.
The plan is to 3D print them, preferably in a distributed manner in Ukraine itself, and then get them to where they are needed. The plans being planned to sent out (I’ve seen them as I’ve been in contact with the projects designer here in the US) says the number one thing they need is petg filament, so I figured that the best way to maybe get them the help they needed was to spread the word here on HaD. They have a distribution node in Poland where they can get these sent over as well, so if there were ones being made outside of Ukraine, then there’s still an option to have collective help make them and get them to where they need to go.
So the plan is to ship filament? Using very limited logistics resources into Ukraine?
Seems like shipping in injection molded versions would be a better us of resources. Or just good solid chord by the spool.
I strongly advise you not to use and promote 3d printed tourniquets. The reason is that its really hard to manufacture a safe (in professional hands) tourniquets, and it takes a lot of testing by medical professionals. Problems can be within hard parts as well as soft ones, and ANY inaccuracy in materials used, in how they stretch or not or flex or break – costs a life or a limb to the injured person. And 3d printed tourniquets make a false feeling that demand is covered, and no need to buy certified ones. So please, just please – leave tourniquets manufacturing to organizations who can arrange testing and proper certifications. Individuals – can’t.
Guys, i’m begging you – don’t waste plastic on that crap.. You are putting the person who will use it in great danger. We have conducted a large number of tests on printed tourniquets -most of the tested designs have failed.
And in emergencies, we don’t have time for a second try! If this tourniquet did not work, then the person who relied on it would most likely die.
Hi all,
As an addition to this post.
I’ll like to share the work done by the glia community (used in gaza)
https://glia.org/
https://trklou.medium.com/glias-gaza-tourniquet-is-ready-for-emergency-use-in-ukraine-make-some-if-you-can-ef5f83260b7c
Best
i feel like this is in an awkward middle place…the benefits of a mass-produced industrial tourniquet with all the fine details of its design probably can’t be denied, but also a stick and a bit of fabric works too. that is, if you need a hacked version in a hurry, or if you anticipate the need for a larger number of tourniquets than you have on hand, your obvious solution is to use more traditional ad hoc manufacturing techniques. it takes a pretty weird circumstance where a 3d printed one makes sense, since the mechanism is so simple.
I had to check the date twice as this is such a silly idea. No matter how many tourniquets are printed on the other side of the globe, they won’t magically pop up in the hands of wounded soldiers and civilians when they are shot.
If you really want to help and are too far away from Ukraine to do it directly, cut down on energy consumption, even if you are in the US. Russia is financing the war by selling fossil fuels, every barrel and m³ not sold weakens Putin’s gang.
Alternatively, you can increase ‘your’ production of energy of all kinds. Which works just as well to weaken Putin’s gang.
I’m looking at you Europe, get fracking. ‘Don’t make us come over there again.’
When the USA is the adult in the room, you know you fucked up.
Netherlands here. They finally approved a plan to build two nuclear power stations. Fracking won’t help us here. We have huge gas fields which we can just hook a pump onto without fracking, but so far, they refuse to do that because it increases earthquakes. Meanwhile, our eastern neighbors, Germany, are closing down nuclear power plants to go back to brown coal, because of the environment for some reason I don’t understand.
https://www.thingiverse.com/thing:5282549
I think the glia one is probably better.
https://glia.org/
It has been tested in Gaza. It is fully documented.
But probably cash to aid agencies would be better.
“I support !”
People are programmed \*far\* too easily.
We wanted to print this, but medical profesionals warned us that this is a nonsense and dangerous one. With 3D printed tourniquet you can cause more damage than help, even cause death.
Given the option of using an existing design (the ‘glia gaza’ one that has already had a couple years of field testing by medical professionals), I suppose my first question would be “why reinvent something that can cause someone to die if you get it wrong?”. (I guess it’s like the people with no background in medicine who were absolutely convinced they could print ventilators two years ago…)
And as a first responder to a military base, as well as someone who does training for workplace active shooter response… I’ve used a Glia Gaza (because it’s something that students bring up), and while it’s better than an improvised stick-and-scarf one (if made _exactly_ per their directions), I still wouldn’t recommend it over a (real) NAR CAT. The reason the real CATs are expensive is because they do extensive and ongoing QA on production, so there’s never any ‘oh, I guess my filament got wet’/’yeah, there must have been a draft on the print plate’/’ok, so the surface finish isn’t great but I’m sure it’s fine’.
If they want a 3d-printed tourniquet, the Glia Gaza design is out there and reasonably well known. Making their own seems kinda like the guys with no background in medicine trying to design ventilators 2-ish years ago.
If they want to knock off a commercial design, the MET is probably going to be a better one (due to using a metal bar with a slot in it as a windlass); this wasn’t viable in the Glia design due to the difficulty in getting metal stock in Gaza (especially machined metal stock), but that bar is a pretty simple thing that most high school shop classes could churn out in volume.
They seem to be in plentiful supply at AliExpress.
I’m torn. I have the training to apply a tourniquet (CAT), and mechanically they are well-defined and actually pretty simple, therefore pretty easy to replicate. However, the distribution problem is the same whether they are 3D printed or factory made.
Should I print one, put it in a package labelled “Ukraine” and post it? Should I buy a roll of PETG, put it in a package labelled “Poland” and post it? Should I raise an order with AliExpress for CATs or PETG, for delivery overseas? Or should I give some cash to an aid agency?
As I see it, this design is great. Much like the 3D printed stethoscope which was released a couple of years ago. But it only works in the situation where “I can’t buy, or can’t receive, factory goods, but I have a 3D printer and supplies right here, and I have logistics to get the printed parts where they need to go.” This is such a specific niche case that I can’t imagine it is common. Is it?
Cynical as it might seem, hostilities are occurring in only one place. And despite the pandemic, goods are still circulating around the rest of the world. Acquiring manufactured CATs should be much easier than printing them. But, I’m not there, so I don’t know.
A lot of the ones on AliExpress are knockoffs. Lest I be accused of being anti-Chinese, so are a lot of the ones on eBay and Amazon. Pretty much any CAT you pay less than about $30 for is a fake, and if you’re having your order fulfilled by a company that also sells fakes, odds go way up you’re paying MSRP for a fake. Medical supply houses tend to be a bit more expensive, but they also can document the providence of their wares.
Legit CATs are readily available in pretty much any volume you want, but even in significant volume, you’re still going to pay $27-28/per for them, because you’re running up against NARs non-recurring costs. (It’s not that the parts are expensive. The QA is expensive. As is insurance associated with manufacturing medical devices.)
The claim to fame of these guys is that they’re cheap and much closer to the business end of the logistics chain (both of which are important), but there’s not a lot on their website that inspires confidence that they have the biomechanics background for what they’re designing.
I have made a number of CAT devices using the STL’s and instructions from Gila medical. I made mine from ABS and PLA and found both worked acceptably, quickly and easily making my pulse undetecable in either arm or leg. The strength of the PLA version was greatly increased by oven annealing the plastic . If you can properly print PETG or Nylon those would obviously be better. The biggest difficulty is hand sewing the pressure band, which is long and composed of two pieces of thick nylon too heavy for my sewing machine. I have shown my work to some military medics of the “no you can’t take my picture” variety and they pronounced them acceptable.
Note that these are one use devices, repeated uses will cause them to break, but they are not meant to be reused.
All that said, I think that unless you have a print farm and a means of delivering these to Ukrainian forces, it is better to just send money.
This is really people attempting something out of a good feeling, but wasting effort and expense. IF a tounequette is necessary materials to make one are readily available nearly everywhere.
This has also been discussed on the Open Source Medical Supplies FB group. As others have also noted, GLIA is the authority on 3D printed tourniquets. The project and design pictured in the article are well meaning, but misguided:
https://trklou.medium.com/reinventing-3d-printed-tourniquets-for-ukraine-is-a-mistake-be2937f0ad65
This is medical equipment for an acute and serious situation, not at all like the face shields of 2020 that just-kinda-need-to-be-comfortable-enough. There is already a proven design out there. At best, taking shortcuts in the name of “printability” is just wasting time and resources.