3D Printed Tourniquets are Not a Cinch

Saying that something is a cinch is a way of saying that it is easy. Modeling a thin handle with a hole through the middle seems like it would be a simple task accomplishable in a single afternoon and that includes the time to print a copy or two. We are here to tell you that is only the first task when making tourniquets for gunshot victims. Content warning: there are real pictures of severe trauma. Below, is a video of a training session with the tourniquets in Hayat Center in Gaza and has a simulated wound on a mannequin.

On the first pass, many things are done correctly: the handle is the correct length and diameter, the strap hole fit the strap, and the part is well oriented on the platen. As with many first iterations, it looks good on a screen, but in the real world, we all live under Murphy’s law. In practice, some of the strap holes had sharp edges that cut into the strap, and one of the printed buckles broke unexpectedly.

On the whole, the low cost and availability of the open-source tourniquets outweigh the danger of operating without them. Open-source medical devices are not just for use in the field, they can help with training too. This tourniquet is saving people and proving that modeling skills can be a big help in the real world.

32 thoughts on “3D Printed Tourniquets are Not a Cinch

  1. These are supplies every American Student should have!

    Tourniquet, Bullet Shield, Bandages, CPR Training Manual, First Aid Manual.

    Lets replace the 3R’s with “Resuscitation, Responding, and Repecting Authority.

    1. Its incredibly sad that I’ve had to sit here for a minute trying to decide if this this is:

      -some well placed dark humor

      -what the NRA is actually promoting this week

      1. Respecting Authority is American, not Respecting Authority is Un-American.

        Comply, Listen, Follow is American as apple pie!

        Not complying, not listening, and not following orders is unAmerican.

        You sound like a commie.

        1. You sound like you let other people think for you, since we’re throwing stones. I agree, comply when it makes sense to do so, and don’t when it doesn’t. That’s what freedom and free will are all about. Being in authority doesn’t make you right. Just look at our current administration for some prime examples.

          As to the printed tourniquets, excellent project! I hope it gets them into far more hands – and those hands learn to use them properly. Stopping hemorrhage is a skill everyone should learn. It really will save lives.

          Paramedic D.

    2. Bullet shield? You’re referring to the ballistic shields that riot and SWAT police use, yes? If things get so bad that students need to carry those, then we’re pretty much screwed, and I doubt there will be regularly scheduled classes.

    1. Why even bother with 3D printing? There are better hammers in the tool box.
      It’s not like this is a terribly complex part. Injection molding, resin casting, or subtractive methods in ABS, UMHW or some other polymer have got to be faster.
      Heck an off the shelf ratchet strap from a big box or by the container from China does the same thing with minor modification at $5 in single quantities.
      They’ve got a 3D printer, enough filament to make a hundred of these but not the resources to buy a designed tourniquet for $15 in single quantity? Surely some NGO has the funds and motivation to support their mission.

      1. You’re correct about this being cheaper and easier to make using other techniques. Dead on….in the First World.

        I’m a physician with a lab focused upon bringing 3D printing to developing countries, primarily making rehab tools and prosthetics. Some of the places we’ve gone just don’t have the resources to buy this stuff. They’re getting by with BELOW basic materials and resources. Lots of homemade and improvised materials.

        Something like this is perfect for developing countries. Small, would benefit from customization, and able to be produced cheaply.

        I’m actually going to have one of my students look into this and see what she can do.

        Storng work!

        1. So you can get a $300-1000 3D printer, miles of filament, stable power to run it for days, but not a duffle bag of tourniquets? Or ship a crate of them to a relevant NGO? I get that supply chains aren’t as convenient everywhere but this just doesn’t add up.

          1. I think the point here is that having a 3D printer with filament gives you the freedom to make things as needed and, as is the case with things like prosthetics, tailored to the purpose. You can ship a bag of tourniquets cheaper than buying a 3D printer, sure, but once the printer is there you can use it to print tourniquets as needed, or prosthetics, or tools, or whatever is need.

            Besides, adding in the cost of the 3D printer is a fallacy because it’s (essentially) a one time investment. Filament would be the main thing here, and if you’re already shipping a duffel bag anyway, why not just stuff it with filament instead?

          2. Another option could be casting old plastic bags and food containers into new items. Cheaper and lower tech than 3D printers, doesn’t require special filament, and once the skill has been learned can be used to make many kinds of items. Main problem is the need for open space (ventilation) and high heat (solar cooker / open fire), which are difficult to do in an apartment block in first world.

          3. Hi there,

            I’m one of the people involved in the tourniquet work. There are a few things to note here in the context of Gaza that apply in many other places. Gaza is under a severe Israeli-led blockade. After the first 3D printer was made, we used it to make other printers. They cost about $300 a piece for Prusa MK2/2.5 replicas. We salvage steppers, make as much of our own extruders and electronics and usually just have to acquire steppers and arduinos from outside, which is tricky anyway.

            We get 4 hours of electricity, so we use solar power to power the operation. Gaza has a nearly 100% plastic recycle rate, so we extrude our own plastic from shredded material mixed in with whatever virgin ABS we can get our hands on.

            While medical supplies are not supposed to be stopped by the blockade, they are. CATs would have cost $50 a piece to get in, and there would be no guarantee of arrival – lots of similar tools have not. CATs are not usable on pediatric populations either, and half of Gaza’s population are kids. I would note that if you RTFA, all of this is in there.

            As well, creating a local manufacturing sector for medical devices is its own benefit, as it trains up biomedical engineers, encourages innovation, and puts Free/Open Source devices into the market. Now that we made it and literally field-tested it, people everywhere can benefit.

            Why 3D printing? Injection molding factories are usually among the first to be bombed, and are easy targets, as they are big, usually in industrial areas, etc. We are trying to develop desktop injection molding, but that will take time and we didn’t have it in preparing for what we all knew would be a disaster scenario.

            tarek : )

  2. The big problem here is speed. If you want to get these in the most hands in the shortest time frame, 3D printing is about the last technology you would want to use. There a simpler more effective designs that are cheaper and fast to manufacture. Another solution in search of a problem.

    1. Agreed. The Eagle Scout in me had this situation pop in my head:

      Me: He’s been shot… help me get started treating.
      Other Guy: We’ve only got the wrap! Do you want me to fire up the 3d printer?
      Me: Hand me that…

      1. Whoops… missing the context I put in. Reformatted:

        Me: He’s been shot… help me get started treating. (Proceed to apply bandage and wrap for a tourniquet)
        Other Guy: We’ve only got the wrap! Do you want me to fire up the 3d printer?
        Me: (looks very puzzled, then points to a stick on the ground) Hand me that…

    2. I’m curious what your proposed solution is. As one of the people working on this, I’d love to do something easier, cheaper and less dangerous than what we’re currently doing. It would be nice if your solution were appropriate to the context we’re working in. For more background on the rationale, the linked article includes the ‘why’ of this project that might help clarify why we’re not total idiots.

      tarek : )

    1. By way of update, we’ve had zero failures in the past ~400 deployments now. We can’t get good data on failures for the premium brands, but the general perception among those I know who use them is that it’s around 10%, so it looks like we’ve likely achieved parity.

      tarek : )

  3. you don’t need a plastic rod to make a CAT style tourniquet. you can use other materials that are already round and handy. the other part is the CAT needs velcro. which is a great idea if you’ve got time to sit around and sew up these things but if you need a real battlefield expedient, you’re not waiting for 3D prints and sewing up some cinch and twist parts. Ive got 4 of them in my trauma bag right now, and Ive been on training where instructors have personally broken the sticks in the heat and adrenalin of a first responder situation. If youve got time to sew up the proper cynch buckles, and the velcro and the hook to hold the twisted stick, and 3D print it all, you’ve got time to make MORE without the “oh look 3d printing” angle.

    And for $50 to a war zone? thats a pretty good deal considering the realities of logistics into interdicted areas. I pay over half that with shipping here in California. But if I were throwing bottles and launching rockets at well armed and fixed defenders, I would be looking for a locally sourced design that catered to what I had available and could be produced without significant overhead.

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