The 3D printed Endobronchial Trainer
Growing the Idea
It started with a conversation with Dr Jim Du Canto; the airway S.A.L.A.D. guy. In the course of recording a Jellybean podcast, he said “Do something that outlives you” – That was the seed.
I had already been making the transition to in-situ simulation, courtesy of people like Dr Jon Gatward. – That was the soil.
And Dr Ciaran Mc Kenna had just given a talk at SMACC Dublin about how he had explored the potential of using 3D printing to make a just-in-time patient-customised laryngoscope. – That was the watering can.
Like so many projects, a few different things came together to spark an idea that became a two year journey of learning and creation. Anyone who has run a sim training program will have had to deal with the challenges of model fidelity and the cost of replacing consumables. Nothing comes for free in this world.
Part task trainers may not have to be high fidelity but there is a baseline level of realism that separates a useful learning experience from “You'll just have to imagine that this is real”. In addition, many part task trainers are damaged in the process so that the person who gets the best experience is usually the person who is first to attempt the task. Many of us will have been to a skill station where the facilitator moves the model around a bit for the next participant but that IO drill, or the intercostal catheter just follows the hole that the previous two people made.
It seemed that there should be a better way and that 3D printing, also known as fused deposition manufacturing or additive manufacturing, might be at least part of the answer.
And plenty of people have had the same thoughts. A/Prof Laura Duggan had a Cric Trainer built to go with the Airway App Collaboration that she is part of. Dr Jas Coles-Black and Dr Jason Chuen set up the 3DMedLab at the Austin in Melbourne to use 3D printing for vascular surgery planning and vascular procedure training. Dr Andy Buck, who has spent years building models in his shed for his ETM course bought a 3D printer and used it to print a cric trainer and neck model that he paired up with Drs Nick Chrimes' and Peter Friz's Vortex Approach decision model.
3D printing is still a bit like the early days of the internet. File type standardization, software and model range is still being established. If you can find a suitable model (Here's an archive list from All3DP.com), go ahead and download and print it. Some models are free to download, some charge a fee for use. However, often the model either isn't there or isn't quite right, so early on it became clear that if I wanted a stock of part task trainers, I was going to have to create them myself.
3D printing has some advantages and limitations that are worth briefly reviewing to help explain why it might be a viable model option.
The set up cost is not cheap per se, but the running costs are substantially cheaper. You can buy a desktop 3D printer for between AU$500 and AU$5,000. Cost offset comes with a print quality and time offset. Print filament costs AU$30 – AU$150 depending on the material characteristics. A lot of the software needed is free.
Once you've made the initial outlay, the running costs are filament restocking and the occasional printer nozzle or build plate replacement. Depending on what you are printing, individual task trainer models can cost between AU50c and AU$10 to print. Time becomes the major investment as some models can take multiple hours to print, which is affected by the quality of your printer, the filament material and the volume of the model.
One of the biggest advantages of 3D printing is the complexity of the model that can be printed and the associated ability to customise. There are several ways to generate a printable model, including scanning, DiCOM segmentation (yes, the same method used by radiologists to produce those mesmerizing vertebral fracture and cerebral vascular anatomy diagnostic images) and CAD software. Again there are pros and cons to each of these, which is a discussion for another time.
Having played with DiCOM segmentation for a bit, I ended up going down the CAD route (computer aided design; think car parts, architecture and circuit boards). With no former training or experience. Straight up blank sheet of paper. And what better way to learn than to dive in deep and pick out a complex organic shape like the pulmonary tree. Good choice.
3D printed cric and intraosseus part task trainers for the in-situ sim training at the 2018 WRC Rally Australia
Critical care for massive hemoptysis is challenging (see EMCrit Episode and the IBCC Chapter) and not commonly encountered. So like the emergency surgical airway (“cric”), it's a procedure that needs to be trained for, preferably not while resuscitating an actively hemorrhaging patient. There are plenty of workshops and part task trainers for the ESA, so why not massive hemoptysis? And I figured it would pair up well with Jim's SALAD Sim teaching.
So I sat down to design a bronchial tree that could be used to train practitioners the essentials of driving a bronchoscope, something we do fairly commonly in our ICU and it helps that one of my intensivist colleagues was an interventional respiratory physician in a previous career. I figured that it would be fairly straightforward to then hook up an infusion set at the base of one of the pulmonary branches for a massive hemoptysis or pulmonary edema simulator.
That was eighteen months ago. Simple, huh?
Countless hours learning how to use Fusion360 (a fantastic CAD program made by Autodesk that comes with a host of helpful YouTube videos), MeshMixer (a free 3D model editing program also from Autodesk) and the basics of how 3D printers work, resulted in several versions of what is the current model of the Endobronchial Trainer. The handy thing about going down the CAD pathway is that I now have a completely clean, original model (No IP or copyright issues) that I can tinker with to set up a variety of anatomical challenges, from endoluminal tumours to airway diverticulae and aberrant bronchial origins.
The ENDOBRONCHIAL Trainer
The Endobronchial Trainer can be downloaded here under Creative Commons licensing.
I've ‘scoped it with a size 4 Ambu A-scope (6.2mm external diameter), so anything of a smaller caliber would be no problem. Stick it inside a shoe box, grab your bronch' and get practicing.
If you want to explore a bit more of 3D printing and how it is being used, hop over to Gutenberg's Grandchild on LITFL where a couple of us are slowly building an archive of resources.
References and resources
- JellyBean 051 with Jim DuCanto (LITFL) – https://litfl.com/jellybean-051-with-jim-ducanto/.
- In Situ Simulation (LITFL) – https://litfl.com/in-situ-simulation/.
- Stop complaining, start making (SMACC) – https://smacc.net.au/2016/10/stop-complaining-start-making-3d-print-your-own-sim-stuff/
- The Airway App Collaboration – http://www.airwaycollaboration.org/
- Benefits of 3D Printed Models in Vascular Surgery (3DPrint.com) – https://3dprint.com/245697/interview-with-jasamine-coles-black-benefits-of-3d-printed-models-in-vascular-surgery/
- Andy's cric trainer and neck model – https://www.thingiverse.com/thing:2530474
- Printable 3D model archive list from All3DP.com – https://all3dp.com/1/free-stl-files-3d-printer-models-3d-print-files-stl-download/
- EMCrit Podcast 199 – Management of Massive Hemoptysis with Oren Friedman – https://emcrit.org/emcrit/massive-hemoptysis/
- Severe hemoptysis (IBCC) – https://emcrit.org/ibcc/hemoptysis/
- Jim's SALAD Sim teaching (EM Crit) – https://emcrit.org/emcrit/having-a-vomit-salad-with-ducanto/
- Fusion360 CAD software – https://www.autodesk.com/products/fusion-360/overview#banner
- MeshMixer – http://www.meshmixer.com/
- Gutenberg's Grandchild on LITFL – https://litfl.com/gutenbergs-grandchild/
Matthew Mac Partlin
- Critical care physician (ICU, ED)
- ICN, LITFL, Rollcage Medic, Jellybean Podcast, Thingiverse
- LinkedIn if you really want the full dose: https://au.linkedin.com/in/matthewmacpartlin