I’m sensing some concerns over the recent explosion of 3D printing help to combat COVID-19, and thought it best to lay them out for your consideration.
The virus has now spread to virtually all countries on the globe, and as such medical capacities are being tested severely. This pressure specifically manifests itself in equipment, facility, consumables and staffing shortages. A hospital might find itself without any beds, swabs, masks or ventilators at any moment.
Today is quite a bit different from the past, where production occurred only in vast centralized factories. Today we have, in theory, the potential to leverage modern systems such as open source, networking, 3D printing, design tools and expertise to address some of these shortages. Well, at least the equipment shortages; 3D printers cannot yet produce biological reagents or new patient beds.
Because of this and a tremendous spirit of assistance flooding the world, many people are volunteering to help out in any way they can, particularly in the 3D printing world. I am all for this, but after some thought realized that everyone might want to be a bit more careful. We’ve included cautions before, and now is the time to take a closer look at some of these concerns.
Here’s a list of some things you may not have considered when trying to provide assistance:
The spirit of volunteering is so strong there are dozens of online communities attempting to coordinate activities. We reported on some of them earlier. Today there are even more, and there will be more tomorrow.
It’s impossible to help all of them, so you have to focus your attention on one or two. But which ones? None have yet “taken the lead” and become the obvious central authority. It’s quite confusing at times. One Slack system I joined was swamped with messages of people volunteering various skills, but there was little to coordinate them.
It would be much better if a couple of clear leaders emerged or were designated by the authorities. In the meantime, choose carefully.
Sterilization and Temperature
Non-medical folks often forget that everything in a hospital ICU must be sterilized. This is most often done by subjecting the equipment to high temperatures or in rarer cases chemical treatment. This is quite natural and has been done in hospitals for a very long time.
But the most common 3D printing material is PLA, which actually has terrible temperature resistance. If you were to provide a PLA part to a hospital, it could distort terribly if sterilized with their usual methods.
Similarly, many common 3D printing materials have poor chemical resistance. Do you know if the part you just printed won’t weaken when exposed to certain chemicals used in medical procedures? Do you even know which procedures are done?
It’s likely that only certain 3D printing materials might be suitable for many applications. I’m thinking ULTEM might be appropriate, but that cuts out many 3D printers that can’t reach those temperatures.
Medical staff in ICUs are covered head-to-toe in sealed suits to avoid contact with the virus. This is critical, because if they fall ill, the hospital’s capacity (labor-wise) drops.
But what if the 3D printed part you provided to the hospital has a sharp edge on it? What if that sharp edge poked a hole in a mask or rubber gloves? How can you guarantee there are no sharps in your design? Or in your 3D print?
One of the prime shortages is ventilators, which are used to assist patients with respiratory issues. Some have suggested building ventilators with 3D printed parts, which could be a reasonable thing to do.
I’m especially interested in the “splitter” designs where a single ventilator can be made to service two or more patients by splitting the airflow.
However, airflow is a tricky business. Filament-based 3D printers produce parts with visible layers. These layers can certainly interfere with proper airflow and it’s probably true that only very smooth prints should be used for such parts. That cuts out a large range of 3D printers. However, they could be used to produce non-ventilation parts, if properly coordinated.
There’s also the issue of surface porosity providing areas for bacteria or viruses to rest.
Many 3D printing materials are not certified for contact with humans. While many people handle 3D prints, it’s quite different if they are exposed to skin for extended periods of time. Recently we learned that Rize has produced a filament material that is certified for human exposure — for 24 hours only. That tells you something about the toxicity of other typical 3D print materials when it comes to long-term contact.
This means that the majority of 3D print materials may be not suitable for use in medical situations. However, once again mechanical parts are probably okay.
In an effort to figure out what can be done, I fear that many earnest volunteers might be interrupting the important work of medical staff, who are already overwhelmed. This is probably not a good thing, particularly as the required parts are often not yet identified.
I’m not sure how to solve this dilemma, but unless you are certain you have a proper capability for producing parts (e.g., the items above and much more I haven’t listed), then you probably should not be interrupting medical personnel.
There is the unknown. Most 3D print volunteers will not be medical staff and thus will not know all the possibilities of things that could go wrong. Therefore, things will go wrong. One way to overcome this is to involve actual medical expertise in discussions and designs to ensure all known issues are overcome before proceeding.
I know many of you are now scrambling to help, and I ask that you do so in an orderly manner and don’t inadvertently make the problem worse. Ask questions of experts and make sure you’re doing the right things before proceeding.