3D Printing, Organization

Houston, This is Apollo, We Have a Problem

Our poor Dräger Apollo anesthesia machines have reached the end of their lives. Although the medical engineering department has fully acknowledged this fact, the hospital has taken their time in replacing them. Other than maintenance for critical functions, no maintenance is being performed, including replacing non-critical parts. Unfortunately, the storage drawers on the machine have had broken and missing dividers for some time. Although, in my opinion, good organization is critical to the practice of anesthesia, the hospital administration disagrees. Myself and one of our CRNAs took on the task of fixing the drawers.

I started by replicating the the missing dividers in CAD. From the original divider design and holes present in the drawer, it appeared that there used to be a clip holding the tabs down; however, I could not find a single divider that still had the clips in place. Likewise, I doubt that a 3D printed clip would last long (in an inexpensive plastic such as PETG, at least) and elected to just make a little tab that slides into the bottom drawer hole instead of a clip.

Image of model created in CAD.

The original divider had a taper to it which I replicated; however it posed a minor problem for printing. Should I print the divider flat and have a staircase effect on one side, or print upright. Printing upright would eliminate the staircase effect and would allow for more individual dividers to be printed per printer plate. I decided to go with the flat printing as the staircase effect would be unlikely to affect functionality and, from experience, printing tall, thin objects upright tends to require a lot of tinkering and is still prone to print failures. Additionally, if I decided to print many of these the, project could be spread across my 6 printers, so printing many per plate in the upright orientation was not a major concern.

The two possible printing orientations shown on the same plate. Upright (with a brim for stability) on top and flat (with staircase effect) on the bottom.

I printed the model on a Bambu P1S with 0.4 mm Nozzle in Blue PETG. The model printed easily without issues. The first version, even though it was the exact dimensions as the original, did not fit well. The horizontal crossbar/divider had developed some laxity over time which allowed the divider to easily dislodge; this also explains while the original dividers were also easily dislodged. I reprinted with 5mm extra length to the divider and this solved the problem. It may have also been that the bottom clips on the original design helped with dislodgement, but either way, my new design provides a snug fit which wasn’t easily dislodged.

Image of final printed design.
Image of dividers in place
Dividers with items in drawer

While these dividers won’t extend the life of our aging Dräger Apollo anesthesia machines, they do restore a small but meaningful measure of order to our daily workflow. When equipment replacement moves slowly, frontline clinicians find themselves engineering practical solutions to keep systems moving. This project may be minor in scale, but reflects a larger truth: that board room institutional decisions often fail our patients and the initiative of the people working directly at the bedside are forced to fill the gaps. Until our new machines arrive, at least our drawers, and our practice, can remain structured, deliberate, and ready for whatever problem comes next. Though nowhere near as dramatic, our 3D Kintsugi draws on the same mindset that defined Apollo 13: solving urgent problems with whatever tools are at hand.

3D Printing, Airway

Don’t Smoke Kids

One of my department’s intensivists, Luca Bigatello, participates in classroom outreach events teaching about common medical conditions. He was looking to integrate a 3D printed teaching model into his presentations to both garner interest from the high schoolers and minimize cost as quality medical models can easily cost in the thousands of dollars.

Luca didn’t have an exact item he was looking for but was going to be discussing respiratory diseases and gave me free reign to come up with something interesting to show.

I started by browsing the open source community for model ideas. I found a cool model from designer FHEDER on cults3D of a healthy vs. inflamed bronchi.

Model found on cults3D

I wanted to print the models as a multicolor print. I initially tried to separate the model into multiple parts in CAD to make it easy to define the components as different filament colors but this proved to be challenging due to the model’s complexity. Then I tried simply importing the solid model into the native Bambu Studio painting environment to assign filament colors. The function was very easy to use and lightyears better than other products I had used.

The Bambu Studio painting environment is straightforward and a breeze to use for designing a color print.

After planning the model coloring in Bambu Studio, I set the model to print on a Bambu X1C with 4 colors of PLA loaded into the AMS (Automatic Material System) and printed the models at 0.2 mm layer height.

The models came out nice and Luca was happy to take them. He stated that the it was a great addition to his talk and the fact that they were 3D printed increased the interest level among a number of the students.

3D Printing, Anesthesia Equipment

Hooked on You

Positioning the operating room table for intubation and line placement for ourselves, and optimizing operating conditions for the surgeon is a seemingly minor yet extremely important part of the anesthesiologist’s job. An OR table controller with a broken clip can lead to a much bigger headache than one might think, causing the controller to fall to the floor constantly and add frequent 15 second delays every time the table needs an adjustment.

Some of our OR tables have chronically broken clips, no doubt by planned obsolescence, to encourage purchasing a constant stream of $50 replacement clips from the manufacturer. Exhibit A:

Due to the slow response time of the powers that be that should be replacing these clips, I took it upon myself to design and 3D print a replacement clip, that was both cheaper and stronger. Here is the 3D printed model that I came up with:

I made the clip much thicker than the OEM product to hopefully reduce the incidence of breakage. I printed the model on a Bambu X1C in PAHT-CF filament (Bambu Labs’ blend of carbon fiber reinforced Nylon) at 0.3 mm layer height with 60% gyroid infill and 4 layer shells. Here is the final version printed:

Anecdotally, the clip feels robust and was able to support my weight when stepped on. Here is the clip in place:

Now that I have an effective model that can be printed in about 45 min, we no longer have to worry about the OR table controllers going for months falling on the floor constantly due to the lack of a clip. Will this new clip tolerate being crashed into by a 1000 lb. ICU bed? Only time will tell.

3D Printing

Its a Sign

The chief of my department approached me about the lack of a sign on the intensivist’s call room.

Rather than wait 6 months for facilities management to provide a new sign he requested that I design and 3D print one instead. Since the call room is in a non-patient accessible area, I decided to add some mild humor to the sign. Here is the initial design that I came up with:

To make this a quick project I utilized some open source resources. I obtained the defibrillator SVG pictogram from freesvg.org where it was listed as public domain. I utilized the free to use IMAGEtoSTL converter to convert the SVG file to STL, then imported into my project. I could not find quality ECG vector images of ventricular tachycardia/sinus rhythm so I imported some ECG images into photoshop and isolated the lines; I then used IMAGEtoSTL again to produce STL images of the rhythms and imported into my project. This is the first project that I used an automated raster to vector converter and it worked surprisingly well on the ECG lines.

I sliced the image in Prusaslicer and printed on a Prusa i3 MK3s+ at 0.3 mm layer height in black and white Hatchbox brand PLA.

The print came out well and I affixed it to the call room door:

My chair was happy with the result.

Anesthesia Equipment

RIC Lines – Very Large Bore Peripheral Intravenous Access

Rapid Infusion Catheters, or RIC Lines, are a product line of large bore peripheral IV catheters designed to be placed easily and rapidly in hemorrhaging patients. The catheters come in 2 sizes: 7 Fr (13.3 Ga) and 8.5 Fr (11.8 Ga). By using a 20 Ga IV to upsize to the RIC Line via seldinger technique, one is able to easily place a large bore RIC Line catheter into a medium sized vein which could otherwise be very challenging.

Skip to the bottom of the page for a thorough video of RIC line placement steps and considerations.

A 14 Ga IV catheter compared to the massive 7 and 8.5 Fr RIC Lines.

The Kit contents (pictured below) include 3 items:
1. RIC Line catheter with integrated skin dilator.
2. Guidewire in a plastic sheath.
3. Skin scalpel.

In addition to these items you will need:
1. Existing in-situ 20 Ga IV catheter.
(Or)
A. Tourniquet.
B. Skin antiseptic.
C. New 20 Ga IV catheter to be placed.
2. IV infusion tubing

7 Fr RIC line kit package contents. The 8.5 Fr kit is the same but the hubs of the catheter and dilator are blue.

Placement is fairly straightforward. Use an in-situ 20 Ga IV catheter or place a new 20 Ga IV catheter to act as an introducer for the guidewire. Remove the 20 Ga catheter, make a small skin nick with the scapel and place the integrated RIC Line and dilator into the vein, followed by removal of the dilator and guidewire.

Major considerations of the procedure
1. If you are placing a new 20 Ga IV catheter, try to avoid “bloodless” style catheters as the diaphragm that prevents back-bleeding, can also impede advancement of the guidewire.
2. Since this if often a used as a trauma line, utilize the maximum cleanliness that you have time for. If the patient is hemodynamically unstable, a quick swipe of an alcohol pad is appropriate; however, if this is being placed for an elective case, sterile technique can be used. You will be touching the guidewire and catheter with your hands, so the increased cleanliness is appropriate if the extra time is clinically appropriate.
3. If the patient is conscious, anesthetize the skin with local anesthetic.
4. Since the kit feels similar to a central line, it can be tempting to make a large skin nick, but this will result in damaging the superficial upper extremity vein. Be mindful to make a small 2-3 mm, superficial skin nick.
5. Despite the large bore, you may get little to no bleed-back and you may not be able to draw off the catheter. This results from 2 issues: The catheter may occlude the vein enough to impede proximal flow and the catheter may be larger than the vein and as such will suction the walls of the vein when drawn back. This feature is compounded by patient hypovolemia.
6. Remove the dilator! The dilator has a leur-lock connector and will flow at least as well as a 20 Ga IV if left in place. If not removed, the stiff dilator can produce significant damage to the vein.

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3D Printing

3D Printed Repair: The Modern revival of the ancient Japanese art of Kintsugi

Kintsugi is the ancient Japanese art of repairing broken pottery with gold, silver, or platinum. The philosophy of Kintsugi celebrates the history of an object by highlighting its repair instead of disguising it. The repair not only makes the object functional again, but also beautiful through its uniqueness.

A bowl repaired with lacquer and gold in the Kintsugi fashion.

Although the art of Kintsugi still exists, a modern offshoot of this art is evolving as part of our everyday lives due to the increasing affordability of 3D printing. Due to differing properties of the polymers used for printing and inability to make perfect color/shape matching, it has led some modern makers to highlight their repairs with unique shapes and colors just as with Kintsugi. In an age where almost everything is standardized and disposable, modern 3D Kintsugi is a breath of fresh air that, in addition to breaking the cycle of consumerism, adds beauty to our lives with unique objects that cannot be purchased on Amazon.

The evolution of 3D printing as a reparative art is in its infancy and a community devoted to these designs has yet to evolve but one can find a number of examples of it in 3D printing communities such as Reddit’s Functional Prints. A few examples are listed below:

A pair of scissors with 3D Printed handle repair. (From Reddit user: badatchopsticks)
A 3D Printed replacement stand for this LED mirror. (By reddit user: aqa5)
A laptop charger repaired with 3D Printed part. (From reddit user cafeBreak24)

As far as my own creations in the medical and hospital space, most of my creative interventions are not reparative in nature but a few of my creations do fit the bill and can be found here:

Here, this McGrath laryngoscope battery, which costs $50, had a broken removal tab to allow removal of the battery but still had 2/3 of the battery left. This $0.05 repair allows the additional $33 of the battery to be used.
When the pharmacy changed from large to small vials of clindamycin, instead of reprinting my entire emergency drug tray component, I simply made an insert to allow for organized storage of the new smaller vials.
A simple 3D Printed replacement of this epidural pump screw clamp bushing in white TPU.
A 3D printed Knob that I made for the anesthesia office toaster oven.

It is my hope that 3D Kintsugi will continue to evolve as a modern functional art form, extending the longevity of our possessions and adding unique and beautiful elements to our lives.

3D Printing, Organization

Anesthesia to the rescue….. In a flash!

Due to an unfortunate workplace injury, my friend, colleague, and anesthesia intensivist, the great Pavan Sekhar, MD, needed to use a knee scooter for a few months. In order to better facilitate his job, I designed and 3D printed an organizer for his scooter to allow for better organization and delivery of drugs, procedural equipment, and caffeine.

Here is the design that I conceived of in CAD:

The model contains places for drug vials, syringes, a box of epinephrine, small misc items, and large misc items, as well as a central cup holder for convenient infusion of intensivist caffeine.

Due to Dr. Sekhar’s affinity of the Marvel and DC universes, plus the speed at which he zoomed around the ICU on his scooter, I added a flash emblem to encompasss these traits. I sliced the flash emblem in PrusaSlicer to be used on a Prusa i3 MKS multi-material extruder setup to allow for multicolor printing without intervention.

The Prusa MMU2 utilizes a filament manifold to allow for multicolor 3D Printing.

I printed the box component at 0.3 mm height in PETG for strength and the flash emblem at 0.2 mm layer height in PLA for detail. Here is the final product:

Dr. Sekhar was happy with the final product and it will hopefully improve his organization and provide him with a few extra seconds during emergencies when seconds count!

3D Printing, Organization

A quick 3D print for pharmacy safety

Recently our hospital standardized a number of the adult vasopressor infusions. Our usual 10mg/250mL phenylephrine bags for infusion were eliminated and replaced by 20mg/250mL bags. Since phenylephrine is our primary vasopressor infusion for most anesthetics, our pharmacy drug trays include both a premixed bag of phenylephrine and a backup 10mg/1mL vial to mix into a 250mL saline bag if that initial bag is depleted. Pictured here is the backup concentrated phenylephrine 10mg/1mL vial in the drug tray:

For the transition to the more concentrated phenylephrine bags, the pharmacy now needed to supply 20 mg of concentrated phenylephrine in order to make backup phenylephrine bags. The two options were to include a larger phenylephrine vial (the next size up being 50mg/5mL) or adding an additional 10mg/1mL vial to the tray for a total of 2x 10mg/1mL vials. When the department was presented with the first option, many attendings were strongly against the 50mg vials since then worried that the less experienced residents may make a life threatening error with such a large, concentrated dose of phenylephrine. As for the second option, the pharmacy was against having 2 vials in the tray as there was no spot for the second vial and the pharmacists were worried about having a “free floating” vasopressor vial in the tray, especially an vial type which is shared by many other drugs. Replacing the blue tray foam inserts was not an immediate option as they had just been replaced a couple months prior and are prohibitively expensive to replace.

In order to expand the single phenylephrine vial spot into one big enough for 2 vials, I conceived of, designed, and 3D printed a quick and simple solution:

The cylindrical portion would slide easily into the vial spot and the rectangular portion would hold 2 horizontal vials. I printed the model in 2 parts to maximize speed and negate the need for 3D printed supports. The final part would be pressed together with a dab of glue. Between 3 Printers, I was able to complete the project overnight so that the pharmacy could implement the project immediately.

The pharmacy was satisfied with the solution and impressed with the speed at which the project was completed. This project, which used approximately $5 worth of materials, is an excellent example of how in-house 3D Design and Fused Deposition Modeling can be used to create immediate and useful solutions to problems that would otherwise require compromise or take months to implement.

3D Printing, Organization

Small Medication Ampoule Organization

On more than one occation, when in a hurry, I have broken a few glass medication ampules. The all glass amps can be broken fairly easy when opening a storage or omnicell drawer as they tend to roll around.

In order to reduce the risk of broken glass and save the expense of wasted medications, I designed a couple varieties of organizers to prevent these issues in the future.

Here are the CAD designs that I conceived of:

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The first desgn was intended mostly for lidocaine amps in the anesthesia carts while the second was intended for displaying the amps more clearly in the omnicell.

Here are the 3D Prints and their implementations:

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I have yet to break an amp since implementing this organizers. One of the pharmacy techs commented that they thought the main pharmacy had purchased these from a supplier rather than a 3D printed item that I had made on the fly.