A cricothyroidotomy training phantom, created using 3D printing and ballistics gel molding. Intended for practice in locating the cricothyroid membrane and creating an incision through it. See purchasing information and maintenance and assembly instructions below.
This model was developed at the Lynn & Arnold Irwin Advanced Perioperative Imaging Lab, Toronto General Hospital, University Health Network.
Fully assembled phantom.
To purchase this phantom, please email [email protected] and a representative will be in touch with you with more details.
A purchased phantom contains the following:
- APIL Cricothyroidotomy Phantom base
- 10 x gel overlays
- 10 x fully assembled insert rings
Store gel overlays in a bag or box when not in use to prevent tearing from excessive handling. Once an overlay is placed on a phantom and used (i.e. cut into), it can be replaced with another. If more gel overlays are desired, the gel can be remelted and cast to form new overlays by following the assembly instructions below.
A used insert ring can be replaced with another, or can be reused by rewrapping the ring with duct tape.
- base — cricothyroidotomy base.stl
- molding insert* — cricothyroidotomy molding insert.stl
- insert — cricothyroidotomy ring.stl
- intermediate mold part 1** — intermediate mold 1.stl
- intermediate mold part 2** — intermediate mold 2.stl
Files are available for download here.
* Print the molding insert with HTPLA or another heat resistant 3D printing filament. The other components can be printed with any kind of rigid plastic.
** A portion of these components were modified from NIOSH National Personal Protective Technology Laboratory (NPPTL)’s ISO Digital Headforms (specifically the medium size): https://www.cdc.gov/niosh/npptl/topics/respirators/headforms/default.html
- Duct tape
- 4 M3 screws
- High temperature PLA, or another 3D printing filament with heat-resistant properties
- Optional other filament (PLA recommended)
- Ballistics gel (https://www.clearballistics.com/shop/20-ballistic-gelatin-nato-block-16x6x6/, https://humimic.com/product/gelatin-4-medical-gel-by-the-pound/)
- Graphite powder
- Smooth-On’s Dragon Skin 30A Silicone Rubber, or another silicone of similar hardness (https://www.smooth-on.com/products/dragon-skin-30/)
- 3D printer
- Degassing chamber
- Crock pot, or another method of melting the ballistics gel
CAUTION: Use appropriate heat-proof gloves when working with liquefied ballistic gel and/or heat gun.
CAUTION: Work only in a very well ventilated area. A fumehood is highly recommended.
- Print out the printed components, using a heat-resistant filament for the molding insert, and any kind of rigid plastic for the other components.
- Use four M3 screws to attach the two intermediate mold components together. Seal off the seams with clay or hot glue. Prepare, degas, and pour roughly 750mL of Smooth-On’s Dragon Skin 30A Silicone Rubber (or another silicone of similar hardness) into the intermediate mold. Once cured, remove the silicone mold from the intermediate mold.
- Seal off the molding insert to prevent ballistics gel from entering the inside of the insert. Here this was done with a taped insert and silicone.
Molding insert, sealed off with tape and silicone.
- Melt 80 g of ballistics gel (here, a roughly 2:1 mixture of 20% ballistics gel and Humimic Medical Ballistics Gel #4 was used) in a crockpot at 105C - 115C (approx. 225F - 240F).
- Stir graphite powder into liquefied gel until saturated and uniformly distributed.
- Pour roughly 75 g of ballistics gel into the mold then insert the molding insert. The top of the insert should be just above the top of the mold.
Gel molding process. The sides of the mold have been clamped here to ensure the mold retains its shape.
- Wait until gel cools (~45 min) then remove the insert. Cut off the overlapping edges and peel the gel off the insert carefully. Ensure there are no holes around the area of incision.
Left: post-molding results. Right: gel peeled off of molding insert.
- Wrap the insert twice with duct tape and place inside the base, aligning the insert’s hole with the incision site. Place the gel onto the cricothyroidotomy base.
Assembled phantom.
