Stomach Material Choice
The final decision for the stomach material was to use a synthetic organ material produced by SynDaver Labs.
The geometry of these products is modeled from a combination of CT and MRI images from actual patients, ensuring geometric accuracy for the placement of nasojejunal feeding tubes. According to the SynDaver website, the synthetic organs are also compatible with surgical equipment, such as endoscopes. This indicates that the tissues will also be compatible with nasojejunal feeding tubes. The details of the mechanical properties of these organs is proprietary information held by SynDaver.
Mucus Material Choice
The final decision for the mucus material was to use a ID Glide personal lubricant.
The viscosity of ID Glide lubricant is 751 cP at 25 degrees Celcius and a shear rate of
38.4 s-1. This viscosity falls within the acceptable range of 660-840 cP at 38.4 s-1 in order to mimic the viscosity of gastric mucus. Additionally, this product is proven to be safe for human use, both externally and internally. Therefore, user interaction with the product will not cause harm. ID Glide also fulfills the durability requirement of 24 uses, as it will remain in the model for multiple uses, and the user may reapply as needed. Furthermore, this lubricant is water soluble; once validation tests have been completed, the process of washing the model will be simple. 4.4 ounces of ID Glide costs $11.69, which is affordable within a $10,000 budget for the GI system model. Lastly, the ID Glide is easily transported.
Containment System
Our design for the containment system for the model is a Plexiglas Acrylic box, with rubber sheets made of silicon for suspension of the organ tract.
Plexiglas is an inexpensive plastic material with a short lead time (48 hours). It can be easily cut to appropriate sizes and dimensions. Additionally, it is transparent allowing for easy viewing of/access to the synthetic GI tract.
Silicone rubber sheets allow for an appropriate amount of movement with changes in the orientation of the containment system and is of a similar thickness to the peritoneum. Additionally the use of large sheets that envelop the synthetic tract simulate the in vivo attachment of the mesentery to abdominal organs.
Design Choice
After much deliberation and research, our group decided on a final design for the model. We have included the components below, and some of the detail behind the choices.
Final (Partially) Assembled Design
We have included an image of a partially constructed prototype for the model. This model does not have the exact dimentisons and properties that we had laid out as a project scope due to limitations in time for their assembly.
However, we are proud of this as a good proof of concept for the final design!
