Abstract:

This paper presents a two phase approach in the development of a full scale 3D printed model of the human anatomy for supporting simulation based learning experiences (SBLEs) that are being used to train nursing students in the College of Nursing (CoN) at The University of Alabama in Huntsville. SBLEs are structured activities that represent actual or potential situations in education and practice. These activities allow nursing students to develop or enhance their knowledge, skills, and attitudes and to analyze and respond to realistic situations in a simulated environment. In Phase I 3D printed models of the spine, rib cage and pelvis served as the framework. 3D printed models were also printed of the lungs, trachea, heart, brachiocephalic trunk and the left subclavian trunk and placed inside the rib cage. 3D printed models of the cervical spine segment, clavicles, scapulas and sternum were then added. The STL (stereolithography) files were from CT (computed tomography) scans and were obtained from Embodi3D, Thingiverse and the National Institutes of Health.

Considerable modifications were made to most of the STL files for:
1) scaling the organs,
2) strengthening the walls of the organs such as the heart and
3) adding more PLA (polylatic acid) filament to weak points such as the ribs.

The 3D printed models were printed using PLA on a Makerbot+. Specialized fixtures were 3D printed to hold the arteries rising from the aorta, the celiac trunk, renal arteries and the superior and inferior mesenteric arteries. Various diameters of silicone rubber o-ring cord were used to simulate the spinal cord, aorta and the arteries rising from the heart and aorta. In Phase II the following additional 3D printed models were added: liver, stomach, gallbladder, spleen, pancreas and bladder. The majority of the arteries were added in Phase II. A literature review was conducted to obtain the diameters of the arteries. The diameters of the o–ring cord were then matched with the literature. All the arteries rising from the aorta and celiac trunk were included in the model.

In total:
1) twenty-eight arteries rising from the aorta, aortic arch, brachiocephalic trunk and the left subclavian trunk,
2) the esophagus and
3) the duodenum were included in the model.

Various diameter sleeves were designed using CAD (computer assisted design) and 3D printed. O-ring cords were then super glued into the sleeves and the sleeves fused to the organs. An attempt to add the next level of artery detail was unsuccessful due to the lack of space to insert these arteries and the non flexibility of the organs. A 3D printed model was also printed of the intestines. However, due to rigidity the 3D printed model could not be correctly positioned. The 3D printed model of the body is currently being integrated into selected SBLEs in the College of Nursing for training students on human anatomy and physiology. During the implementation of the 3D printed model into the SBLEs the faculty in the CoN requested a feature to remove the organs during the training sessions. As a result, specific trainers are being developed that include more arteries and space between the organs. Included in this paper are descriptions of the organs and the 3D printed models of the organs, integration of the organs into the model, difficulties in assembly and conclusions.

Keywords:

3D printed models, organs, arteries, simulation based experiences.