Purpose: Thoracoscopic esophageal atresia/tracheoesophageal fistula (EA/TEF) repair is an uncommon operation requiring advanced minimally invasive skills. Unfortunately, currently available simulation models for EA/TEF repair are low fidelity models, focusing on intracorporeal suturing of synthetic tubes. We sought to create a high fidelity, anatomically correct real tissue simulation model, including relevant thoracic landmarks. The purposes of this study were 1) proof of concept and 2) to evaluate the content validity of a high fidelity thoracoscopic EA/TEF simulator as an educational tool.
Methods: Simulation experts (architecture, engineering, education, surgery and emergency medicine backgrounds) collaborated in model design. Literature review and chest x-rays of neonates were used to create a to-scale neonatal rib cage, using 3-D engineering software. A neonatal rib cage (image 1) was created with a rapid prototype 3-D printer. The simulator was completed by explanted fetal bovine tissue, surgically modified to represent appropriate congenital anomalies, and covered with simulated skin (image 2). Nine pediatric surgery fellows and two faculty members (n = 11) performed the simulated thoracoscopic EA/TEF repair. Participants completed a self-report, six-domain, 24-item instrument consisting of 5-point rating scales, ranging from 0 (Don't know) to 4 (Highly realistic, no changes needed). An additional 4-point item was used to identify participants' global opinion of the simulator. Construct validity relevant to test content was evaluated by examining the ratings using the many-Facet Rasch model.
Results: Analysis indicated no differences when comparing faculty (Observed Average (OA) = 3.5/4.0) to fellow (OA=3.3) ratings, p = .71. In descending order, observed averages of the domains were 3.9 (Relevance), 3.75 (Value), 3.5 (Physical attributes), 3.5 (Realism of materials), 3.4 (Realism of experience) and 3.32 (Ability to perform task). The highest observed averages were Physical attributes-Chest circumference (OA = 4.0), Physical attributes-Chest depth (OA = 4.0), Value of simulator as training tool (OA = 4.0), while the lowest ratings were Physical attributes-Landmark visualization, scapula (OA = 2.9), Realism of materials-skin (OA = 2.9), and Ability to repair esophageal atresia (OA = 2.7). The observed average of Global opinion rating was 3.0/4.0, indicating the simulator can be considered for teaching thoracoscopic EA/TEF repair, but could be improved slightly.
Conclusions: Collaboration across several divergent fields enhanced the creation of a thoracic space relevant to neonatal procedures. Inexpensive fetal bovine tissue and synthetic skin completed the high-fidelity model. Fellow and faculty ratings indicated the simulator was relevant to clinical practice and valuable as a learning tool, with minor modifications. Comments were consistent with the high physical attribute ratings. Further evidence relevant to internal structure, response processes, and relationship to other variables is required before implementation of this high fidelity EA/TEF model as an educational tool.