Feasibility study of a new operating table concept: an analysis of stress distribution using FEM

Operating tables have an essential role in the surgical theater because they contribute to the patient’s safety and comfort during surgery. Since the beginning of the development of medical devices for surgery, functionality and design of surgical tables have improved, with the constant goal of accommodating and conforming to the patient’s body in order to avoid the manifestation of pressure, friction and shear forces. However, many everyday used and gold-standard surgical tables display a lack of customization, most of all when patients' morphologies and weights are different from the typical standard body proportions. A range of $9.1 billion to $11 billion is spent in the United States each year for treating the pressure injuries caused by this inefficiency. In this thesis, a new concept operating table is suggested to offer a reduction of the negative effects of poor patient positioning during surgery. The new table aims to better support the patient’s body, reduce pressure points and maintain proper positioning by providing an innovative platform structure. The use of finite element analysis (FEM) and computer-aided design (CAD) simulation have a crucial role in demonstrating the efficacy of the suggested new concept. The first step in the study is to validate a CAD model that accounts for the effect of the human body's weight on a simplified operating table mattress made of various materials. Weight forces must be applied to the simplified model table in order to obtain pressure values for every selected material. The different pressure distributions are then compared to the existing literature and the one that closely mimics the mechanical characteristics of the standard operating table is chosen. The second phase of modeling can start as soon as the validation is completed. The study chooses four common surgical positions and replicates them with a CAD dummy to demonstrate whether the new concept operating table reduces interface pressure. The portion of the body that should be exposed to the table is covered with squared silicon pads, the main element of the table. A FEM analysis is made for every surgical position with the same weight as in the first part and the obtained values of pressure, stress and displacement are then compared to the ones in literature. The feasibility study’s result provides evidence that the new concept operating table is successful in reducing interface pressure underneath the patient’s body during the long surgical times. In the supine position, a statistically significant reduction in stress was observed on the scapular surface by 25%, on the sacrum by 32%, and on the heels by 35%. The new design is stable, adaptable, and capable of supporting the patient's body in the appropriate position and preventing pressure injuries. The study supports that the proposed model can help in lessening surgical time and improving patient outcomes, among other advantages. The study suggests a foundation for future research and development in this area, with the ultimate goal of enhancing patient safety and surgical outcomes.