Real-Time Fiber-Optic Intubation Simulator With Force Feedback

Fiber-optic intubation is an emergency procedure that can be performed to intubate a patient when the patient has serious difficulty in breathing normally. The existing simulators for fiber-optic intubation procedure provide haptic feedback to the user when there is a contact with the vocal cord section, but they do not capture the grazing effect of the endoscope along the inner walls of the airway. The grazing on the inner walls of the airway, if not well controlled, could lead to unnecessary trauma for the patient. Hence, there is a need to provide this force feedback in a fiber-optic intubation simulator. We have built a fiber-optic intubation simulator with force feedback. This system is composed of a software simulation coupled with a physics-based simulation that enhances the visual experience. The software simulation is connected to a haptic feedback device. The device provides force feedback when contact is made with any section of the airway. The force feedback varies based on the position of contact and intensity of contact. We use a proportional and derivative (PD) controller to obtain force feedback at the vocal cord section and a variable magnetic field to capture the grazing effect of the endoscope along the inner walls of the airway. The movements of the endoscope are captured using rotary encoders (that read the insertion and the tip bend) and a compass module (that reads the twist angle of the endoscope along the long axis). These movements are used to navigate the virtual airway using a virtual endoscope. When collisions are encountered, the physics library evaluates the position of contact and the force with which contact is made. Force feedback is generated due to the interaction of the solenoids with the permanent magnets at the tip of the endoscope. This information helps the software to actu- ate the right combination of solenoids. The simulator will help to train all aspects of fiber-optic intubation, namely 1) developing the necessary psych- motor skills to successfully navigate the airway with minimal or no damage to the airway or vocal cords; and 2) cognitive skills to perform the procedure fast and effectively.