Kinematic and kinetic evaluation of videolaryngoscopes through motion analysis and robotics

Airway management is a critical procedure in anesthesiology and emergency care, where opening the patient’s airway often requires endotracheal intubation. In recent years, videolaryngoscopes have been increasingly adopted to facilitate this maneuver and improve visualization of the airway. However, endotracheal intubation performed using videolaryngoscopes can still involve significant risks for the patient, including dental trauma and oropharyngeal tissue injuries. Literature indicates that these complications are often caused by excessive loads applied during the maneuver. Current methods in measuring forces and moments over the entire blade of the device provide only partial information about the loads, as they allow the analysis of load magnitudes but not their directions. The aim of this thesis is to perform an experimental evaluation of the endotracheal intubation maneuver from a kinematic and kinetic perspective, combining motion capture and collaborative robotics. Another goal is to analyze innovative devices such as the Medsniper, which has not yet been investigated in the literature, and to compare it with traditional videolaryngoscopes. Three videolaryngoscopes (Airtraq, Besdata, and Medsniper) were tested on a mannequin simulating two experimental conditions (with and without a rigid cervical collar). The proposed experimental approach is based on two main phases: data acquisition and robotic replication. In the first phase, ten clinical operators with different levels of experience performed the intubation maneuver on a mannequin equipped with force sensors at the teeth. Data were recorded using a motion capture system with 12 infrared cameras and 1 video camera capable of detecting markers placed on the mannequin and on the videolaryngoscopes. Each operator performed four repetitions for each device and experimental condition. The trajectories were reconstructed using Vicon Nexus software, and the data were processed to be used in the second phase of the study. This consisted of replicating the maneuvers with a robotic arm, the Doosan H2515, instrumented with a load cell that allowed the measurement of forces and moments in the three local directions of each device. The results showed consistent differences between the devices. Medsniper suggested an improved performance, with intubation times comparable with traditional devices, but transmitting lower forces and moments, while also reducing the required range of motion, indicating greater stability and repeatability of the maneuver. Besdata, on the other hand, showed the highest variability and operational complexity, particularly among less experienced operators, while Airtraq presented an intermediate behavior. In addition, the effect of the rigid cervical collar did not produce significant changes in the distributions but, in some cases, reduced data variability. In conclusion, this thesis demonstrates that the combination of motion capture and robotics enables a complete and reproducible biomechanical assessment of the endotracheal intubation maneuver. Furthermore, the Medsniper, compared to traditional devices, has shown strong clinical potential to improve patient safety and opens new perspectives for the development of innovative technologies for airway management.