Motion capture measures variability in laryngoscopic movement during endotracheal intubation: a preliminary report

Success rates with emergent endotracheal intubation (ETI) improve with increasing provider experience. Few objective metrics exist to quantify differences in ETI technique between providers of various skill levels. We tested the feasibility of using motion capture videography to quantify variability in the motions of the left hand and the laryngoscope in providers with various experience.

Three providers with varying levels of experience [attending physician (experienced), emergency medicine resident (intermediate), and postdoctoral student with no previous ETI experience (novice)] each performed ETI 4 times on a mannequin. Vicon, a 16-camera system, tracked the 3-dimensional orientation and movement of markers on the providers, handle of the laryngoscope, and mannequin. Attempt duration, path length of the left hand, and the inclination of the plane of the laryngoscope handle (mean square angular deviation from vertical) were calculated for each laryngoscopy attempt. We compared interattempt and interprovider variability of each measure.

All ETI attempts were successful. Mean (SD) duration of laryngoscopy attempts differed between experienced [5.50 (0.68) seconds], intermediate [6.32 (1.13) seconds], and novice [12.38 (1.06) seconds] providers (P = 0.021). Mean path length of the left hand did not differ between providers (P = 0.37). Variability of the plane of the laryngoscope differed between providers: 8.3 (experienced), 28.7 (intermediate), and 54.5 (novice) degrees squared.

Motion analysis can detect interprovider differences in hand and laryngoscope movements during ETI, which may be related to provider experience. This technology has potential to objectively measure training and skill in ETI.