Eye tracking to understand performance in point-of-care lung ultrasound: Insights from nurse practitioners training

ABSTRACT: Teaching and assessing lung point-of-care ultrasound (POCUS) requires attention to both image acquisition and interpretation. Eye tracking offers an objective approach to examining visual attention during scanning, yet its use in hands-on ultrasound training remains limited. This convergent mixed-methods study used eye tracking to characterize visual attention and performance during lung POCUS training. Thirty-five nurse practitioners completed simulation-based lung POCUS training while wearing eye-tracking glasses; three experts completed the same protocol for comparison. Performance was assessed using image acquisition time, fixation metrics, site-level performance scores, and the Objective Structured Assessment of Ultrasound Skills (OSAUS). Mixed-effects models examined learner and contextual factors, including patient, instructor, and equipment characteristics, and their associations with post-training confidence and interpretation accuracy. Experts demonstrated faster image acquisition and more focused gaze patterns than learners. Performance varied across lung zones, with lateral and basal regions presenting the greatest challenges. Lower patient adiposity facilitated scanning, whereas baseline knowledge and confidence were not associated with performance. Higher gaze-based performance was associated with greater post-training confidence, and OSAUS scores were associated with interpretation accuracy. Instructors reported that video-based review was valuable but emphasized that gaze data alone were insufficient without contextual views of probe handling. When used as an analytical approach, eye tracking provides complementary insight into scanning performance and may help inform targeted, site-specific lung POCUS training strategies.