Detecting cervical esophagus with ultrasound on healthy voluntaries: learning curve

The objective of this study was to determine the learning curve of tracheal-esophageal ultrasound by prehospital medical and paramedical staff.

A single-center prospective study was carried out at a French EMS (SAMU 92). Volunteer participants first received a short theoretical training through e-learning, followed by two separate hands-on workshops on healthy volunteers, spaced one to two months apart. Learners were timed to obtain the tracheal-esophageal ultrasound target image 10 consecutive times. The first workshop was intended to perform a learning curve, and the second was to assess unlearning. The secondary objectives were to compare performance by profession and by previous ultrasound experience.

We included 32 participants with a mean age of 38 (± 10) years, consisting of 56% men. During the first workshop, the target image acquisition time was 20.4 [IQR: 10.6;41] seconds on the first try and 5.02 [3.72;7.5] seconds on the 10th (p < 0.0001). The image acquisition time during the second workshop was shorter compared to the first one (p = 0.016). In subgroup analyses, we found no significant difference between physicians and nurses (p = 0.055 at the first workshop and p = 0.164 at the second) or according to previous ultrasound experience (p = 0.054 at the first workshop and p = 0.176), counter to multivariate analysis (p = 0.02).

A short web-based learning completed by a hands-on workshop made it possible to obtain the ultrasound image in less than 10 s, regardless of the profession or previous experience in ultrasound.