Comparisons of two diaphragm ultrasound-teaching programs: a multicenter randomized controlled educational study

Abstract

Background: This study aims to ascertain whether (1) an educational program is sufficient to achieve adequate Diaphragm Ultrasound (DUS) assessments on healthy volunteers and (2) combining a video tutorial with a practical session is more effective in making learners capable to obtain accurate DUS measurements, as opposed to sole video tutorial.

Results: We enrolledstep 1: 172 volunteers naïve to ultrasound. After watching a video tutorial, a questionnaire was administered and considered to be passed when at least 70% of the questions were correctly answered. Course participants who passed the theoretical test were randomized to either intervention or control group. Learners randomized to the interventional group underwent to a practical training, tutored by an expert, before accessing DUS examination. Participants randomized to the control group directly accessed DUS examination, without any practical training. DUS measurements by learners and tutors were recorded and checked for accuracy, according to predefined criteria. Detection of both acoustic windows and accurate DUS assessment was achieved by 83.7% learners of the intervention group while 3.5% only among controls (p < 0.0001). The subcostal view of the diaphragm was correctly identified by 92% and 65% learners in the intervention and control groups, respectively (p < 0.0001) while the apposition zone by 86% and 71% learners, respectively (p = 0.026). An accurate diaphragm displacement (DD) measurement was obtained by 91% and 45% learners in the intervention and control groups, respectively (p < 0.0001) while an accurate thickening fraction (TF) measurement by 99% and 21%, respectively (p < 0.0001). DD measurements by both groups of learners were significantly correlated with those assessed by expert tutors; however, a significant improvement of measurement accuracy was found in learners randomized to receive also the practical training, compared to controls.

Conclusions: A combined approach consisting of a theoretical module followed by a practical training is more effective in managing acoustic windows and performing accurate measurements when compared to an exclusively theoretical course. Trial registration prospectively registered on clinicaltrials.gov (Identifier: NCT03704129; release date 17th October 2018).

Keywords: Course; Critical care; Diaphragm imaging; Diaphragm ultrasound; Education; Intensive care unit; Learning; Training.

Conflict of interest statement

Dr. Navalesi’s research laboratory has received equipment and grants from Maquet Critical Care, Draeger and Intersurgical S.p.A. He also received honoraria/speaking fees from Maquet Critical Care, Orionpharma, Philips, Resmed, MSD and Novartis. Dr. Navalesi contributed to the development of the helmet Next, whose licence for patent belongs to Intersurgical S.P.A., and receives royalties for that invention. Dr. Longhini and Dr. Navalesi contributed to the development of a new device not discussed in the present study whose patent is in progress (European Patent Application Number EP20170199831). The remaining authors declared that they no competing interests.

Figures

Fig. 1

Number of learners reaching the study aims. From left to the right, the figure depicts the number of learners that: (1) correctly detected both acoustic windows and performed accurate measurements (first outcome); (2) correctly identified the subcostal view; (3) correctly identified the apposition zone; (4) accurately performed the DD measurement; and (5) accurately performed the TF measurement. White bars represent the intervention group while grey ones the control group. The dashed line represents the total number of learners randomized per group (n = 86)