Background: The need for surgeons to become proficient in performing and interpreting ultrasound examinations has been well recognized in recent years, but providing standardized training remains a significant challenge. The UltraSim (MedSim, Ft. Lauderdale, Fla) ultrasound simulator is a modified ultrasound machine that stores patient data in three-dimensional images. By scanning on the UltraSim mannequin, the student can reconstruct these images in real-time, eliminating the need for finding normal and abnormal models, while providing an objective method of both teaching and testing. The objective of this study was to compare the posttest results between residents trained on a real-time ultrasound simulator versus those trained in a traditional hands-on patient format. We hypothesized that both methods of teaching would yield similar results as judged by performance on the interpretive portion of a standardized posttest. It is designed as a prospective, cohort study from two university trauma centers involving residents at the beginning of their first or second postgraduate year of training. The main outcome measure was performance on a standardized posttest, which included interpretation of ultrasound cases recorded on videotape.
Methods: Students first took a written pretest to evaluate their baseline knowledge of ultrasound physics as well as their ability to interpret basic ultrasound images. The didactic portion of the course used the same teaching materials for all residents and included lectures on ultrasound physics, ultrasound use in trauma/critical care, and a series of instructional videos. This didactic session was followed by 1 hour for each student of hands-on training on medical models/medical patients (group I) or by training on the ultrasound simulator (group II). The pretest was repeated at the completion of the course (posttest). Data were stratified by postgraduate year, i.e., PG1 or PG2.
Results: A total of 74 residents were trained and tested in this study (PG1 = 48, PG2 = 26). All residents showed significant improvement in their pretest and posttest scores (p = 0.00) in both their knowledge of ultrasound physics and in their interpretation of ultrasound images. Importantly, we could not demonstrate any significant difference between groups trained on models/patients (group I) versus those trained on the simulator (group II) when comparing their posttest interpretation of ultrasound images presented on videotapes (PG1, group I mean score 6.9 ± 1.4 vs. PG1, group II mean score 6.5 ± 1.6, p = 0.32; PG2, group I mean score 7.7 ± 1.4 vs. PG2, group II mean score 7.9 ± 1.2, p = 0.70).
Conclusion: The use of a simulator is a convenient and objective method of introducing ultrasound to surgery residents and compares favorably with the experience gained with traditional hands-on patient models.
The use of ultrasound by surgeons has received considerable attention in recent years. Focused ultrasound examinations performed and interpreted by the surgeon have become increasingly important in trauma, vascular, breast, and endocrine surgical practice, as well as in both open and laparoscopic surgical procedures. However, as recognized by the American College of Surgeon’s Committee on Emerging Surgical Technology and Education, these clinical applications of ultrasound require unique knowledge and skill. 1 The surgeon must be able not only to interpret normal and abnormal ultrasound images, but must also be able to acquire high-quality images. This latter skill requires a thorough knowledge of applied physics, an understanding of the mechanics of the ultrasound machine itself, an appreciation of anatomy, and a certain degree of hand-eye coordination. However, as Rozycki and others have consistently demonstrated with the Focused Assessment for the Sonographic examination of the Trauma patient (FAST), an experienced surgeon sonographer is capable of performing and interpreting an examination for pericardial and peritoneal fluid with a specificity approaching 100%. 2–4 Still, providing the needed education and training for surgical residents in this important new skill remains a formidable challenge to surgical educators.
Perhaps the most popular standardized course for surgeons and emergency physicians in the United States and in several other countries world-wide is the Advanced Trauma Life Support (ATLS) course offered by the American College of Surgeons. 5 The ATLS course includes standardized lectures given by qualified instructors using the same teaching materials at every course. Both the teaching and testing hands-on sessions are also standardized as much as possible, including preselected patient scenarios and moulaged patients. The Ultrasound National Faculty of the American College of Surgeons is in the process of designing ultrasound courses based on the ATLS model. However, finding “standardized” patient models with identical pathologic conditions for each course is impossible. The use of an ultrasound simulator in these courses provides a means of introducing selected pathologic images as well as a method of conducting a standardized test. Herein, we report our preliminary experience with use of the UltraSim medical simulator to introduce ultrasound to surgery residents. The purpose of this study was to compare the results on a posttest between students who gained their practical skills by using human models versus those who learned on a simulator. We hypothesized that the students who used the simulator would perform as well on the interpretative portion of the posttest as those who learned in the more traditional manner.