Feasibility and Acceptability of a Structured Curriculum in Teaching Procedural and Basic Diagnostic Ultrasound Skills to Internal Medicine Residents Open Access

Point-of-care (POC) ultrasound has emerged as a powerful tool for physical diagnosis.1 Clinicians have demonstrated the ability to obtain basic images, answer focused questions, and integrate their findings into patient management.2 Clinical uses include evaluation of central venous pressure,3–6 cardiac contractility,7,8 pericardial effusions,9 pleural effusions,10,11 pulmonary edema,12 pneumothoraces,13 and ascites.14,15 

Ultrasound skills are of increasingly wide interest to clinicians, and a number of medical schools have introduced ultrasound into their curriculum.16,17 Our survey showed that many internal medicine program directors believe these skills are important for internists,18 and a previous survey showed that medical students and internal medicine residents strongly desire this training.19 

We describe a 30-hour introductory ultrasound course designed to teach basic skills (physics, how to manipulate the ultrasound machine and probe), ultrasound-guided procedures (central venous catheters, arterial lines, paracentesis, and thoracentesis), and focused diagnostic ultrasound of the great vessels, heart, pericardial space, pleura, pleural space, lung, and abdominal structures.

Thirty first-year internal medicine interns and 2 internal medicine-dermatology interns at the University of Minnesota participated in a mandatory ultrasound course during intern orientation in June 2012. The course was taught in the Simulation Center (SimPORTAL), which also provided a grant to cover the cost of the simulators, volunteers, and materials. The cost of disposable materials such as procedure kits was $17,000, and $9,000 was spent to purchase additional reusable materials for the course.

The 5-day course used a combination of web-based, didactic, and hands-on ultrasound training. Content was selected through consensus by local experts in emergency and critical care ultrasound and from the results of a recent survey of internal medicine program directors and faculty.18 The course was taught by a faculty coordinator (D.J.S.), faculty in internal and critical care medicine, and chief residents. All instructors had completed at least 30 hours of training in POC ultrasound, and several had significant experience. Most ultrasonography procedures were carried out with NanoMaxx ultrasound machines (SonoSite Inc, Bothell, WA).

Learners completed 1 of 2 equivalent 25-question tests (Test A or B) covering ultrasound physics, image interpretation, and integration of ultrasound findings into clinical management. Prior to each session, learners reviewed web-based modules and journal articles and took a quiz. Web-based content is provided as online supplemental material.

Course days 1 to 4 began with a review of the previous night's material and quizzes and was followed by practical sessions. These sessions included scanning models, procedural simulators, and ultrasound simulators. Additional topics in quality assurance and quality improvement were presented. Details of daily course content are provided in the B O X.

On day 5, learners' knowledge and skills were assessed. Each learner completed either Test A or B (the version they had not completed as the pretest), performed 4 procedures on simulators by using procedural checklists, and performed a 39-point diagnostic scan on a volunteer. The procedural checklist (an example of which is provided as online supplemental material) was adapted with permission from the University of Miami. The diagnostic scanning checklist was developed by consensus of the authors of the most important skills for novice sonographers. Learners also participated in 3 practical scenarios (provided as online supplemental material) that incorporated image acquisition, interpretation, and integration into the management of a simulated patient. Details of the examination stations are provided in B O X 2.

Learners were asked to complete pre and postsurveys regarding their experiences and attitudes about POC ultrasonography. Content included the presence and quantity of prior ultrasound experience (table 1), confidence in performing POC ultrasound, and attitude regarding its use.

Scores for students who took Test A and Test B as a pretest were compared using a 2-sample t test to compare scores on the 2 tests. Paired 2-tailed t test was used to compare scores for students on the pretest and posttests.

Twenty-nine of 32 learners completed precourse surveys, and 25 of 32 learners completed postcourse surveys. A total of 90% of respondents (26 of 29) had no prior ultrasound experience outside of medical school; 2 reported 1 to 2 years of experience; and 1 reported 3 to 5 years of experience. Eighty-six percent (n  =  25) reported less than 5 hours of ultrasound training. All 32 learners completed pretests and posttests. A significant increase in performance was seen between the pretest and posttest, as shown in table 2.

In the 3 practical scenarios, learners scored an average of 9.2 ± 0.9 of 10 points. They averaged 3.3 ± 0.4 of 3.5 points possible for image acquisition, 3.4 ± 0.7 of 4 points for image interpretation, and 2.5 ± 0.1 of 2.5 points for integration into clinical management; each participant was evaluated in real time by an instructor completing a checklist.

All learners were evaluated on their ability to demonstrate technique and acquire pertinent images for the skills (the evaluation tool is provided as online supplemental material). Passing was determined by a participant's ability to acquire images without “significant hands-on assistance,” rated by consensus of 2 instructors who evaluated the learners (D.J.S. and A.P.J.O.). This was achieved by 27 of the participants. Two learners received a 1-hour review session to correct specific deficiencies in techniques, 2 struggled with a single skill (eg, pulmonary) and were asked to repeat a portion of the course, and 1 was asked to repeat the entire course.

Learners completed a retrospective pre-post course survey in which they were asked whether they were able to perform important ultrasound skills, on a scale of 1 to 5. All perceived improvement in their ability to acquire images (1.77–4.04), recognize pertinent pathology (1.92–3.88), and integrate findings into management (2.00–3.84; all P < .001). For each individual diagnostic application, learners reported improvement in their abilities to obtain and interpret images and integrate findings into management (all P < .001). Participants believed ultrasound would be useful in residency and their future practice (4.6) and a practical tool for physical diagnosis (4.5).

Learners rated the effectiveness of the teaching methods highly and were evenly divided as to whether live lectures would be preferable to online videos. Details of the course evaluation can be found in table 4.

To our knowledge, this paper describes the first formal program-wide POC ultrasound course teaching a large number of applications to internal medicine residents. We incorporated and tested skills needed to effectively use ultrasound, including indications for use, image acquisition and interpretation, and integration into diagnostic management.20 The content, breadth, and time commitment is similar to the course required by the American College of Emergency Physicians21 and World Interactive Network Focused on Critical Ultrasound22 UltraSound Critical Management Certification, 2 well-regarded pathways leading to certificates in POC ultrasound. For both courses, mandatory didactic and hands-on coursework is followed by a period of apprenticeship and image review and sometimes further testing in order to receive a certificate.

Our program views this intervention as the initial building block upon which further ultrasound and procedural training will be built over the course of residency. We view the successful completion of this course as advancing learners at a level 2 on a 5-level framework developed by the Alliance of Academic Internal Medicine, with level 4 defining the achievement of skills learners should attain at the end of formal training.23 Level 2 denoted readiness to perform these skills with full supervision. Additional opportunities to perform procedures on patients; additional coursework and testing; and supervised diagnostic scanning during critical care, hospital medicine, and emergency department rotations will allow learners to progress toward independent practice.

In an era of dwindling resources for medical education, this course used a significant portion of freely available online content, which helped reduce the need for faculty time to focus on hands-on skills. Faculty time commitment ranged from 3 to 30 hours, with program-supported core faculty and chief resident physicians representing the more intensive commitments. The simulators represent a fixed cost. The department and residency are planning the course again in 2013.

Several students struggled on the final scanning test and required remediation to advance to level 2. Variability in instruction likely contributed to 2 of the students failing just 1 of the skills. Two interns failed due to haptic aspects such as weak probe control; future renditions of the course will focus on this aspect earlier and more deliberately.

Our POC ultrasound course was effective in teaching skills that prepared interns to use this technology under supervision. Further work is needed to determine the best methods to teach internal medicine trainees the use of POC ultrasound over the course of residency, including a focus on skill retention, building higher-level skills, and advancement of learners to independent practice.