Effect of a Single Focused Cardiac Ultrasound Session on Cardiovascular Exam Confidence of First-Year Physician Assistant Students

Background: There is growing opinion in medical education that current clinicians-in-training have less expertise with physical examination than previous generations. Students’ exposure to abnormal physical exam findings can... [ view full abstract ]

Background:
There is growing opinion in medical education that current clinicians-in-training have less expertise with physical examination than previous generations. Students’ exposure to abnormal physical exam findings can be inconsistent due to variability in experiences via the current apprenticeship model. This model also results in few opportunities for students to be directly observed performing physical exams by skilled practitioners.

Variable exposure and limited direct observations can contribute to low student confidence in performing physical exams and recognizing abnormal pathology, which does not necessarily improve when students become interns and residents. In addition to self-identified poor confidence, various training programs have identified deficits in learners’ proficiency in the cardiac exam.

Several teaching methods have been employed to support first and second-year students in gaining physical exam skills, including simulation, observed structured clinical exams, and early clinical exposure. Bedside ultrasound is an emerging modality that offers a dynamic view of the relationship between structure and function. In our experience, ultrasound is well suited to the investigation of cardiac physiology in educational settings.

First-year medical students with basic ultrasound training have been shown to more accurately identify significant valvular cardiac disease with handheld ultrasound than trained cardiologists with physical examination. However, confidence with the traditional cardiac physical examination was not assessed in this study. In a recent study, simulation-based cardiopulmonary exam curriculum for physician assistant students demonstrated improvement in both learner confidence and examination skills.

The physician assistant program at our institution contains standardized ultrasound experiences in the didactic curriculum, whereas the medical doctorate curriculum has varying ultrasound exposure based on preceptorships and longitudinal advising groups.

Objective:
Evaluate the efficacy of a bedside cardiac ultrasound and simulation session on cardiac physical exam skill confidence and attitudes of first-year physician assistant students.

Methods:
The intervention consisted of a voluntary cardiac ultrasound and physical exam session for first-year physician assistant students at a tertiary academic center. This session included an introductory cardiac ultrasound lecture followed by rotations through four hands-on ultrasound stations. Three stations focused on visualizing cardiac anatomy and physiology by obtaining basic cardiac ultrasound views, then correlating these observations with auscultation of the chest. One station utilized a transthoracic echo (TTE) simulator (developed by Dr. Florence Sheehan at University of Washington) to demonstrate valvular pathology. Students correlated TTE images with cardiac doppler ultrasound clips , audio examples of murmurs (compiled from open access online resources) and written descriptions.

Data collection consisted of pre & post-intervention surveys which were anonymous to encourage student participation, and also pending IRB approval for assignment of identifiers allowing paired t-testing. Using a 5-point Likert scale, respondents indicated their self-confidence in cardiac physical examination skill, and perceived ability to identify the following elements of the cardiac exam: S1, S2, and aortic stenosis and mitral regurgitation murmurs. Students recorded prior ultrasound experience.


Results:
The overall response rate on the pre-intervention survey was 22/22 students, and 17/22 on the post-intervention survey.

Pre-session, the majority, (57%) of students were not confident in their cardiac exam skills. Only 68% of students felt confident in identifying S1 and S2 by auscultation. Only 4 (1.8%) students felt confident identifying an aortic stenosis murmur. Only 1 student felt confident identifying a mitral regurgitation murmur.

Post-session, 94% of students felt confident in identifying S1 and S2. Eight (47%) students felt confident identifying an aortic stenosis murmur by auscultation. Seven (41%) students felt confident identifying a mitral regurgitation murmur.

Mean responses for confidence increased after the intervention in each of the survey questions, as will be demonstrated in graphs.


Conclusion:
Our findings demonstrate that a single cardiac ultrasound teaching session was successful in improving overall student confidence in the cardiac physical exam. The element of the physical exam in which confidence was most improved was identification of mitral regurgitation. Student felt they improved the least in identification of S3 and S4 gallops, which were not extensively covered in the teaching sessions due to time constraints.

This pilot did not assess for objective improvement in recognition of normal and abnormal heart sounds. Further studies could evaluate both confidence and performance in conjunction. Additionally, future studies after IRB approval of identifiers could include statistical analysis with paired T-tests to allow for generation of p-values.

References available with full text.