How many is enough? Measuring the number of FAST exams needed by emergency medicine trainees to reach competence.

Background: For patients with blunt abdominal trauma, the Focused Assessment with Sonography in Trauma (FAST) exam is the initial imaging modality employed to diagnose and risk stratify. A positive FAST exam in this patient population denotes intraperitoneal hemorrhage. In a hemodynamically unstable patient, it necessitates rapid surgical intervention. Ultrasound is highly dependent on the operator's ability to obtain quality images for interpretation. Failure to obtain adequate images prevents accurate interpretation and reduce its diagnostic accuracy. Previous studies evaluating whether the FAST exam can be improved solely by experience had conflicting results. None of those studies used an objective method to evaluate the FAST exam's quality. Our study aimed to objectively determine the number of FAST exams required by an emergency medicine (EM) resident to reach sufficient quality for independent scanning.

Methods: 59 first-year EM residents from a single site were included in this study. All FAST exams that were saved in the Qpath archival system by the 59 EM residents, whether the exam was performed for educational or clinical purposes, were reviewed, and scored using a Task-Specific Checklist (TSC) score. This score is an objective way to assess the proficiency and quality of the FAST scan. The TSC was based on whether the imaging of 24 specific anatomic landmarks, split into four anatomic regions, was completed successfully or not. The AEMUS (Advanced EM Ultrasonography) faculty provided feedback to trainees wither electronically via Qpath or at the bedside. According to the quality of ultrasound imaging and competence (QUICK Score), if the average TSC score for the first 10 exams was 18 or higher, the resident was considered an expert. However, if the resident failed to achieve that score, we skipped the first exam performed by the resident and the average score for the second through eleventh exams was then calculated. If the resident did not achieve the desired result, the first and second exams were skipped and the average score for the remaining 10 exams was determined. This sequence was repeated until the resident achieved an average score of 18 or higher on their TSC score.

Results: In total, 663 FAST scans performed by EM residents were scored. The average number of FAST exams needed for independent scanning is 11.23 (95% CI, 10.6-11.85). 66.1% of enrolled residents achieved an average score of 18 or higher in their first 10 FAST exams, and 33.8% of residents required more than 10 scans. The average scores for the right upper quadrant (RUQ), left upper quadrant (LUQ), pelvic, and subxiphoid views were 5 (95% CI, 4.88-5.1), 4.7 (95% CI, 4.59-4.8), 5.1 (95% CI, 4.96-5.24), and 3.7 (95% CI 3.6-3.8) respectively.

Conclusion: This study demonstrated that when constructive feedback on each FAST exam was given, the average first-year emergency medicine resident achieves competency in performing FAST exams independently after completing 10-12 (average of 11.23) FAST exams. Further research is required to validate the findings.