RESUMEN
OBJECTIVES: The Focused Assessment with Sonography in Trauma (FAST) is a point-of-care ultrasound (PoCUS) study that is routine in trauma patient assessment. Many organizations have published training guidelines, which grant competency through the completion of a fixed number of observed scans. This approach is incongruent with current trends in competency-based medical education. We aim to objectively quantify probe motion and user accuracy to differentiate groups of PoCUS operators. METHODS: Emergency medicine residents were recruited in two groups. The novice group (n = 15) had limited PoCUS experience, whereas the intermediate group (n = 14) had completed at least 50 supervised FAST examinations. Both groups underwent assessment on a live human model. Residents from the novice group returned (n = 9) after completing a curriculum and repeated the assessment using the identical experimental construct. RESULTS: Significant differences (p < 0.05) were found between the novice and both the intermediate and the novice returned groups in time, path length, and points of interest (POIs) scanned. Novices required more time to complete the full examination (290.82 seconds vs. 197.41 seconds vs. 271.79 seconds), utilized more motion (9392.07 mm vs. 4052.73 mm vs. 4985.05 mm), and imaged fewer POIs (48.13% vs. 95.00% vs. 100.00%) when compared to intermediates and returning novices, respectively. No difference was found between the intermediate and novice returned groups for the complete examination. Spearman's correlation was calculated between variables within each group. Correlations between time and path length were statistically significant (p < 0.05) with novice, intermediate, and novice returned values of 0.67, 0.65, and 0.90. Interestingly, neither time nor path length consistently correlated with POIs scanned in any group. CONCLUSION: Differences in probe motion efficiency and POIs scanned between novices and intermediate or returning novice users show promise for use as a quantitative objective assessment tool. Unlike in surgical literature, accuracy did not correlate with path length or time to examination completion.
RESUMEN
OBJECTIVES: Rapid assessment of left ventricular ejection fraction (LVEF) may be critical among emergency department (ED) patients. This study examined the predictive relationship between ED physician performed bedside mitral-valve E-point septal separation (EPSS) measurements to the quantitative, calculated LVEF. We further evaluated the relationship between ED physician visual estimates of global cardiac function (GCF) and calculated LVEF values. METHODS: A prospective observational study was conducted on a sequential convenience sample of patients receiving comprehensive transthoracic echocardiography (TTE). Three ED ultrasound fellows performed bedside ultrasound examinations to obtain both EPSS measurements and subjective visual GCF estimates. A linear regression analysis was conducted to examine the relation of EPSS to the calculated LVEF from the comprehensive TTE. Agreement (modified Cohen κ) between ED ultrasound fellow GCF estimates and the calculated LVEF was also assessed. RESULTS: Linear regression analyses revealed a significant correlation (r=0.73, P<.001) between bedside EPSS and the calculated LVEF. The sensitivity and specificity of an EPSS measurement of greater than 7 mm for severe systolic dysfunction (LVEF≤30%) were 100.0% (95% confidence interval, 62.9-100.0) and 51.6% (95% confidence interval, 38.6-64.5), respectively. Subjective estimates of GCF were moderately correlated with calculated LVEF (Cohen κ=0.58). CONCLUSIONS: Measurements of EPSS by ED physicians were significantly associated with the calculated measurements of LVEF from comprehensive TTE. Subjective visual estimates of GCF, however, demonstrated only moderate agreement with the calculated LVEF. An EPSS measurement greater than 7 mm was uniformly sensitive at identifying patients with severely reduced LVEF.
