To evaluate the ability of the intensivists with limited echocardiography (ECHO) training to assess left ventricular (LV) performance with the portable ECHO machine.
4 intensivists had 2 hours of didactics and 4 hours of hands-on training in obtaining and interpreting echocardiographic images. 41 consecutive patients who had a standard ECHO during their MICU stay underwent a bedside examination by an intensivist. The bedside exam was performed and recorded with the SonoSite 180 machine on the same day as the standard ECHO. The LV performance was visually estimated as category 1 (ejection fraction (EF) > 50%), category 2 (EF 30 - 50%) or category 3 (EF < 30%). The recorded exams were independently graded by a staff cardiologist. All participants were blinded to the results of the standard ECHO. Comparisons between the interpretation of the bedside exam by the intensivist and the cardiologist were made. Discrepancies between the bedside exam and the standard ECHO were evaluated.
The review of the bedside exams by the cardiologist revealed category 1 LV performance in 18 patients (45%), category 2 in 14 (35%) and category 3 in 8 patients (20%). One recording was technically inadequate. The intensivists estimated LV function correctly in 72% of patients, overestimated in 23% and underestimated in 5% (kappa statistic = 0.55). The majority of discrepancies (10/11) were within 1 category range. The sensitivity of the bedside ECHO performed by an intensivist to detect any LV dysfunction was 77% and the specificity was 94%. The positive predictive value was 94%. The negative predictive value was 77%. When compared to the standard ECHO, suboptimal bedside images resulted in the discrepancy in 4 cases.
Medical intensivists were able to make a correct estimate of the LV EF in the majority of patients.Additional training in image acquisition and interpretation may improve the performance of the intensivists in the bedside echocardiography.
Bedside ECHO may become a valuable tool in rapid assessment of LV function in patients admitted to the MICU.
Roman Melamed, None.