Chest
Volume 135, Issue 6, June 2009, Pages 1416-1420
Journal home page for Chest

Original Research
Chest Ultrasonography
Assessment of Left Ventricular Function by Intensivists Using Hand-Held Echocardiography

https://doi.org/10.1378/chest.08-2440Get rights and content

Background

Bedside transthoracic echocardiography (TTE) provides rapid and noninvasive hemodynamic assessment of critically ill patients but is limited by the immediate availability of experienced sonographers and cardiologists.

Methods

Forty-four patients in the medical ICU underwent near-simultaneous limited TTE performed by intensivists with minimal training in echocardiography, and a formal TTE that was performed by certified sonographers and was interpreted by experienced echocardiographers. Intensivists, blinded to the patient's diagnosis and the results of the formal TTE, were asked to determine whether left ventricular (LV) function was grossly normal or abnormal and to place LV function into one of the following three categories: 1, normal; 2, mildly to moderately decreased; and 3, severely decreased.

Results

Using the formal TTE as the “gold standard,” intensivists correctly identified normal LV function in 22 of 24 cases (92%) and abnormal LV function in 16 of 20 cases (80%). The κ statistic for the agreement between intensivist and echocardiographer for any abnormality in LV function was 0.72 (95% confidence interval [CI], 0.52 to 0.93; p < 0.001). Intensivists correctly placed LV function into one of three categories in 36 of 44 cases (82%); in 6 of the 8 cases that were misclassified, the error involved an overestimation of LV function. The κ statistic for agreement between the intensivist and echocardiographer with regard to placement into one of three categories of LV function was 0.68 (95% CI, 0.48 to 0.88; p < 0.001).

Conclusions

Intensivists were able to estimate LV function with reasonable accuracy using a hand-held unit in the ICU, despite having undergone minimal training in image acquisition and interpretation.

Section snippets

Study Population

This study was performed in the medical ICU of Hennepin County Medical Center, an urban teaching hospital affiliated with the University of Minnesota. The study population included 44 patients who had a formal TTE ordered by their primary physician because of one or more of the following indications: hypotension (n = 19); dyspnea-hypoxemia (n = 17); unexplained tachycardia (n = 4); increased troponin levels (n = 3); and abnormal ECG (n = 3).

Training and Interpretation of Focused TTE by Intensivists

Prior to beginning the study, intensivists involved in

Results

The 44 patients included 28 men (64%) and 16 women (36%) with a mean (± SD) age of 60 ± 16 years. The most common primary diagnoses were sepsis (n = 10), pulmonary edema (n = 6), pneumonia (n = 6), and seizure (n = 5); the remaining 13 patients had other miscellaneous conditions. Eighteen of the 44 patients (41%) were intubated, and 8 patients (18%) required therapy with vasopressors. The time required to complete the limited TTE was ≤ 10 min in most cases.

We first assessed the ability of

Discussion

The goal of this prospective observational study was to determine whether intensivists who had undergone brief and focused training in echocardiography were able to assess LV function accurately using a miniaturized ultrasound unit. Using a near-simultaneous comprehensive TTE as the “gold standard,” intensivists were able to differentiate normal and abnormal LV function correctly in 86% of cases; in 82% of cases the intensivists correctly classified LV function as normal, mildly to moderately

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The authors have reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal.org/site/misc/reprints.xhtml).

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