A Modified Lung and Cardiac Ultrasound Protocol Saves Time and Rules In The Diagnosis of Acute Heart Failure

SONOSIM SUMMARY: This study focuses on the potential of ultrasound to provide efficient bedside care and accurate patient diagnosis. More specifically, this research hopes to confirm the ability of a modified lung and cardiac ultrasound (US) protocol to differentiate between etiologies of acute dyspnea and acutely decompensated heart failure (ADHF), as well as improve time to diagnosis. Ultimately, findings found that cardiac US was a key component of the US protocol, and when completed properly, the modified protocol was very successful. Since the protocol only requires three views, diagnosis was efficient and accurate. The study concludes by confirming the success of their modified lung and cardiac US protocol, and suggests that further research should expand the study’s size and population to gain a better understanding of effectiveness in multiple ERs.

Russell FM, Ehrman RR. A Modified Lung and Cardiac Ultrasound Protocol Saves Time and Rules in the Diagnosis of Acute Heart Failure. J Emerg Med. 2017 Jun;52(6):839-845.

Abstract

Background
Multiorgan ultrasound (US), which includes evaluation of the lungs and heart, is an accurate method that outperforms clinical gestalt for diagnosing acutely decompensated heart failure (ADHF). A known barrier to ultrasound use is the time needed to perform these examinations.

Objective
The primary goal of this study was to determine the test characteristics of a modified lung and cardiac US (LuCUS) protocol for the accurate diagnosis of ADHF.

Methods
This was a secondary analysis of a prospective observational study that enrolled adult patients presenting to the emergency department with undifferentiated dyspnea. Intervention consisted of a modified LuCUS protocol performed by experienced emergency physician sonographers. A positive modified LuCUS protocol was defined as the presence of B+ lines in both the left and right anterosuperior lung zones, plus a left ventricular ejection fraction <45%. If all three of these findings were not present, the modified LuCUS result was interpreted as negative for ADHF. The primary objective was measured by comparing US findings to final diagnosis independently determined by two physicians, both blinded to US findings and each other’s final diagnosis.

Results
We analyzed data on 99 patients; 36% had a final diagnosis of ADHF. The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of the modified LuCUS protocol are 25% (95% confidence interval [CI] 14-41%), 100% (95% CI 94-100%), undefined, and 0.75 (95% CI 0.62-0.91%), respectively. This modified protocol takes on average 1 min and 32 sec to complete.

Conclusion
The point estimate for the specificity of the modified LuCUS protocol in this pilot study, accomplished by a reanalysis of data collected for a previously reported investigation of the full LuCUS protocol, was 100% for the diagnosis of ADHF.

To read the article, visit the Journal of Emergency Medicine website.

SonoSim Keywords: Ultrasound Education, Ultrasound Training, Lung, Cardiac Ultrasonography