Diagnosing acute dyspnea is a critical action performed by Emergency Department (ED) physicians. It has been shown that ultrasound (US) can be incorporated into the work-up of the dyspneic patient; but there is little data demonstrating its effect on decision-making. Objectives: 1) To examine the impact of a bedside, clinician-performed cardiopulmonary US protocol on the clinical impression of ED physicians evaluating dyspneic patients; and 2) to measure the change in probability of the leading diagnosis before and after US. Methods: Prospective observational study of ED physicians treating adult patients with undifferentiated dyspnea in an urban academic center. Exclusion: known cause of dyspnea after evaluation. Outcomes: 1) percentage of post-US diagnosis matching final diagnosis; 2) percentage of time US changed providers' leading diagnosis; and 3) change in providers' confidence with the leading diagnosis before and after US. An US protocol was developed and standardized prior to the study. Providers (senior residents, fellows, attendings) were trained on US (didactics, hands-on) prior to enrollment, and were supervised by an US faculty member. After patient evaluation, providers listed likely diagnoses, documenting the probability of their leading diagnosis (scale of 1-10). After US, providers revised their lists and probabilities. Proportions are reported as percentages with 95%CI and continuous variables as medians with quartiles. The Wilcoxon rank-signed test and Cohen's Kappa statistics were used to analyze data. Results: 115 patients were enrolled (median age: 61 [51, 73], 59% female). The most common diagnosis before US was CHF (41%, 95%CI, 32-50%), followed by COPD and asthma. CHF remained the most common diagnosis after US (46%, 95%CI, 38-55); COPD became less common (pre-US, 22%, 95%CI, 15-30%; post-US, 17%, 95%CI, 11-24%). Post-US clinical diagnosis matched the final diagnosis 63% of the time (95%CI, 53-70%), compared to 69% pre-US (95%CI, 60-76%). Fifty percent of providers changed their leading diagnosis after US (95%CI, 41-59%). Overall confidence of providers' leading diagnosis increased after US (7 [6, 8]) vs. 9 [8, 9], p: 0.001). Conclusions: Bedside US did not improve the diagnostic accuracy in physicians treating ED patients presenting with acute undifferentiated dyspnea. US, however, did improve providers' confidence with their leading diagnosis.
2017
Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health