RESUMEN
The diagnostic accuracy of handheld ultrasound (HHUS) devices operated by newly certified operators for pneumonia is unknown. This multicenter diagnostic accuracy study included patients prospectively suspected of pneumonia from February 2021 to February 2022 in four emergency departments. The index test was a 14-zone focused lung ultrasound (FLUS) examination, with consolidation with air bronchograms as diagnostic criteria for pneumonia. FLUS examinations were performed by newly certified operators using HHUS. The reference standard was computed tomography (CT) and expert diagnosis using all medical records. The sensitivity and specificity of FLUS and chest X-ray (CXR) were compared using McNemar's test. Of the 324 scanned patients, 212 (65%) had pneumonia, according to the expert diagnosis. FLUS had a sensitivity of 31% (95% CI 26-36) and a specificity of 82% (95% CI 78-86) compared with the experts' diagnosis. Compared with CT, FLUS had a sensitivity of 32% (95% CI 27-37) and specificity of 81% (95% CI 77-85). CXR had a sensitivity of 66% (95% CI 61-72) and a specificity of 76% (95% CI 71-81) compared with the experts' diagnosis. Compared with CT, CXR had a sensitivity of 69% (95% CI 63-74) and a specificity of 68% (95% CI 62-72). Compared with the experts' diagnosis and CT diagnosis, FLUS performed by newly certified operators using HHUS devices had a significantly lower sensitivity for pneumonia when compared to CXR (p < 0.001). FLUS had a significantly higher specificity than CXR using CT diagnosis as a reference standard (p = 0.02). HHUS exhibited low sensitivity for pneumonia when used by newly certified operators.
RESUMEN
BACKGROUND: This scoping review was conducted to provide an overview of the evidence of point-of-care lung ultrasound (LUS) in emergency medicine. By emphasizing clinical topics, time trends, study designs, and the scope of the primary outcomes, a map is provided for physicians and researchers to guide their future initiatives. RESEARCH QUESTION: Which study designs and primary outcomes are reported in published studies of LUS in emergency medicine? STUDY DESIGN AND METHODS: We performed a systematic search in the PubMed/MEDLINE, Embase, Web of Science, Scopus, and Cochrane Library databases for LUS studies published prior to May 13, 2023. Study characteristics were synthesized quantitatively. The primary outcomes in all papers were categorized into the hierarchical Fryback and Thornbury levels. RESULTS: A total of 4,076 papers were screened and, following selection and handsearching, 406 papers were included. The number of publications doubled from January 2020 to May 2023 (204 to 406 papers). The study designs were primarily observational (n = 375 [92%]), followed by randomized (n = 18 [4%]) and case series (n = 13 [3%]). The primary outcome measure concerned diagnostic accuracy in 319 papers (79%), diagnostic thinking in 32 (8%), therapeutic changes in 4 (1%), and patient outcomes in 14 (3%). No increase in the proportions of randomized controlled trials or the scope of primary outcome measures was observed with time. A freely available interactive database was created to enable readers to search for any given interest (https://public.tableau.com/app/profile/blinded/viz/LUSinEM_240216/INFO). INTERPRETATION: Observational diagnostic studies have been produced in abundance, leaving a paucity of research exploring clinical utility. Notably, research exploring whether LUS causes changes to clinical decisions is imperative prior to any further research being made into patient benefits.