Point-of-care lung ultrasound in emergency medicine: A scoping review with an interactive database.

BACKGROUND: We conducted a scoping review 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, we provide a map 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 before 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 after 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 (375, 92%), followed by randomized (18, 4%) and case series (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 before further research is made into patient benefits.