Prehospital Ultrasound: Nationwide Incidence from the NEMSIS Database.

We sought to describe prehospital ultrasound (PHUS) use and trends in PHUS utilization over time using a national database. Using the 2018 - 2021 National Emergency Medical Services Information System databases, we identified those EMS activations where PHUS was performed. We evaluated the association between year and number of PHUS exams performed using univariable and multivariable regression analysis. Analysis was performed on the overall group and various subgroups. In total, there were 148,709,000 EMS activations by 13,899 agencies over the 4 years. Of these, 3,291 unique activations (0.002%) involved PHUS, performed by 71 EMS agencies (0.5%). The annual rate of ultrasound evaluations per 1 million EMS activations significantly increased over the study period: 5.2 in 2018, 14.8 in 2019, 18.6 in 2020, and 38.9 in 2021 ( Prehospital ultrasound use in the United States increased significantly over the study period, but remains exceedingly rare. The performance of PHUS was recorded throughout the United States, with paramedics performing the majority of PHUS studies included in this database.