Prehospital emergency department care activations during the initial COVID-19 pandemic surge.

Objective: To describe trends in prehospital presentations of critical medical and trauma conditions during the COVID-19 pandemic using prehospital and emergency department (ED) care activations.

Methods: Observational analysis of ED care activations in a tertiary, urban ED between March 10, 2020 and September 1, 2020 was compared to the same time periods in 2018 and 2019. ED care activations for critical medical conditions were classified based on clinical indication: undifferentiated medical, trauma, or stroke.

Main outcome: The primary outcomes were the number of patients presenting from the prehospital setting with specified ED activation criteria, total ED volume, ambulance arrival volume, and volume of COVID-19 hospital admissions. Locally weighted scatterplot smoothing curves were used to visually display our results.

Results: There were 1,461 undifferentiated medical activations, 905 stroke activations, and 1,478 trauma activations recorded, representing absolute decreases of 11.3, 28.1, and 20.3 percent, respectively, relative to the same period in 2019, coinciding with the declaration of a public health emergency in Connecticut. For all three types of presentation, post-peak spikes in activations were observed in early May, approximately two weeks after our health system in Connecticut reached its peak number of COVID-19 hospitalizations-eg, undifferentiated medical activations: increase in 280 percent, n = 140 from 2019, p < 0.0001-and declined thereafter, reaching a nadir in early June 2020.

Conclusions: After the announcement of public health measures to mitigate COVID-19, ED care activations declined in a large Northeast academic ED, followed by post-peak surges in activations as COVID- 19 cases decreased.