Study Objectives
Emergency departments (ED) across the world continue to grapple with the COVID-19 pandemic. One growing concern is the ability to rapidly diagnose those infected with the SARS-CoV-2 virus. While rapid assays have proven beneficial in such contexts as strep pharyngitis and influenza, it is unclear whether the recent rapid COVID-19 assays will prove beneficial to ED flow. The purpose of this study is to assess the effect of a rapid COVID-19 assay on patient flow through two academic emergency department sites.
Methods
This was a retrospective, multi-facility study conducted between March 10, 2020 and May 9, 2020 at two university hospital EDs that are part of one health system. A rapid COVID-19 assay became available in our health system on April 10, 2020. Included were ED patients of all ages undergoing COVID-19 testing who were considered persons under investigation (PUI). PUIs tested between March 10, 2020 and April 9, 2020 via PCR testing served as the control group. Those tested between April 10, 2020 and May 9, 2020 via the rapid assay comprised the intervention group. Differences in length of stay (LOS) were analyzed between the two groups using T tests and multivariate regression.
Results
A total of 9,929 ED patient encounters occurred during the study period, and 3,137 PUIs underwent COVID-19 testing. Average age was 50 years. Fifty-six percent were male. 1,339 PUIs (42.7%) were tested with the PCR test during the control period. 1,798 PUIs (57.3%) were tested with the rapid assay during the intervention period. In the control group, 788 PUIs were discharged and 493 PUIs were admitted. In the intervention group, 512 PUIs were discharged and 1,129 PUIs were admitted. Mean length of stay (LOS) was 341 minutes and 489 minutes for PUI seen in the control period and in the intervention period, respectively (p<.001). When parsed by disposition, differences in mean LOS remained significant for those who were discharged (p<.001), but not for those who were admitted (p=0.35). After controlling for severity index, disposition, and demographic factors, testing with the rapid assay during the intervention period remained associated with an increased length of stay of approximately 95 minutes (95% CI 72-118, p<.001).
Conclusion
The use of a rapid COVID-19 assay did not improve patient throughput in our ED and was associated with a longer LOS, especially among those discharged from the ED. Additional testing is needed to determine the utility of the rapid COVID-19 test among an ED population.