COVID by the numbers: Explaining the sudden drop in emergency room visits

Posted at 5:00 PM, Sep 23, 2020
and last updated 2020-09-23 22:34:35-04

PHOENIX — At some point in the last few weeks, one of Arizona’s hospital systems stopped updating their bed counts. So, when the Arizona Department of Health Services updated the COVID-19 dashboard, one number stuck out.

Emergency room visits by COVID-19 patients suddenly dropped from 867 to 701.

This metric has been surprisingly level since August 27, with a range of 811 to 930 and a daily average of 867. Today’s drop of 166 visits is the largest movement in any direction since July 14.

The department of health’s COVID-19 dashboard tracks COVID-19 patient and bed counts daily on their dashboard. Three of the pages, “Hospital Bed Usage & Availability”, “Ventilator Usage & Availability”, and “Hospital COVID-19 Specific metrics contain data that is aggregated by the department but is otherwise entirely self-reported by the hospital systems. AZDHS told ABC15 that if a system fails to update, the most recent data will simply carry over daily until it is updated again. All of the data points in these tabs were impacted by the hospital system's failure to update the data.

So how did this impact the state’s COVID-19 data?

Aside from emergency room visits and hospital discharges, which saw aggressive changes from yesterday, other metrics didn’t appear as impacted. Inpatient beds, the catch-all term for all available hospital beds that can be utilized by COVID-19 patients that are not in the ICU increased from 527 to 583. However, the number has been experiencing an increase since it reached a reporting low on 9/19 of 472. COVID-19 ICU bed usage dropped from 122 to 114, a record low, ventilator use ticked up from 47 to 62, and intubations increased from 50 to 55.

The failure to report is one possible explanation for why COVID-19 emergency room visits remained level, while the COVID-like-illness (CLI) surveillance system run by the Centers for Disease Control was showing a decrease in emergency room visits for the past several weeks.

It is unclear which hospital system failed to update their numbers. The health department told ABC15 that they are working with the system to backdate the missing data.