# The effect of emergency department occupancy on the revisitation rate within seven days among patients discharged by triage

## TL;DR

This study found that higher emergency department occupancy is linked to a slightly increased chance of patients returning within seven days after being discharged by triage.

## Contribution

The study is the first to examine the impact of ED occupancy on revisitation rates among patients discharged by triage.

## Key findings

- High ED occupancy was associated with a 29% increased odds of revisitation within seven days.
- Age and comorbidities were strongly linked to both revisitation and hospitalization.
- ED occupancy did not significantly affect hospitalization rates after revisitation.

## Abstract

Emergency department (ED) crowding has been repeatedly shown to affect patient outcomes negatively. However, there is limited research on its impact on patients immediately discharged by the triage team. This study aimed to evaluate the effect of ED occupancy level on the rates of ED revisitation and hospitalization within seven days among patients discharged or redirected by the triage team.

An observational single-center study was conducted at the Tampere University Hospital ED from January 1, 2023, to December 31, 2024. The study population consisted of patients who were discharged or redirected by the ED triage team. These patients were divided into two groups: (1) patients who revisited the ED within seven days and (2) patients who did not return within seven days. A subgroup analysis focused on revisits that resulted in hospitalization. ED occupancy at the time of triage was considered as a predicting factor for revisitation and hospitalization. Age, sex, triage shift, and the updated Charlson Comorbidity Index (uCCI) were adjusted for in a multivariable logistic regression analysis.

Of the 180,267 ED visitors during the study period, 8.8% (n = 15,910) were discharged by the triage team. Of these, 8.7% (n = 1392) revisited the ED within seven days, and 16.2% (n = 225) of the revisiting patients were hospitalized. In the multivariable analyses, the highest quartile of ED occupancy was associated with an increased likelihood of ED revisitation (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.06–1.57). Older age was linked to both revisitation and hospitalization (OR for a 1-year increase 1.01 [95% CI: 1.01–1.02] and 1.02 [95% CI: 1.02–1.03], respectively). The uCCI score was also associated with revisitation and hospitalization (OR for a 1-point increase 1.13 [95% CI: 1.07–1.18] and 1.23 [95% CI: 1.13–1.33], respectively).

The highest ED occupancy quartile was associated with a modestly increased likelihood of an ED revisit but not hospitalization within seven days after being discharged by the triage team. Furthermore, age and comorbidities were associated with both revisitation and hospitalization.

Clinical trial number: not applicable.