Characteristics of Patients Who Return to the Emergency Department After an Observation Unit Assessment.

Introduction: Emergency Department observation units (EDOU) transition patients from the emergency department (ED) to dedicated areas where they can receive continuous monitoring. Understanding patient return visits after EDOU discharge is important for optimizing healthcare. The objective of this study was to investigate the correlation between demographic and clinical features and the likelihood of returning to the ED within 30 days following their initial assessment in the EDOU.

Methods: This retrospective, observational cohort study of adult EDOU subjects was conducted between February 1, 2018 - January 31, 2023. Adult patients evaluated in the EDOU and returned to the ED within 30 days were identified. Subjects were compared to those assessed in the EDOU but did not return to the ED within 30 days. The analysis took into account multiple visits by the same subject and made adjustments for variables including gender, ethnicity, insurance status, primary diagnosis, and disposition, using a generalized linear mixed model.

Results: A total of 14,910 EDOU encounters were analyzed and 2,252 (15%) patients returned to the ED within 30 days. The analysis took into account several variables demonstrated a significant association with the likelihood of returning to the ED within 30 days. These included gender (p=0.0002), ethnicity (p=0.005), race (p=0.0004), insurance status (p<0.0001), primary diagnosis (p<0.0001), and disposition (p<0.001). Emergency severity index and length of stay were not associated with returning.

Conclusions: Understanding these factors may guide interventions, enhance EDOU care, and reduce resource strain. Further research should explore these associations and long-term intervention impacts for improved outcomes.