Assessing the Relationship Between Emergency Department Boarding and Inpatient Unit Occupancy in Psychiatry

Emergency department (ED) boarding of patients awaiting inpatient admission is a widespread challenge. Patients presenting for psychiatric reasons face disproportionate rates and durations of boarding. Prior literature suggests higher occupancy levels on inpatient medical units increases ED boarding, but this relationship has not been examined in psychiatry. The goal of this study was to examine the association between inpatient psychiatry occupancy levels and psychiatric ED boarding.

This was a retrospective operational data analysis in an integrated healthcare delivery system. The study population included patients presenting to EDs requiring inpatient psychiatry placement. Separate analyses were conducted for adult, child/adolescent, and geriatric populations. Data were obtained from operational dashboards created from electronic health record data. Generalized additive models were used to assess the relationship between inpatient psychiatry unit occupancy and ED boarding volume.

Among the adult population, higher inpatient psychiatry unit occupancy was associated with higher psychiatric ED boarding volume (for example, daily predicted boarding volume was 31.6 (95% confidence interval [CI] 27.6-35.6) at < 80% occupancy and 41.0 (95% CI 37.3-44.8) at ≥ 90% occupancy. For the child/adolescent population, higher occupancy was also associated with higher boarding volume, but at a lower occupancy threshold (≥ 60%). There was not a significant association between boarding and occupancy for the geriatric population.

Higher inpatient psychiatry occupancy levels were associated with greater ED boarding, with the relationship best explained by boarding volume rather than duration. This possibly reflects dynamics in boarding and placement specific to psychiatry, including challenges of finding appropriate units for complex patients. In addition, health system factors that block beds (for example, staffing or infection status) likely influence the relationship between occupancy and boarding and should be incorporated into operational analyses aimed at reducing ED boarding.