Background Previous studies have indicated that crowding within the Emergency Department (ED) is associated with longer lengths of stay in the ED and higher mortality. Boarding, the time patients spend waiting for an inpatient bed after ED assessment, represents a clinically unproductive delay, and occupies scarce ED resources. We aimed to explore the impact of medical patients boarding not only on their outcomes but also indirectly on other patients in the ED and in and awaiting ambulances.

Methods A retrospective cohort study using routine data for 3 EDs in England from June 2021 to May 2024 was performed. Direct outcomes of medical patient boarding time were investigated: inpatient length of stay, 30-day readmission rate and mortality. Indirect outcomes of medical patient boarding levels consisted of time in ED for non-admitted patients, ambulance handover times, and ambulance response times. Regression analysis was used to model each relationship while controlling for other potentially confounding variables.

Results In all, data on 223,856 ambulance responses, 117,800 ambulance handovers, 367,985 non-admitted ED patients, and 46,976 medical admissions were studied. Medical patients, covering two-thirds of ED admissions, constituted 82% of total ED boarding time. Regression analysis showed that for a typical 25-bed ED, each additional five medical boarders was associated with an extra 12 and 39 minutes for Category 2 and 3 ambulance response times (p<0.001) and an extra 20 minutes for ambulance handover times (p<0.001). For admitted medical patients, each additional 4 hours of boarding time was associated with an extra 13 hours inpatient length of stay (p<0.001) and a 6% increase in odds of 30-day mortality (p<0.01).

Conclusion Boarding of medical patients in the ED is associated with direct harm for those patients, and indirect harms for other patients in the ED and awaiting ambulances.

What is already known on this topic A prolonged length of stay in the Emergency Department is known to increase mortality for those patients.

What this study adds Medical admissions make up 85% of boarding time in the ED waiting for an inpatient bed. This delay affects them directly with increased mortality, readmission and length of stay. It affects other patients with delayed ambulance offload and ambulance response times for other patients.

How this study might affect research, practice or policy The boarding delay for medical patients in the ED results in a longer inpatient length of stay and therefore fewer beds available for future patients. Stopping this practice would free up much needed hospital capacity, improve ambulance response times, and reduce mortality.

The authors have declared no competing interest.

This study did not receive any funding

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