December 6, 2022

The Role of Emergency Department Observation Units in Pandemic Surge Response

Mallika Singh, MD
Department of Emergency Medicine
NYU Langone Medical Center

Chris Caspers, MD
Department of Emergency Medicine
NYU Langone Hospital—Long Island

Emergency departments (EDs) have functioned as the clinical safety net for society since their inception. During pandemics, these safety nets are heavily impacted, due to the stress placed on critical resources by surging patient volumes combined with increased rates of morbidity and mortality.1,2,3,4,5 The COVID-19 pandemic placed a significant stress on the healthcare system through higher ED volume, greater inpatient admission rates coupled with decreased throughput, ED crowding, and numerous infrastructural demands created by infection prevention and control.6,7,8,9,10 As observation units (OUs) have historically extended the safety net provided by the ED by delivering short-term care to create additional ED and hospital bed capacity, OUs were one of many innovative and significant care models utilized to address the pandemic-related patient surge.1,6,11,12,13 OUs were employed by hospital systems as a physical space within the hospital, virtual space within the hospital, and in novel ways through virtual or home care systems to assist with surging patient volumes and reduce overall ED boarding. 3,4,5,6,7,11,14,15

Previous literature has shown that OUs offer flexible, scalable delivery models during times of disaster.1 During the COVID-19 pandemic, three case studies add to this literature by demonstrating how OUs can be leveraged to address capacity constraints during a disaster such as a global pandemic. At New York University Langone Health, the OU was restructured through staffing reallocation and unit relocation as the acuity of the patient population presenting to the ED drastically changed. At Mt. Sinai Hospital System, the OU was expanded into an ED-ICU unit to meet the needs of critically ill COVID-19 patients.15 At Atrium Health Hospital System, an at-home and virtual OU plan was fast-tracked to provide the health system with additional inpatient capacity.14 Each of these case studies illustrates how OUs mitigated the challenges faced by the ED through the reallocation of physical space and infrastructure, redeployment of staff to fill requirements, and extending care into the virtual space.

The COVID-19 pandemic catalyzed health systems to make swift decisions and implement innovative solutions to manage the disruption created by pandemic-related surges in patient volume, morbidity, and mortality. The COVID-19 pandemic highlighted the importance of flexibility, interdisciplinary collaboration, and managing infrastructural challenges. The ability, experience, and protocols generated from repurposing an OU or expanding remote OU health services is invaluable, as we will likely continue to face pandemics or similar disruptions throughout our lifetime.


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