Case Study: Evaluating Emergency Expansion

Midwest Hospital planned to expand and potentially replace its ED in response to increased crowding and congestion. Although the current number of annual visits (40,000) was not expected to grow significantly in the near future, the patient and visitor waiting room was frequently overflowing during the evening hours. ED staff also began creating “hall beds” by labeling and assigning defined stretcher bays in the hallways to gain additional treatment space during peak periods. The relocation of an adjacent occupational medicine clinic was viewed as an option for ED expansion in lieu of total ED replacement.

Specific facility expansion goals included expanding the patient and visitor waiting space with enhanced amenities; providing adequate exam and treatment space; triaging nonurgent patients in a separate, fast-track area; and developing a holding area for patients to be admitted who are waiting for an available inpatient bed. Although facility expansion and operations improvement were deemed necessary by all members of the planning team, the CFO was concerned about spending significant capital dollars when ED revenues were relatively flat. ED staff were also not in agreement regarding the extent of required expansion; some wanted to almost double the size of the current ED, while others were concerned that significant expansion would require additional staff at a time when budgets were tight and recruiting was difficult. Others were concerned about the long ED length of stay and its impact on customer satisfaction. However, all members of the planning team agreed that a detailed analysis of the relationship between improvements in exam and treatment room turnaround time and resulting space need and construction cost was warranted prior to initiating the detailed operational and space programming process.


A detailed database was assembled, and a number of operational issues were identified that would ultimately affect the overall size of the upgraded ED as follows:

  • Trend in ED utilization and patient mix. Historically, emergency visits at Midwest Hospital increased 2 percent to 4 percent annually; however, ED visits have stabilized at around 40,000 annual visits during the past two years. The leveling-off in volume has been generally attributed to a communitywide initiative to redirect the uninsured to primary care clinics. However, Midwest Hospital’s ED has been on diversion frequently because of a lack of intensive care beds at the hospital. Both the percentage of ED patients that are admitted (currently at 18 percent) and the percentage of nonurgent care patients (currently at 40 percent) have been increasing, even though total ED volume has stabilized.
  • Treatment room turnaround time. Currently, the average treatment room turnaround time at Midwest Hospital is more than three hours which is even longer when the time from initial triage to placement in the treatment room and the time from exiting the treatment room to eventual discharge are added. Critical operational issues include slow responsiveness from the imaging department for magnetic resonance imaging scans and long waiting times for physician consultations. The backup in the ED of patients to be admitted while they are waiting for an available inpatient bed is also a major issue.
  • Number of treatment bays. A total of 30 ED treatment spaces are currently available, including two large triage and resuscitation rooms and dedicated rooms for obstetrics-gynecology and orthopedic casting. Four of the treatment bays are designated for nonurgent patients, although they are generally used on a first-come-first-serve basis with no formal fast-track procedure in place. In addition, a dedicated x-ray and computed tomography rooms are located within the ED.
  • Average net square feet (NSF) per treatment bay. The existing treatment room or bay currently averages only 105 NSF, with some stretcher bays sized at less than 70 NSF compared to contemporary standards of 120 NSF for general ED treatment rooms; more than double the space is required for trauma and resuscitation rooms.
  • Total department gross square feet (DGSF) per treatment room/bay ratio. The ratio of the current amount of DGSF to the total number of treatment and procedure rooms (or bays) was evaluated to assess the adequacy of the overall footprint of the ED to support the current number of treatment rooms and bays. With 11,250 DGSF occupied by the current ED, an average of 375 DGSF per treatment space is calculated compared to contemporary design standards of 550 to 650 DGSF per treatment or procedure space. This indicates a severe shortage of support space and inadequately sized treatment cubicles.
  • Average annual visits per treatment bay. With 40,000 annual ED visits and 30 treatment bays and rooms, Midwest Hospital currently accommodates 1,333 annual ED visits per treatment room/bay.


An overview analysis of the impact of treatment room turnaround time on required ED treatment rooms, total DGSF, and total project cost was performed. The analysis revealed that even minor improvements in ED turnaround time would have a significant effect on the space and resulting renovation or construction costs, as shown below.

Impact of Treatment Room Turnaround Time on ED Space and Project Costs
(Assuming 40,000 Annual Visits)

Average Treatment Bay Turnaround Time 90
Treatment Bays Required 20 25 35
Gross Space Required (650 DGSF per Bay) 11,000 – 13,000 13,750 – 16,250 19,250 – 22,750
Estimated Project Cos $4.7 – $5.5 M $5.8 – $6.9 M $8.2 – $9.7 M


Because of the high cost of replacing the existing ED, particularly if 30 or more treatment cubicles and support space were provided, the ED planning team ultimately decided to focus their operations improvement efforts on improving ED treatment room turnaround time to a target of 120 minutes before embarking on a major renovation or construction project.

Because the adjacent occupational health clinic (with six exam rooms and support space) schedules patients only on Monday through Friday and is typically closed at 4:00 p.m. each day, and because ED demand for nonurgent (fast-track) space is typically from 4:00 p.m. until 11:00 p.m., an operational plan was developed to use the occupational health clinic’s space to triage and treat nonurgent ED patients during the evenings and on weekends. With the diversion of these nonurgent patients out of the main ED, the smallest ED treatment rooms and bays were reconfigured, resulting in 25 appropriately sized ED treatment rooms and cubicles in addition to the six fast-track exam and treatment rooms. A modest expansion of the patient and family waiting area was undertaken using adjacent office space. This interim solution allowed Midwest Hospital to monitor trends in ED volume and evaluate the success of its operations improvement efforts. Hospital leadership agreed to reevaluate the need for a major ED expansion or replacement project again in another year.

Note: Detailed calculations for determining the number of exam/procedure rooms and associated support space can be found in the SpaceMed Guide.

[This Case Study was updated from the original published online in July 2008; it is also included in Healthcare Facility Planning: Thinking Strategically (second edition) by Cynthia Hayward.]