Acute care hospitals are continually evolving their approach to adult inpatient care. They are searching for ways to best serve patients and their families while reducing operational costs. This has resulted in the rethinking of the established model of three levels of inpatient care: critical (intensive) care, intermediate (stepdown/progressive) care, and medical/surgical (general acute) care.

For many hospitals, this reevaluation includes how many levels of care are provided and how colocating acuity levels can reduce patient transfers, which are both operationally costly and potentially detrimental to patients. With the largest replacement of inpatient beds underway since the 1960s, there is an unprecedented opportunity to reshape inpatient care, supporting operational change through building design. Some of the greatest change is occurring through a logical colocation of critical and intermediate care, so that there are only two types of inpatient units with the hospital.

There have been many bold experiments, most notably, the pioneering unit at Clarian Methodist in Indianapolis. It sought to design an acuity adaptable room and unit for all three levels of acuity. This type of unit has had limited success in two settings: cardiovascular or other specialty units where the length of stay and type of treatment is predictive, and very low-acuity community hospital settings where there is less variation between the levels. The main challenges are:

  • Staff designation: Cross training of staff to absorb all levels of patients is problematic. Besides acquiring knowledge to service all levels, staff is usually best suited to either the intensity of the critical care experience or the more nurturing aspects of the alert medical/surgical patient.
  • Staffing ratios: Nursing assignments are difficult to arrange on these units where ratios range from a 1:2 to 1:5. How do managers determine the number of patients per nurse on a day-to-day basis?
  • Physical constraints: The visibility of patients that is desired on a critical care and, as we will see, on an intermediate care unit, conflicts with desired visual and acoustical privacy necessary on a typical general nursing unit.

As a result, many hospitals are now looking to reduce to the two types of units: critical/intermediate care and general medical/surgical. To understand how these acuity levels could be combined, we need to review the definition of each unit, the patients they serve, and their physical attributes:

Adult intensive (critical) care unit

The specialized critical care unit first appeared as a ventilator unit for polio victims in Copenhagen in the mid 1950s, but did not gain wide acceptance in the United States until the 1960s, when ABC (airway, breathing, and circulation) protocols were established and mechanical ventilation and cardiac defibrillation developed. The first Consensus Conference on Critical Care Medicine, convened by the National Institutes of Health (NIH), did not occur, however, until 1983, and the first guidelines for intensive care (ICU) admission, discharge and triage, and physical design not until 1988.

The Society of Critical Care Medicine (SCCM) defines the ICU as a “place for monitoring and care of patients with potential severe physiological instability requiring technical and/or artificial life support.” Without question, this includes unstable patients needing ventilator support and continuous invasive monitoring. The SCCM states that ICU care has no benefit over conventional care when there is “relatively no risk of death and exceedingly high risk of death.”

This highest acuity level translates into a typical nursing ratio of 1:2 patients. In many hospitals, the medical intensivist specialty supports this by providing individualized overview of the patients housed on that unit in a “closed” setting.

Historically, the first units built specifically for critical care were usually the first private patient rooms in a hospital populated by semiprivate rooms or even wards. The latest SCCM design guidelines published in 1988 and updated in 1995 reflect this specialization, prescribing an 8- to 12-bed unit with controlled access as optimal. The preferred design provided a direct line of vision between the central nursing station and the patient. In this original model, families are only addressed as visitors who remain in the waiting area unless allowed controlled access by the receptionist.

Some issues have remained consistent since the publishing of these guidelines. The current 2006 AIA Guidelines for Design and Construction of Health Care Facilities require a 13-foot clear headwall and a larger room size and greater clearances than a typical inpatient room to house more equipment and staff (figure 1). Service delivery includes the most power and medical gas requirements outside of interventional settings. The easy movement of beds, often with multiple equipment and staff support, is important. The need for fluid disposal within the patient room is desirable. Openness and visibility allow for caregivers to monitor situations across the unit.

Many intermediate care units are beginning to meet critical care clearance requirements for future acuity flexibility and to accommodate family needs

Dramatic changes in the last 13 years are changing critical care design, however, and making the potential combination with intermediate care possible. The additional complexity and reliability of electronic monitoring, including remote monitoring, have made the direct visibility of the patient head not nearly as critical as before. Development of electronic medical record keeping has allowed for a more decentralized nursing model, bringing more charting to bedside or immediately outside the room. Toilet rooms have become commonplace on cardiac intensive care units and are being included on other intensive care units, as well (figure 2). Studies in the last five years have supported new guidelines for interaction with patients’ families, concluding that more family interaction in medical decisions and care delivery is desirable and improves medical outcomes (figure 3). However, this accommodation of families within the critical care room is still controversial in many quarters.

This flexible room design for the most acute patients incorporates all the clearance requirements for critical care, as well as a full toilet room and family respite area. These is full visibility of patients by staff from the clinical workstations

The prototype intermediate/critical care patient room design allows for families to choose to be “off stage,” separated by sliding translucent panels when respite is needed. The room will accommodate either a headwall or ceiling/wall boom for service delivery

Adult intermediate (stepdown or progressive) care

The SCCM guidelines developed in 1998 define intermediate care as a unit where the patients do not require intensive care but need more care than on a typical medical/surgical unit. These patients “may require frequent monitoring of vital signs and/or nursing interventions, but usually do not require invasive monitoring.” Studies in the late 1990s proposed a separate unit designation based on investigations showing that a quarter to a third of ICU patients did not need this high level of care. The other reason for this type of unit is the reduction in labor costs. The recommended nursing ratio for this type of patient is 1:3.

The SCCM guidelines stated that the intermediate care unit would “improve patient/family satisfaction by providing a physical environment that is quieter and calmer than an ICU,” based on the prevailing ICU design of the time. These patients become more aware of their environment as their condition improves, and become ambulatory over time. Practitioners interviewed agreed that the intermediate care patient, in reality, requires more visualization than a critical care patient, since they are more prone to agitation and falls. Also these patients, in many cases, are able to negotiate toilet rooms with staff assistance.

Most current intermediate care units are former medical/surgical floors converted for this use by the addition of telemetry monitoring. Sometimes these are semiprivate beds converted to private rooms for the increased acuity level, allowing greater space for equipment, such as ventilators. The 2006 AIA Guidelines address specific requirements for the intermediate care unit for the first time. Besides requiring more space in patient rooms than a typical medical/surgical unit—including greater clearances around the bed—the AIA Guidelines prescribe that “There shall be direct or remote visual observation between … staffed charting stations and all patient beds in the unit.” The SCCM suggests that discharge from intermediate to a general unit occurs when the “patient’s physiological status is stabilized and need for intensive patient monitoring is no longer necessary.”


Although colocation of three levels of care may be infeasible in most settings, a combination of critical and intermediate care has become more desirable for many reasons:

  • Visibility of the patient, with intermediate care mobile patients most at risk for agitation or falls.
  • Similar needs of additional patient room and unit square footage to house support equipment, including ventilators.
  • Encouragement of family involvement, making designated family space within the patient room desirable in both settings.
  • Incorporating patient toilets in both settings (although the addition of a patient shower is still in question).
  • Similar nursing ratios (1:2, 1:3), which make flexible staffing not as onerous.
  • Increased desire for reduced noise levels in critical care, similar to that of less acute areas.
  • Decentralization of nursing workstations utilizing electronic medical record keeping, creating more flexible unit design.
  • Since most intermediate care patients “stepdown” from critical care, this reduces a major source of patient transfer.

The case histories (see sidebar) review two projects in design that exemplify the change in the way we consider critical and intermediate care. HD

Sheila F. Cahnman, AIA, ACHA, LEED AP, is the HOK Group Vice- President and Practice Leader in Chicago.

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Case Histories

Following are two major projects highlighting the latest trends in critical and intermediate care design, for both of which HOK served as design architect:

Beaumont Hospital

Beaumont Hospital in Royal Oak, Michigan, a Detroit suburb, is a 1,061-bed major academic and referral center with Level I trauma status. After just completing a major 656,000-square-foot bed tower and diagnostics and treatment addition in 2004, Beaumont had an acute need to expand their burgeoning emergency center, which has over 110,000 visits per year. They also needed to expand and update their surgery department.

Looking to the future, Beaumont realized their bed complement for their highest-acuity patients needed to grow. The new project, scheduled to open in 2011, includes a 87-bay emergency center, a surgery floor, and a 36-bed critical/intermediate care patient floor, with expansion potential to add four more floors and 144 more beds.

Beaumont could not predict exactly what proportion of their most acute patients would require critical versus intermediate care over the life of the building and therefore wanted to develop units that could easily adjust nursing ratios depending on census. The idea was to develop two 18-bed units per floor, with six beds on each side of a triangle (figure 4), so that the staffing ratio could easily adjust from 1:2 to 1:3. Thirty-six beds per floor was of manageable size for nursing administration.

At Beaumont Hospital, the triangulated floor plate allows for maximum visibility of patients, and the overall footprint separates family and staff/supply flows

Families enter both triangular units from a light-filled public concourse with a combined waiting area and many amenities. Staff and materials enter via a central elevator core on the back side of the units. Visibility of patients, of utmost importance for intermediate care as well as critical care, is accomplished by moving the clinical care stations across the hall from the rooms so nurses can visualize multiple patients assigned to them at a time. Workstations are decentralized on the perimeter of the core. The support core is designed so that communication, access, and visualization are as open as possible across the unit in any direction.

The Ohio State University Medical Center

The Ohio State University has embarked on the largest building program in its history: a replacement of its James Cancer Hospital and creation of a new critical care tower. This project, scheduled to open in 2014, will develop a chassis for 420 new inpatient beds, including 144 critical care beds, a new integrated diagnostic and treatment platform, and an outpatient cancer research and treatment facility.

The typical patient floor in the new bed tower consists of a 36-bed cancer acute care unit and 24-bed critical care unit. Each has distinct attributes to support its function and mission.

The cancer acute care unit is designed based on the clinical concept of three 12-bed “neighborhoods,” with a separate nursing staff assigned to the needs of those 12 patients. Each grouping has its own central workstation and designated support space for clean supplies, medications, and equipment. Additional support spaces include a lab/office for translational research and pharmacy work area on each unit. Gathering spaces include three conference rooms for both staff and family meetings and a two-story family/patient lounge with dramatic views to support the James Cancer Hospital’s programs.

The critical care unit has two 12-bed linear units organized around two six-bed nursing groupings. All rooms, therefore, can have unobstructed views of the campus. Every three beds are visible to an open clinical work station. Each of 12 beds is supported by an enclosed team conferencing space, just-in-time clean storage/medications, and kitchen. The linear unit (figure 5) is supported by a “ghost” corridor for staff support, equipment, material, and patient transport away from the patient room corridor.

At the Ohio State University Medical Center, the decentralized clinical workstations allow for a linear departmental design, back-fed by a “ghost” corridor for staff and supply circulation

The entire building is serviced by an automatic guided vehicle (AGV) system that moves materials and waste to and from the patient units from two elevator core areas. Materials from these cores will also utilize this “ghost” corridor when possible. This will reduce noise transmission and congestion outside the patient rooms, isolating the internal corridor for direct patient care. Significant family support spaces include the family lounge space overlooking the building atrium including two private consult rooms for family/physician private meetings. Each unit has a translational research lab and office to further tOSU’s mission of personalized medicine.

Critical/intermediate care patient room

Both projects are considering a similar patient room design that meets all the highest critical care standards while allowing for the needs of the intermediate care (more ambulatory) patient (figures 2 and 3). The room design places the toilet/shower room on the exterior wall to allow for fully glazed corridor walls with breakaway ICU sliding doors, similar to a conventional ICU, for the highest visibility and bed maneuverability.

The exterior wall has a separate family respite area and private toilet/shower room. This area could be separated by translucent sliding doors for family privacy. The toilet room has a sliding door to create maximum access. A family member will be encouraged to “room in” with the patient when desired. The rooms are single-handed to allow patients to reach the toilet room via grab bar assists as they begin to walk for increased patient safety.

In both projects, the clinical workstations are across the hall from the patient rooms rather than in nursing “cockpits.” This allows nursing coverage of more than two adjacent rooms and gives more footprint to the room itself. Both projects are considering a wall-mounted articulated arm boom for greater flexibility of patient services and a staff computer station in each room.

The current room configuration is based on a 30-foot column grid with a net square footage—including a toilet room—of approximately 315 square feet. In both projects, the toilet room will be accessible, but will only meet ADA minimum compliance standards for the units.

Healthcare Design 2008 November;8(11):48-55