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Disaster Alternate Care Facility Selection Tool

Public Health Emergency Preparedness

This resource was part of AHRQ's Public Health Emergency Preparedness program, which was discontinued on June 30, 2011, in a realignment of Federal efforts.

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Staffing Recommendations

Staffing an ACF is key to its successful operation and may be one of the largest challenges, depending on the nature of the incident. A review of the literature reveals that relatively few proposals have been put forth for staffing an ACF. One important work that has been used as the basis for some surge capacity plans is the Modular Emergency Medical System (MEMS) and two of its components, the Acute Care Center (ACC) and the Neighborhood Emergency Help Center (NEHC).1 MEMS was developed by the U.S. Army Soldier and Biological Chemical Command (SBCCOM) to create a concept of operations for a medical response package that could be created to increase the capacity of States and municipalities to handle a large influx of patients after a biological attack.

While MEMS was originally created to respond to bioterrorism, its principles can be applied to a variety of mass casualty scenarios. The key aspects of MEMS are:

  • Integrates all local medical aspects.
  • Allows a flexible and timely response through its modular design.
  • Serves as a framework to support a massive medical response.
  • Augments the existing medical system.
  • Is consistent with the Incident Command System.

The ability to develop and deploy these two expandable patient care modules is the foundation of MEMS. Both modules have application to the current concept of an ACF. The NEHC is designed to serve as a primary triage and evaluation facility capable of screening up to 1000 patients per day. At the NEHC, patients who are potentially exposed to an infectious agent can be screened and prophylactically treated and/or immunized. At the same time, information regarding the incident can be disseminated. The NEHC has limited treatment and holding facilities, so symptomatic patients would be directed to an appropriate health care facility or ACC. The NEHC staffing protocol calls for the following level of staffing:

Position Number
Facility Manager 1
Medical Section Operations Chief 1
Records/Planning Section Chief 1
Logistics Section Chief 1
Transportation Officer 1
Communications Officer 1
Maintenance Officer 1
Physician 3
Physician Assistant (PA) 1
Family Nurse Practitioner (NP) 1
Nurse 7
Paramedics 3
Clerks 14
Security Personnel 4
Housekeeping Personnel 2
Volunteers 32

The ACC on the other hand is a true ACF that has both treatment and patient holding capability. It is built around 50-bed subunits with staffing recommendations for the appropriate number of health care providers per subunit. The ACC model suggests the following staffing for a 12-hour shift per 50-bed subunit.

Position Number
Physician 1
Physician Assistant (PA) or Nurse Practitioner (NP) 1
Registered nurses (RN) and/or Licensed Practical Nurses (LPN) 6
Nursing Assistants and/or Nursing Support Technicians 4
Medical Clerks (Unit Secretaries) 2
Respiratory Therapist 1
Case Manager 1
Social Worker 1
Housekeeping Personnel 2
Patient Transporters 2

It should be remembered, however, that the ACC was, and is, a theoretical proposal that was originally designed to respond to a biological threat but has never actually been implemented. It is not unreasonable to assume, however, that it would also have applicability to other mass casualty situations. It is also interesting to note the omission of pharmacists from both the NEHC and ACC staffing guidelines, a staffing group that has proven to be invaluable in actual operation of ACFs.

Incorporating Real World Experience

After Hurricanes Katrina and Rita struck the Gulf Coast of the United States in the fall of 2005, both the health care system and municipal infrastructure of New Orleans and adjacent coastal areas were nearly destroyed, leaving thousands of people homeless with many requiring medical care. The medical care they needed was no longer available at local health care facilities that had been incapacitated by the storms. What followed was the largest disaster response operation in American history to date. Large shelters were set up in Louisiana and surrounding States for the evacuees and numerous ACFs were created to replace the collapsed health care system. This tragic event has served as a valuable learning opportunity to study how ACFs should operate.

ACF Staffing: The Katrina and Rita Experience

Table 1 compares data points on ACF staffing as reported from eight different ACFs that operated after Hurricanes Katrina and Rita in 2005. The first three rows describe the structure and function of each ACF. The following rows show the duration of operations and give available patient census numbers. Due to the difficulty of recordkeeping in a disaster, the numbers are estimates. Also, the daily patient load varied significantly. Most patients arrived in the early days of the operation and then the numbers of patients gradually tapered off leading to decommissioning of the ACF. Respondents were not able to provide exact daily patient census numbers that would allow for a precise statistical analysis of patient volumes and staffing requirements. Instead, the total number of patients seen is documented. In some cases a daily average and peak census were given.

The remaining rows document how many of each type of health care provider were on duty at a given time. Again, there was a great deal of flux in the post-disaster environment with day-to-day variability of the exact number of providers. The respondents were asked to give a number that represents an average of how many of each type of provider were present on any given day of the ACF operation.

Table 1: Hurricanes Katrina and Rita 2005 ACF Staffing Matrix

  Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 7
Function Pediatric shelter support General shelter support Ambulatory and inpatient health care replacement Ambulatory health care replace-ment Ambulatory and surgical health care replacement Special- needs in-patient care Ambulatory health care replace-ment
Structure Fixed facility Fixed facility Fixed facility Fixed facility Mobile Fixed facility Fixed facility
Inpatient Capability Y N Y N Y Y N
Days of Operation 13 16 NDA NDA 10 NDA NDA
Total Patients >3,500 >10,000 >6,000 >20,000 7400 200 400
Daily Average Census NDA 619 (+/- 301) NDA NDA 25-300 NDA NDA
Peak Daily Census 400 1,125 NDA NDA 500 NDA NDA
Shift Length (hours) 8, 12, or 24 4,8, or 12 8 for most, 12 for nurse managers 12 12 12 NDA
Day/Night Staffing Difference Y Y Y N Y Y NDA
Total Staff NDA 7 common staff / 1000 volunteers "several hundred" 50 60-100 100 300 at various times; daily total not listed
Physicians 6 16 AM /4 PM 25 NDA 11 4 7
Midlevel Providers (PA/NP) Present but number not recorded N 20 NDA 1-2 5 3
Nurses 5 20 50+ NDA 8-10 20 10
LPN/EMT N N 50+ NDA 8-10 NDA 1-2
Pharmacists 1 2/1 6+ 2-3 2-3 2 1-2
Clerks/Administrative 1 5 AM /1 PM 50+ 1-2 1-2 NDA 6

Y=yes or present but number unknown
NDA = No Data Available
Fields that have two numbers listed in a "x/y" format indicate a difference in staffing between day & night Due to difficulties with record keeping and in light of day-to-day variations in staffing, all numbers should be viewed as estimates.

Table 2 provides a look at the ratio of patients to providers at each site. Only Sites 1, 2, and 5 indicated how many days their site was operational. Without that data point as the denominator for all sites, the total number of patients seen per day is difficult to determine. As all surveyed sites were responding to the same overall event, the average of the number of days of operations of Sites 1, 2, and 5 (13 days) was arbitrarily applied to Sites 3,4,6,7, and 8 (grayed columns). The total number of patients was then divided by the actual or calculated number of days of operation to yield the number of patients seen per day. As previously noted, the daily census varied greatly depending on the number of days after the event.

Table 2: Ratios of Health Care Providers to Patients on a Daily Basis

  Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 7
Function Pediatric shelter support General shelter support Ambulatory and inpatient health care replacement Ambulatory health care replacement Ambulatory and surgical health care replacement Special needs inpatient care Ambulatory health care replacement
Structure Fixed facility Fixed facility Fixed facility Fixed facility Mobile Fixed facility Fixed facility
Days of Operation 13 16 13* 13* 10 13* 13*
Total Patients 3,500 10,000 6,000 20,000 7400 200 400
Daily Average Census 269* 625* 462* 1538* 740* 15* 31*
Numbers below reflect the ratio of a given category of provider to the number of patients seen on an average day
Physicians 1:45 1:39 1:18 NDA 1:67 1:4 1:4
Midlevel Providers (PA/NP) NDA NP 1:23 NDA 1:493 1:3 1:10
Nurses 1:54 1:31 1:9 NDA 1:82 1:1 1:3
LPN/EMT NP NP 1:9 NDA 1:82 NDA 1:16
Pharmacists 1:269 1:313 1:77 1:513 1:246 1:8 1:16
Clerks/Administrative 1:269 1:125 1:9 1:1025 1:493 NDA 1:5

NP = Type of provider Not Present
NDA = No Data Available
* Estimated; see text for details.

The daily census was divided by the number of each type of provider to find the ratio of each type of provider to patients seen per day. For example, Site 1 had a calculated daily average patient census of 269 and had an average of 6 physicians on duty per day, so the ratio of physicians to patients is 1:45. As these final ratios are based on several averages and assumptions, they should be taken only as first order approximations.

The final issue to consider when examining this data presented is that the ratios are simply the ratios that existed in each ACF. The data does not indicate that they are the correct ratios. None of the respondents reported being limited by the number of available personnel. There were also no comments in our questionnaire about adverse patient outcomes because of health care provider shortages. That being said, however, the survey instrument did not specifically ask respondents to suggest an ideal staffing ratio, nor did it specifically ask how their staffing ratio differed from what they thought would be ideal.

It is interesting to note, however, that the overall numbers of physicians and nurses (registered nurses and licensed practical nurses) are, in fact, very similar to the recommendations made in the MEMS documents. Thus, a suggested staffing consideration of one physician and six nurses for a 50-bed patient unit may represent a reasonable starting point for an ACF. These numbers can then be increased or decreased depending on the nature of the event and the specific role to be performed by the ACF.

ACF Credentialing

Table 3 summarizes some credentialing issues that had to be addressed by the various sites. One of the themes that emerged was that credentialing was somewhat easier if the responders were part of a previously established disaster response team under the control of either the Federal Government or a State government. A review of the medical literature (see references section) shows that many responders were part of Federal disaster response teams such as Disaster Medical Assistance Teams and Urban Search and Rescue teams, State disaster response teams such as the Illinois Medical Response Team, or military units. These types of teams have an advantage in that they have already gone through a credentialing process, have a government-issued identification card, and work together within a predefined command structure. Some of the other facilities involved in the response were operated under the auspices of local health care institutions and/or county health agencies. Those providers who were already credentialed by the sponsoring institution were easy to verify but these facilities had greater difficulty with incorporating volunteer providers from outside of the sponsoring system. Several respondents commented on the need for an improved system for credentialing providers ahead of time or credentialing them rapidly and efficiently after an event.

One system that has been developed is the Emergency Systems for Advance Registration of Volunteer Health Professionals (ESAR-VHP).2 This program is currently administered by the Office of the Assistant Secretary for Preparedness and Response (ASPR) in the U.S. Department of Health and Human Services (HHS). The goal is to create an electronic database of health care providers who are willing to volunteer to serve after a disaster. The system is designed to be administered separately in each State. Its goals are to:

  • Register health volunteers.
  • Apply emergency credentialing standards to registered volunteers.
  • Allow for the verification of the identification of the identity, credentials, and qualifications of registered volunteers in an emergency.

None of the survey respondents reported any significant contribution of the ESAR-VHP system to credentialing at their respective ACFs, possibly because the system was still in its early stages of State-based development. Several respondents did report that a system like ESAR-VHP could be valuable if it could be further developed and effectively implemented

Another resource that assisted with incorporating out-of-Sate health care providers into the local response was the Emergency Management Assistance Compact (EMAC) (Public Law 104-321).3 All personnel who respond to an event as part of a State's formal response to another State's formal request for aid theoretically are covered under the EMAC. Congress ratified EMAC in 1996 to allow more expeditious response of emergency medical resources and National Guard units from other States to the site of a disaster. EMAC gives four privileges and protections to responders. First, it promises that responders' licenses or certificates from their home State will be honored in the State to which that person is responding. However, the person must be part of the official response element; freelancers are not protected. Second, responders are likely to receive protection from malpractice claims that may arise from their service in the affected area. Third, responders are promised death and disability benefits, although this applies more to civilian responders. Finally, in theory, States that respond through EMAC should be reimbursed for any expenses they incur during response operations.

The sudden nature of the two hurricanes that struck the Gulf Coast in 2005 and the overwhelming number of displaced persons after New Orleans flooded necessitated a very rapid medical response and allowed little time for many ACFs to establish credentialing systems. There were reports of people impersonating health care providers to gain access to facilities. The impersonation cases in our survey represent members of the media or other individuals who wanted to gain access in order to "see what's going on." However, the medical literature reports a woman falsifying her credentials to a National Guard medical unit operating in St. Bernard Parish in order to gain access to the Parish. She did not provide any direct patient care but did manage to insert herself into several high-level planning meetings and even shook hands with President Bush when he met with medical providers in the Parish.3 Clearly, credentialing during disasters can be somewhat difficult; however, it is also critical in order to avoid patients being harmed by imposters.

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Section References:

  1. The Concept of Operations for the MEMS, ACC, and NECC are available on the Northern New England Metropolitan Medical Response System Web site at: Exit disclaimer icon
  2. Information on the Emergency Systems for Advance Registration of Volunteer Health Professionals is available at: //
  3. Information on the Emergency Management Assistance Compact is available at:

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Patient Selection Tool

As mentioned previously, one potential use of an ACF is for off-loading from hospitals less ill hospital patients who are not yet ready for early discharge from the hospital. The challenge, however, is how to quickly determine which inpatients are eligible for transfer to a designated ACF. To assist in the decision process, a Patient Selection Tool was developed, which is available at (Figure 8). The Patient Selection Tool may be used manually by printing out copies of the tool. Detailed user instructions are included with the tool.

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Equipment and Supply Options

Providing an ACF with the necessary equipment and supplies requires significant advance planning. In most situations, supplies will not be available in large quantities from nearby health care institutions or from normal supply chains. Therefore, supplies must be "cached" in advance for use at the time of the establishment of an ACF. Different levels of supply support have been proposed and implemented.1,2 The following three levels of supply caches are based on their robustness (excluding pharmaceuticals because of their special storage requirements).

Level I: Hospital Augmentation/Limited ACF Cache -- approximately $20,000 (Table 4)

Table 4 is a list of supplies that represents a most basic unit of supply support for increased surge capacity of 50 patients, consisting only of items that have very extended shelf life, such as: cots, linens, masks, gowns, gloves, and IV poles. No pharmaceuticals are included. This material is packed in a trailer for mobility. This cache could be used as additional stocking for an existing hospital (i.e. to set up a medical ward in a cafeteria, using other items as necessary from the hospital) or could offer supplies for a limited level care at an ACF.

Level II: Regional ACF Cache -- approximately $100,000 (Table 5)

Table 5 represents a more complete list of material to supply a regional ACF for 500 patients. This implementation of the cache, or medical armory, concept was developed by the Colorado Department of Public Health and Environment and approved by its Hospital Preparedness Advisory Committee. The approximate price for a single cache for 500 patients is less than $100,000. Note that, as with the Level I cache, pharmaceuticals are excluded and only items with extremely long shelf life are included.

Level III: Comprehensive ACF Cache -- no cost estimate currently available (Tables 6-9)

Tables 6-9 provide comprehensive lists of equipment and consumables that were adapted from work done by the U.S. military and published in The Concept of Operations for the Acute Care Center by the U.S. Army Soldier and Biological Chemical Command (SBCCOM).3 These lists represent a specification for a completely supplied 50-bed ACF consisting of items with both long and short shelf-life. This represents a more complete level of cache than levels 1 and 2. The initial specifications also included pharmaceuticals, but they are not included here as separate national, regional and local planning efforts are addressing this issue.

This extensive list has been separated into: Equipment Considerations, Patient Care Related Consumables, Administrative Consumables and Oxygen and Respiratory-Related Equipment Considerations (Tables 6-9). Note that this equipment and the consumables can be pre-acquired and stored in a "medical cache" as well. Consumable items may represent one of the greatest challenges for establishing an ACF due to the number and quantity of items. This comprehensive list also includes oxygen and respiratory-related supplies that should be considered for providing limited respiratory support.

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Section References:

  1. Rocky Mountain Regional Care Model for Bioterrorist Events: Locate Alternate Care Sites During an Emergency. December 2004. Agency for Healthcare Research and Quality, Rockville, MD. Available at
  2. Hick JL, Hanfling D, Burstein JL, DeAtely C, Barbisch D, Bogdan G, Cantrill S. Healthcare Facility and Community Strategies for Patient Care Surge Capacity. Ann Emerg Med 44:253-61;2004.
  3. Skidmore S, Wall W, Church J. Modular Emergency Medical System Concept of Operation for the Acute Care Center: Mass Casualty Strategy for a Biological Terror Incident, May 2003.

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