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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Chapter 3. Responding to a Disaster
Phases of Response
There are four basic phases of response to a disaster. They are:
- Preparedness (including prevention and planning).
- Actual response to the event.
- Recovery (short- and long-term) and critique.
Although we usually cannot predict disasters, we can control them through
prevention and planning efforts. Prevention through preparedness is probably
the most important phase of response in emergency management. During the preparedness
phase, governments, organizations, and individuals develop plans to save lives,
minimize disaster damage, and enhance disaster response.
Preparedness efforts include:
- Preparedness and evacuation planning.
- Emergency exercises and training.
- Warning systems.
- Emergency communication systems.
- Public information and education.
- Development of resource inventories, personnel contact lists, and mutual
Physicians participate in preparedness and prevention in many different ways,
including: immunization programs, dietary advice, health education, and safety
precautions and planning. As participants in an emergency action plan, physicians
need to help formulate ways of preventing incidents from occurring or limiting
the consequences from an incident that has already occurred. Physicians need
to know what will be expected of their hospital in the case of a potential
infectious disease outbreak. They should also be prepared with the knowledge
and resources needed to help identify the etiology of a problem and to provide
In the case of acts of terrorism, law enforcement plays the lead role in prevention,
although physicians are often called upon to lend their expertise in an effort
to identify the impact that various scenarios would or could have on the health
of the community. Part of prevention consists of participating in a pre-established
medical surveillance network of communities that will alert public health and
safety officials of suspicious trends. A communications network of pediatricians,
school nurses, freestanding pediatric walk-in clinics, and pediatric emergency
departments should be formed.
Medical staffs need to know what will be expected of them and their facilities
in the event of a large-scale infectious disease outbreak. Because of their
unique knowledge base, physicians, especially pediatricians, can be very valuable
sources of information to law enforcement and public health policymakers in
helping to identify and isolate the source of an outbreak and providing guidance
on the need for isolation, quarantine, and treatment.
Planning and prevention are closely related and work hand-in-hand. The people
doing the planning cannot be strangers. It is important that they routinely
and regularly meet and speak with each other to facilitate communication during
a crisis. Communication is a key element for success. If managers cannot communicate
successfully during routine circumstances, they cannot be expected to effectively
communicate during times of crisis.
Plans should be developed and then tested and refined, over and over again.
For a plan to work efficiently and effectively during a crisis, it must be
well rehearsed. Plans that have been tested on a regular basis enable the responders
to know and understand their roles. During a crisis is not the time to find
out that a vital component is missing or nonfunctional.
Response plans must be shared with the people who will be doing the actual responding.
Periodic in-service training should be conducted, including tabletop exercises with
key players and full-scale field exercises. Pediatricians should be proactive
in providing input regarding the unique needs of children during disasters
and ensure that children's issues are included in all preparedness
activities. Lessons learned from either actual responses or from the exercises
and discussions should be incorporated into existing plans and then tested
and evaluated again.
Planners need to ask themselves over and over again: "Are we ready?" Plans
must be constantly changing and evolving to meet changing circumstances, and
no matter how well prepared we think we may be, we can always be more prepared.
Careful review and personal communication with all involved in both incident
management and potential response can always identify more opportunities for
improvement. Because disasters are dynamic events, plans must be flexible so
that they can be adapted to an incident as it develops. People involved in
the planning process should stay current regarding new trends, technologies,
and intelligence information that become available. Planning done in a vacuum
cannot be successful.
Actual Response to the Event
The next phase is the response to the actual event. Response activities provide
emergency assistance for casualties, reduce the probability of secondary damage,
and speed recovery. Response activities include:
- Activating public warning systems.
- Notifying public authorities.
- Mobilizing emergency personnel and equipment.
- Providing emergency medical assistance.
- Manning emergency operation centers.
- Declaring disasters.
- Evacuating the public.
- Mobilizing security forces.
- Providing search and rescue operations.
- Suspending laws on an emergency basis.
Response to a mass casualty incident (MCI) begins at the scene by first responders.
An integral role of the first responder is coordination with agencies able
to recognize characteristics of MCI secondary to bombs or to biological, chemical,
or radiological agents, such that ongoing risk is minimized. First responders
collect casualties, triage survivors, institute treatment (including decontamination),
and transport victims to emergency departments. In blast trauma, first responders
should convey information to hospital personnel so that management of casualties
can be facilitated.
This information should include the sorts of injuries that
are expected, initial estimates of the number of casualties, and any additional
risks to personnel from toxic substances. Involvement of hazardous substances
such as chemical or biological agents, fires, collapsed structures, or the
possibility of a radiation dispersal device (dirty-bomb) should initiate specific
Incidents can be very dynamic, so personnel should be able to adapt plans
to deal with the incident as needed. There should be an incident commander—a
qualified, visible leader—who can take charge of the response and direct
the responders. The incident commander must be able to think quickly, make
rapid assessments, and switch direction as needed without holding a lengthy
caucus. The incident commander should be surrounded by competent, knowledgeable,
and trusted people. They will be called upon to provide complete and accurate
information to the incident commander so that he or she has the tools needed
to make rapid, informed decisions.
The National Incident Management System (NIMS) provides the framework needed to
successfully manage an incident. This is a standardized plan that allows for
flexibility. The NIMS can be used by local, state, and federal authorities to use
resources depending on the nature and the scope of the incident. The NIMS is available
online at http://www.dhs.gov/xlibrary/assets/NIMS-90-web.pdf (PDF Help).
The next phase of response is mitigation, in which actions are taken to stop
the incident from doing any further damage and to stabilize the situation.
Although disasters cannot always be predicted, their consequences often can
be controlled by preparation and planning. Mitigation activities are also important
in the preparedness phase, where they can eliminate or reduce the probability
of a disaster or reduce the impact of unavoidable disasters. The damage done
can be limited or confined using the dynamics of the incident management plan.
Mitigation preparedness measures include:
- Building codes.
- Vulnerability analyses.
- Tax incentives and disincentives.
- Zoning and land use management.
- Building-use regulations.
- Safety codes.
- Sharing of resources among States.
- Preventive health care.
- Public education.
Information resources, data, and services important in mitigation activities include:
- Geographic information systems (GIS)-based risk assessment.
- Claims history data.
- Facility/resource identification.
- Land use/zoning.
- Building code information.
- Modeling/prediction tools for trend and risk analysis.
Recovery and Critique
The recovery phase evolves as steps are taken to mitigate the event. The objective
of recovery is to return things to normal as quickly as possible, and recovery
activities continue until all systems have been returned to normal or better.
Depending on the scope of the incident, the recovery period can range from
hours to years. Damage assessments are made, financial needs are identified,
and timelines and plans are developed and implemented.
Short- and long-term recovery measures include:
- Returning vital life-support systems to minimum operating standards.
- Temporary housing.
- Ongoing medical care.
- Public information, health and safety education.
One aspect of long-term recovery involves assessing the infrastructure,
how it held up during the incident, what the cost of the response was, and
how that cost can be recovered.
Recovery efforts in economic support include:
- Paying out insurance/loans and grants to cover damage.
- Providing disaster unemployment insurance.
- Performing economic impact studies.
Information resources and services related to recovery include:
- Data collection related to rebuilding.
- Claims processing.
- Documentation of lessons learned.
During long-term recovery, participants also review and critique the response,
evaluating how the overall plan worked in a real event, determining what needs
to be done to update the plan and educate responders, and making changes necessary
to improve the original response plan and prevent a recurrence.
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State and Federal
Communication and information sharing are key parts of successful incident
management—both before and during an actual event. Although each area
of the country handles emergency responses in somewhat different ways, all
emergency response agencies use some form of an incident management system.
Almost all use the NIMS with unified command.
Regional physicians should review community emergency response plans, as well as the collaborative efforts between responders and planners designated by pertinent emergency response agencies. Local physicians should become familiar
with the following:
- The response agencies in their area.
- Regional medical, operational, and administration protocols.
- The various levels of training and the roles of all the different responders
in a mass casualty incident, and how these change with the changing situation.
For example, some responders may move victims only after they have been triaged
by other more highly trained responders. In a different scenario, those same
responders may actually move victims before triage because of unstable conditions
(e.g., structural collapse, hazardous materials release). The dynamics of
the incident dictate whether triage or transport is done first.
- Whether the firefighters or police officers in their community are certified
emergency medical technicians (EMTs) or paramedics.
- The person who is in charge of an incident when there is a multi-agency response.
- Where to go for information and to offer assistance during an actual emergency.
- The regional and State emergency planning interface. Each state has its
own unique emergency planning office and incident management system that
ties in with the overall National Response Plan (Figure 3.1).
Emergency Medical Services
The availability and capabilities of emergency medical services (EMS) in the
United States have undergone explosive growth over the last 40 years. The Comprehensive
Emergency Medical Services Systems Act of 1973 established the regional basis
for coordination of emergency medical care throughout the United States. In
addition, the National Highway Traffic Safety Administration (NHTSA) is charged
with coordinating the development of national standard curricula for and education
During the past 25 years, the scope and complexity of care rendered by prehospital
EMS providers have expanded greatly. Four levels of prehospital emergency medical
personnel are currently recognized, in order of increasing skill level with
respect to the care of the trauma patient (Table 3.1).
In recent years, the addition and expansion of initial and continuing education
in prehospital pediatric trauma care (such as that provided by the Pediatric
Emergencies for Prehospital Professionals [PEPP] course of the American
Academy of Pediatrics), as well as the provision of expert pediatric medical
direction, have greatly enhanced the capabilities of most regional EMS systems.
In most regions, injured children can now receive emergency medical assistance
comparable to that of injured adults.
In mass casualty incidents, including those involving release of biological
or chemical agents, both children and adults are likely to be significantly
affected. Children would probably be disproportionately affected by such an
incident, so pediatricians should assist in planning coordinated responses
for local hospitals that may have limited pediatric resources (go to Chapter 1). Health care facilities could also be a primary or secondary target.
At the very least, facilities will be overwhelmed by a massive number of anxious
and worried individuals.
The problems associated with terrorist incidents differ from those usually
faced by hospital disaster alert systems. In the typical scenario, most victims
are triaged in the field and then carefully distributed among available resources,
to avoid a single facility from being overwhelmed. In a terrorist attack, facilities
will be particularly vulnerable to inundation with many victims who have not
been appropriately triaged or transported by EMS. Arrivals without full notification
could interfere with attempts to isolate contaminated victims and ensure protection
of health care personnel.In addition, terrorist events will be further complicated
by the issues of security and forensics.
Hospital emergency department personnel become involved both before and after
the arrival of victims. Activities prior to arrival include processing current
patients in the emergency department to prepare for new arrivals, checking
all equipment, activating additional personnel, assigning team leaders, and
possibly assigning liaisons to government agencies. On arrival of patients,
emergency department staff should ascertain (whenever possible) a victim's
location with respect to detonation, whether a victim was within an enclosed
space or near a body of water, or whether the victim was crushed by debris.
These data provide valuable information as to the degree of injury to expect
in other victims.
Triage is crucial, given the large number of minimally injured and ambulatory
victims presenting to emergency departments after a terrorist incident. The
importance of triage is highlighted by the Oklahoma City experience in April
1995. This explosion caused 759 casualties, of whom 167 died, 83 were hospitalized,
and 509 were treated as outpatients either in an emergency room or by private
Approximately 85% of the 592 survivors sustained non-life-threatening
soft-tissue injuries (including lacerations, abrasions, contusions, and puncture
wounds), and 35% sustained musculoskeletal injuries (including fracture/dislocations
and sprains). The 66 children who were injured in the Oklahoma City blast showed
a similar pattern of soft-tissue and musculoskeletal injury.
The first wave of patients from the Oklahoma City blast arrived either by
ambulance or some other means of transportation within 15 to 30 minutes of
the event. Medical systems were overloaded with minimally injured patients.
As would be expected, hospitals closest to the attack were overwhelmed first.
More seriously ill, non-ambulatory patients tended to arrive later because
of the delay associated with field triage and transport via EMS.
The experience after the World Trade Center attacks in 2001 was similar in that the
vast majority of patients seen in emergency departments were ambulatory and were treated
for minor soft-tissue injuries and released. However, hospital overload was
mitigated somewhat due to the large number of fatalities, which decreased the
number of survivors presenting for treatment. The main lesson to be learned
from these experiences is that casualty profiles are event specific, but an
effective triage system can better direct attention toward the critically ill.
The objective of risk assessment is to estimate the likelihood that an incident
will have an impact on the hospital, as well as the size of that impact. Considerations
in risk assessment include the following:
- Attack has the potential to generate large number of causalities.
- Effects may be immediate or delayed.
- Response will require specialized equipment, procedures (decontamination),
and medications, all adapted to pediatric needs.
- Hospitals may be targets of secondary attacks to amplify effect.
Situations with both high probability and the potential for high impact (e.g.,
an earthquake in California, or a tornado in the Midwest) should receive more
attention in preparedness planning than either situations of low probability
with the potential for high impact (e.g., industrial plant chemical leak) or
situations of high probability and the potential for low impact (e.g., community
outbreak of infectious gastroenteritis).
Hazard vulnerability analysis (HVA) is an aspect of risk analysis that considers
the hospital's capabilities regarding the traditional elements of risk.
This analysis allows a comparison between the potential risk factor (hazard)
and the hospital's ability to cope. The action plan resulting from this
type of risk analysis should be directed toward those hazards against which
the hospital is less able to cope (i.e., vulnerabilities). Areas of vulnerability
may include attack on hospital information systems, inadequate ventilation
systems (negative pressure, contained exhaust) for decontamination procedures
in toxic exposures, hospital staff untrained in the proper use of personal
protective equipment (PPE), and so on.
The key benefit of HVA analysis is the ability to prioritize planning for
the hospital in any given situation. The key to effective HVA is a good, frequently
updated inventory of the resources and capabilities (within both the hospital
and the community) that are available for dealing with a particular hazard-related
Most of our medical systems operate at near capacity in normal times. Pre-event
planning and preparedness are essential to develop local capacity and expand
health care resources to respond to increased needs. Surge capacity should
be created on all levels, including the following:
- Emergency department space.
- Decontamination equipment.
- Antitoxins and medications.
- Hospital bed capacity.
- Extra provider capacity.
- Increased integration back into a community that can provide mental health services.
In general, hospitals should plan to be self-sufficient for the first day
or two after an incident. Most victims in the first 24 hours will be anxious
or worried individuals who may or may not need decontamination before medical
treatment. Assessment of hospital capacity for these victims is essential.
Several teams in small areas can perform triage and rapid treatment. A system
should be established to initially treat victims and then assign them to other
facilities (away from the main site) for definitive treatment. There should
also be followup to ensure that appropriate care is available at the other
facilities. A system should also be established to rotate and supplement staff
for the first 24-48 hours (or longer) until additional medical help can
The following points should be considered in measurement and management of surge capacity:
- Surge capacity expressed in terms of beds is not specific enough. Specific
pediatric surge capacity that is somewhat intervention-specific is preferable.
For example, there may be 1,000 hospital beds available in a large community
but only 10 pediatric intensive care unit beds. If these types of pediatric-specific
resources are needed, the actual surge capacity is only 10 beds.
- Non-disaster-related patients must be cared for in addition to disaster victims.
Surge capacity and overall planning should accommodate both sets of patients.
- Surge capacity and capabilities are determined by many factors (e.g., facilities,
human resources, patients' needs, legal and regulatory issues, policies,
process design, supplies, equipment, etc.). Each factor should be systematically
considered and optimized. A "bottleneck" in any factor can become
the limiting condition. Poor management of these issues can affect outcomes
more than the skill of the health professionals caring for individual patients.
- Assumptions that pediatric patients will be cared for by adult health providers
and facilities are not universally true or necessary in at least some situations.
- Local contexts differ regarding inpatient capacity for high-acuity pediatric
patients. In large urban areas, there are likely multiple pediatric hospitals
within a short distance of each other. They can collaborate and probably
handle patients from all but the largest of disasters. However, many communities
have only one facility that may be a significant distance that is capable
of handling high-acuity pediatric cases. These facilities often operate near
or even above capacity many days each year. So, surge capacity and capability
for pediatric but not adult disaster victims may be critically limited. Transporting
pediatric patients to facilities outside of the region may be beneficial
or even required (particularly if a pediatric facility is damaged or incapacitated).
Pediatricians should educate and advocate regarding this type of planning.
This is similar to the situation for high-end pediatric cardiac surgery,
organ transplantation, and burn unit care for which pediatricians already
refer to resources outside their region.
- The frequent practice of making superheroic efforts at an overwhelmed hospital
needs to be considered against the risk/benefit and outcomes of transferring
patients to hospitals that are not overwhelmed. Generally, pediatric capability
and capacity are available, but they may be at distant facilities.
- Agencies other than hospitals may be needed to care for unaccompanied but
otherwise medically stable children or for children with social but no serious
physical medical issues. This will not occur unless pediatricians help the
responsible agencies prepare in advance.
Protection of Personnel and Levels of Precaution
Hospital staff members are at high risk for secondary exposure from contaminated
victims (e.g., skin, clothing, etc). The Occupational Safety and Health Administration
(OSHA) provides protective standards for hospital response, including:
- A written plan describing how contaminated patients will be managed.
- An Incident Command System described for each type of hazard.
- On-the-spot training and briefing for support personnel, such as physicians.
- A plan for providing exposed employees with medical care and surveillance.
- Training at a first-responder level for employees involved in decontamination
operations, including training in hazard containment and prevention of spread.
Biological agents are generally associated with a delay of hours to days in onset
of illness. Therefore, illness may go unrecognized in the initial stages, which can
result in widespread secondary exposure to others, including health care personnel and
other patients. In this situation, containment of the exposing agents in negative-pressure
environments is mandatory. In contrast, toxins derived from biological agents produce illness
within hours of exposure. The patient exposed to a toxin does not usually pose a significant
threat of secondary exposure to medical personnel, although decontamination may still
be warranted (as in chemical exposure).
PPE includes specifically designed barrier clothing (e.g., gown, boots, and
gloves) to protect the skin and a mask to protect the respiratory tract. Clothing
is designed to provide protection against liquids, vapors, dust, and particles.
Respiratory masks fall into two categories: those that filter the ambient air
to rid it of hazardous particles, and direct-line masks that provide pure air
Chemical weapons are intended to produce immediate discomfort,
incapacitation, or death. Incapacitating chemical agents may be particularly
toxic to small children. The mainstay of decontamination is rinsing with water,
shedding exposed clothing, and in some instances, administering pharmacologic
The risks of contamination are usually recognized at the scene, so that personnel
at the receiving hospital can be alerted. However, hospital personnel are at
particular risk of contamination from exposure, due to the high number of anxious
or worried victims who arrive at the hospital on their own without previous
triage or information on risk factors from the incident scene. Health care
personnel and any adjunct personnel in contact with victims or the hospital
decontamination site should wear full PPE and self-contained breathing apparatus
until the risk of exposure by secondary contamination is completely eliminated.
Equipment used for universal precautions, such as surgical masks and latex
gloves, are inadequate. Recognition of all agents involved in the exposure
and determination of their toxic potential often take time and close coordination
with the regional poison center, the fire department, and the Centers for Disease Control and Prevention (CDC). Hospital
personnel responsible for decontamination and protection should remember the
possibility of more than one agent being used in an assault and also the possibility
of terrorists using a "decoy" agent to mask and delay recognition
of release of a more toxic or lethal agent.
Radiological or nuclear agents are generally associated with a delay in onset
of illness. As with biological agents, illness may go unrecognized
in the early stages, so that the risk of contamination of hospital personnel
by secondary exposure to radiation carried from the scene is significant. Contamination
varies with the emission levels.
PPE for radiological agents includes clothing barriers that prevent radioactive
particles from reaching the skin. Any mask that will prevent dust from reaching
the respiratory tract is protective. Gamma and neutron emitters penetrate clothing
easily and require lead-type barriers. Lead aprons, such as those used for
routine radiology, are not feasible for protection. Some exposure of hospital
personnel may be unavoidable, and in these instances, the radiation exposure
should be monitored and limited to safe doses.
Potential problems with use of PPE include the following:
- Bulky and cumbersome.
- Impedes bending, kneeling to reach small children, infants.
- Impedes nimble use of hands and fingers (needed for starting an intravenous (IV) line,
intubating, drawing up medications, etc.).
- May not be adapted to stethoscope use.
- Poor ventilation and temperature control.
- Profuse sweating, discomfort.
- Potential fluid losses and dehydration.
- Hyperthermia (for personnel working in warm environments [outside tents,
hospital air conditioning system down], or working over-extended hours).
- Unfamiliar "alien" appearance.
- Frightens children.
- Contributes to stress of the crisis.
For additional information on PPE, go to Chapter 5 and Chapter
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Incident Command Systems
Incident command systems (ICS) use a consistent organizational structure
that includes individual positions for overall management of emergency situations.
ICS systems are designed to facilitate interagency coordination(because each
agency has organized their response on the same model). This is one of the
system's most important advantages. ICS can also expand and contract
to meet the needs of the particular emergency situation at hand.
ICS structure is hierarchical. For example, there will be one incident commander,
three key assistants (safety officer, liaison officer, and public information
officer), and four subordinate managers who report directly to the incident
commander (operations, logistics, planning, and finance). Go to http://www.fema.gov/emergency/nims/nims_training.shtm for more information on developing an ICS.
San Mateo County Emergency Services developed their Hospital Emergency Incident
Command System (HEICS) in the 1990s to facilitate earthquake preparedness among
California hospitals. This HEICS provides a useful example of a system
that employs the concept of "unified command," with establishment
of an emergency operations center within the hospital, pre-designed job action
sheets, response activities, lines of communication, and reporting relationships.
The HEICS structure is modeled on the ICS hierarchy. Key participants in the
hospital ICS include the following:
- Hospital chief executive officer.
- Vice president of operations.
- Medical director.
- Emergency manager.
- Community affairs director.
- Critical care manager.
- Emergency department manager
- Hospital communications.
- Facilities and engineering.
For more information on the HEICS, go to http://www.heics.com.
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Regional Coordination of Hospital Response
Emergency incidents also require hospitals to coordinate with community and
medical stakeholders within the regional area. Coordination with community
stakeholders includes liaison and planning with various local, State, and national
agencies/organizations within the region:
- Primary/prehospital/infrastructure Response:
- Police, local environmental protection agency, sheriffs.
- Military (local or regional).
- Regional poison centers.
- Local health department.
- Community/citizen response:
- Schools, public and private.
- Day care units, public and private.
- Service groups (Kiwanis, Rotary, Salvation Army, parent/teacher associations
- Nonsecular groups (churches, synagogues).
- Public recreation administrations (zoos, amusement parks, sports stadiums,
museums, and the like).
Regional coordination with medical stakeholders includes liaison and planning
with various medical entities within the region:
- Children's hospital-based:
- Pediatricians and pediatric subspecialists.
- Pediatric nurse practitioners, physician assistants.
- Ancillary services (nursing, technicians, etc.).
- Air/ground transport services.
- Laboratory services.
- Children's services.
- Support services (dietary, environmental).
- Community-based private practitioners:
- Family practice physicians.
- Emergency medicine physicians.
- Nurse practitioners.
- Physician assistants.
- Other types of physicians and health care providers.
- Community/ regional hospitals:
- Emergency department staff.
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