Introduction
Disasters are large-scale destructive events that disrupt the infrastructure and normal functioning of a community. Disasters are both natural (e.g., earthquakes, tornadoes, hurricanes) and human made (e.g., industrial spills, explosions, structural collapses, terrorist attacks). Such an event presents the medical community with a large number of casualties that require rapid triage and treatment that is disproportionate to the available personnel and resources necessary for optimal care. In addition to events occurring outside of a facility, internal events that could limit a hospital’s ability to deliver services must be considered. Facilities need to be able to identify services such as power and water outages, building compromises, labor disputes, and so on that may limit or threaten operations.
The increase in geopolitical acts of terrorism has changed civilian health care. Providers are now charged with having familiarity with mass casualty situations and must now understand both the pathophysiology and injury patterns produced by chemical, biologic, radiologic, nuclear, and explosive (CBRNE) devices. Civilian caregivers must learn to deliver care in a mass casualty setting with limited or compromised resources, fulfilling the basic mission of minimizing the population’s morbidity and mortality. The bombing at the 2013 Boston Marathon underscores the requirement for increased education of civilians and physicians involved in a response to domestic mass casualty incidents (MCIs).
True MCIs are rare, providing little opportunity for real-time training. No formal components of medical school or residency prepare physicians for the unique demands and approaches required for the medical care of mass casualties. Thus, most medical care providers have limited training and experience in disaster management. Furthermore, disaster preparations in both community hospitals and even trauma centers are often rudimentary at best. However, proper disaster training and planning are nearly universal in their application to actual scenarios. Regardless of the specific event, the elements of an effective disaster response are similar. This allows for an “all-hazards approach” to the development of disaster management principles, which are then easily applied. Well-defined goals of the disaster response and a clearly delineated command structure serve as the basis for efficient and effective recovery from such an event. In addition to true MCI events occurring within the community, hospitals must be aware that their capabilities could be equally challenged should regional diversions or an influx of patients unassociated with an event create a surge of volume that reaches a critical mass. This could be as basic as an influx of stable nursing home patients evacuated after an incident at their facility. The surge of stable patients would stress facility operations and require an immediate response upgrade.
Disaster Planning
Effective planning is paramount to a community’s ability to cope with any disaster. All hospitals and communities need well-rehearsed strategies for disaster management. It is accepted that nearly half of injured survivors from disasters reach hospitals within the first hour and that health care facilities can expect approximately 75% of victims within a 2-hour window. This rapid surge of patients can easily overwhelm hospital staff and resources without prearranged triage algorithms and organizational systems designed for such occurrences.
Disaster plans must have several elements. All levels of acute care providers and administrators should be actively involved in their design to ensure that practical aspects from all phases of the medical response are considered. Prehospital providers, emergency department (ED) nurses, physicians, surgeons, and anesthesiologists who routinely encounter lesser scale casualty situations add invaluable experience to the process. After being drafted, the plan requires the acceptance and endorsement of all involved to create a well-coordinated approach to an expectedly chaotic situation. Because all elements of a disaster cannot be predicted because of the large number of variables, disaster plans are designed to be generic and somewhat flexible. Incorporating common requirements, treatment principles, and expected barriers into disaster plans has been termed an “all-hazards approach.” This eliminates the need for numerous individual plans that quickly become cumbersome and risk adding confusion and inefficiency into the disaster response. It is appropriate for disaster plans to vary by region and even by community, but they must be integrated with local and regional response organizations and facilities to ensure a collaborative approach. Hazard vulnerability analysis (HVA) refers to the formal evaluation of potential disasters with ranking or weighting of scenarios based on their relative probability of occurrence and the severity of impact. Such analysis, although based on both objective historical data and subjective educated projections, provides a basis upon which communities can begin to focus their disaster planning. Thus, hospitals in California may focus preparations on earthquakes, and those in Florida concentrate on the sequelae of hurricanes because these represent probable and highly significant foreseeable disasters. Plans should be based on injuries and lessons learned from previous disasters. Universal organizational schemes are based on predefined leadership positions. Within communities, trauma centers should provide the template for disaster planning because they possess both the staff and resources primed to respond to casualties. Finally, disaster plans are only as effective as the ability of those involved to carry out the objectives. To avoid having a false sense of security in a written plan, hospitals must continually educate staff about disaster care and practice regular disaster drills. The plan’s execution can then become routine and deficiencies remedied while still in a controlled environment. Ideally, each drill is accompanied by debriefing sessions to give feedback from drill organizers to participants and includes a critical revisiting of the plan by all involved. As a requirement of the Homeland Security Exercise and Evaluation Program (HSEEP), all drills and exercises should also be followed up with a comprehensive After Action Report (AAR) archiving the overall performance and response with the goals of creating a corrective action plan to correct any areas needing improvements. Ideally, those corrections should then be integrated into a follow-up exercise to test the efficacy of the changes and make alterations as necessary.
Disaster Classification
Disasters are classified in many ways with each adding to the detailed understanding of the event and its probable impact. This is primarily done by mechanism, with the broad categories of “natural” versus “human-made” events. This division is useful in that each type of disaster will pose unique challenges and produce varied injuries. Natural disasters can be further separated into geophysical events, such as earthquakes, and weather-related events, such as floods. Human-made disasters are subdivided into intentional and unintentional catastrophes.
Disasters are also described by the extent and duration of the event. “Open” and “closed” are accepted terminology for defining disaster extent. Open disasters are devastating for a large geographic area, such as the widespread flooding of the gulf coast after Hurricane Katrina in 2005. Closed disasters generally occur in well-defined and contained locations, such as the bombing of the federal building in Oklahoma City in 1995. Disaster duration is characterized as being “finite” or “ongoing.” Ongoing events do not end abruptly and produce severe prolonged effects and strains on resources. Protracted military conflicts and natural disasters with extensive flooding can be considered ongoing disasters. The loss of infrastructure and increased incidence of postdisaster complications such as disease, starvation, and population displacement characterize ongoing events.
Scope of response, resource consumption, and casualty load are also used to describe mass casualty events. Understanding a disaster’s response and resource requirements may help to accurately depict the disaster’s impact. Classification in this sense has three levels. Level I events require only the use of local resources albeit with some strain on that health care system. These are episodes of multiple casualty events that extend beyond the normal volume of daily trauma. Level II disasters require the mobilization of additional regional assets. Level III disasters necessitate the allocation of large-scale resources, including state, federal, and international organizations.
Disaster Management
Disaster management is broken down into four acknowledged categories: preparedness, response, recovery, and mitigation. Each stage is important in coping with a disaster and in limiting the attendant devastation produced by the event.
Preparedness refers to making a community aware of the circumstances that have the potential for disaster creation (e.g., presence of an aging dam or a nuclear power plant) and planning on how to effectively cope should such an event occur. Plans should be developed to properly address the needs of local facilities before the impact is experienced. Additional tasks such as training personnel, purchasing equipment, engaging in interagency planning, and conducting timely mass casualty exercises must be practiced.
Disaster response encompasses the basic elements of search and rescue, triage and initial stabilization, definitive medical care, and medical evacuation. These steps of the medical response must occur while the global needs for water, food, shelter, sanitation, security, communication, and disease surveillance are also addressed. The actual disaster response is expected to progress through well-defined phases. Initially, chaos predominates while care providers are alerted. Victims are struck with panic and fear. The more distant and less responsive the health care resources, the longer this phase may continue. Minimizing this phase is critical. Chaos is followed by the initial response and organization phase, heralded by the arrival of first responders. To effectively progress, strong leadership and implementation of an organizational framework are required. At this time, the scene is assessed, victims are triaged in the field, and security is established. Although important for all disasters, the principle of ensuring first responders’ safety before rescue efforts commence is especially relevant when facing terrorist attacks. Terrorist tactics include “second-hit” attacks directed at responders. In October 2002, a suicide bomber in Bali, Indonesia, detonated a bomb in a busy business district, attracting people to the location from surrounding buildings. This event was then followed by a hugely destructive vehicle-based explosion in the street that became more lethal given the assembled crowd. First responders were targeted in Atlanta, Georgia, in 1997 when the bombing of a building was followed by an explosive device detonated 1 hour later in the parking lot as emergency personnel worked. This second-hit risk must be remembered when approaching all terrorist targets. Disaster scenes with unstable buildings represent another source of a “second hit,” such as in the New York World Trade Center attacks in 2001 when hundreds of rescuers were lost when the towers collapsed. Additionally, in any explosive event, a high index of suspicion for a “dirty bomb” should be maintained. In these blast situations, an assessment of the safety and the exposure risk of rescue personnel along with the risk of contamination of health care workers and hospital facilities must be considered before rescue efforts are initiated.
First responders must be educated about nuclear, biologic, and chemical (NBC) exposure hazards and understand that sequelae of such exposure may not be immediately apparent. Proceeding cautiously and suspecting potential NBC contamination after a blast are critical. Blasts with known biologic or chemical contaminants require appropriate protective gear for the rescuers to begin the triage efforts. The administration of antidotes may be necessary in some scenarios, but the most appropriate time or place for this to commence (i.e., before or after decontamination or transfer of victims) may be difficult to assess for a given event. After the scene is deemed safe for responders, site-clearing commences with both the decontamination and physical clearing of the disaster scene as well as the transport of casualties to hospitals. Recovery is the last phase and implies a return of normalcy to the area and reconstitution of the damaged infrastructure. This may be relatively rapid in a confined, finite event or may require significant time after a large natural disaster. This phase marks a transition in the focus of disaster response from crisis management toward one of consequence management. Although frequently underemphasized in disaster plans, this phase is essential for the reestablishment of the affected community. During this time, large-scale efforts to permanently replace damaged buildings, revitalize economies, or restore agricultural systems to their full predisaster production capacity are undertaken.
Disaster mitigation refers to the ability to reduce the devastating effects of disasters before the actual event. Tornado warning systems or evacuations before hurricanes are two such examples. Mitigation can occur at any point in the disaster cycle.
Barriers to Effective Disaster Response
In any MCI, a small group of critically injured patients (typically, 5%–25% of the live casualties) will be contained within the larger crowd of less severe casualties. This was well demonstrated in the 1995 Oklahoma City bombing, where of 388 victims who went to local hospitals, only 72 (18.6%) required admission and seven (2%) required intubation. The core mission of a hospital disaster response system is to identify these critical casualties and to provide the requisite level of trauma care that may be acceptable under the circumstances. Failure in this task may result in the misappropriation of valuable resources away from those casualties most in need. Although this task is quite manageable in daily trauma occurrences such as after motor vehicle crashes, mass casualty events add considerable complexity to attaining this goal. A key barrier is any obstacle that threatens this core mission. This includes a lack of warning, inaccessible resources, triage errors, or even a lack of disaster training. Disaster response plans must anticipate and attempt to remove these obstacles in advance in order to achieve success.
The rapid evolution of true mass casualty events poses the first key barrier. Disasters, especially the increasingly prevalent intentional attacks, may provide no warning and little lead time for hospital preparedness. Two corporate bombings in Turkey in 2003 produced 184 casualties for evaluation by a single medical center within the first hour after the incident. This initial surge of patients may also place hospital facilities and personnel at risk for exposure to nuclear, biologic, or chemical toxins. After the sarin gas attacks on the Tokyo subway system in March 1995, hospital workers became victims before the toxin was even suspected. This resulted in contaminated hospitals and fewer caregivers available to provide treatment. Even with a well-rehearsed disaster plan, it takes time to organize a facility into an appropriate disaster response mode and to clear physical space for victim management. When the patient load outpaces the allotment of resources, an exponentially longer amount of time is necessary to restore the balance. Communication is critical in early alerts to allow hospitals the necessary time to decompress their EDs and prepare for the influx.
The timing of disasters can also present significant yet variable barriers. For instance, a daytime mass casualty situation may flood hospitals with victims while resources such as operating rooms (ORs) are in use and therefore are not available for immediate reallocation. Meanwhile, a nighttime MCI may be met by an understaffed response capability until additional assets are made available.
Communications are another consistent source of difficulty during disasters. Whether this equates to cellular phones ceasing to function or emergency lines being inundated with calls, backup plans for communication are critical. This may include dedicated land telephone lines, computer-based systems, or satellite connections. If communication both within and among the response teams (prehospital responders, hospital providers, incident command leaders) fails, then the entire response effort suffers severely. Effective communication also encompasses the relaying of accurate information and proper instruction to the general population through the media. This can reduce panic and the gridlocking of communication and resources of hospitals. Given the requirements of coordination and efficiency in a disaster response, the failure of communications must be prevented at all costs and proper communications for staff updates encouraged.
Another barrier in providing disaster care is human error. Beginning at the scene, less experienced first responders may tend to overtriage, in which case hospital systems will be overburdened with less severely injured patients. With larger MCIs, undertriage may occur because the injury numbers are so vast. At the hospital, the initial wave of casualties will be treated while there may still be limited knowledge about the true nature and scope of the surrounding event. This will cause early errors in resource allocation. Disaster training exercises may help minimize these mistakes because these issues should be identified if the exercise is properly performed and a good After Action Report completed. In addition, casualties often change triage categories throughout the course of the event. For this reason, each casualty must be retriaged at each level, or echelon, of care.
The overall lack of disaster preparedness by health care professionals poses a most formidable barrier. In any community, the majority of physicians are not involved in disaster training and planning, which will hinder an effective disaster response. This is evidenced by several physician surveys. Seventy-two percent (118 of 166) of nonurban physicians in Texas reported no CBRNE training. This mirrored a national survey in which only 21% of physician respondents felt prepared to treat bioterrorism victims. Among trauma surgeons, only 60% understood the Incident Command System (ICS) for disasters, and fewer than 50% of respondents were prepared to manage an exposure to nerve or biologic agents. Even the manual of Advanced Trauma Life Support (ATLS) mentions the basics of blast injury management on only a single page. In addition to being unable to provide exposure-specific treatments, untrained physicians can impede disaster responses by adding to the number of unnecessary people around intake areas without assigned duties or knowledge of mass casualty triage. Now more than ever, it seems appropriate for all members of the health care community to become versed in the language and principles of disaster management.
Disaster Response Organization—Incident Command System
The effective response to any disaster is predicated on the coordination of many individuals, teams, and organizations. This may require concerted efforts by local agencies and medical specialists or involve added dimensions of resources dedicated from geographically distanced areas. To optimize outcomes and maximize communication and efficiency during disasters, the ICS was developed ( Fig. 12-1 ). It provides a modular, scalable, and adaptable organizational hierarchy to manage mass casualty situations. This system of organization has proven to expedite responses in many settings even when a disaster is not being experienced. For hospitals, the responses to census control, unit openings, and other events requiring an organized approach have led to the Hospital Incident Command System (HICS).
Since its inception in the 1970s, the ICS concept has become standard practice as an organizational approach to managing temporary situations by safety professions. In 1981, the ICS provided the basis for the National Interagency ICS Management System (NIIMS), which is the structural backbone for emergency responses by U.S. federal agencies. This design was declared to be the “best practice” standard in 2004 by the Department of Homeland Security, and compliance with the ICS structure is required to receive federal disaster relief.
The ICS structure is built on five major managerial tasks: command, operations, planning, logistics, and finance and administration. These are considered central to managing all disasters, with the size and scope of the situation dictating the number of individuals assigned to complete these tasks. Heading the ICS effort is the incident commander (IC). This individual is ultimately responsible for the entirety of the disaster response. As the ranking official, this person defines objectives, oversees all operations, and delegates responsibility. Up to seven officials will report to the IC.
The safety, public information, and liaison officers are the three officials who constitute the “command staff” and report directly to the IC. The safety officer is charged with assuring that appropriate protection is provided to first responders. With intentional terrorist activity on the rise, this officer must weigh response efforts with the risk of NBC contamination and the chances of a “second hit.” The public information officer is the reference for updated knowledge to the media and public but is also responsible for internal communications to keep staff informed as the event progresses. The liaison officer is tasked with coordinating responses of the potentially numerous agencies and organizations involved and most importantly as the single point of contact for that command section. For HICS, an event-specific fourth position known as the “medical/technical” specialist can be added to the command section. After H1N1, it was observed that the professionals with expertise in epidemiology were not present at the command level. Such an appointment could aid the decisions of the IC during that type of event.
The “general staff” oversee the remaining core aspects of the ICS, including operations, planning, logistics, and finance. These areas are referred to as sections, and the head of each is titled a section chief. The assignment of individuals to these positions and the number of persons within each section depend on the nature and extent of the disaster encountered. In a small-scale event, the IC may personally oversee these additional activities. However, the modularity built into the ICS becomes important in larger disasters when individual section chiefs can be assigned with direct responsibility over teams at their disposal. These chiefs also report directly to the IC (see Fig. 12-1 ).
The planning section chief works in coordination with the IC to develop the designated response. It is this individual’s job to conceptualize an effective strategy to approach the given disaster. Most important, this includes maintaining foresight to anticipate evolving needs and resource depletion. Meanwhile, the logistics section chief must obtain those resources and assets sufficient to perform the planned response. This includes gaining human resources, equipment, and supplies to ensure a sustainable effort. Operation section activities encompass the physical deployment of resources into the field. This includes rescue efforts, securing treatment areas, and the delivery of aid. This section chief is therefore responsible for the actual delivery of care directly to the casualties involved. The finance and administrative section chief should record and analyze the monetary cost of the disaster and the ongoing response. If a declaration of disaster is issued, this role will provide the necessary structure for Federal Emergency Management Agency (FEMA)–related reimbursements that may be very important to economic recovery.
Although the ICS is built on well-defined leadership roles as discussed, the overall function of the ICS depends on several general principles. The more rapidly the ICS is established, the quicker an effective response is mounted. To this end, the terminology, titles, and working procedures are standardized to function in any mass casualty situation. Furthermore, although the specifics of each disaster may dictate the size of the ICS and the expertise of those in charge, the overlying structure of the ICS is constant. The flexibility of the ICS is in its modularity, which permits expansion and contraction of the incident command structure as needed. The key concept dictating this fluctuating size of the ICS is one of a “manageable span of control.” This equates to no one person supervising more than three to seven individuals to maintain the ability to effectively oversee the responsibility of subordinates. An additional means by which the ICS can expand when confronted with a devastating event involving significant interagency efforts is to add a unified command (UC). The UC would be composed of ICs from the primary organizations involved and allow them to coordinate efforts from a central location termed the Emergency Operations Center (EOC). This UC attempts to restore efficiency to situations where jurisdictional or functional roles of agencies overlap. Finally, all individuals involved in the response must perform within this structure. Efforts to operate outside the ICS may lead to confusion and detract from the overall coordination of efforts and reduce efficient utilization of resources.
The ICS structure has also been adapted to provide a mode of operations for hospitals facing disasters. The HICS was originally presented in 1991. This system follows the ICS hierarchy, principles, and structure. Ideally, this same type of organization and distributed responsibility provides the hospital with an effective paradigm to provide organized care to casualties. The only alteration to the ICS structure in the hospital is to modify operation sections into appropriate divisions such as the medical/technical specialist, surgical, medical, intensive, and ambulatory care services. Again, the adaptable nature of this system allows for expansion of the areas most needed while preserving the universal titles and terminology to allow for easy communication with other facilities and with those involved with other phases of the disaster response such as those transporting casualties to the care facilities.
Accidental and Human-Made Disasters
Although both natural and human-made disasters produce significant morbidity and mortality, most of the detailed literature on specific injury mechanisms in mass casualty situations focuses on human-made disasters. In this age of geopolitical instability, much emphasis has been placed on the potential effects of NBC agents. The fact is that blast injury accounts for the preponderance of MCIs ( Fig. 12-2 ). Despite this, there is significantly less awareness among physicians of how to manage blast-related injuries. In a 2004 survey of the members of the Eastern Association for the Surgery of Trauma (EAST), only 73% of the trauma surgeons queried understood the classification and pathophysiology of blast injuries. As explosive munitions become an increasingly common form of civilian attack, it is critical that physicians possess basic knowledge of blast injuries and NBC agents.
Nuclear and Radiologic Events
Nuclear or radiologic material may be dispersed by a detonation of a nuclear device, sabotage or meltdown of a nuclear reactor, explosion of a “dirty bomb,” or a nonexplosive release of radioactive material in a public place. In approaching ionizing radiation exposure, the critical variables are time, distance, and shielding. In these situations, irradiated casualties are not radioactive themselves. Therefore, emergency trauma care may commence with life- and limb-threatening injuries being addressed without delay for radiologic decontamination. About 85% to 90% of external radiologic contamination is easily removed simply by removal of clothing. Skin forms a useful protective barrier, and any decontamination technique that could traumatize the skin should be avoided. However, if open wounds are contaminated, routine débridement and delayed closure is the rule. Radioactive debris should always be removed with instruments, and the surgery may be facilitated by the use of personal dosimeters. After radiation exposure has been verified, the radionuclides involved, amounts, and physical forms must be determined. It is important to be able to assess patients for exposure through the use of radiological detection devices. Without the ability to properly scan for contamination, there is no other alternative than to carry out full decontamination procedures as if they are contaminated.
The time to onset of systemic symptoms is the most important factor in determining whether significant radiation exposure has taken place. Initial symptoms include nausea, vomiting, diarrhea, skin tingling, and central nervous system (CNS) signs. If there are injuries requiring surgery, the procedures are best performed in the initial 48 hours, before exposure-induced bone marrow suppression occurs. If victims remain asymptomatic for 24 hours and show no aberration in complete blood count, particularly the lymphocyte count, they can be safely discharged.
Biological Events
One of the greatest challenges of biological terrorism is the timely identification of its use. As opposed to the overt nature of explosives, biologic weaponry can be deployed covertly without immediate effects to those exposed. Instead, identification may require syndromic surveillance using local or regional health data to identify an outbreak. With the help of the Centers for Disease Control and Prevention (CDC), state and local organizations can collaborate to minimize the time needed for the detection and identification of the pathogen. Rapid biological event recognition is critical to prevent the secondary exposure of the population at large. Monitored system-level activities include school absenteeism, 911 calls, trends in sales of over-the-counter pharmaceuticals, and voluntary reporting by medical groups of apparent trends of illnesses.
The CDC has divided biological threats into groups A, B, and C. The categories are based on the ease of disease transmission, potential mortality and societal health impact, potential for inducing panic and social disruption, and the need for a specialized health response. Category A sample of pathogens with the highest potential for being weaponized are listed in Table 12-1 .
| Agent | Route of Infection | Clinical Signs and Symptoms | Management of Exposure and Treatment |
|---|---|---|---|
| Anthrax: Bacillus anthracis |
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| Botulism: Clostridium botulinum |
| Symptoms begin to show in 6–7 days from impaired acetylcholine release, resulting in cranial nerve deficits, descending skeletal musculature weakness, and paralysis |
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| Viral hemorrhagic fevers: RNA viruses | Highly infectious by aerosol route from animal bites, excrement, insect vectors, and human to human | Fever, myalgias, prostration within 4–21 days, progressing to systemic inflammatory response, petechiae, bleeding, subsequent shock, and death; >50% mortality rate |
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| Plague: Yersinia pestis |
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| Smallpox: variola virus | Highly infectious by aerosol route from human to human | Fever, rigors, headache, back pain, malaise in 7–17 days; vesicular and pustular rash leads to scabs and pitted scars; death occurs as a result of toxemia from viral infection |
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| Tularemia: Francisella tularensis |
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Chemical Events
The use of sarin gas in the Tokyo subway in 1995 demonstrates the potential impact of a chemical attack. The attack, which resulted in the exposure of a number of health care providers to the neurotoxin, reinforces the importance of hospitals taking aggressive measures to preserve and protect their health care facility and resources. The most commonly used chemical agents have traditionally been pulmonary toxins with popularity among terrorists owing to their ready availability, ease of dispersal, significant clinical effects, and proven ability to disrupt and contaminate initial caregivers.
Chemical agents are categorized by their physiologic effects. The five general classes of chemical agents are nerve, blood, pulmonary, blistering (vesicants), and riot control agents. Table 12-2 summarizes the toxicity, mechanisms, clinical signs, and exposure management of common agents.
| Agent | Toxicity and Mechanism | Clinical Signs and Symptoms | Management of Exposure and Treatment |
|---|---|---|---|
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| Chlorine: remove from exposure, respiratory support, no antidote |
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| Riot control agents | Lacrimators (“tear gas”), irritants, vomiting agents | Lacrimation, sneezing, rapid heart rate, respiratory insufficiency | Supportive, self-limiting, resolving within 15 min |
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