Disasters often occur without any warning and may result in mass casualties that can overwhelm the capacity of local and regional healthcare systems. The etiology of disasters can be man-made or natural, can be localized or effect a large geographic area, and can result in minimal harm to the population or mass casualties. The most lethal natural disasters include earthquakes, hurricanes, floods, tsunamis, snowstorms, and fires. Man-made disasters include wars, building collapses, mine cave-ins, chemical and biological exposures, nuclear accidents, and civil unrest.
Disasters often occur without any warning and may result in mass casualties that can overwhelm the capacity of local and regional healthcare systems. The etiology of disasters can be man-made or natural, can be localized or effect a large geographic area, and can result in minimal harm to the population or mass casualties. The most lethal natural disasters include earthquakes, hurricanes, floods, tsunamis, snowstorms, and fires. Man-made disasters include wars, building collapses, mine cave-ins, chemical and biological exposures, nuclear accidents, and civil unrest (Figure 15.1 A,B).
Each trauma system and trauma center needs to have a well-rehearsed plan for mass casualty incidents (MCI) for different disaster scenarios (i.e., earthquakes, fires, airport accidents, different types of terrorist attack) that is based on the geographical site and availabilities of resources. A disaster plan should be as simple as possible and should be based on the daily working routine. Knowledge of disaster medicine is paramount to establish a prompt, resourceful, organized response to prevent harm, provide life-saving care, and restore safety to communities.
Epidemiology of Injuries in Mass Disasters
The type and number of casualties depends on multiple factors, including the type of disaster. The Haiti earthquake of 2010 provides an example of the array of conditions produced by such a disaster. Traumatic injuries may include burns, wounds, crush syndrome, traumatic amputations, lacerations, fractures, concussions, and weapon-related injuries. Infectious conditions can develop and include diseases such as cholera, malaria, dengue, hemorrhagic fever, typhoid, measles, tuberculosis, tetanus. Non-infectious and non-traumatic conditions can also be present and commonly include malnutrition, skin disorders, renal failure, pregnancy-related, mental health, and chronic disease complications.
Types of Disasters
A disaster is a natural or man-made event that leads to large scale loss of life, property, and/or infrastructure, which affects a community’s ability to respond. There are a variety of causes of disasters including natural, chemical, biologic, radiation, nuclear, and explosive. Each type of disaster is associated with different injury patterns, risks to patients, and risks to providers, and requires a unique response.
Natural disasters are generally unpredictable. Between 2002–2011, an average of 107,000 deaths and 268 million people per year suffered from natural disasters. Natural disasters may be geophysical, meteorological, hydrological, and climatological. Based on the type of disaster, injury patterns, resource availability, and logistics may vary.
Chemical disasters may result from failures with industrial systems, transportation, waste disposal, and chemical warfare. The Bhopal disaster in India led to the development of material safety data sheets in the United States. Ready availability of these data sheets is required in case of emergency, as they can help provide guidance for decontamination and treatment (Figure 15.2).
Figure 15.2 A building collapse and chemical contaminated area training exercise simulated as part of an earthquake disaster scenario.
Biological disasters are caused by exposures to toxin, micro-organisms, and substance of organic origin resulting in morbidity and mortality. Examples of biological disasters include disease outbreaks, species infestations, and biological warfare agents. Additional biological disasters may coincide with other disasters requiring simultaneous treatment of both traumatic and medical injuries. Biological disasters affecting a large number of people in a locality at a particular time are known as an epidemic (e.g., plague, cholera, Ebola). When an epidemic spreads across larger regions or worldwide, it becomes a pandemic (e.g., H1N1, smallpox, tuberculosis, COVID-19). To prepare for such an event, the Center for Disease Control and Prevention (CDC) in collaboration with the US government has strategically placed stockpiles of medical countermeasures, which can be delivered in a mass causality event.
Radiation and Nuclear Energy Disasters
Nuclear science development has increased the frequency of radiation disasters. These disasters may stem from power generation, nuclear war, medicine, research, or industrial applications. Radiation exposure may lead to localized thermal injuries, systemic injuries, or increasing risk of cancers, infertility, and cataract formation.
Patients may present with contamination from skin, inhalations, ingestions, and absorptions. Symptoms are based on time since exposure and may be helpful for managing patients. Medical care should be promptly addressed by responders trained and prepared in decontamination procedures. Monitoring for radiation can also be achieved by using Geiger counters. However, immediate life-saving procedures should not be delayed for decontamination. Contaminated clothing should be removed and placed in plastic bags with care not to spread contaminants. Once a patient has had their clothing removed and any obvious particles, they no longer pose a threat to the medical team, and standard personal protective equipment (PPE) can be employed.
Radiation accumulates linearly and the US Environmental Protection Agency publishes exposure guidelines for emergency responders. It is important for medical providers to limit their exposure from the source of radiation, both by time and distance. If there is concern, N95 masks should be employed, as ingestion of radioactive particles is the most serious exposure. Furthermore, radiated environments need to be quarantined as radioactive elements may have long half-life’s (Figure 15.3).
Explosive injuries occur in enclosed areas, open areas, or when structures collapse. The speed at which a substance ignites contributes to the degree of injury. The morbidity and mortality from explosions will depend on protective clothing, proximity, quantity of explosive material, physical environment, blast shrapnel, and any intentional contaminants (biologic, chemical, or nuclear). Common explosive injuries include fractures, lacerations, and brain injuries, and can be classified as primary, secondary, tertiary, quaternary, or quinary blast injuries. Additionally, everyone must be aware of the risk of secondary devices, which are additional explosives designed to target first responders, as they attempt to treat victims of the initial explosion (Figure 15.4).
Figure 15.4 Image of the 2013 Boston Marathon Bombing.
The success of a disaster plan depends on the ability of the team to identify who will do well with minimal care, who has nonsurvivable injuries, and those who have severe, but survivable trauma and will benefit from the limited available resources. Effective triage at the scene and again at the hospital is one of the most critical components for the successful management of a mass disaster incident (Figure 15.5).
Disaster triage aims to rapidly identify, register, and assess all potential patients. The goal is rapidly doing the most good for the most people with limited resources. Triage and allocation of resources must take into account the likelihood of benefit, resources required, urgency of condition, and duration of benefit. An ideal system allows for rapid evaluation of patients with set parameters to allow for decisions made based on objective physiologic and observational data.
Triage algorithms classify patients into four categories: ambulatory (green), delayed (yellow), immediate (red), and deceased or expectant (black). Triage tags are often used to help track the classification of patients (Figure 15.6).
While no system has been scientifically validated, various triage methods have been created based on expert consensus. The two most popular systems are the Simple Triage and Rapid Treatment (START) algorithm and the Sort, Assess, Life-Saving interventions, Treatment/Transport (SALT) algorithm. START takes into account walking, breathing, perfusion, and mental status to categorize patients allowing only for airway positioning. Of note, there is a modified version referred to as JumpStart for pediatric patients (0–8 years of age), which accounts for normal pediatric vital signs and allows for five rescue breaths in an apneic patient who still has a peripheral pulse. The SALT algorithm allows for more interventions during the initial triage, including controlling major hemorrhage, opening the airway, two rescue breaths for children, chest decompression, and auto-injector antidote administration.
A much more detailed clinical examination by an experienced physician is needed for a more reliable triage. The triage should take place outside the emergency room and can be performed in conjunction with the trauma team.
Prompt, organized emergency response is paramount in the management of disasters. The initial period after a disaster is critically important to the success of the management operation and can save lives. The biggest failure in disasters and MCIs is failure of communication, so having a preplanned method of sending out alerts and communicating throughout the hospital is key. Additionally, given the low frequencies of these events and providers working outside of their usual environment, frequent drilling regarding roles and provider safety will allow for improved operations.
The incident command system is an organized hierarchical structure capable of command and control over a disaster. The Federal National Incident Management System utilizes the Incident Command System (ICS) to support emergency response personnel during disaster operations. The goal of ICS is to facilitate a consistent response to an incident by using a standardized organizational structure that can be adjusted in a familiar fashion based on the level of need. When multiple agencies are responding to an MCI, common terminology and operating procedures for supervising personnel, facilities, equipment, and communications allows for seamless integration of services.