Public and Private Agencies

Public EMS systems are often part of the local fire department organization and are more common in large urban counties or cities. This structure developed in the early days of EMS systems as a result of logistic concerns: fire stations were located at tactical points throughout communities and had experience in emergency response. Firefighters could be trained in basic life support (BLS) techniques and thus could function as both fire/safety and emergency medical personnel. Alternatively, public EMS systems may be municipal “third-service” entities that do not fall directly under fire or police organization but may be interconnected with these agencies under a larger public safety institutional structure. Public EMS systems are generally funded through a combination of local taxes, user fees, and patient insurance.

Private EMS systems may be hospital based, locally owned, or subsidiaries of a large national corporation. Depending on the community, these organizations may provide interfacility transfers, as well as respond to local 911 calls. In some areas, private firms constitute the designated first or second responder for all calls and also provide routine transport of nonemergency patients (e.g., scheduled patient trips to dialysis or rehabilitation facilities). Financing generally depends on individual patient insurance and user fees, with occasional government subsidies. Hospital-based systems may be based out of one hospital or a larger hospital organization. If they are under the control of a state or county-run hospital, they may operate under public authority in concert with other safety agencies.

Public-private hybrids are quite common. A local government may contract with one or both types of EMS systems for fulfillment of specified emergency services in a particular region. For example, fire department personnel may be the designated first responders for all 911 calls, but a private or public ambulance may transport all patients from the scene to the hospital. Financing may involve direct patient billing, reimbursement from local government, or a designated fee for services.

Rural and Urban EMS Systems

The design of and challenges faced by EMS systems are often significantly different between rural and urban areas. In general, rural systems developed later than urban ones and are more likely to be staffed with unpaid volunteers.³ These volunteer-based organizations may be public or private and are generally nonprofit entities. Volunteers are usually citizens with outside employment who offer their services on an unpaid basis for emergency response, training, and community education. Funding is largely through taxes and municipal support, although private donations and fund-raising are often necessary. Volunteer EMS systems face many challenges that are representative of rural systems as a whole, namely, high cost to cover large geographic areas with few citizens, high response times, lower levels of training, and relatively low patient volumes.^10,11 Urban EMS systems have their own distinct set of difficulties, among them high patient volumes, traffic congestion, and limited resources.

Evidence suggests that rural emergency morbidity and mortality is significantly greater than that for comparable urban patients. Reasons for this difference include longer response and scene times, lower patient volumes, and less overall training for first responders.^12–15 Technologic advances such as “E911” (enhanced 911) show some promise in significantly reducing emergency responders’ transport time to the scene.¹⁶ Adapting specific on-scene protocols and increasing access to high-quality medical care (prehospital and in-hospital) in rural areas have also been suggested as possibilities to decrease the gap in rural-urban adverse outcomes.¹⁵

Single-Tiered and Multitiered Systems

EMS systems are further divided by hierarchic types. In single-tiered systems, all dispatched calls are serviced by a single level of first responder and vehicle. In contrast, multitiered systems have variable types and levels of personnel, equipment, and vehicles available for response. A typical multitiered model includes both “first responders”—police or fire department personnel who are strategically geographically located throughout the area—and a second-tier response of more skilled paramedics and EMS personnel. First responders generally have limited training in BLS techniques such as lifesaving airway maneuvers, hemorrhage control efforts, and cardiopulmonary resuscitation (CPR). The second-tier response can usually provide advanced emergency techniques and transport to the hospital.

In addition to the basic first-response, advanced transport system just described, other multitiered EMS designs may be used. Examples include police or fire first response with private ambulance transport, ground first response with air transport, BLS transport with an ALS intercept vehicle as needed, and separate ALS response and transport vehicles. All systems are designed, in theory, to minimize EMS response, scene, and transport time while providing the highest possible quality of patient care.

Dispatch and Medical Control

In the United States, 99% of the population has access to 911 for emergency calls.⁷ Most dispatch centers use E911, a system whereby the caller’s location is shown on the dispatch operator’s screen. Formal training for 911 dispatch personnel exists, and national guidelines that advocate for certification standards have been established.¹⁷ There is a trend toward consolidation of all emergency calls into one 911 center, where dispatchers take calls and then directly relay information to the appropriate EMS or public safety agency. Dispatch actions and instructions may be shaped by established guidelines that allow adaptation to the situation at hand or by more rigid protocols that detail a specific plan of action. Some agencies may rely on computerized algorithms to assist dispatch; a controlled trial of British nonurgent emergency calls found that using a computerized decision tool plus either nurse or paramedic input resulted in more than half the calls triaged as not needing an emergency ambulance. However, only 20% of these callers chose to cancel the ambulance, and this group had similar hospital admission rates as those triaged as needing emergency transport.¹⁸

EMS systems rely heavily on both online (direct) and off-line (indirect) medical control. Physician involvement in EMS medical control developed as physicians spent less time directly in the field and paramedics increased their training and ability to act as physician surrogates. Every EMS system is headed by a medical director, a physician with or without specialty training who has direct authority over operation of the system, performance of emergency personnel, and patient care. Standardized guidelines and requirements for EMS medical direction have been published by the American College of Emergency Physicians (ACEP).^19,20

Online medical direction involves direct communication about patient care between on-scene emergency responders and the EMS medical director or a designated representative. Depending on the region, online medical control may be provided by a single centralized facility (base station) such that all calls requiring medical control—regardless of their destination—are handled by one institution. In other areas, each receiving hospital may have its own medical control and handle calls specifically directed toward that facility. The personnel responsible for direct medical control must be knowledgeable about specific protocols or regional system capabilities to provide accurate information about patient care in the field and appropriate transport.

The evidence basis for improved patient outcomes with online medical control is mixed. It has been shown to significantly increase on-scene time, and orders given rarely deviate from existing protocols.^21–23 However, there is some evidence that online medical direction may decrease the use of inappropriate resources while preserving outcomes in some patients.²⁴ The greatest benefits of online direction may be in resolving difficult ethical or medicolegal situations on scene and in notifying receiving hospitals of incoming critical patients so that resources can be assembled and are ready before arrival of the patient.

Off-line medical direction refers to written protocols that guide common patient interactions, as well as continuing education and quality assurance initiatives. EMS systems have specific protocols for commonly encountered situations that, ideally, should improve patient outcomes and reduce time at the scene. Protocols should be developed on the basis of patient history, mechanism of injury, physiologic characteristics, local hospital capability, and transport times. Medical directors should be active in developing and implementing protocols, as well as in training responders in their application and quality evaluation of patient records.²⁵ Research indicates that use of well-developed standing protocols significantly reduces on-scene time and decreases inappropriate treatment in the field.²⁶ Furthermore, diagnostic accuracy plus agreement with physician assessment of patients is generally high.²⁷

EMS Responder Personnel

Before the National Academy of Sciences paper on trauma in the 1960s, few standardized training programs existed for EMS personnel. Subsequent creation of the Department of Transportation resulted in a formalized 70-hour curriculum for basic EMT certification. Passage of the EMS Systems Act of 1973 provided millions of dollars for EMS training, equipment, and research and identified basic elements that must be included in all EMS systems (Fig. 215.1).²⁸ However, until recently, heterogeneity of regional systems persisted such that a 1996 survey identified more than 40 different types of EMS personnel certification across the country.²⁹

Fig. 215.1 Functions and personnel of emergency medical services.

In general, EMS personnel are categorized into four skill levels: first responders, EMT-basic (EMT-B), EMT-intermediate (EMT-I), and EMT-paramedic (EMT-P). First responders undergo roughly 50 hours of training in basic first aid, CPR, uncomplicated obstetric delivery, simple wound and fracture care, and use of automated external defibrillators (AEDs). EMT-B personnel receive first-responder training plus an additional 50 to 60 hours of education in triage, extrication, transfer, oxygen and self-medication assistance, and possibly advanced airway techniques. Most U.S. ambulances are staffed with at least one EMT-B. EMT-I requirements often vary by state but generally include intravenous access and monitoring and possibly advanced airway and life support measures. EMT-Ps undergo EMT-B training plus at least 250 to 500 additional hours of education, including in-hospital experience. They are skilled in advanced airway and life support techniques, vascular access, monitoring, and administration of medication per local protocols.

Recognition of the wide regional variation in training standards and skill levels led to development of the National Highway Traffic Safety Administration National EMS Scope of Practice Model in 2005. This consensus document promotes national standardization in training and education to improve consistency within and among agencies, increase public understanding of EMS roles, and move toward a coordinated national EMS system.⁹ The model advocates four separate and sequential levels of certification—emergency medical responder, EMT, advanced EMT, and paramedic—and clearly defines minimum educational levels and skill sets for each. Most states have already implemented or are in the process of testing these national guidelines for local use.

There is some evidence basis for the current multilevel EMS personnel system. Early EMS research found a significant reduction in mortality from cardiac arrest with the use of paramedic responder crews versus EMT-Bs.^30,31 Outcomes in trauma have also been shown to improve significantly when ALS-capable ambulances are on scene as compared with BLS personnel.^32,33 However, other studies evaluating paramedic- and non–paramedic-containing crews found mixed results. In general, on-scene time is significantly longer for crews in which one or all of the responders are paramedics.^34,35 Paramedic crews had higher skill levels and provided more on-scene interventions, but some authors suggest that their presence on every ambulance may not be warranted.³⁶

Air Medicine Transport

Although a full description of air ambulance systems is beyond the scope of this chapter, this method of transportation plays a crucial role in the transport and transfer of critically ill patients. Ground emergency transport remains the mainstay of prehospital transport and transfer; however, air medical services can have a significant impact on patient care in selected conditions.^37,38 The benefits of air ambulance transport are largely attributed to increased speed and higher crew skill levels; however, safety, cost, and limited evidence to support improved outcomes are major concerns.

The literature on selected prehospital air transport focuses largely on trauma patients and presents mixed evidence for its use. Retrospective evaluations of trauma patients have shown a significant decrease in mortality with helicopter transport^39,40; however, several studies have found no difference in patient outcomes for both trauma and nontrauma conditions^36–38 and that air transport is overused and costly.^40–44 Criteria for air transport can vary widely by EMS system, and overtriaging is common.⁴⁵

The National Association of EMS Physicians has published guidelines regarding the use of various methods of air transport, as well as which patients are most likely to benefit from its use. In general, helicopters are best used for transport involving a shorter distance (less than 100 miles) but are subject to weather concerns. Fixed-wing aircraft are preferable for distances greater than 100 miles and are less dependent on inclement weather, but they must land at airports (thereby prolonging transport time). Severely injured trauma patients at some distance from a regional trauma center are most likely to benefit from air transport or transfer; critically ill nontrauma, cardiac, pediatric, and possibly obstetric patients may also have improved outcomes in selected situations.⁴⁶

The safety of both patients and medical staff is a prominent issue in air medical transport. As the number of flights has increased in recent years, so has the number of aircraft accidents. Between 2002 and 2005, 55 crashes occurred and resulted in 54 fatalities; the incidence of aircraft accidents per number of flights increased as well.⁴⁷ Patient safety in flight is also of concern; an estimated 5% of patients suffer a “critical event” (decompensation or deterioration) during transport.⁴⁵ Factors such as weather, time of the day, terrain, communication difficulties, and medical crew training have been found to be associated with adverse events, but more study is needed to improve air transport safety.

Cardiovascular Emergencies

Some of the earliest organized EMS research focused on cardiac arrest and early CPR and defibrillation. A 20-year review of EMS systems in 29 cities found that systems with a single emergency responder were associated with lower rates of survival of patients in cardiac arrest than were two-responder (EMT and paramedic) systems, largely because of early CPR in the latter.⁴⁸ Time to defibrillation has consistently been found to improve outcomes after cardiac arrest.^49,50 A 25-year retrospective review of cardiac arrest with EMS intervention found that survival rates remained unchanged; however, the authors suggested that improvements in EMS delivery, such as dispatcher-assisted bystander CPR and early defibrillation, balanced the adverse temporal trends that would otherwise have increased mortality rates.⁵¹ New life support guidelines emphasize the role of EMS dispatch in instructing hands-only CPR to bystanders and widespread use of AEDs, both of which are considered to be an important adjunct to trained EMS response.^52,53

Prehospital Resuscitative Interventions

Advanced resuscitative techniques, such as endotracheal intubation and intravenous fluid administration, are frequently performed by skilled paramedics on critically ill patients. Common thinking has been that earlier intervention should improve outcomes; however, solid evidence supporting prehospital intubation is lacking. Although studies are most frequently observational, the literature available suggests that EMS intubation does not improve morbidity and mortality and may in some cases worsen patient outcomes.^47,54 Similarly, a recent large multicenter study found that prehospital intravenous fluid administration was associated with increased mortality in nearly all subsets of trauma patients, particularly those with penetrating trauma, hypotension, and severe head injury.⁵⁵ This evidence indicates that a “less is more” or “scoop and run” approach to EMS transport may be safer for patients.

Trauma

Much research on EMS response to trauma focuses on response times and the perceived benefit of “regionalization” of trauma care—that is, linking prehospital systems with participating hospitals, public health agencies, and other care providers within a certain region to achieve optimal system efficiency and outcomes.⁵⁶ Regional systems generally have specific protocols governing EMS responder actions and transport to specialized trauma centers when appropriate. Even though patients transported directly to designated trauma centers in lieu of the closest facility have more critical injuries, mortality generally remains low, largely because of decreased prehospital time until direct transfer to the specialty hospital.⁵⁷

Despite the advantages of regionalization, the effect of EMS transport to a trauma center may not always be significant. Some evidence suggests that critically ill patients transported to a trauma center by EMS arrive at the hospital significantly faster than did patients in private vehicles but have no significant improvement in mortality rates, complications, or length of stay.⁵⁸

Response Time

EMS response time is often used as a benchmark of overall system performance, with accepted standards of 4 minutes for BLS and 8 minutes for ALS arrival.⁵⁹ Specifically, national guidelines recommend medical intervention within 4 to 6 minutes of EMS activation for patients in cardiac or respiratory arrest, although such intervention may include dispatcher-assisted bystander CPR or AED use.⁶⁰ Studies of set response time criteria have shown mixed results. Retrospective and post hoc analyses of urban EMS transport show a possible survival benefit for patients transported to hospitals in 4 minutes or less, although the advantage was not significant for those not in cardiac arrest.^59,61 E911 systems—in which caller location is available instantly—can decrease response times because they help plan more direct routes to the scene and reduce the likelihood of ambulance crews becoming lost.¹⁶ Furthermore, response times should be targeted to specific regional needs and may be maximized by a strong community-wide first-responder presence, strategic placement of ambulances based on historical call data, mobile mapping or global positioning systems, and adequate fleet maintenance.^5,61

From their earliest beginnings as purely military organizations to the complex heterogeneous models in place today, EMS systems have evolved into critical providers of health care and a critical component of modern emergency medicine. In 2010, EMS was approved by the American Board of Medical Specialties as the sixth subspecialty of emergency medicine, with development of standard examination and certification procedures underway. This further solidifies EMS as a distinct clinical subspecialty involving the prehospital care of sick and injured patients, regardless of specific local or regional system design.

Introduction and History

Disaster medicine can be defined as “a sudden and extraordinary misfortune that overwhelms the immediate ability to manage or compensate.”² Increasing attention has been focused on this nascent medical specialty in recent years with such high-profile disasters as the September 11, 2001, terrorist attacks and severe natural disasters such as hurricanes, earthquakes, and tsunamis. With each successive disaster and its medical and public health response, more is learned and planning can be refined for the next event.

Although the existence of apathy toward disaster planning (and resource allocation toward this end) is well documented,^62,63 major and minor disasters occur with regular and increasing frequency. In the past hundred years, millions of lives have been lost internationally from natural disasters. In 2005, Hurricane Katrina–related flooding was responsible for more than 1500 fatalities along the U.S. Gulf Coast. Worldwide, flooding of the Yangtze River in China caused 3 million casualties in 1931, deaths from the Indian Ocean tsunami in 2004 approached 300,000, and the devastating 2010 Haiti earthquake killed more than 230,000 and displaced up to an additional 2 million. Over the years, earthquakes, landslides, volcano eruptions, and massive fires have resulted in staggering economic losses, population displacement, disease, and death. Research suggests that losses from natural disasters are probably only going to rise because of growing population density (particularly in high-risk areas) and increased hazards as a result of rapidly expanding technology (i.e., transportation of more dangerous materials, fire threats in high-rise buildings, vulnerable financial and economic infrastructure).⁶²

Despite the clear threats from natural disasters, much of the focus of disaster medicine in recent years has been placed on intentional, man-made events—namely, terrorism and mass casualty incidents. Even before the devastating terrorist attacks on New York City in 2001, researchers predicted that the probability of exactly such an event was extremely high.⁶⁴ Despite performing a mass casualty drill just 3 days before September 11, none of the existing protocols or triage systems proved adequate for the resulting event.⁶⁵ Subsequent creation of the Department of Homeland Security (DHS) has provided federal agency support for and focus on expanded research into and development of all aspects of disaster planning for man-made incidents.

Definitions and Classifications

In general, disasters are classified by their relationship to the hospital setting, inciting event (natural or man-made), and the anticipated necessary response. Internal events occur solely within a particular hospital or medical center (e.g., power outage, building collapse), whereas external events involve some part of the larger community. This system is most useful in preparing the facility to either receive patients from outside or deal with internal problems; however, many disasters have both internal and external effects, and such a narrow classification scheme is not easily applicable to a variety of situations. In terms of anticipated response, most disasters are classified into one of three categories. Level I disasters are those in which local emergency response teams and organizations are adequate to manage the event alone. Level II incidents require a regional approach and mutual aid from surrounding areas. Level III events overwhelm local and regional efforts and require state or federal support.⁶³

Disaster Planning

Although The Joint Commission (TJC) requires all health care facilities to conduct two disaster drills per year, disaster planning is rarely emphasized or sufficient. Many factors contribute to the inadequacy of most hospital or regional disaster plans, namely, the unexpected and sudden nature of most events (thus making prospective evaluation impossible), poor record keeping, faulty assumptions on which significant parts of the plan are based, and failure of communication and command structures.⁶⁶ For disaster plans to be effective, they must be based on valid assumptions of what may occur in a variety of event settings. Furthermore, the planning process must include all systems and organizations that will be affected by the disaster and have a role in its aftermath, and all parties must have a working knowledge of the plan, the chain of command, and their role in it.⁶²

Critical to the development of an appropriate plan is a hazards analysis of particular events to which a hospital or region is most susceptible. In this manner, organizations can plan effectively for the types of disasters that they are most likely to experience. A standard tool for evaluating hospitals’ disaster plans is available through the Agency for Healthcare Research and Quality.⁶⁷ Frequent rehearsals of disaster plans are of utmost importance. A written plan is useless unless it is thoroughly understood and practiced by all parties involved.⁶² Rehearsals should be varied and include single-agency drills, tabletop exercises with participating community organizations, functional experiences with state and local emergency operations centers, and a full-scale interagency real-time drill. The latter should be as realistic as possible, with mock patients, evolving scenarios, and full community-wide participation. Equally important to any disaster plan is the “afteraction”—discussion of the drill or real-life event with a focus on identification and rectification of problems and appropriate refinement of the plan.⁶⁸

A good disaster plan should cover both internal agency and external community needs and focus on all phases of the inciting event: prodrome/mitigation, impact, rescue, and recovery.^2,63 Interhospital plans should involve all departments responsible for patient care and infrastructure and detail clear policies related to the chain of command and physical control centers, communication and public relations, record keeping, personnel needs, and equipment and resource supply. External planning should involve all local agencies responsible for protection and care of citizens. The Incident Command Structure (ICS) provides a means to delineate a clear chain of command and management structure during critical events. Developed after a series of devastating California wildfires in the 1970s, this model provides for an overall incident commander of any disaster event who oversees predesignated public relations, logistics, finance, supply, and organizational section chiefs. Each section has a variety of personnel with specific duties and areas of focus who report to the chiefs at regular intervals. The ICS is frequently revised and is designed to be flexible, predictable, and accountable, with improved documentation, common language, and cost efficiency.⁶⁹

Disaster Response

Response to a catastrophic event requires rapid mobilization and efficient use of available resources. Clear and defined roles should be established for prehospital providers, health care facilities, and all levels of governmental agencies involved in public safety and welfare. The usual standard of medical care may not be possible or desirable in the acute postdisaster period, and alterations in practice will probably be necessary, within accepted boundaries.⁷⁰

Prehospital Disaster Response and Triage

Though fully capable of responding to individual emergency calls, most local EMS systems are often not able to respond adequately to a widespread or overwhelming event.⁷¹ The concept of prehospital triage, used routinely by EMS, is of utmost importance in managing disasters. Unlike routine triage—where the aim is to identify those few critically ill patients who require immediate, aggressive resource utilization—disaster triage attempts to “do the most good for the most people” and often requires that seriously injured victims receive little to no immediate care. Disaster triage models attempt to rapidly identify individuals who will benefit most from immediate stabilization with the least amount of available resources.

The simplest method of triage assigns each patient a color-coded tag with frequent opportunities for reassessment (Fig. 215.2). Green tags are given to patients who require minor, nonimmediate medical intervention. Yellow tags indicate potentially serious injuries, but ones that are relatively stable and can wait a short period. Red tags designate patients who have life-threatening, but potentially treatable injuries that require immediate medical care. Black tags signify dead or critically ill patients who will not survive without significant use of resources and time unavailable under disaster conditions. For example, an apneic victim of a large-scale blast injury with significant head and abdominal injuries may be tagged “black” because the immediate resuscitative and stabilization needs of the victim would require an inordinate use of personnel and equipment given the number of victims and likelihood of a meaningful outcome.

Fig. 215.2 Example of a simple disaster triage tag.

Tag systems are combined with triage models to provide specific algorithms for classification of patients. Widely used in the United States, the START (Simple Triage and Rapid Assessment) system triages mass casualty patients by several simple variables: breathing, ambulation, radial pulse, and ability to follow commands (Fig. 215.3). Patients are categorized as “green” if they are initially ambulatory with minor injuries. “Yellow” victims are those who may be unable to walk but are breathing with respiratory rates lower than 30 breaths/min, are well perfused (capillary refill longer than 2 seconds), and can follow simple commands. Patients with respiratory rates higher than 30 (with or without airway positioning), delayed capillary refill, or inability to follow simple commands are tagged as “red,” and the need for immediate lifesaving attention is assessed. Apneic patients are tagged as “black,” and no further interventions are performed. Refinement of this model has led to specific, but still simple modifications for pediatric patients.⁷²

Fig. 215.3 Combined START (Simple Triage and Rapid Treatment)/JumpSTART triage algorithm.

*When using the JumpSTART algorithm, first evaluate all children who did not walk under their own power. A, Alert; CR, capillary refill time (seconds); Delayed, treatment may be delayed for hours to days; Immediate, requires immediate lifesaving treatment; JS, JumpSTART; P, pain; Pedi, pediatric (patient); U, unresponsive; V, voice.

The SAVE (Secondary Assessment of Victim Endpoint) model was developed as an adjunct to the START system. After primary assessment with START, secondary triage is performed with SAVE to assess the following: prognosis if only minimal treatment is performed and prognosis with just the available resources on site or at the disaster medical aid center. Patients are sent to a treatment area only if treatment will reduce morbidity or mortality within the delayed time to definitive care without consuming a disproportionate amount of resources.⁷³ The SAVE protocol provides specific guidelines based on age, injury location (head, extremity, spine, chest, and abdomen), and type of injury (burns, crush injuries, blunt or penetrating trauma) and suggests treatment priorities in order of likelihood of success (Box 215.1).

Box 215.1

Secondary Assessment of Victim Endpoint Protocol Treatment Priorities (in Descending Order)

Temporary airway management

Pressure dressings to stop bleeding

Simple pneumothorax

Treatment of shock after control of bleeding

Advanced airway techniques

Limb manipulation for vascular supply

Burns—25% mortality

Chest trauma

Spinal injury

Fasciotomies, amputations

Open wound care, closure

Head injury; GCS score ≥ 8

Abdominal trauma

Head injury; GCS score < 8

Burns—50% mortality

Burns—75% mortality

Head injury; GCS score 3

GCS, Glasgow Coma Scale.

From Benson M, Koenig KL, Schultz CH. Disaster triage: START, then SAVE—a new method of dynamic triage for victims of a catastrophic earthquake. Prehosp Disaster Med 1996;11:117–24.

The START system has been shown to have high sensitivity, be quick to administer, and easily be taught to first responders.^74,75 However, real-time use of the START system during the terrorist attacks in New York City in 2001 proved ineffective. Because of the dynamic nature of the event, the loss of communications, and the fact that rescue personnel were in personal danger, the START system was abandoned.⁶⁵ International triage systems (Careflight, Triage Save, and Sort) are comparable with START in prediction of critical injury,⁷⁶ but currently no national triage guideline exists. The SALT (sort, assess, lifesaving intervention, treatment/transport) model was developed by a multidisciplinary panel of disaster experts to provide such a national standard.⁷⁴ This model includes anatomic and physiologic considerations, as well as assessment of available resources (Fig. 215.4).

Fig. 215.4 Proposed SALT (sort, assess, lifesaving intervention, treatment/transport) mass casualty incident national triage guidelines.

(Adapted from Lerner EB, Schwartz RB, Coule PL, et al. Mass casualty triage: an evaluation of the data and development of a proposed national guideline. Disast Med Public Health Prep 2008;2(Suppl 1):S25–34. Available at http://www.dmphp.org/content/vol2/Supplement_1/images/medium/7FF1.gif).

Weapons of Mass Destruction and Hazardous Materials

Traditional disaster medicine developed mainly in response to natural events such as floods, earthquakes, tornadoes, and other disasters. However, increasing sophistication and spread of man-made disasters in recent years have brought these types of catastrophic incidents to the forefront of focus and research. Potential agents available to terrorists include chemical, biologic, nuclear, radiologic, and explosive devices (generally referred to as weapons of mass destruction [WMD]); although the overall likelihood of an attack is low, the consequences may be cataclysmic. One gram of botulin toxin has the potential to kill 1 million people,⁷⁹ and the effects of nuclear and radioactive agents can reach across continents. The response to WMD events may differ significantly from the traditional disaster models described earlier, with shifting priority on decontamination, agent-specific triage, and special resources and personnel.

Preparing for biologic and chemical attacks is difficult and must be adaptive. Disease surveillance programs that link a community are essential for detection and prompt response because biologic agents may not be detected for days to weeks.^80,81 Predisaster emphasis should be on hazard analysis, as well as training and stockpiling of antidotes for the most likely agents to be used. The Strategic National Stockpile is a national reserve of medical supplies, antidotes, and medications managed by the Centers for Disease Control and Prevention and strategically placed in states for rapid availability following a mass casualty event.

In both biologic and chemical attacks, early evacuation and containment of the “hot zone” (the area of maximum contamination) is critical to mitigate injuries and spread. The hot zone should have a clear and strict entry and exit, separate “clean” and “dirty” areas, and continuous monitoring. Primary emphasis should be given to decontamination and safety of first-responder personnel, not only to ensure a strong medical response but also to limit unintentional dissemination of the contaminant. Accurate risk assessments should be communicated to the public and updated frequently.

Traditionally, preparation for WMD has used the more common hazardous materials (HAZMAT) exposure training methods. These models may not, however, be appropriate.^64,82 HAZMAT events assume an exposure away from health care facilities, where response teams with maximum personal protection and extensive decontamination equipment work to rescue and decontaminate small numbers of victims. Large-scale exposure to WMD may encompass public areas and health care facilities, thereby compromising response efforts and calling into question the traditional decontamination methods.⁸³ For example, in the 1995 Japanese subway nerve gas attacks, several thousand people were potentially exposed, yet fewer than 100 were killed or seriously injured. However, thousands arrived at hospitals by private vehicle without on-scene decontamination, which quickly overwhelmed the facilities and potentially exposed scores of essential medical personnel.⁸⁰

The Role of Emergency Physicians in Disaster Medicine

Published ACEP policy advocates a leadership role for emergency physicians in all aspects of disaster research, planning, and implementation.⁸⁴ The traditional focus of disaster medicine—to do the most good for the greatest number of people—may seem to be at odds with the traditional emergency medical principles of aggressive resource utilization for selected critically ill patients. However, the emergency physician is generally the best-trained individual to coordinate medical control, supervise triage, connect with other municipal and public health agencies, and oversee direct patient care during a catastrophic event. Several formal disaster medicine fellowships exist for emergency medical physicians, and disaster training is included in the emergency medical residency curriculum. Advances in research and increased global attention to natural and man-made disasters create exciting potential for emergency physicians to lead the development of disaster medicine as a discipline.