A mass casualty incident (MCI) is an event that produces or has the potential to produce multiple casualties requiring medical care. The goal of prehospital care is to provide the optimal level of care to save the most lives and minimize the morbidity of this type of event. For the purposes of this chapter, we will further define the term mass casualty as an event that challenges the everyday response capacity of a local response system requiring a change in mode of operation. This chapter will attempt to distill the essential elements of prehospital mass casualty management and planning.

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  Describe essential elements in planning for response to mass casualty.

  
  
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  Describe on-scene responsibilities of EMS assets during a mass casualty response.

  
  
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  Discuss the importance of patient tracking.

  
  
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  Detail the role of EMS medical director during mass casualty management.

  
  
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  Discuss some challenges of a multiagency response.

  
  
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  Discuss prearranged roles of area hospitals and health care facilities during a mass casualty.

  
  
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  List community and volunteer organizations that can expand the ability to care for patients during a mass casualty disaster.

PLANNING

The planning phase of disaster preparedness is essential to mass casualty resource management. The development of response protocols for EMS, identification of emergency response capabilities, activation of the disaster response system, and regional/local interagency planning will create the framework for an effective response.^1–3 Prehospital medical care requires cooperation and coordination with many partners including government, hospital, and community resources.⁴ Many communities perform hazard analysis to identify common and catastrophic scenarios that must be prepared for. Understanding the roles, responsibilities, and capabilities of each community, state and federal partner will promote a more efficient response.

EMS MASS CASUALTY MANAGEMENT TRAINING

EMS providers should be trained in the implementation of mass casualty scene management and incident command.⁵ In fact, it is a requirement that first response agencies that receive federal funding are trained in Incident Command Systems (ICS) and National Incident Management Systems (NIMS). ICS, NIMS, and the federal response to disaster are all discussed in details in other chapters; however, it is important to mention here that the ability to have an interoperable, scalable response will allow the rapid incorporation of additional resources into a response effort that traverses local jurisdictions or requires a state or federal involvement.

DRILLS AND EXERCISES

Exercises are an essential step in the planning process. All components of a plan should be exercised, and then the interface for those individual components should be assessed in tabletop and full-scale exercises. Such exercises not only promote familiarization with the plans for all involved, but also identify deficiencies or areas for improvement. Subsequently the plans must undergo revisions and be reexercised. Therefore, the planning process may require less effort after initially developed, but remains a continuous cycle of evaluation and modification.⁶

Municipalities and states deal regularly with minor mass casualties, most of which do not impact the daily operations of EMS agencies. However, the principles of MCI management apply and these events can prove to be excellent trials for larger events. After-action reports should detail lessons learned and action plans to improve response.

MCI RECOGNITION AND ALERT

Plans must first take into account the process for notification of an incident and subsequent dispatch of resources including the process at the public safety answering center (PSAC). After an MCI, multiple calls to 9-1-1 may occur simultaneously.⁷ Similarly, information and notifications often occur from other first response agencies (eg, police, fire) via radio communication or computer messages. Ideally, there should be an organized process for filtering and managing this information. An agency must identify the process for escalation of EMS response and declaration of an MCI. Should this occur prior to event confirmation by on-scene resources? Can this be determined by the first-line call-taker or must the PSAC supervisory personnel be required to make the determination? It is easy to imagine the implications on a system if the determination of an MCI is delayed, thereby delaying a sufficient EMS response. Similarly, unnecessary overresponse can also have detrimental effects—when units are removed from 9-1-1 response duties, there are less resources to respond to non-MCI emergencies. Furthermore, these decisions must often be made rather quickly. Establishing clear guidelines for such situations is critical.

From a medical and EMS standpoint, the Emergency Medical Dispatch (EMD) will generally take responsibility for dispatching prehospital EMS resources to the scene of an event. Ongoing communication between EMD and the field responders should continue as the situation develops. Only with constant, effective communication can incident commanders and medical leadership make good operational and medical decisions.

ON-SCENE MANAGEMENT

In the initial stages of an MCI, chaos should be expected as an event unfolds. Chemical or radiologic threats, an active shooter, building collapse or secondary devices can complicate an effective response.^7–9

EMS agencies should have policies to establish a command structure immediately with the arrival of the first medical personnel that make clear considerations of scene safety. Depending on the nature of the event, key response components should be established including an incident command post, triage/treatment areas, a casualty collection point and staging areas for resources.

As the scale and scope of the event becomes clear, the onsite incident command should be established per local protocol. The incident commander (IC) is responsible for operational and tactical decisions on the ground, resource allocation, and overall scene management. The medical branch director must work with the IC to establish the most appropriate patient care for any given situation. In general, EMS, if not the lead agency, will, per protocol, designate an individual to act as a medical branch director (Box 75-1).

The essential role of the Medical Branch director in an MCI is to balance the triage, treatment, and transport of patients to minimize the morbidity and mortality of any given event. The medical branch director must direct available resources based on the resource availability of a region. Triage is discussed in depth in a separate chapter; however, it is worthwhile to mention that the scale of an event will skew the strategy (ie, if there is widespread facility or infrastructure destruction a greater proportion of care may occur in the prehospital setting).¹⁰ If the number of critical patients are greater than the number of transport resources or if there is widespread distribution, then the role of on-scene medical direction, treatment, and disposition becomes more important. On the other hand, if there are an adequate number of EMS resources, triage will be essential to quickly transport critical patients to definitive care.

ESTABLISHING COMMAND AND CONTROL

The EMS providers at a mass casualty event take on the primary role for patient care and transport. The plans must first identify the person who will be directing the EMS actions. In general, the first EMS providers on the scene assume the command role until higher level EMS providers or officers arrive and assume control. This may be counterintuitive to providers who want to rush to an individual patient’s rescue; however, first performing a rapid scene assessment and determination of need will better serve the MCI operation.

As higher level providers and leadership arrive to the scene, the command and control role typically transfers to those with higher authority. EMS providers are then assigned positions in the ICS format, which allows a clear line of reporting. There should be no confusion with regard to roles, responsibilities, and reporting.

TRIAGE, TREATMENT, CASUALTY COLLECTION, AND STAGING AREAS

The physical space where a mass casualty occurs will shape the operational context and thus the layout of how patients are cared for, where they are taken for safe immediate care and transport from the scene. Considerations should be made for CBRNE and provider safety (cold, warm, and hot zones) and issues related to ingress and egress of EMS vehicles.

Triage and Treatment Areas

Ideally, all mass casualty victims be transported from the scene immediately. However, in an MCI, usually, this is not possible. Therefore, it is necessary to 1) establish triage and treatment areas to separate critical from non-critical patients, perform life-saving treatments and develop a transport priority list; 2) Deploy treatment resources to dedicated areas, not an entire MCI scene and 3) Monitor multiple patients simultaneously.

Casualty Collection Point

The Casualty Collection point is a space designated by the medical branch director or IC to arrange for on-scene providers to meet transport resources.

Staging Area

The Staging Area is the site selected for resources to wait prior to arriving on the scene of an MCI. Selecting the staging area is key to ensuring that there is appropriate ingress and egress of emergency vehicles. Failure of appropriate staging or control of vehicles can contribute to delayed response and time to definitive care.¹⁰