Emergency preparedness encompasses the planning and response to disasters. A disaster is defined by the World Health Organization (WHO) as a sudden phenomenon of sufficient magnitude to overwhelm the resources of a hospital, region, or location requiring external support. Based on this definition, a disaster could be as large as the terrorist attacks of September 11, 2001, or as small as a single patient with an infectious disease. Defining a disaster ultimately depends on the type of event, timing, the severity of illness or injuries, local preparedness, and resources available. Disasters are described as either internal or external disasters. Internal disasters are events that occur within the walls of the hospital itself such as an active shooter, power outage or radiation exposure.
External disasters occur at locations separate from the hospital such as transportation incidents or industrial accidents. Disasters can be both internal and external disasters concomitantly, such as natural disasters that cause mass casualties as well as damage hospital structure. Disasters can be acute or ongoing. Acute disasters have a general time of onset of the time of an event occurring. Acute disasters have a typical patient flow which produces numerous low acuity patients presenting to the hospital which overwhelms the surge capacity, or the number of patients the facility can care for presenting at a single time. This surge event is followed by the majority of patients presenting by personal transport and later EMS or prehospital transport of the critically ill. Peak volumes in acute disasters are expected at two to three hours post event. Evolving disasters such as infectious pandemics have a gradual progression to critical populations, but volumes and resource strain remain for extended periods of time. Disaster types can further subdivide into categories such as natural disasters, chemical disasters, and bioterrorism; each subdivision produces a specific injury or exposure profile and individual strain on resources which can guide emergency preparedness planning and response.
Emergency preparedness encompasses diverse fields within the hospital and regional setting. Planning membership groups should address key aspects across these fields including but not limited to: public safety, facilities, logistics, pharmacy, transportation, clinical patient care, non-clinical patient care, media/public relations, communications, radiation, infection control, and administration. These key members must develop specific plans to address the facility or region they serve to prioritize resources to address the most severe disasters they may face in an ongoing or continual process of evaluation and training.
Emergency preparedness follows three main stages:
In the United States, the Federal Emergency Management Agency (FEMA) which operates as part of the Department of Homeland Security (DHS) controls emergency management. Initially, management of all disasters is at the local level via facility groups, police, fire, and EMS. Once local authorities become overwhelmed, the disaster management transitions to the state level, with FEMA acting as an assisting agency rather than an authoritative leader. FEMA organizes the nation and its territories into 10 regions. The Citizen Corps is a volunteer organization that works to educate and train the public for emergency response. These services are performed locally and organized through DHS.
In the event of a terror-related disaster, the Secretary of Homeland Security starts the National Response Framework (NRF) which integrates federal resources with state and local resources for management of resources at the lowest possible level.
The Centers for Disease Control and Prevention (CDC) provides education and information regarding specific disaster types including infectious diseases, chemical and radiation exposure, and natural disaster or weather-related incidents.