FIGURE 156.1 Hospital incident management team. (Adapted from Hospital Incident Command System Guidebook. 5th ed. California Emergency Medical Services Authority website. Available at: http://www.emsa.ca.gov/media/default/HICS/HICS_Guidebook_2014_11.pdf. Published May 2014; Accessed January 14, 2016. Copyright © 2014 by California Emergency Medical Services Authority [EMSA].)
Other recent terrorist activities include biochemical attacks, such as the tainting of salad bars at The Dalles, Oregon, in 1984 with Salmonella typhimurium by the Rajneeshee cult (16); the release of anthrax in Tokyo in 1993 by the Aum Shinrikyo; and the distribution of anthrax in the US mail in 2001, which affected postal workers, the news media, and politicians and their staff. Aum Shinrikyo also claimed responsibility for the release of sarin gas in the subway system in Tokyo in 1995 (17).
There are significant concerns that bombing activities may evolve into improvised radiologic dispersal devices (RDDs)—a conventional bomb contaminated with radioactive waste material, also known as a “dirty bomb” (18)—as well as the release of biologic or chemical agents.
Accidental releases of chemical agents have been an unfortunate result of industrialization and are ever-present threats of which governments and the population at large must be aware. One of the most devastating events of this nature was the accidental release of methylisocyanate gas in Bhopal, India, in 1984 (19), resulting in the deaths of more than 3,000 people with over 500,000 injured. Similarly, the quest for energy through nuclear reactors resulted in the radiologic accidents of Chernobyl in the Ukraine in 1986, and Three Mile Island, Pennsylvania, in 1979. Although these events occurred in stationary structures and threatened surrounding communities, one must keep in mind that this type of risk may be transported over the railway or highway systems through any area in the form of hazardous chemicals, waste materials, and munitions, or due to lack of proper disposal, as in the case of Goiania, Brazil, in 1987, in which 93 g of caesium-137 was stolen from an abandoned radiotherapy device and manipulated in scrapyards, resulting in several fatal and severe exposures (20).
FIGURE 156.2 Diagram of responsibility for incident command showing interaction of the HICS with other agencies and the public. CEO, chief executive officer; EOC, emergency operations center; ESF, emergency support function; JIC, joint information center; MACS, multiagency coordination system; MMRS, metropolitan medical response system. Solid lines show fundamental relationships; dashed lines show potential relationships. (Adapted from Hospital Incident Command System Guidebook. 5th ed. California Emergency Medical Services Authority website. Available at: http://www.emsa.ca.gov/media/default/HICS/HICS_Guidebook_2014_11.pdf. Published May 2014; Accessed January 14, 2016. Copyright © 2014 by California Emergency Medical Services Authority [EMSA].)
Nature itself has caused a fair share of mass casualty incidents. Geotectonic events have demonstrated the potential for chaos and destruction as the result of earthquakes, tsunamis, volcanoes, landslides, and avalanches, to name but a few of the hazards nature can unleash upon us. Atmospheric phenomena have impacted vast populations in a repetitive fashion, most recently major catastrophes such as tropical storm Allison in 2002, and hurricanes Katrina and Rita in 2005. More recently, in 2011, we witnessed how a magnitude 9 earthquake in northeastern Japan generated a tsunami that resulted in great loss of life and the meltdown of three reactor cores of the Fukushima nuclear complex, causing a significant amount of radioactive material leak into the bed of the Pacific Ocean and contaminating the food supply of the population (21).
Taking into consideration historical aspects, scientific forecasting, and the possibility of terrorist targeting, all communities, whether large or small, should complete a “hazard vulnerability analysis” (HVA) that can assist in the planning and identification of resources aimed at the mitigation of the event’s impact (22).
INITIATIVES IN THE UNITED STATES
The transformation of the “ambulance” system into an emergency medical system (EMS) in the United States in the late 1970s brought about the development of an infrastructure that served as the backbone to respond to mass casualty incidents. The early focus on the prehospital setting has helped in the development of the Incident Command System (ICS) and the National Incident Management System (NIMS) (23) as a way to organize a single or multi-institutional response. These efforts have been paired with the development of the National Disaster Life Support (NDLS) (24) program, which has a variety of courses targeted to field providers and hospital personnel. The details of these programs require theoretical and practical training, but are, unfortunately, beyond the scope of this chapter.
An adaptation of the ICS evolved into the Hospital Emergency Incident Command System (HEICS), more recently renamed and organized as the HICS (5) as a means to assist hospitals in improving their emergency management planning, response, and recovery capabilities for unplanned and planned events. The required surge capacity response of the ICU has been a priority concern at the Society of Critical Care Medicine (SCCM), and has led to the development of the Fundamentals of Disaster Management (FDM) course (25,26). This course includes didactic and hands-on development of skills to utilize equipment provided by the Strategic National Stockpile (SNS), and targets intensivists and hospital staff.
Decontamination and First Receivers
Education of proper decontamination techniques for various agents must be included in any plan for a hospital to respond to a multiple casualty incident (MCI). Improper technique, or lack of deployment, may lead to exposure of the ED personnel and the facility in general, as was experienced in 1995 in Tokyo with the release of sarin in the subway system (17,27). Thus, it is imperative to ensure that correct decontamination procedures are completed prior to allowing ED personnel access to exposed persons. Any suspicion or doubt regarding this aspect of care should result in repeating the decontamination process prior to entering the facility.
The decontamination process begins with the designation and enforcement of perimeters around the hospital to ensure that patients flow through predetermined corridors. Some patients may arrive at hospital by their own means, without any in situ decontamination performed by first responders, and others may arrive with incomplete decontamination. In most instances, any patient should go through a thorough, supervised, and complete decontamination prior to accessing the inside of the facility.
Hospital Perimeters
Traditionally a hospital perimeter is divided into three areas, or zones.
Hot zone: This zone represents everything outside the facility’s perimeter. The hot zone is where patients have not been through decontamination or triage, and where credentials for access have not been verified by security or screening personnel.
Warm zone: This is the transition zone, where decontamination and triage happens. This is also where security personnel verify credentials and health screening clearance for access, depending on the nature of the event.
Cold zone: This is the “inside” of the hospital. Patients will access this zone only after decontamination is completed and verified. Health care providers are granted access after credentials and health status are corroborated.
TYPES OF DECONTAMINATION
Primary Decontamination
This occurs when the individual’s clothes are removed, in conjunction with showers with a low-pressure, large-volume water delivery system, such as the Trident (28) (Fig. 156.3). In colder climates, it is important to ensure warm water delivery systems, as well as consideration of indoor or pool decontamination techniques (29) (Fig. 156.4), in order to minimize exposure and improve compliance. Privacy is another major consideration that will help improve compliance by the establishment of corridors and barriers installed to protect patients’ dignity after clothing has been removed for decontamination.
Secondary Decontamination
This is performed by either health care workers following specific guidelines for nonambulatory patients or by the ambulatory patients themselves following clearly written and pictorially explicit instructions made available in the most common regional languages to accomplish self-decontamination. This latter group would then only require minor supervision from health care workers to ensure proper compliance.
Although many solutions have been proposed for use during this stage of decontamination, it is now recommended that plain water, in conjunction with scrubbing, be used. This can usually be implemented very quickly in order to expedite the removal of the agent and decrease any possible absorption. In some instances, the application of mild soapy solutions can be used for oily residues; however, the decontamination process should not be delayed to add soap (30).
Some hospitals have incorporated permanent decontamination areas, such as showers and rooms, within their architectural façade design at the ED entry; others rely on the quick deployment of tents (Fig. 156.5) or temporary decontamination corridors with low-pressure, high-volume expanded shower triple system (see Fig. 156.3), or via water hoses from fire engines (Fig. 156.6).
FIGURE 156.3 Low-pressure high-volume expanded triple system deployed with fire hydrant connection. (Courtesy of Orlando Regional Medical Center.)
FIGURE 156.4 Decontamination (Decon) methods based on ambient temperatures. (Adapted from U.S. Army Soldier and Biological Chemical Command (SBCCOM). Guidelines for cold weather mass decontamination during a terrorist chemical incident. Edgewood Chemical Biological Center website. Available at: http://www.ecbc.army.mil/downloads/cwirp/ECBC_cwirp_cold_weather_mass_decon.pdf. Published January 2002; Accessed October 27, 2008.)
The contaminated water is ideally pumped from the containment pools to bladders and cisterns that will require special disposal. The Environmental Protection Agency and the Occupational Safety and Health Administration (OSHA) have recommendations for managing these waste materials (31). However, even though all efforts should be made to protect the environment from potential long-term contamination, patient assessment and management should proceed without delay.
FIGURE 156.5 Inflatable decontamination tent. (Courtesy of Orlando Regional Medical Center.)
Chemical Decontamination
Proper chemical decontamination begins with the identification of the potential agent. This can be accomplished by evaluation of the clinical presentation, or by using definitive colorimetric chemical identification kits similar to the military-type M-8/M-9 paper, or through electrochemical sensors, radiologic detectors, surface acoustic wave technology, infrared mass spectroscopy, and/or ion mobility spectroscopy units.
FIGURE 156.6 Emergency decontamination corridor system with fire engines and ladders. (From U.S. Army Soldier and Biological Chemical Command (SBCCOM). Guidelines for mass casualty decontamination during a terrorist chemical agent incident. Intelcenter website. Available at: http://www.chem-bio.com/resource/2000/cwirp_guidelines_mass.pdf. Published January 2000; Accessed October 27, 2008.)
Radiologic Decontamination
The presence of radioactive material requires very specific equipment to ensure proper decontamination. Multiparticulate detectors (e.g., the Geiger–Muller counter) can be used for initial detection, as well as to ensure adequate decontamination. Extreme care should be used to prevent contamination of these devices. The scanning should be performed closely but without any skin contact, with a plastic disposable cover. Other devices are limited and can detect only a limited number of particle types. Except for cases of internal or absorbed radioactive contaminants, external decontamination is carried out with plain water and scrubbing, and should be repeated until the skin shows no evidence of emissions.
Protective Equipment for Decontamination
First receivers include hospital employees working at a site remote from where the “release” occurred. They should use the appropriate PPE based upon the stage of the decontamination process on which they are working. The primary first receivers have the highest risk and, thus, require a higher level of protection. The delineation of their training and level of protection is beyond the scope of this chapter, but is described in detail in the OSHA publication Best Practices for Hospital-Based First Receivers (32).
Classes of PPE include Level A, B, and C ensembles.
Level A ensembles include the highest level of respiratory protection—a self-contained breathing apparatus that is worn inside vapor-protective chemical clothing.
Level B ensembles involve heavy-splash chemical protective clothing with the use of self-contained breathing apparatus (some PPE in this level may be encapsulated but should not be confused with the garment rating of vapor protective).
Level C ensembles involve light-splash chemical clothing in conjunction with either a filter cartridge face mask or powered air-purifying respirator (PAPR) in which the appropriate filter that provides respiratory protection must be used for the specific product involved within a qualified atmosphere containing an appropriate level of oxygen.
Because of the dynamics involved, level C ensembles are usually suitable for hospital first receivers (based upon the specifics of the substances involved), and consist of a chemical-resistant suit, two layers of gloves, chemical-resistant boots, and a breathing device.
In most cases, more complex systems requiring compressed air are not warranted at the hospital, and are usually reserved for first responders at the area of the primary event. Efforts toward establishing a relationship with the local hazardous materials team will provide the following benefits: recognition of jurisdictional capabilities, improved communication between on-scene first responders and the ED first receivers, and established trust for accuracy of relayed chemical hazard information and/or personnel protective equipment selection criteria.
The donning of this equipment represents a significant added physical and emotional stressor for first receivers. In order to minimize potential complications, a set of minimal physical conditions are required prior to its utilization; periodic checks and a “buddy system” are recommended (32). First receivers should have scheduled training sessions in order to don and doff their gear properly. They should also follow clear guidelines for adequate rotations, rehydration, and monitoring. First receivers have an average effective time of about 20 minutes, which can be significantly shortened due to weather conditions. Cooling vests with packaged dry ice or water-recirculation suits have been used in warm climates and may triple the effective time, but close monitoring is still required.
Once decontaminated, the patient may require placement in isolation areas with or without negative environmental pressure. All personnel in the cold zone that come in contact with patients exposed to a potential biologic agent should wear, at minimum, gear consisting of a liquid-proof disposable gown (Tyvek or similar material), gloves, goggles, and surgical mask. Depending on the agent, higher levels of respiratory protection may be required.
ROLE AND EXPECTATIONS OF THE INTENSIVIST
Hospitals and local and regional disaster committees should include a critical care expert to optimize critical care surge capacity planning for “conventional,” “contingency,” and “crisis” levels; estimating surges of 20%, 100%, and 200%, respectively (3). The interaction should include ED staff, administrators, pharmacists, and engineers, as well as local first responders, area hazardous materials teams, and community services leaders in order to develop a plan that includes triggers, communications, personnel distribution, equipment and medication stocks, surge areas and facilities, and ongoing education and drills.
PLANNING AND AUGMENTING RESPONSES
In the United States, most medical facilities are functioning at full or near-full capacity during routine operations (6). This is further complicated by ongoing health care worker staff deficits; therefore, staffing and personnel should be a major focus in the planning of a “surge” response during an MCI. Basic surge considerations have been enumerated by Rubinson et al. (6) and are summarized in Table 156.1. The American College of Chest Physicians and the European Society of Intensive Care Medicine have published comprehensive recommendations of their task forces that go beyond the scope of this chapter (3,4).
CLASSIFICATION AND INITIAL TREATMENT
Biologic Threats
The biologic threats are classified as category A, B, or C based on their availability, potential for dissemination and infectivity, and their ability to cause events of large magnitude; category A agents are the most severe. Table 156.2 summarizes early warnings of a biologic threat event, signs and symptoms of syndromes caused by biologic agents, and initial steps to take if an illness is suspected to be related to a bioterrorism activity or spread of a highly contagious biologic agent. Tables 156.3 and 156.4 enumerate the clinical presentations, diagnostic tests, and available treatments for category A and categories B and C, respectively; Table 156.5 details dosing of drugs for adult treatment of potential bioterrorism agents.
Chemical Threats
The chemical agents are divided in five different groups.
- Nerve agents: Anticholinesterase activity
- Asphyxiants or blood agents: Cyanide based
- Choking or pulmonary-damaging agents: Direct airway cytotoxicity
- Blistering or vesicant agents: Direct skin cytotoxicity; may also affect airway
- Incapacitating agents: For riot control
The details on agents, symptoms, detection, and basic treatment are listed in Table 156.6.
PERSONAL PROTECTIVE EQUIPMENT IN THE ICU
As evidenced during the SARS and EVD epidemics, following the recommendations for donning and doffing personal protective equipment in the ICU, resulted in health care workers contracting the illnesses when they were taking care of affected patients. Based on the experience from Toronto, Canada, and the work of Zamora et al. (33), the CDC modified their recommendations for PPE when high risk for aerosolization exists (26); similar recommendations from the FDM course (25) are summarized in the following paragraphs.
If possible, a designated area in the ICU should be turned into a negative pressure environment; patient rooms should function as negative pressure areas as well, either by design or by installing portable negative pressure units. The ICU ideally should have areas dedicated to donning and doffing. If due to the physical distribution of rooms or in massive events, when this is not possible, the entire ICU should be considered a “warm” zone, where all staff—including medical, nursing, respiratory therapy, secretarial, and housekeeping—wear a basic layer of PPE that includes the following.
- Scrubs
- Gown
- Gloves, with longitudinal taping
- N-95–type mask
- Nonabsorbent-material shoes
The donning and doffing of PPE should follow a detailed checklist incorporating a trained observer, the “buddy” system, to ensure that the steps are followed in the recommended sequence, and none is skipped or missed. During the Ebola epidemic, the CDC reviewed their guidelines that are very similar to the recommendations of the Canadian authorities during the SARS epidemic. These increase the respiratory protection to that of airborne level, in view of the risk of aerosolization created in the ICU and other acute care facilities during the provision of treatment and procedures. It is recommended to follow them in their sequential detail for donning and doffing to decrease the potential exposure of health care personnel. These are kept and updated at the CDC website.
If a patient’s room needs to be accessed for routine care (e.g., monitoring, titration of IV treatments, positional changes, adjustment of ventilator settings, or blood sampling) that would not result in the generation and dispersion of aerosols, a second layer of PPE is recommended that includes the following.
- Eye protection (goggles)
- Hair-covering device (hair net or hat)
- A second gown
- A second layer of gloves, with longitudinal taping (Fig. 156.7)
If the patient’s room needs be accessed for airway manipulation, where there is a high risk for aerosolization of secretions (e.g., the use of bag valve mask, endotracheal intubation, open circuit suctioning, bronchoscopy, or disconnection from ventilator), the highest level of PPE should be used, including a PAPR, as well as the second layer noted above (Fig. 156.8). The PAPR used indoors in the ED or ICU should be of a light material, and should not be confused with the PAPR used in decontamination lines at the entrance of the hospital. This “indoor” PAPR offers high-level protection for biologic agents only, and is available as a face shield (higher chance of neck contamination with aerosols) or as a full hood, the preferable type, as it covers well the skin of the neck area (Fig. 156.9).
| TABLE 156.1 Planning Assumptions and Recommendations for Mass Critical Care |
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