key: cord-021701-yan5q2r7 authors: Woolard, Robert H. title: Emergency Department Design date: 2009-05-15 journal: Disaster Medicine DOI: 10.1016/b978-0-323-03253-7.50074-1 sha: doc_id: 21701 cord_uid: yan5q2r7 nan In the aftermath of recent terror events and subsequent disaster planning, hospital architects have begun to design EDs to better meet the needs anticipated from a terror attack. Some ED design lessons have been learned from terror events. From the Tokyo sarin gas event and other natural disasters, such as earthquakes, hospitals know they will need to plan for surge capacity. Methods of alerting ED staff early and protecting emergency care providers from contamination are needed, another lesson made clear by the Tokyo sarin gas event in which many emergency providers were contaminated. The New York City World Trade Center event illustrated the need to respond to a disaster scene and continue to treat a sustained increase in ED volume over prolonged periods. In New York, the clean-up phase after the event led to prolonged increased prehospital and ED volume. Most care was provided by emergency personnel working close to ground zero. From the anthrax mailings in the wake of the World Trade Center event, we can learn to anticipate the need for accurate public information. The ED remains the most available point of access to immediate healthcare in the United States. ED designers are now anticipating increased volumes of patients that might be generated by disaster or a terror event. Although a stressed public needs information and health screenings that perhaps can be met by providers outside the ED, the ED will be accessed for counseling and screening when other services are overwhelmed or delay to access is encountered. In past disasters, shelter needs were met outside the ED. However, needs for quarantine during bioterror events may create shelter needs in EDs. ED design and response capability after Sept. 11 has become a larger concern for public disaster planners, the federal government, and hospital architects. Two federally funded projects coordinated by emergency physicians, one at Washington Hospital Center (ER1) and another at Rhode Island Hospital (RIDI), have developed and released recommendations. ER1 suggests designs for a new ED that meets any and all anticipated needs of a disaster event. 3 RIDI has developed new disasterresponse paradigms, training scenarios, and response simulations that also can be used in ED design. 4 ED design would be tremendously enhanced if a prototype "disaster-ready" ED such as ER1 could be built. ED designers may not be able to create an "all-risks-ready"ED given financial constraints. However, incorporating disaster-ready suggestions when EDs are renovated or built new will improve our readiness and may be more financially feasible. New building materials, technologies, and concepts will continue to inform the effort to prepare EDs for terror attack. Urban ED trauma centers are attempting to develop capacity to serve as regional disaster resource centers and respond out to a terror event. These EDs are designed to incorporate larger waiting and entrance areas, adjacent units, or nearby parking spaces in their plans to ramp up treatment capacity. More decontamination and isolation capacity is being built to help control the spread of toxic or infectious agents. Information systems are being made available to provide real-time point-of-service information and any needed "just in time" training for potential terror threats. The technology needed to respond to a terrorist event, such as personal protective equipment (PPE), is becoming more widely available and is stored where easily available in EDs. Although mass decontamination can occur close to the disaster scene, EDs are gearing up to decontaminate, isolate, and treat individuals or groups contaminated with biologic or chemical materials. Four elements of ED design are being addressed to prepare EDs for terror events: scalability, security, information systems, and decontamination. EDs are generally designed with sufficient, but not excess, space. The number of treatment spaces needed in an ED is usually matched to the anticipated ED patient volume; roughly 1 treatment space per 1100 annual ED visits or 1 treatment space per 400 annual ED hospital admissions is recommended. 1 According to disaster planners, a major urban trauma center ED built for 50,000 to 100,000 visits per year should have surge capacity up to 100 patients per hour for 4 hours and 1000 patients per day for 4 days. One Sept. 11 challenge is to provide "surge capacity" to meet anticipated patient needs. Hospitals are woefully overcrowded, and EDs are routinely housing admitted patients. [5] [6] [7] EDs are now being designed to allow "growth" into adjacent space: a ground level or upper level, a garage, or a parking lot. Garage and parking lot space has been used in many disaster drills and mass exposures. Garages and parking lots are more purposely designed with separate access to streets, allowing separation of disaster traffic and routine ED traffic. Needed terror-response supplies (e.g., antidotes, respirators, personal protective gear) are being stored near or within the ED. The cost of ventilation, heat, air conditioning, communication, and security features often prohibits renovation of garages. More often, tents are erected over parking lots or loading areas. Modular "second EDs," tents or structures with collapsible walls (fold and stack), have been deployed by disaster responders. These can be used near the main ED, preserving the ED for critical cases. Some hospitals are considering beds in halls, patient rooms, and other spaces to increase their ability to generate surge capacity. Hallways can provide usable space if constructed wider and equipped with medical gases and adequate power and lighting. Often only minimal modifications are necessary to make existing halls and lobbies "dual-use" spaces. Some hospitals have increased space by installing retractable awnings on the exterior over ambulance bays or loading docks. Tents are often used outside EDs as decontamination and treatment areas in disaster drills. Tents with inflatable air walls have the added benefit of being insulated for all-weather use. In the military, the need to provide treatment in limited space has resulted in the practice of stacking patients vertically to save space and to reduce the distances that personnel walk. U.S. Air Force air evacuation flights have stacked critical patients three high. These bed units could be deployed for a mass event. Portable modular units are also available to help EDs address the space needs. Unfortunately, many EDs rely on other facilities in the regional system. In a terror event on a hospital campus, the ED function may need to be moved to a remote area within the hospital. Many disaster plans designate a preexisting structure on campus as the "backup" ED. The area is stockpiled with equipment, and plans for access and patient and staff movement are developed. Although the capacity to handle patient surges is being addressed regionally and nationally, large events with high critical care volumes may overtax the system of the trauma centers regionally. The National Medical Disaster System can be mobilized to move excess victims and establish field hospitals during events involving hundreds or thousands of victims. The ED plan to provide treatment during disaster must consider evacuation, since the event may produce an environmental hazard that contaminates the ED. Evacuation of ED patients has been addressed by ED designers. Some EDs have the capacity to more easily evacuate. In better planned EDs, stairwells have floor lights to assist in darkness. Stairways are sufficient in size to allow backboarded patients to be evacuated. The communication and tracking system includes sensors in corridors and stairways. Patient records are regularly backed up to portable disk and available for evacuation. Securing the function of an ED includes securing essential resources: water, gases, power, ventilation, communication, and information. ED security involves surveillance, control of access and egress, threat mitigation, and "lockdown" capacity. Surveillance exists in almost all EDs. Many ED parking and decontamination areas are monitored by cameras. The wireless tracking system can also be part of the surveillance system. A tracking system can create a virtual geospatial and temporal map of staff and patient movement. Tracking systems have been used in disaster drills to identify threat patterns. Most EDs have identification/access cards and readers. Chemical and biologic sensors for explosives, organic solvents, and biologic agents are becoming available. When selecting a sensor, designers consider sensitivity, selectivity, speed of response, and robustness. [8] [9] [10] [11] [12] Sensor technology is an area of active research that continues to yield new solutions that are being incorporated into EDs. In concept, all entrances could be designed to identify persons using scanning to detect unwanted chemicals,biologic agents,or explosives and to detain and decontaminate as needed. Most EDs have multiple entry portals for ingress of patients, visitors, staff, vendors, law enforcement personnel,and others. EDs are using screening and identification technologies at all entrances in combination with closed circuit video monitoring. Personnel must be dedicated for prompt response when needed. Automation of identification can efficiently allow safe flow of patients, staff, and supplies. Vehicle access has been managed by barcoding staff and visitor vehicles. At some road access points, automated scanners could monitor and control vehicle access. Modern EDs limit the number of entrances and channel pedestrian and vehicular traffic through identification control points. For the most part, points of entrance into the ED can be managed with locking doors, ID badge control points, and surveillance to allow desired access for staff and supplies. Thoughtful planning should facilitate rapid access between the functional areas such as the ED, operating rooms, and critical care units. Movement within and between buildings needs to be controlled and must allow a total lockdown when necessary. Direct threats to the ED include blasts and chemical, biologic, and environmental contamination. There are several strategies to mitigate blast. Twelve-inch-thick conventional concrete walls, using commercially available aggregates (147 lb per cubic foot) affords reasonable blast protection. 16, 17 On some campuses, the space between the ED and the entrance is designed largely to prevent direct attack. 18 However, atriums are terror targets. Although atriums are useful as overflow areas, their windows and glass create hazardous flying debris. Given the threat of blast attack, communication, gas, electric, water, and other critical services should be remote from vulnerable areas and shielded when they traverse roads and walkways. Protection against release of chemical and biologic agents inside or outside the ED requires a protective envelope, controlled air filtration in and out, an air distribution system providing clean pressurized air, a water purification system providing potable water, and a detection system. Better HVAC systems can pressurize the envelope and purge contaminated areas. Anticipated computing needs for ED operations during disaster events are immense. In most EDs, large amounts of complex and diverse information are routinely available electronically. Overflow patients in hallways and adjacent spaces can be managed with mobile computing, which is available in many EDs. Wireless handheld devices can facilitate preparation for disasters and allow immediate access to information by providers in hallways and decontamination spaces. Multiple desktop workstations are available throughout most EDs. During disaster, displays of information that will aid decisionmaking include bed status, the types of rooms available, the number of persons waiting, and ambulances coming in. Monitors now display patient vital signs, telemetry, and test results. Significant improvements in efficiency and decision-making can be achieved when more realtime information is available to decision-makers. Multiple computer screens enhance ED readiness. Clinical decision tools, such as UpToDate, 19 make information readily available to providers. These and other "just-in-time" resources will be needed when practitioners treat unusual or rare diseases not encountered in routine practice. The wide variety of potential disaster scenarios argues for the availability of just-in-time information. Information specific to a disaster event should be broadcast widely on multiple screens in many areas. Cellular links and wireless portable devices should also receive information. Access to information has been enhanced in most EDs through cell phone use, etc. This facilitates making information available to guide each staff member. Diagnostic decision support systems have been demonstrated to help practitioners recognize symptom complexes that are uncommon or unfamiliar. Information systems should be capable of communicating potential terror event information regularly. Many EDs have log-on systems that require staff to read new information. In a disaster-ready ED, a list of potential threats could be posted daily. However, the utility of computer references or on-call experts is limited by the practitioner's ability to recognize a situation that requires the resource. Computer-based patient-tracking systems are available for routinely tracking patients in most EDs. Some computer-based tracking systems have a disaster mode that quickly adapts to a large influx of patients allowing for collation of symptoms, laboratory values, and other pertinent syndromic data. In many regions, EDs serve as a terror surveillance network. Routine data obtained on entry are passively collected and transferred to a central point for analysis. In the event of a significant spike in targeted patient symptom complexes, these data can trigger an appropriate disaster response. The capacity for this entry point surveillance should be anticipated and built into any disaster-ready ED information system. [21] [22] [23] For example, data terminals allowing patient input data at registration similar to electronic ticketing at airports could passively provide information. This selfservice system could add to ED surge capacity. Similarly, real-time bed identification, availability, and reservation systems used to assist patient management in some EDs could aid ED function during disaster. Movement to an inpatient bed is a well-documented choke point recognized nationally during normal hospital operations and becomes an issue during disaster. Lobby screens can facilitate family access to information during a disaster, displaying information about the event and patient status. During disasters, family members can be given access to screens to query for missing persons. Computers with Internet access that could display event information are available in patient rooms in some EDs. During the anthrax mailings, public hysteria taxed the healthcare system. Posttraumatic stress, anxiety, and public concern over possible exposure to a biologic or chemical agent may generate a surge of minor patients at EDs. Within some EDs, lecture halls or media centers are available (generally used for teaching conferences) but could provide health information and media briefings during disaster. The media are an important source of public information and must be considered when planning disaster response. Information from a media center in the ED could be released to the Internet and closedcircuit screens. Accurate information can allay public concerns and direct the public to appropriate resources and access points. Many EDs have patient decontamination (DECON) areas. Adequate environmental protection for patients undergoing DECON is necessary and includes visual barriers from onlookers, segregation of the sexes, and attention to per-sonal belongings. 24, 25 In many EDs, DECON areas are being added to accommodate mass exposures. EDs have added or augmented DECON facilities. DECON areas should have a separate, self-contained drainage system, controlled water temperature, and shielding from environmental hazards. Exhaust fans are used to prevent the buildup of toxic fumes in these decontamination areas. For most EDs, mass DECON has been accomplished by using an uncovered parking lot and deploying heated and vented modular tent units. Uncovered parking areas adjacent and accessible to the ED have been enabled for disaster response. Other EDs use high-volume, lowpressured showers mounted on the side of a building. Serial showers allow multiple patients to enter at the same entrance and time. However, serial showers do not provide privacy, can be difficult for an ill patient to access, and can lead to recontaminated water runoff. Also, persons requiring more time may impede flow and reduce the number of patients decontaminated. Parallel showers built in advance or set up temporarily in tenting offer greater privacy but require wider space and depth. Combined serial and parallel design allows the advantages of each, separating ill patients and increasing the number of simultaneous decontaminations. 26 Often built into the ED is another DECON room for one or two patients with the following features: outside access; negative-pressure exhaust air exchange; water drainage; water recess; seamless floor; non-pervious, slipresistant, washable floor, walls, and ceiling; gas appliances; supplied air wall outlets for PPE use; high-input air; intercom; overhead paging; and an anteroom for DECON of isolated cases. PPE is recommended for use by military and fire departments during events involving hazardous materials. Hospitals use these devices and store a reasonable number of protective ensembles (i.e., gloves, suits, and respiratory equipment) usually near the ED DECON area. DECON areas are built with multiple supplied air outlets for PPE use to optimize safety and maximize work flexibility. A nearby changing area is available in some EDs. The changing area is laid out to optimize medical monitoring and to ease access to the DECON area. [27] [28] [29] [30] [31] Some capability to isolate and prevent propagation of a potential biologic agent has been designed into most EDs. Patients who present with undetermined respiratory illnesses are routinely sent to isolation. A direct entrance from the exterior to an isolation room is not usually available but has been a recent renovation in some EDs. Creation of isolation areas poses special design requirements for HVAC, cleaning, and security to ensure that infections and infected persons are contained. An isolation area should have compartmentalized air handling with high-efficiency filters providing clean air. [32] [33] [34] [35] Biohazard contamination is particularly difficult to mitigate. Keeping the facility "clean"and safe for other patients is an extreme challenge. Biologic agents of terrorism may resist decontamination attempts. Infected patients present a risk to staff. Few triage areas and ED rooms have been designed for decontamination. Surfaces must be able to withstand repeated decontamination. Sealed inlets for gases and plumbing have also been considered. [36] [37] [38] Patients who are isolated can be observed with monitoring cameras. Some isolation areas include a restroom within their space, which helps restrict patient egress. General ED areas could have DECON capabilities built in. Floor drains have been included in some ED rooms for easier decontamination. Infection control is improved using polymer surface coatings that are smooth, nonporous, and tolerant to repeated cleaning, creating a virtually seamless surface that is easy to clean. These coatings can be impregnated with antimicrobial properties enhancing their biosafe capability. Silverimpregnated metal surfaces in sinks, drains, door handles, and other locations can reduce high bacterial content. Silver-impregnated metal has demonstrated antimicrobial effects. 39 Conventional ventilation systems use 15% to 25% outside air during normal operation, thus purging indoor contaminants. Air cleaning depends on filtration, ultraviolet irradiation, and purging. HVAC design should model demand for adequately clean air and also for isolation of potential contaminants. 40 The disaster-ready ED requires protection from external contaminations as well as contagious patients. A compartmentalized central venting system without recirculation has the ability to remove or contain toxic agents in and around the ED. Compartmentalized HVAC systems allow for the "sealing" of zones from each other. More desirable HVAC systems electronically shut down sections, use effective filtration, and can "clean" contaminated air. A compartmentalized system can fail, but it only fails in the zone it is servicing; smaller zones mean smaller areas lost to contamination. These systems are less vulnerable to global failure or spread of contamination. Modular HVAC units developed for field military applications have been added to existing ED isolation areas for use when needed to create safe air compartments. Cost may prohibit addressing issues like building more space or better ventilation, decontamination, and isolation facilities. If added space and facilities are not made more available, many lives may be lost during a disaster event. When monies are spent for terror readiness, EDs must continue to function day to day. EDs will be challenged to provide efficient routine care and also handle the consequences of a terror event or natural disaster. These competing functions could result in EDs that cannot handle routine care. These design efforts could also lead to unnecessary increases in expenditures in anticipation of terror events that never materialize. To the extent that efforts to provide disaster care can be translated into solutions that address other more immediate hospital and ED problems, they will gain support. More access to information systems providing just-in-time training could inform staff not only of terror events but of mundane policy changes and unique patient needs such as bloodless therapy for Jehovah's witnesses, etc. Better information access could also improve routine ED efficiency and communication with patients and families. However, these rationales may not prevail to fund disaster readiness. Decontamination equipment and areas may be used for commercial hazardous materials spills. Isolation areas could be more routinely used in an effort to contain suspected contagions, such as severe acute respiratory syndrome (SARS). Lack of bed capacity in hospitals leads to ED overcrowding. Scalable EDs may offer temporary solutions in times of over-burdened hospital inpatient services. However, once reserve spaces are used to solve other over-capacity problems, those spaces may no longer be available for disaster operations. Thus, a new facility could "build" the capability of handling large surges of patients into adjacent spaces, only to lose it by filling these spaces with excess patients whenever the hospital is over census. Finally, a terror event may be different from those for which we prepare. The rarity of terror events creates a need for us to test our disaster plans, skills, and capacities in drills. Drills may uncover design problems that can then be addressed but may only prepare us for anticipated threats. Why pour such resources into building capacity that we hope never to use? Among the lessons learned from past disaster events is the need to develop disaster skills and build a disaster-response system from components that are in daily use. Systems that are used routinely are more familiar and more likely to be used successfully during terror events. Certainly the surge capacity of a "terror-ready" ED would be used for natural disaster response and in disaster drills. The surge space could also be used for over-census times, public health events, immunizations, and health screenings. A modern ED should serve as a community resource, deploy and test capacities regularly in disaster drills, and maintain "readiness" in a post-Sept. 11 world. Australian College for Emergency Medicine Functional and Space Programming. Dallas, Tex: American College of Emergency Physicians Rhode Island Disaster Initiative. 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