Emergency Care Textbook Professional Responders-part-21.pdf

21 Multiple-Casualty Incidents Key Content Organizing Resources............. Caring for the Ill or Injured.... Triage.................................... CBRNE Emergencies................ Types of Agents.................... Methods of Dissemination................... Scene Assessment...................

21 Multiple-Casualty Incidents Key Content Organizing Resources............. Caring for the Ill or Injured.... Triage.................................... CBRNE Emergencies................ Types of Agents.................... Methods of Dissemination................... Scene Assessment................. Establishing Perimeters....... Triage in a CBRNE Incident............................. Control of Contaminated Casualties.......................... Transporting CBRNE Patients.............................. Psychological Impact of CBRNE Events.................... 358 359 359 361 362 363 364 364 364 364 365 365 As the term implies, a multiple-casualty incident (MCI) refers to a situation involving two or more patients. You are most likely to encounter MCIs involving only a few patients, such as a motor vehicle crash involving a driver and a passenger. MCIs can also be large-scale events, involving dozens or even hundreds of patients. Examples of MCIs include: Floods Fires Earthquakes Tornadoes Hurricanes Explosions Structural collapses Train derailments Airline crashes Hazardous material incidents MULTIPLE-CASUALTY INCIDENTS Introduction 357 Incidents of this magnitude can strain the emergency response resources of local communities. Coping effectively with an MCI requires a plan that enables you to acquire and manage the necessary personnel, equipment, and supplies. Organizing Resources INCIDENT COMMAND SYSTEM (ICS) Because incidents vary in complexity, providing appropriate assistance to multiple patients in an emergency involves organization. MCIs can strain the resources of the responding personnel and require additional resources. The incident command system (ICS) was developed to ensure that the various resources operate in an orderly, cohesive fashion. ICS is a component of the Incident Management System (IMS). MULTIPLE-CASUALTY INCIDENTS The key components of an ICS are: 1. Incident Command. 2. Operations. 3. Planning. 4. Logistics. 5. Finance/Administration. 358 There are a number of sectors within the ICS, each with individual areas and responsibilities. Each sector has a supervising officer. As designated by command, the officers may include the following (Figure 21–1): Triage officer: Supervises assessment, tagging, and transportation of patients to designated treatment areas. Treatment officer: Sets up a treatment area and supervises treatment, making sure the most seriously injured are treated and/or transported first. Transportation officer: Arranges for patient transport while also tracking the priority, identity, and destination of all patients leaving the scene. Staging officer: Releases and distributes resources as needed and ensures that there is no transportation gridlock. Safety officer: Maintains scene safety by identifying potential hazards and taking actions to prevent them from causing injury. This officer has the authority to suspend, alter, or terminate any actions that are deemed unsafe. The ICS is designed to apply in a wide variety of emergencies. It is a common system that can be easily understood by different agencies working together at the scene of an emergency. Originally developed in California to manage the large numbers of firefighters necessary for major brush and forest fires, the ICS has subsequently been modified for use in a variety of MCIs. An ICS is similar to an organization: a group of people working together to achieve a common goal. The organization must clearly define who is in charge, the scope of authority and responsibility, the goal, and the objectives to accomplish the goal. The advantages of using the ICS include: Establishing a common vocabulary for all parties involved. Creating an integrated communications system. Establishing one commander who can make rapid, informed decisions. Creating a unified command structure with well-established divisions. Creating easily managed units, normally consisting of no more than four people. Using the Incident Command System A police officer is dispatched to a single motor vehicle collision. Since she is the first responder to arrive at the scene, she assumes the role of incident commander. She assesses the scene to determine the magnitude of the incident. She makes the scene safe for herself, bystanders, and any patients. Once the scene is safe, she approaches the vehicle. The driver has already left the vehicle and is seated on the curb next to the vehicle. The officer determines that the driver is the only injured person and approximates the type of injuries. She then notifies the dispatcher of the situation, requesting only one ambulance as an additional resource. She gathers information from the patient while providing care until more advanced medical personnel arrive. Once the patient is turned over to the arriving paramedics, the officer reassesses scene safety, checks to make sure nothing else is needed, finishes gathering information, and completes any paperwork. In this situation, the required resources were minimal. But what if the car had struck a utility TRANSPORTATION TRIAGE STAGING TREATMENT SAFETY INCIDENT COMMAND Figure 21–1: Basic structure of an incident command system. pole and knocked down an electrical wire, the injured person had been trapped in a crushed vehicle, or multiple people had been injured? As the incident commander, the police officer would have notified the dispatcher of the situation and requested additional resources. She would have summoned the power company for the downed wire. If a person was trapped in the vehicle, resources such as the fire department or specialized rescue squad personnel would have been sent to the scene. services are used will be based on your expertise and the needs at the time. Your role could include assisting medical personnel, aiding in crowd or traffic control, helping to maintain scene security, or helping to establish temporary shelter. By using the ICS in numerous emergencies, the tasks of reaching, caring for, and transporting patients are performed more effectively, thereby saving more lives. Since there are variations in the ICS throughout the country, you should become familiar with the ICS for your local community. As these personnel arrive, the police officer could continue to act as the incident commander, or command could be turned over to other, more experienced personnel. These decisions are often based on the type of emergency and on local protocols. If the incident is beyond your scope of practice, you should act as incident commander only until more experienced personnel arrive. At this point, command will usually be transferred to the most experienced officer. Caring for the Ill or Injured In previous chapters, you learned how to conduct a systematic assessment of a patient. This enabled you to identify and care for life-threatening emergencies before minor injuries. Although this approach is appropriate for one patient, it is not effective when there are fewer responders than there are patients. If you took the time to conduct a full primary and secondary assessment, providing care for all problems that you found, your entire time could be spent with MULTIPLE-CASUALTY INCIDENTS At other times, you may be responding to a large-scale MCI because it requires additional personnel. Where you are placed and how your TRIAGE 359 just one patient. A patient who is unresponsive and not breathing because the tongue is blocking the airway could be overlooked and die while your attention is given to someone with a minor injury. Pediatric triage may differ in some jurisdictions according to local protocol. In an MCI, you must modify your patient assessment model. This requires you to understand your priorities. It also requires you to accept death and dying: Some patients, such as those who would normally receive CPR and be high priority, may be beyond your ability to help in an MCI. To identify which patients require urgent care in an MCI, you use a process known as triage. Triage is a French term that was first used to refer to the sorting and treatment of those injured in battle. Today, the triage process is used any time there are more patients than responders. It is a system for sorting patients into categories according to the severity of their injuries or illnesses. There are many different triage models in existence. Make sure you are familiar with the system used within your local jurisdiction. MULTIPLE-CASUALTY INCIDENTS The START System 360 Over the years, a number of systems have been used to triage patients. Most, however, required you to diagnose the exact extent of the injury or illness. This was often time-consuming and resulted in delays in assessment and care for people in MCIs. As a result, the START system was created. START stands for Simple Triage And Rapid Treatment. It is a simple system used to quickly assess and prioritize patients. The START system requires you to assess only three factors: respiration, circulation, and level of responsiveness. Based on this assessment, you will classify patients into one of four levels that reflect the severity of injury or illness and need for care. These levels are minor, immediate, delayed, and dead/non-salvageable. Using the START system requires the first responders on the scene to clear the area of all those patients in the minor category, which consists of patients with only minor illnesses or injuries. These patients are sometimes referred to as walking wounded. If a patient is able to walk from the site of the incident without assistance, allow him or her to do so. Have these patients walk to a designated area for evaluation by arriving medical personnel. Next, quickly assess the remaining patients. As you do so, you are attempting to classify each patient into one of the three remaining categories. The second category is delayed care. Patients assigned to this category have respiration, circulation, and a level of responsiveness within normal limits (and so do not require immediate interventions), but are not able to move (e.g., because of a broken leg) The third category is immediate care, meaning that the patient needs to be immediately transported to a medical facility. An example of an immediate patient is one who requires emergency surgery for internal hemorrhaging. The final category is dead/non-salvageable. This category is assigned to those individuals who are obviously deceased. Patients who are initially found not breathing and who fail to breathe after attempts are made to open and clear the airway are classified as dead/non-salvageable. This is also true for obvious mortal injury, such as decapitation. As you classify each patient into one of these four categories, you need to mark the patient in some distinguishing manner so that other responders will be able to easily identify the most critical patients first. This process of labeling patients is easily done with commercial triage markers or multi-coloured tape, which should be fastened to the patient in an easily noticeable area, such as around the wrist (Figure 21–2). Colour codes are as follows: Minor = green Delayed = yellow Immediate = red Dead/non-salvageable = black or grey Check Respiration When you locate a patient, begin by assessing his or her respiration. If the patient is not breathing, clear the mouth of any foreign objects and make sure the airway is open. If respiration is still not present, the patient is classified as dead/nonsalvageable. There is no need to check the pulse. Place a black or grey marker on the patient and move on. If the patient’s respiration is present, you must check the rate. A patient with a respiration rate of more than 30 breaths per minute should be classified as immediate. A patient with a rate of less than 30 breaths per minute should be further evaluated. This requires you to move to the next check—circulation. Check Circulation The next step is to evaluate the circulation. You do this by checking the radial pulse. You are only assessing the presence or absence of the radial pulse, not its quality. If you cannot find the radial pulse in either arm, then the patient’s blood pressure is very low. Control any external hemorrhaging by using direct pressure and applying a pressure bandage. Place the patient in the immediate category and move on to the next patient. If the pulse is present and no hemorrhaging is evident, conduct the final check— level of responsiveness. Figure 21–2: Example of a multiple-casualty incident tag. This final check will serve to classify this patient. You determine the patient’s level of responsiveness by using the AVPU scale (see page 83). A patient who is alert and responds appropriately to verbal stimuli should be put into the delayed category. Someone who remains unresponsive, responds only to painful stimuli, or responds inappropriately to verbal stimuli is classified as immediate. By using the START system, you will be able to move quickly among patients, assessing and classifying them. Remember, your role is not to provide extensive care for the patient. Instead, you are expected to assess as many patients as possible. You should not pause the triage process to perform CPR: A patient in cardiac arrest is in the dead/non-salvageable category. Table 21–1 provides a simple overview of the START classification system. Check Level of Responsiveness CBRNE EMERGENCIES At this point, you have determined the following about the patient: Respiration is normal (fewer than 30 breaths per minute). Radial pulse is present. (A hemorrhage may or may not be present.) CBRNE stands for Chemical, Biological, Radiological, Nuclear, Explosive. It is the general term used in Canada to refer to weapons of mass destruction (WMDs). CBRNE events involve the intentional use of chemical, biological, MULTIPLE-CASUALTY INCIDENTS If the patient does begin to breathe on his or her own when you open the airway, this patient should be classified as needing immediate care. Any individual who needs help maintaining an open airway is a high priority. Position the patient in a way that will maintain an open airway, place a red tag on the patient, and move on to the next patient. Once triage of all patients is complete, you may be able to come back and assist with care for patients in the immediate category. 361 TABLE 21–1: START CLASSIFICATION SYSTEM MINOR (GREEN) DELAYED (YELLOW) IMMEDIATE (RED) Walking without assistance Respiration normal, radial pulse present, and level of responsiveness normal radiological, nuclear, or explosive materials to cause harm. These are criminal acts and, depending on the context, are often considered acts of terrorism. CBRNE events often involve agents or materials that can cause damage or harm over a wide area. Chemicals may be dispersed by wind, biological agents may be passed from one person to another through infection, and nuclear radiation can affect every organism within a given radius. This means that the emergency scene may be large, and there are typically multiple casualties. Breathing more than 30 times per minute Breathing normal, but radial pulse absent Breathing normal, radial pulse present, but level of responsiveness abnormal DEAD/NON-SALVAGEABLE (BLACK/GREY) No respiration Types of Agents CHEMICAL AGENTS Chemical agents are substances that adversely affect the body through chemical action. They are grouped into five general categories (Table 21–2). BIOLOGICAL AGENTS Biological agents affect the body through biological action. They can be broken down into three general categories (Table 21–3). MULTIPLE-CASUALTY INCIDENTS TABLE 21–2: CATEGORIES OF CHEMICAL AGENTS 362 CATEGORY DESCRIPTION EXAMPLES Nerve agents (organophosphates) Most toxic of all chemical agents: Can cause death within minutes of exposure Disrupt nervous system, resulting in loss of cardiac and respiratory function Deployed as liquid or vapour Sarin Tabun Blood agents Cause asphyxiation by interfering with the body’s use of oxygen Deployed as solid or gas Cyanide Blister agents (vesicants) Cause blisters on affected skin and mucous membranes If inhaled, cause serious respiratory tract injuries Deployed as vapour or liquid Mustard gas Choking agents (pulmonary agents) Cause pulmonary edema, which can lead to asphyxiation Often used in industrial applications Deployed as liquid or vapour Chlorine Phosgene Riot control agents (crowd management agents) Temporarily impairs the performance and normal function of the target Causes localized irritation of affected areas Considered non-lethal Deployed as droplets or powder (for more information, see Crowd Management Agents on page 274) Pepper spray Chloroacetophenone TABLE 21–3: CATEGORIES OF BIOLOGICAL AGENTS CATEGORY DESCRIPTION EXAMPLES Viral agents Non-cellular organisms that depend on a host organism for survival Smallpox Viral hemorrhagic fevers (VHF) Bacterial agents Single-celled organisms that invade host tissues and/or release toxins in the body Anthrax Tularemia Toxins Poisons produced by living organisms (plants, animals, or microbes) Exposed patients are not infectious Ricin Botulism Methods of Dissemination Personal Protective Equipment The goal of a CBRNE event is often to cause mass casualties or wide-scale destruction. Therefore, the harmful agent used in the attack is often disseminated over a wide area. Dissemination methods fall into four categories: 1. Mechanical action 2. Chemical reaction 3. Pneumatic devices 4. Explosive devices Personal protective equipment, or PPE, is designed to provide protection from serious illnesses or injuries as a result of exposure to hazards that may be chemical, radiological, physical, electrical, or mechanical. PPE should be used in conjunction with exposure-control procedures and equipment. Examples of PPE include respirators, protective clothing, eye and hearing protection. Based on the hazard, the level of PPE required will vary: No single combination of protective equipment and clothing will meet the need of all CBRNE incidents (Figure 21–3). MECHANICAL ACTION Mechanical action uses simple physical processes to disseminate a substance. This may involve breaking a glass vial, for example, or simply placing a substance in an open container where it will naturally disperse (e.g., in an office building’s stairwell). CHEMICAL REACTION A chemical reaction occurs when two or more substances are mixed to produce a more hazardous compound. This may be done manually (i.e., by stirring them together) or using another device (e.g., a timer could activate a switch that allows the chemicals to mix). Pneumatic devices use pressurized gas to disseminate a harmful substance. This may be an improvised or repurposed device, or it may be purpose-built. EXPLOSIVE DEVICES On their own, explosive devices can cause property damage and blast injuries to people nearby. They may also be used effectively as dispersal devices for other agents. Figure 21–3: The risk of contamination depends on the nature of the incident and dictates the level of PPE worn by responders. MULTIPLE-CASUALTY INCIDENTS PNEUMATIC DEVICES 363 Scene Assessment When confronted with a CBRNE incident, follow your usual scene assessment procedure, paying special attention to the following guidelines: Identify an escape route in case the situation suddenly deteriorates. Pay particular attention to casualties (number, location, and severity of signs and symptoms). Warn other responders of potential hazards at the scene. Be aware of secondary devices and the possible presence of a perpetrator. Approach the scene from an uphill and/or upwind direction. This allows toxic materials to flow or be blown away from you rather than towards you. Elevation prevents the formation of pockets of toxic vapours and gases that are heavier than air. Casualties with minor injuries should receive clear and specific directions on where to go and what to do. They should be directed to move to a designated gathering point (e.g., the entrance to the decontamination area). Casualties should keep a distance of approximately 5 metres (16 feet) between themselves and others to further reduce the risk of contamination. Inner and outer perimeters should be quickly established around the affected area (Figure 21–4). This can be done by the first responders on scene and will reduce the risk of contaminating additional persons. Directed first aid is the care a patient provides to him- or herself while being directed by another (more qualified) person. This is useful in situations where patients cannot be reached by responders, or are contaminated to an extent that makes it unsafe for responders to provide care. Many lifesaving interventions, such as applying pressure to an external hemorrhage, are easy to describe in simple terms. Directed first aid may also be performed by one patient on another. r pe eter 900 m (2,9 t ime e r 1 00 m 53 ft. ) (3 ft.) I nn er e ut erim rp 28 Triage in a CBRNE Incident O DIRECTED FIRST AID The outer perimeter or security perimeter is established beyond the inner perimeter to create a secure working area for responders and prevent unauthorized access to the contaminated area. MULTIPLE-CASUALTY INCIDENTS Contaminated casualties must be controlled and contained to prevent the spread of the contamination. Any patient in a contaminated area should be considered contaminated until they can be proven otherwise. Do not approach or touch a potentially contaminated patient without wearing appropriate PPE. Establishing Perimeters The inner perimeter or safety perimeter should be at least 100 metres (328 feet) from the source of contamination (in an enclosed environment) or 900 metres (2,953 feet) from the source if it is outdoors. These are minimum values and may be adjusted if necessary (e.g., if strong winds are visibly dispersing an agent beyond the perimeter, the perimeter should be extended). 364 Control of Contaminated Casualties Contaminated zone Because patients in a CBRNE incident may be contaminated, their initial assessment should be performed by specialized personnel equipped with appropriate PPE. Without PPE appropriate to the situation, assessment and care should only be attempted once the patient has been decontaminated. Figure 21–4: Establish an inner and outer perimeter around the affected area as soon as possible. DECONTAMINATION PROCEDURES Transporting CBRNE Patients A patient contaminated during a CBRNE event must be decontaminated to prevent further harm to the patient and to reduce the risk of contaminating others. A patient should not leave the CBRNE scene without being decontaminated. A CBRNE event poses special challenges for patient transportation. In some cases, the risk of contamination makes transportation impossible until the patient has been thoroughly disinfected. In other cases, the threat of contamination may be low and should be balanced against the serious risks of delaying transportation for a patient in critical condition. Emergency wash-down procedures allow responders to perform a rapid preliminary decontamination of a patient with resources that are readily available. While EW can significantly reduce the signs and symptoms of exposure to CBRNE agents and may save the lives of the patients involved, it is not an alternative to proper decontamination. Patients should still be formally decontaminated once the facilities to do so are available. Patients can be instructed on the EW technique from a distance if responders lack the appropriate PPE or the scene is not safe to approach. EW basically consists of carefully removing all clothing and washing skin thoroughly with soap and water (if available). One simple method is to spray water over patients with a fire hose equipped with a fog nozzle. Direct patients to follow these general steps: 1. Carefully remove clothing and personal items, being mindful to avoid contaminating the skin beneath. Casualties may be able to assist one another. 2. Place removed items in double plastic bags, if possible. These should be collected by qualified personnel. 3. Walk through the spray of water with head back and legs and arms spread. 4. Wash from the top down, using soap if it is available. Patients should avoid swallowing water or touching their faces with their contaminated hands. 5. Proceed to the designated holding area to await decontamination. Another challenge when transporting patients from a CBRNE event is the number of patients: In a large-scale emergency with dozens or even hundreds of patients, the number of patient transportation vehicles may be insufficient for the scale of event. In some cases, it may be possible to use public transit buses or school buses to transport patients, especially those with minor injuries, reserving ambulances for patients with more urgent complaints. In many jurisdictions, decisions about transporting patients from a CBRNE event will be directed by the public health authority. Psychological Impact of CBRNE Events A CBRNE event can have devastating psychological effects on responders. In addition to witnessing the suffering, death, and damage that can result, there is the further complication of knowing that they are the result of the deliberate actions of a human being. For this reason, CBRNE events can be especially traumatic, even when compared with other mass-casualty incidents such as natural disasters. As with any mass-casualty incident, a responder must do everything possible to help while realizing that even a perfectly coordinated and executed response may not be able to save every patient. CBRNE events are also unfamiliar to most responders, leading to fear and self-doubt both during and after the event. When this is combined with the pressure to act rapidly to save lives, the psychological pressure becomes very high. MULTIPLE-CASUALTY INCIDENTS Emergency Wash-Down (EW) 365 Any responder involved in a CBRNE response should receive counselling and support once the incident is resolved, as the risk of critical incident stress (CIS) is very high. MULTIPLE-CASUALTY INCIDENTS Consider the following guidelines when responding to a CBRNE event: If you begin to feel overwhelmed, control your reactions by breathing slowly and regularly. 366 Focus on the task that you are performing (while monitoring the scene for hazards). Take breaks during a prolonged response. If possible, move away from the scene. Eat regularly and stay hydrated. Support your fellow responders. Watch for signs of stress, and ensure that those around you follow proper protocols and procedures to keep themselves and others safe. SUMMARY THE START SYSTEM Minor Colour code: green Patients with minor illness or injuries Have patients move to designated area for evaluation by arriving medical personnel Delayed Care Colour code: yellow Respiration, circulation, and LOR present as normal in these patients; however, they cannot move Immediate Care Colour code: red Patients with illness or injuries that put them in the rapid transport category Dead/ Colour code: black or grey Non-Salvageable Patients who are found obviously deceased or who are initially without respiration but attempts to open and clear airway are unsuccessful Emergency  Wash-Down (EW) Instruct contaminated patients to: 1. Carefully remove clothing and  personal items; patients may be able to assist one another. 2. Place removed items in double  plastic bags, if possible, to be  collected by qualified personnel. 3. Walk through the spray of water with their heads back and their legs and arms spread. 4. Wash themselves from the top down, using soap if it is available, and avoid swallowing water or touching their faces with contaminated hands. 5. Proceed to the designated holding area to await decontamination. IM 0 I 0 I II III II III CBRNE Events If you begin to feel overwhelmed, control your reactions by breathing slowly and regularly. Focus on the task that you are  performing (while monitoring  the scene for hazards). Take breaks during a prolonged  response; eat regularly and stay  hydrated. Support your fellow responders. Chemical, Biological, Radiological, Nuclear, Explosive (CBRNE) MULTIPLE-CASUALTY INCIDENTS IV 367 368