While paper triage tags and clipboards of notes have the undisputable advantage not to malfunction or require batteries or electricity, paper-based methods are time-consuming, labor intensive, and prone to human error.34,35 Disadvantages of paper tags compared to ePTS include:
Bad weather conditions and illegible handwriting can diminish the usefulness of paper systems.13,36,37
The amount of information that can be recorded is limited due to lack of space.8,13,37 The recorded information is often ill-structured.32
A manual count of triaged and tagged patients is necessary to provide a situational overview.8
Paper triage tags do not provide information about the dynamic location of the patient.8,11
Some triage tag systems do not easily allow changes to the triage category, particularly improvements.8,13 As triage is a continuous process, a system to document reassessments is necessary.38
Prioritization of multiple patients within a single triage category is not provided by triage tags.8
Monitoring of vital signs requires additional actions or equipment.
Although paper tags are relatively inexpensive, it is costly to maintain updated versions; in addition, triage tags vary widely in manufacture design and are not standardized, making training and interoperability difficult.37
Data may be lost during transport of the victim.37
Information on the tags is not secure and may be unintentionally disclosed, thereby violating patient privacy protection rights.37
Paper tags are problematic in chemical, biological, radiological, and nuclear (CBRN) situations; it is difficult to complete tags while wearing personal protective equipment (PPE), and they are generally not sufficiently durable to withstand wet decontamination.39
These weaknesses of paper-based triage and documentation systems are further aggravated by the inherent unreliability of communication systems,37 as observed previously.
As expected, direct comparisons between paper and electronic systems – mainly by means of exercises – usually find advantages of ePTS in regards to tracking and localization. ePTS data capture and safety features are generally described as at least as good and reliable as those for traditional paper-based systems. Researchers published such findings for the following ePTS prototypes:
WIISARD (Wireless Internet Information System for Medical Response in Disasters);30,37,40
DIORAMA (Dynamic Information Collection and Resource Tracking Architecture) – where an average reduction of 30% in evacuation time was found;41 and
AID-N (Advanced Health and Disaster Aid Network) – where the system was shown to triple the number patients that could be triaged over a given time period.11
A properly designed computerized system can improve data capture and reduce inaccuracies.19 ePTS were shown to reduce missing and duplicated patient identifiers. Rapid access to information regarding numbers and status or triage classification of casualties facilitated decision making.30,17 When applied in exercises, ePTS improves evaluation opportunities by providing more objective data and better comprehensive event reconstruction as compared with paper tags.42
Several groups have developed systems designed to improve victim tracking and the management of medical information in mass casualty events by instant access to identity and location information. Lenert30 and Pate2 provide excellent overviews.
The technologies applied comprise barcode readers, RFID, global positioning system (GPS), and miniaturized vital signs monitors; all of which are linked by wireless network technologies. These solutions will be highlighted during the discussion of technical issues.
Smartphones have become ubiquitous. At times, they have led to the design of real-time, ad hoc medical information management systems. After the Haiti earthquake, such an improvised system succeeded in improving disaster victim tracking, triage, patient care, facility management, and theater-wide decision making.1
Governmental Guidance
Guidance documents from the United States are the most readily available and will be used as examples. In a discussion about Hurricane Katrina, Pate notes that the “failure of the nation to adequately track victims … has been identified as a major weakness of national and local disaster preparedness plans” and prompted government and private industries to “acknowledge that existing paper-based tracking systems are incapable of managing information during a large-scale disaster.”2
The detailed U.S. National Response Framework of 2008 only briefly mentions “registration and tracking of evacuees” as a capability necessary to fulfill Emergency Support Function 6 (ESF 6), Mass Care, Emergency Assistance, Housing, and Human Services. While not explicitly described in ESF 8, Public Health and Medical Services, the list of functions implies that tracking is an essential capability for this area as well.
In 2009, the Agency for Healthcare Research and Quality within the U.S. federal government published “Recommendations for a National Mass Patient and Evacuee Movement, Regulating, and Tracking System.”3 This document recommended the creation of a national system for use during a multi-jurisdictional mass casualty or evacuation incident. The goal of the system would be for “locating, tracking, and regulating patients and evacuees”3 (with “regulating” meaning to ensure transport on an appropriate vehicle to an appropriate location), as well as to improve decision making regarding transportation, resource allocation, and incident management, and to facilitate family reunification. The authors asserted that the number of jurisdictions using patient tracking systems was unknown at that time (but certainly a small percentage), as there were few compelling reasons for using these systems on a daily basis.
Tracking people between any pair of locations or monitoring movements of patients from an incident scene to a receiving hospital was regarded as “not unlike the processes employed by package delivery companies,”3 where each package must be uniquely identified and tagged (e.g., barcoded), and its whereabouts reported into a central database. Policymakers proposed using the same processes to transmit a unique identifier and the triage category for people being evacuated from a disaster zone. The system must account for the fact that, unlike packages, people can also move of their own volition.3 Figures 28.3 and 28.4 provide examples of two such systems.
Authorized users could access tracking data for a variety of purposes. For example, to assist with casualty distribution, emergency operations center personnel can monitor and track casualties and the number of patients transported to each hospital. Hospital personnel can track incoming casualties and prepare for specific casualty types. An open website can be established so that the public can query the database to determine the location of loved ones.3
Similar considerations for patient tracking were published after the events of September 11, 2001, in the United States.43 These defined the following goals:
Ability to monitor a person’s progress through the system in order to keep track of patient locations and treatment updates;
Capability of linking into a common operational picture to assist with deployment of emergency responders;
Ability to attach to patients;
Capability of identifying triage priority, clinical status and personal information, and remotely transmitting it in real-time to a common operational picture available to commanders and command centers, hospitals, and other key personnel; and
Ability to provide command centers with an operational picture containing real-time information about the local system’s resource status and patient care capabilities.
Solutions for Patient Tagging
Unique Identifiers
A unique identifier needs to be assigned for every registered person. Developers have proposed creation of such identifiers based on patient-specific data (e.g., date of birth, name, and sex), but most systems use location-specific alphanumeric numbering similar to the numbers assigned to paper triage tags.5,19
The numbering used within the tracking system should be compatible with hospital registration systems. At a minimum, the system should be capable of linking the identification number with other numbering systems used in healthcare (e.g., HL-7 identification numbers) or administration (e.g., social security or insurance numbers). Standardized tagging would simplify and facilitate efficiency for inter-hospital transfers.16 Attempts to capture information directly from patients or their personal documents (e.g., driver’s license) and use this as an identifier have not been successful.
Barcodes
One of the simplest ways to upgrade paper triage tags to ePTS would be
1. to amend the tags with a barcode;
2. to supply responders with handheld devices for barcode scanning and data entry; and
3. to connect these devices via a wireless network to a central data storage and viewing unit.36
Utrecht Emergency Hospital personnel developed such a system.19,23 The decision to use barcodes as an interactive non-keyboard method was the result of the proven reliability of barcodes, their cost-effectiveness, and the prior use of similar technology in the hospital.
Between 2002 and 2004, researchers developed the Victim Tracking and Tracing System (ViTTS) in the Netherlands. ViTTS uses injury cards (triage tags) with a barcode that links to a unique identification number. Emergency workers scan the barcode with a handheld device linked to a local network at the scene. The first responding ambulance personnel create a wireless network equipped with a mobile access router that establishes a secure, high-capacity data system. As soon as data are entered, they are viewable by all authorized users. Once the victim’s identity becomes known, the barcode number can be coupled with the social insurance number.5
The emergency tracking system implemented in the St. Louis area of Missouri uses similar barcoded bracelets scanned by Wi-Fi or cellular-enabled devices.44 Data are also shared with the American Red Cross as a designated disaster relief organization.
Some authors suggested that barcoded, pre-event printed wristbands could aid in triage and treatment and in reporting victim information to command centers; and that the universal implementation of such a system would augment surge capacity.16
Another model proposed the use of barcode stickers, which are printed by using field devices and are resistant to harsh environmental conditions. These stickers could be attached not only to the triage tag, but also to the patient’s body and belongings.32 Attaching stickers to triage tags before an incident occurs is another option.36
Radio-Frequency Identification (RFID)
RFID technology is not new to the medical sector. It has been used for many purposes to enhance patient safety (including patient identification, medication safety, or surgical process management) and hospital efficiency (by tracking supplies and equipment).45
An RFID system typically consists of a tag, a reader, and some sort of data processing equipment, such as a computer. Passive RFID tags store only a tiny amount of data and are powered by the energy emitted from the reader; their range is limited to about a meter. Active RFID tags have a battery and continuously transmit and receive signals. They can store vast amounts of data, have a lifespan of several years, and can be read over distances up to 100 meters.46
One ePTS prototype using RFID technology is the Dynamic Information Collection and Resource Tracking Architecture or DIORAMA. Every patient in the disaster scene is tagged with a DIORAMA electronic tag (D-tag) showing the severity of the patient’s injury (red, yellow, green, and black) in the same way as paper tags. Moreover, each emergency responder (e.g., paramedic, firefighter, police officer) and resource is also equipped with a DIORAMA tag.41 All these active wristband RFID tags transmit information to a server via a wireless network. For patients, this time-stamped information includes the severity of injury and current location. This information transfer operates automatically without victim or staff intervention.
Responders can carry readers or position them at set locations such as casualty collection points. They have a range of up to 100 meters.47 While these devices have proven successful in exercises, the authors concede that the expense, size, and complexity of the wristband devices may make them impractical to distribute in adequate numbers to monitor all victims of a large-scale disaster.41
Other RFID-based prototype systems include SOGRO (Sofortrettung Großunfall) in Germany48 and the Wireless Internet Information System for Medical Response in Disasters or WIISARD in the United States.30,40 The developers of WIISARD adopted RFID technology rather than barcodes because barcode reader performance can be significantly impaired if lighting is inadequate.37 In the Nordic countries, investigators developed another RFID-based ePTS prototype that uses mobile phones with integrated RFID readers as field terminals.17
The U.S. military developed an integrated software-hardware system called MASCAL to enhance management of resources at a hospital during a mass casualty situation. MASCAL uses active RFID tags to track patients, equipment and staff.18
Intelligent Tags
In addition to signal transmission for tracking and location, the WIISARD RFID system displays the victim’s triage status in an easily visible way by use of signal lights. These devices were primarily designed to be usable in CBRN environments and are therefore water resistant so that they will continue to function if the patient undergoes decontamination.30 These intelligent triage tags automatically record selected vital parameters like oxygen saturation;49 the tag also serves as an electronic medical record.
The Trauma Patient Tracking System (TPTS), also a prototype, supplies all patients with a device that continuously reports their locations. They are connected to a base station via a wireless network. When out of range, the tag is capable of logging its own positional history and later uploading these data to the server once connectivity is restored.50
Wearable Sensors
Another initiative is the combination of ePTS (with the localization or tracking function) with wearable vital sign sensors. This strategy should alert responders to any deterioration of patient status so that reassessment can be performed.9,13
Several groups have explored the option of using “motes” (a type of low-power and low-cost computer for sensor networks) for application in disaster management.30,51,52 In the CodeBlue project, a wireless pulse oximeter and a wireless two-lead electrocardiogram (EKG) were combined to a sensor mote collecting heart rate (HR), oxygen saturation (SpO2), and EKG data and transmitting those data over a short-range (100 meter) wireless network.52
Researchers developed prototype electronic triage tags for the Advanced Health and Disaster Aid Network (AID-N).These tags provide the following functionalities: triage status display (with colored lights), vital sign monitoring, location tracking, and alarm signaling.8,9
None of the mentioned prototypes have been introduced into routine practice. Cost to implement such a system, with hundreds or thousands of wearable sensors, can be prohibitive. Automatic display of triage status based on measured parameters is also non-trivial.
ePTS Functions and Limiting Conditions
Data Entry
The first-time patient data can be entered into the system is at the initial contact with medical care. Irrespective of the technology used to assign the unique patient identifier (paper tags, barcode wristbands, or any ePTS), manual data entry is necessary, either on the tag itself or into the handheld device connected to the ePTS network. Data entry is labor intensive and time-consuming; therefore, adequate human resources must be allocated. This can be challenging, as emergency responders have been shown to prefer to care for patients rather than take time to enter data.1 Responders should consider unconventional solutions such as use of scribes, volunteers, or members of organizations uninvolved in initial patient assessment.
Multiple Locations for Data Entry
Data entry requirements to register a new patient should be kept as simple as possible. The system should allow amending data at a later point of time, when more resources become available.3 ePTS should have capacity to include patients lacking identifying information (e.g., “unknown male, about 40 years old”).
Efficient ePTS must allow data entry at multiple points and from multiple users. While historical data should be preserved as new information is added, the system should be designed to automatically limit duplication of data that would unnecessarily enlarge the database. There should be a clear and simple method for data reconciliation for conflicting data set entries. Furthermore, there should be an effective process for finding and merging multiple entries if patients have been registered with different identifier numbers at different locations.
Amount of Data vs. Essential Data Set
Several recommendations for a minimal data set for ePTS have been published, usually differentiating between mandatory basic data fields and desirable additional information elements.53
Mandatory or essential data typically consist of elements like triage tag number or name (if available), sex, date of birth or age, current location and transfer destination, triage category, and initial condition/chief complaint.3 The system should be designed to capture the initial location and also track sequential locations by having multiple time-stamped data fields.
The “additional information” data field may include such elements as: more detailed medical and treatment information, additional personal information (including full name, contact information or telephone number, most current address or home zip code, social security number or equivalent), and patient permission for information sharing. Some authors suggest including distinguishing characteristics of the individual like eye color, birthmarks, tattoos, and scars.54
As technological possibilities expand, it is important to keep data entry requirements as simple as possible so that personnel can perform the task with little or no training and in a minimal amount of time.
Whether using high-tech or low-tech solutions, it is prudent to reduce the amount of information being collected. The more data collection is requested from responders, the less compliant responders will be, and the more data quality will decrease and propensity for errors will increase. In addition, the more data fields required, the slower the data will be transmitted via the networks.
Tracking systems should collect only the data necessary to reconstruct the events surrounding the incident and document medical histories sufficient to facilitate patient care and protect against malpractice claims. It would be a waste of time and resources to collect excessive data that will have no future use. ePTS have a specific purpose and are not intended to replace routine medical records.
The type of incident determines the needed frequency of data updates. For example, family assistance centers receiving requests for information might require frequent data updates every 30 or 60 minutes.20,21 Conversely, policymakers at a national level might only require daily updates. For conflict situations with a search for missing persons, such as by the Red Cross Tracing Services, much longer update intervals may be acceptable.55