It’s a Friday evening, a full moon is glowing in the night sky, and the ED is busting at the seams like a subway car at rush hour. Just when you’re wondering how you’re going to admit one more person, a psychiatric patient is transferred from another facility, 10 walk-in patients remain waiting in the lounge, three more patients walk through the ambulatory entrance, and two ambulance patients are brought through the back door. Do any of these patients need to be seen immediately? Which patient should receive the next available bed? Is it safe to put the ambulance patients out in the waiting room? This module reviews the major methods and types of triage within the context of the ED, with an emphasis on five-level triage systems. A reliable and valid triage system can help you effectively care for your ED patients.

The battlefield connection

The word triage is derived from the French word trier, which means to pick, choose, or sort. The art of triage finds its roots in the military medicine of the mid-1800s.¹ A French military physician, Dominique-Jean Larrey, was the first to say that the most severely injured soldiers should receive care first, without regard to rank.² Up until that point, battlefield treatment tended to be prioritized based on rank.

In 1854, during the Crimean War, Russian military surgeon Nikolai Ivanovich Pirogov delineated triage categories that closely resemble the categories we still use today.² Pirogov named four triage categories:

• Immediate — those with hemorrhage, chest and abdominal wounds, and amputations
• Delayed — those not in immediate danger of dying
• Nonurgent — those with lesser injuries
• Comfort — which he defined as “for the priest”²

This type of triage is still used in today’s military www.uihealthcare.com/depts/medmuseum/wallexhibits/ems/triage.html and in disaster and mass casualty incidents. 

EDs also use triage to prioritize patients. If the ED had unlimited resources and unlimited capacity www.ena.org/about/position/ PDFs/FB9331058E384AF0BADBCC75CE7B25E4.pdf, staff could simply take patients on a first-come, first-served basis. However, because of constraints on resources and available treatment areas www.aha.org/aha/content/2004/PowerPoint/EDDiversionSurvey 040421.ppt, staff must triage patients to ensure that the sickest patients receive the most efficient and timely resources.³

Methods of Triage 

Regardless of the type of triage system used — two, three, four, or five level — different methods of triage exist. The most common methods are traffic director, spot-check, and comprehensive.⁴

The traffic director — also known as “quick look” — is a fast initial triage method that is typically used before a more comprehensive method. Using this method, the triage nurse makes an immediate decision based on a limited visual and verbal examination of the patient. For example, a patient walks into the ED with his arm wrapped in a bloody towel. The triage nurse asks, “What did you do to your arm?” The patient states, “I cut my arm really bad with a circular saw.” The nurse triages the patient to the trauma area. Conversely, if a patient walks into the ED without any outward signs of distress and states he has diarrhea, he is directed to the waiting room. The drawback to the traffic director triage method is that only obvious emergencies are detected.

The next method of triage is the spot-check. In this method, the triage nurse performs a focused interview and physical exam based on the patient’s complaint. If the patient has a sprained ankle, the triage nurse will not ask about medical history or medications, nor perform any physical exam other than examination of the ankles and lower legs. This method is quicker than the comprehensive method and is more sensitive to covert problems than the traffic director method. The drawback of this method is that it may not uncover associated problems at triage, such as hypertension, or pertinent medical history, such as hemophilia.

The comprehensive method is considered the most advanced and is endorsed by the Emergency Nurses Association http://enw.org/solutions.htm — search for “Five Tier Acuity Lecture.”.⁵

It’s the conceptual framework for most of the five-level triage systems.⁵ The comprehensive method includes a patient-focused interview and examination, past medical history, list of medications, and vital signs. This method takes the longest of the three methods but derives the most information.

The most widely accepted standard for triage is that it be completed within five minutes.⁴ This can certainly be done, even when performing a comprehensive triage. The challenge comes when multiple patients are awaiting triage. If you have eight patients awaiting triage and each patient takes five minutes, is it acceptable that the eighth patient’s triage is completed 40 minutes after his arrival?

The three methods should be viewed as a continuum. The key is to move along this continuum, from traffic director to comprehensive, in an effort to provide the best triage possible. At times, the triage nurse will have to sacrifice some sensitivity in triage for speed, ensuring that all patients are triaged as quickly as possible.

The simplest type of ED triage is the two-level system. This system triages patients into two categories: emergent, or patients requiring immediate intervention, and nonemergent, patients who do not fit into the emergent category. Because of overwhelming limitations, the two-level system has been replaced with the three-level system. 

The three-level system is the most popular type of triage in the United States.⁵ In 2004, 69% of U.S. EDs used a three-level triage system, nearly 12% used a four-level system, 3% used a five-level system, 4% used some sort of system not previously classified, and, remarkably, nearly 12% of EDs used no triage scale at all.³

The three-level system classifies patients into the following categories: emergent — those requiring immediate interventions; urgent — those requiring care to prevent deterioration or complications; and nonurgent — those who can wait for treatment without significant deterioration or complication. A drawback of this method is that the vast majority of patients qualify for the urgent category. 

On a normal day in an ED that cares for 100 patients on average, 10 of those patients may be emergent, 30 may be nonurgent, and 60 may be urgent. How is it possible to determine which of these patients needs care first?

In an attempt to overcome the shortcomings of the three-level triage system, some hospitals moved to a four-level system, where the most critical patients have conditions categorized as “life-threatening.” These patients are the sickest of the sick and usually require immediate resuscitation. The three lower levels of patient classification in the four-level system remain the same as the three-level: emergent, urgent, and nonurgent. The difference in the two systems is in the type of patients placed in each level. The emergent category in the four-level system now has the sickest of the sick removed (these patients are placed in the “life-threatening” category) and attempts to pick up some of the sicker patients who would be placed in the urgent category in the three-level system. The four-level system has never been widely accepted in the ED community. The reason may lie in the possible confusion between the emergent and urgent levels in the three- and four-level systems.

In the past decade, the five-level triage system has become the standard in Australia, Canada, and the United Kingdom.^3,5,6 In the past few years, this system has also gained popularity in the United States. One of the primary reasons for this popularity is the policy statement www.ena.org/about/position/PDFs/2EC50419F5 B04D1190496C212EEF72DF.pdf from by the Emergency Nurses Association and the American College of Emergency Physicians, which says, “ACEP and ENA believe that quality of patient care would benefit from implementing a standardized ED triage scale and acuity categorization process. Based on expert consensus of currently available evidence, ACEP and ENA support the adoption of a reliable, valid, five-level triage scale.”⁷

EDs often assign numbers to the triage levels previously discussed. The standard is to assign “1” to the highest level and “2,” “3,” “4,” or “5” to the lower levels. The problem is that this convention often conflicts with other scales, such as emergency medical service priorities and level of care charges, which tend to use “1” for the lowest priority or acuity.³

Trends around the world

One of the first five-level triage systems used is the Ipswich Triage Scale, published in 1989 by an Australian ED physician.6 The Ipswich Triage Scale continued to evolve until 1994, when Australia implemented it as the National Triage Scale (NTS). This scale is now called the Australasian Triage Scale (ATS) http://enw.org/AustralianTriageScales%20Policy.pdf.⁶ Studies show that with each level of triage in the ATS, predictable associations exist; for example, the higher the triage acuity, the higher the percentage of admissions, the higher the mortality, and the more resources used.^3,8

In the United Kingdom, the Manchester Triage Scale, which is based on the NTS, has been used by many EDs in Great Britain since 1997.³ This system uses 52 algorithms to assist in assigning a triage level.

Again, based on the Australian NTS, Canada developed the Canadian Triage and Acuity Scale for Emergency Departments (CTAS) www.caep.ca/template.asp?id=B795164082374289 BBD9C1C2BF4B8D32 in the mid-1990s.⁶ In 1997, the Canadian Institute for Health Information http://secure.cihi.ca/cihiweb/ dispPage.jsp?cw_page=home_e required all EDs in Canada to report their triage data using the CTAS.³ The CTAS has been heavily researched over the past 10 years and has been shown to be a valid and reliable predictor of ED resource utilization.^9,10

Australia, Canada, and the U.K. adopted five-level triage systems as a national standard.¹¹ However, the United States has been slow to adopt the five-level triage system. As stated earlier in this module, only 3% of U.S. EDs were using five-level triage systems in 2004.³

In 1999, two U.S. ED physicians implemented the Emergency Severity Index (ESI) www.ncbi.nlm.nih.gov/entrez/query.fcgi? cmd=Retrieve&db=PubMed&list_uids=11157294&dopt=Abstract at two university hospital EDs.⁴ The ESI is unique in that it considers the number of resources — such as radiology procedures and laboratory tests — the patient will use.^3,4 Conversely, the ATS, CTAS, and the Manchester Triage Scale all seek to determine how long the patient waits before being treated.

In 2000, using input from clinicians at the two university hospitals where the ESI was created, the index was revised to include pediatric criteria. However, not much evaluation and research have been conducted on the reliability and validity of five-level triage systems in pediatrics.³ This subject requires more evaluation by EDs that care for many pediatric patients.

The system was further refined in 2001, resulting in ESI Version 3.4 The fourth version of ESI www.ahrq.gov/research/ esi, published in 2005, is quickly becoming one of the most frequently used five-level triage systems in the United States.

Using ESI, triage decisions are first based on the stability of the patient and the potential for immediate life threats to the patient. This encompasses all Level 1 patients and many Level 2 patients. Next, the triage nurse considers the number of resources the patient is expected to use to determine if the patient fits into Level 3, 4, or 5.

The triage nurse uses a four-question algorithm to initially assess the patient. The first question asks, “Is the patient dying?” If the answer is “yes,” the patient is categorized as Level 1. If the answer is “no,” the next question is, “Should the patient wait?” If the answer is “no,” the patient is categorized as Level 2. The patient should not be kept waiting if there is increased pain, changes in mentation, or other signs that indicate the patient may be at high risk for medical complications. Based on these questions, the triage nurse then predicts the resources required to get the patient to disposition. If no resources are predicted, the patient is a Level 5. If the prediction is one, the patient is a Level 4. If the patient is predicted to require two or more resources, the patient is a Level 3. The final question is related to vital signs. An alteration in vital signs can move a patient from Level 3 up to Level 2.¹²

Which five-level triage system is superior? The superior five-level triage system is the one that works best for the staff and the facility. Each of the five-level triage systems is proven reliable, valid, a good predictor of resource utilization, and better than three- or four-level systems.^3,6,8-11,13 Although the ENA and ACEP recommend a five-level system, they do not specify which one. The ACEP/ENA Five-Level Triage Task Force did say that either the CTAS or the ESI is a “good option.”³ Some hospitals develop their own system by blending the CTAS and the ESI.¹⁴

The art of triage

EDs account for a little more than half of all sentinel events reported to the Joint Commission www.jointcommission.org. Most of these events are related to delays in care.¹⁵ If our triage system is not reliable in getting the right patient to the right care in the right time, we have an unsafe system that can lead to delays in care and overall inefficiency.⁶

Your facility’s most experienced nurses should be performing triage. Triage is an art. Clinical judgment and critical-thinking skills are required.³ Also, remember that any patient triaged to the waiting room should be re-evaluated within two hours of the initial triage and continually reassessed according to the patient’s acuity.¹ Just because a patient is initially triaged as a Level 4 does not mean that the patient won’t progress to a Level 3, 2, or 1 given a long enough wait.

You must evaluate your triage effectiveness. You can do this by observing actual triages, reviewing charts, or through triage simulation. Using your two best triage nurses as the gold standard, determine how much they agree with the triage level assigned by others. There are three possibilities. First, the triage level assigned can agree with the gold standard. This is the desired outcome. The second possibility is overtriage. This occurs when the nurse categorizes a patient to a higher level category than the gold standard. Although this is safer for the patient, it can overutilize ED services and overwhelm the ED, leading to an overall unsafe condition. The third possibility is undertriage. This occurs when the nurse assigns the patient to a lower level than the gold standard. This may lead to an unsafe situation in which a patient does not receive the right care in the right amount of time. Studies show 11% to 28% of patients are overtriaged and 8% to 14% of patients are undertriaged.^6,12 Other reports show 70% to 99% concordance, or agreement, with the gold standard.^11,16 Many studies evaluate concordance based on the assigned category being within one level of the gold standard.

You should also evaluate your system’s validity. Does the current triage level accurately predict the amount of work needed or the amount of resources required? No one clear method exists to evaluate the validity of triage. Administrators and researchers examine relationships among hospital admission rates, mortality rates, level of care charges, workload measurements, and triage levels.³ For example, you may expect to see a rise in the number of admissions as the triage levels increase.^11,12 This is an important measure because 45% to 65% of all hospital inpatient admissions originate in the ED.¹⁷

How can technology help? 

By standardizing a reliable and valid five-level triage system, we can use technology to help us with strategic and operational decision-making. Using simulation programs, historical triage data can be entered to help identify trends in acuity, predict resource requirements, and examine the effects of opening and closing beds or streamlining processes.¹⁷ New technologies — such as computerized patient tracking systems, computerized charting, personal communication devices, and simulation software — may be used to improve triage effectiveness and the triage process as a whole.⁵

Some computer decision systems use algorithms and information entered by the nurse to determine appropriate triage levels. These systems can be somewhat rigid, for example, requiring input of vital signs before determining a triage level.¹¹ While these computerized decision tools can be helpful, they still require a trained and knowledgeable human to enter the information. Also, the triage nurse must always be able to override the system and increase the triage level if necessary.¹¹

Once a state, region, or country standardizes to a single five-level triage system, technology can be used to centralize the triage data. This information may then be used by the public health community to examine trends and effects related to access to health care.

Implementation

You have decided to implement a five-level triage system after reviewing the literature and understanding the ENA and ACEP guidelines. What steps must you take to implement your plan?

1. Form a five-level triage steering committee. This committee should include ED management, the ED medical director, and your most knowledgeable and skilled triage nurses and paramedics.

2. Research the major five-level systems and determine which one is right for your facility, or develop your own system by combining components of the existing systems. Be aware that the latter choice will not help to further a national standardized system.

3. Train your ED staff and ED physicians to the five-level triage system. Be sure to allow ample time for training. This is crucial because inadequate training could prove disastrous. This doesn’t mean that your staff must sit in a classroom for hours on end. Both Web-based and computer interactive training methods are gaining acceptance and are effective in teaching triage systems.^12,16

4. Implement the new system. Understand that initially, the new triage system may take longer for the staff to use until they become accustomed to it. Also, make sure that all ED staff and ED physicians are knowledgeable about the change in systems.

5. Evaluate the new system. If some aspect of the system is not working correctly, address it immediately. Be mindful not to allow the staff to establish bad habits; nip them in the bud while the new system is being implemented. Continuously check the reliability and validity of the system. If the data don’t look as expected, find out why. Reach out to other EDs with similar systems; contact the ENA for guidance.

6. Celebrate success! Be sure to celebrate the successful implementation of a reliable, valid five-level triage system. In 2004, only 3% of hospital EDs used a five-level system.³ Each ED with a successful implementation moves the United States closer to a standardized five-level triage system.