Triage is a process of prioritizing patients based on the severity of their condition so as to treat as many as possible when resources are insufficient for all to be treated immediately. The term comes from the French verb trier, meaning to separate, sort, sift or select. There are two types of triage: simple triage and advanced triage.
Types of triage
Simple triage is usually used in a scene of mass casualty
, in order to sort patients into those who need critical attention and immediate transport to the hospital and those with less serious injuries. This step can be started before transportation becomes available. The categorization of patients based on the severity of their injuries can be aided with the use of printed triage tags
or colored flagging
S.T.A.R.T. (Simple Triage and Rapid Treatment) is a simple triage system that can be performed by lightly-trained lay and emergency personnel in emergencies. It is not intended to supersede or instruct medical personnel or techniques. It may serve as an instructive example, and has been (2003) taught to California emergency workers for use in earthquakes. It was developed at Hoag Hospital in Newport Beach, California for use by emergency services. It has been field-proven in mass casualty incidents such as train wrecks and bus accidents, though it was developed for use by CERTs and firemen after earthquakes.
Triage separates the injured into four groups:
- The deceased who are beyond help
- The injured who can be helped by immediate transportation
- The injured whose transport can be delayed
- Those with minor injuries, who need help less urgently
However, these descriptive words are by no means standard; different regions use different designations.
In the UK and Europe, the triage process used is similar to that of the United States, but the categories are different:
- Dead - those who are pronounced as such by a medically qualified person or paramedic who is legally qualified to pronounce death
- Immediate - patients who have a trauma score of 3 to 10 (RTS) and need immediate attention
- Urgent - patients who have a trauma score of 10 or 11 and can wait for a short time before transport to definitive medical attention
- Delayed - patients who have a trauma score of 12 (maximum score) and can be delayed before transport from the scene
A simplified but effective description of the S.T.A.R.T. is taught in the Israeli army to non-medical personnel: the injured who are lying on the ground silently should be prepared for immediate transportation; injured lying on the ground but screaming are injured whose transportation can be delayed; and the walking wounded need help less urgently. Non-medical personnel have no authority to tag an injured person as deceased.
Simple triage identifies which people need advanced medical care.
In the field, triage also sets priorities for evacuation
In S.T.A.R.T., casualties should be evacuated as follows:
- Deceased are left where they fell, covered if necessary; note that in S.T.A.R.T. a person is not triaged "deceased" unless they are not breathing and an effort to reposition their airway has been unsuccessful.
- Immediate or Priority 1 (red) evacuation by MEDEVAC if available or ambulance as they need advanced medical care at once or within 1 hour. These people are in critical condition and would die without immediate assistance.
- Delayed or Priority 2 (yellow) can have their medical evacuation delayed until all immediate persons have been transported. These people are in stable condition but require medical assistance.
- Minor or Priority 3 (green) are not evacuated until all immediate and delayed persons have been evacuated. These will not need advanced medical care for at least several hours. Continue to re-triage in case their condition worsens. These people are able to walk, and may only require bandages and antiseptic.
In advanced triage, doctors may decide that some seriously injured people should not receive advanced care because they are unlikely to survive. Advanced care will be used on patients with less severe injuries. Because treatment is intentionally withheld from patients with certain injuries, advanced triage has ethical implications. It is used to divert scarce resources away from patients with little chance of survival in order to increase the chances of survival of others who are more likely to survive.
In Western Europe, the criterion used for this category of patient is a trauma score of consistently at or below 3. This can be determined by using the Triage Revised Trauma Score (TRTS), a medically validated scoring system incorporated in some triage cards.
The use of advanced triage may become necessary when medical professionals decide that the medical resources available are not sufficient to treat all the people who need help. The treatment being prioritized can include the time spent on medical care, or drugs or other limited resources. This has happened in disasters such as volcanic eruptions, thunderstorms, and rail accidents. In these cases some percentage of patients will die regardless of medical care because of the severity of their injuries. Others would live if given immediate medical care, but would die without it.
In these extreme situations, any medical care given to people who will die anyway can be considered to be care withdrawn from others who might have survived (or perhaps suffered less severe disability from their injuries) had they been treated instead. It becomes the task of the disaster medical authorities to set aside some victims as hopeless, to avoid trying to save one life at the expense of several others.
If immediate treatment is successful, the patient may improve (although this may be temporary) and this improvement may allow the patient to be categorized to a lower priority in the short term. Triage should be a continuous process and categories should be checked regularly to ensure that the priority remains correct. A trauma score is invariably taken when the victim first comes into hospital and subsequent trauma scores taken to see any changes in the victim's physiological parameters. If a record is provided back in time, the receiving hospital doctor can see a historical trauma score going back in time to the incident. This should allow more definitive treatment to be carried out earlier than might otherwise be the case.
Categories of severity
In advanced triage systems, secondary triage is typically implemented by paramedics
, battlefield medical personnel
or by skilled nurses
in the emergency departments of hospitals during disasters, injured people are sorted into five categories. Black / Expectant: They are so severely injured that they will die of their injuries, possibly in hours or days (large-body burns, severe trauma, lethal radiation dose), or in life-threatening medical crisis that they are unlikely to survive given the care available (cardiac arrest
, septic shock
, severe head or chest wounds); they should be taken to a holding area and given painkillers
as required to reduce suffering.Red / Immediate: They require immediate surgery or other life-saving intervention, and have first priority for surgical teams or transport to advanced facilities; they "cannot wait" but are likely to survive with immediate treatment.Yellow / Observation: Their condition is stable for the moment but requires watching by trained persons and frequent re-triage, will need hospital care (and would receive immediate priority care under "normal" circumstances).Green / Wait (walking wounded): They will require a doctor's care in several hours or days but not immediately, may wait for a number of hours or be told to go home and come back the next day (broken bones without compound fractures, many soft tissue injuries).White / Dismiss (walking wounded):They have minor injuries; first aid and home care are sufficient, a doctor's care is not required. Injuries are along the lines of cuts and scrapes, or minor burns.
Note that this scale is more complex than simple triage.
Medical professionals should refer to professional texts and training references when implementing advanced triage; this listing is only for a layman's understanding.
Some crippling injuries, even if not life-threatening, may be elevated in priority based on the available capabilities.
During peacetime, most amputations may be triaged "Red" because surgical reattachment must take place within minutes, even though in all probability the person will not die without a thumb or hand.
In addition to the standard practices of triage as mentioned above, there are conditions where sometimes the less wounded are treated in preference to the more severely wounded. This may arise in a situation such as war where the military setting may require soldiers be returned to combat as quickly as possible, or disaster situations where medical resources are limited in order to conserve resources for those likely to survive but requiring advanced medical care. Other possible scenarios where this could arise include situations where significant numbers of medical personnel are among the affected patients where it may be advantageous to ensure that they survive to continue providing care in the coming days especially if medical resources are already stretched. In cold water drowning incidents, it is common to use reverse triage because drowning victims in cold water can survive longer than in warm water if given immediate BLS
and often those who are rescued and able to breathe on their own will improve with minimal or no help.
Continuous integrated triage
Continuous Integrated Triage
is an approach to triage in mass casualty
situations which is both efficient and sensitive to psychosocial and disaster behavioral health
issues that effect the number of patients seeking care (surge), the manner in which a hospital or healthcare facility deals with that surge (surge capacity
) and the overarching medical needs of the event.
Continuous Integrated Triage combines three forms of triage with progressive specificity to most rapidly identify those patients in greatest need of care while balancing the needs of the individual patients against the available resources and the needs of other patients. Continuous Integrated Triage employs:
However any Group, Individual and/or Hospital Triage system can be used at the appropriate level of evaluation.
Triage in France
, the triage in case of a disaster uses a four-level scale:
- DCD: décédé (deceased), or urgence dépassée (beyond urgency)
- UA: urgence absolue (absolute urgency)
- UR: urgence relative (relative urgency)
- UMP: urgence médico-psychologique (medical-psychological urgency) or impliqué (implied, i.e. lightly wounded or just psychologically shocked).
This triage is performed by a physician called médecin trieur (sorting medic). This triage is usually performed at the field hospital (PMA–poste médical avancé, i.e. forward medical post). The absolute urgencies are usually treated onsite (the PMA has an operating room) or evacuated to a hospital. The relative urgencies are just placed under watch, waiting for an evacuation. The involved are addressed to another structure called the CUMP–Cellule d'urgence médico-psychologique (medical-psychological urgency cell); this is a resting zone, with food and possibly temporary lodging, and a psychologist to take care of the brief reactive psychosis and avoid post-traumatic stress disorder.
In the emergency room of a hospital, the triage is performed by a physician called MAO–médecin d'accueil et d'orientation (reception and orientation physician), and a nurse called IOA– infirmière d'organisation et d'accueil (organisation and reception nurse). Some hospitals and SAMU organisations now use the "Cruciform" card referred to elsewhere.
Triage in the UK
In the UK
, the commonly used triage system is the Smart Incident Command System
, taught on MIMMS (Major Incident Medical Management (and) Support). The UK Armed Forces
are also using this system on operations worldwide. This grades casualties from Priority 1 (most urgent) to Priority 4 (expectant, i.e. likely to die).
Another system is the Cruciform and Manchester triage.
Triage in Canada
In the mid-1980s
, The Victoria General Hospital
, in Halifax, Nova Scotia
, introduced paramedic triage in its Emergency Department. Unlike all other centres in North America
that employ physician and primarily nurse triage models, this hospital began the practice of employing Primary Care level paramedics to perform triage upon entry to the Emergency Department. In 1997
, following the amalgamation of two of the city's largest hospitals, the Emergency Department at the Victoria General closed. The paramedic triage system was moved to the city's only remaining adult emergency department, located at the New Halifax Infirmary. In 2006, a triage protocol on whom to exclude from treatment during a flu pandemic was written by a team of critical-care doctors at the behest of the Ontario government. The protocol was published in the Canadian Medical Association Journal
For routine emergencies, many locales in Canada now employ the Canadian Triage and Acuity Scale for all incoming patients. The system categorizes patients by both injury and physiological findings, and ranks them by severity from 1-5. The model is used by both paramedics and E/R nurses, and also for pre-arrival notifications in some cases. The model provides a common frame of reference for both nurses and paramedics, although the two groups do not always agree on scoring (particularly when there is a shortage of available beds in the E/R) results. It also provides a method, in some communities, for benchmarking the accuracy of pre-triage of calls using AMPDS (What percentage of Delta calls have return priorities of CTAS 1,2,3, etc.)and these findings are reported as part of a municipal performance benchmarking initiative in Ontario. Curiously enough the model is not currently used for mass casualty triage, and is replaced by the START protocol and METTAG triage tags.
Triage in North Korea
During the food crisis of the early 1990s the People's republic of North Korea
adopted a system of triage to allocate aid and food in order to ensure their military and high ranking cadres were allotted ample rations. This often left the population in the urban north in particular to scrounge for food or die.
Hospital triage systems in the United States
For a typical inpatient hospital triage system, a triage physician will either field requests for admission from the ER physician on patients needing admission or from physicians taking care of patients from other floors who can be transferred because they no longer need that level of care (i.e. intensive care unit patient is stable for the medical floor). This helps keep patients moving through the hospital in an efficient and effective manner.
This triage position is often done by a hospitalist. A major factor contributing to the triage decision is available hospital bed space. The triage hospitalist must determine, in conjunction with a hospital's "bed control" and admitting team, what beds are available for optimal utilization of resources in order to provide safe care to all patients. A typical surgical team will have their own system of triage for trauma and general surgery patients. This is also true for neurology and neurosurgical services.
The overall goal of triage, in this system, is to both determine if a patient is appropriate for a given level of care and to ensure that hospital resources are utilized effectively.
EMS triage in Germany
The german triage system also uses 4, sometimes 5 colour codes to denote the urgency of treatment. Typically, every Ambulance is equipped with a folder or bag with coloured ribbons or triage tags.
The urgency is denoted as follows:
|| examples |
| T1 (I)
|| acute danger for life
|| immediate treatment, transport as soon as possible
|| arterial lesions, internal haemorrhage, major amputations |
| T2 (II)
|| severe injury
|| constant observation and rapid treatment, transport as soon as practical
|| minor amputations, flesh wounds, fractures and dislocations |
| T3 (III)
|| minor injury or no injury
|| treatment when practical, transport and/or discharge when possible
|| minor lacerations, sprains, abrasions |
| T4 (IV)
|| no or small chance of survival
|| observation and if possible administration of analgesics
|| severe injuries, uncompensated blood loss, negative neurological assessment |
| T5 (V)
|| collection and guarding of bodies, identification when possible
|| dead on arrival, downgraded from T1-4, no spontaneous breathing after clearing of airway |
Preliminary assessment of injuries is usually done by the first ambulance crew an scene, after his arrival, the first Emergency physician
an scene will take over.
As a rule, there will be no cardiopulmonary resuscitation, so patients who do not breathe on their own or develop circulation after their airways are cleared, will be tagged "deceased".
Also, not every major injury automatically qualifies for a red tag, a patient with a traumatic amputation of the forearm might just be tagged yellow, his bleeding stopped and he being sent to a hospital when it is possible.
After the preliminary assessment, a more specific and definite triage will follow, as soon as patients are brought to a field treatment facility. There, they will be disrobed and fully examined by an emergency physician. This will take approximately 90 seconds per patient.
Alternative care facilities
Alternative care facilities are places that are setup for the care of large numbers of patients, or are places that could be so set up. Examples include schools, sports stadiums, and large camps that can be prepared and used for the care, feeding, and holding of large numbers of victims of a mass casualty event.
History and origin
Triage originated and was first formalized in WWI by French doctors treating the battlefield wounded at the aid stations behind the front. Much is owed to the work of Dominique Jean Larrey
during the Napoleonic Wars
. Historically, there has been a broad range of attempts to triage patients, and differing approaches and patient tagging systems used in a variety of different countries. Triage has, in fact, existed for a very long time, without fancy names or pretty tags. Until recently, triage results, whether performed by a paramedic or anyone else, were frequently a matter of the 'best guess', as opposed to any real or meaningful assessment. In fact, triaging used to be taught with an emphasis on the speed of the function, rather than the accuracy of the outcome. At its most primitive, those responsible for the removal of the wounded from a battlefield or their care afterwards have always divided victims into three basic categories:
1) Those who are likely to live, regardless of what care they receive;
2) Those who are likely to die, regardless of what care they receive;
3) Those for whom immediate care might make a positive difference in outcome.
The truth is that for many EMS systems, a similar model can sometimes still be applied. Once a full response has occurred and many hands are available, virtually every paramedic will use the model included in their service policy and standing orders. In the earliest stages of an incident, however, when there are one or two paramedics and twenty or more patients, sheer practicality demands that the above model will be used. As in virtually all aspects of EMS, there are times when 'back to basics' is the only approach that will be effective.
Modern approaches to triage are more scientific. The outcome and grading of the victim is frequently the result of physiological and assessment findings. Some models, such as the START model, are committed to memory, and may even be algorithm-based.
Undertriage and overtriage
Undertriage and overtriage are two key concepts that are imperative to understanding the triage process. Undertriage is the process of underestimating the severity of an illness or injury. An example of this would be categorizing a Priority 1 (Immediate) patient as a Priority 2 (Delayed) or Priority 3 (Minimal). Historically, acceptable undertriage rates have been deemed 5% or less. Overtriage is the process of overestimating the level to which an individual has experienced an illness or injury. An example of this would be categorizing a Priority 3 (Minimal) patient as a Priority 2 (Delayed) or Priority 1 (Immediate). Acceptable overtriage rates have been typically up to 50% in an effort to avoid Undertriage.
Burstein, J. L. & Hogan, D. E. (2007). Disaster Medicine (2nd ed.). Philadelphia, PA: Lippincott Williams & Wilkins.