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Year : 2021  |  Volume : 19  |  Issue : 4  |  Page : 292-299

A review of triage practices and evolution of Christian Medical College, Vellore triage system (CMCTS) during the COVID-19 pandemic

1 Department of Emergency Medicine, Christian Medical College, Vellore, Tamil Nadu, India
2 Department of Emergency Nursing, Christian Medical College, Vellore, Tamil Nadu, India

Date of Submission16-Sep-2021
Date of Decision15-Oct-2021
Date of Acceptance27-Oct-2021
Date of Web Publication07-Dec-2021

Correspondence Address:
Dr. Kundavaram Paul Prabhakar Abhilash
Department of Emergency Medicine, Christian Medical College, Vellore - 632 004, Tamil Nadu
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/cmi.cmi_77_21

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Triage is practiced in hospitals around the world and has proved its worth in identifying and prioritizing sick patients for emergency resuscitation, especially in resource-limited settings. Both formal and informal systems are utilized in different health centers to differentiate between patients with varying severity of illness. The Christian Medical College, Vellore Triage System (CMCTS) developed at our emergency department (ED) in 1997 is a four-category system that makes this differentiation based on presenting symptoms, signs, and predefined physiological parameters. In our ED, triaging is performed by a triage team composed of both nursing personnel and emergency physicians. During the COVID-19 pandemic, our triaging system was modified to segregate potential COVID and non-COVID patients into different zones for containment and for safety of healthcare workers.

Keywords: COVID-19, emergency department, hospital triage systems, triage

How to cite this article:
George AS, Ganesan P, Christopher J, Paul S, Abhilash KP. A review of triage practices and evolution of Christian Medical College, Vellore triage system (CMCTS) during the COVID-19 pandemic. Curr Med Issues 2021;19:292-9

How to cite this URL:
George AS, Ganesan P, Christopher J, Paul S, Abhilash KP. A review of triage practices and evolution of Christian Medical College, Vellore triage system (CMCTS) during the COVID-19 pandemic. Curr Med Issues [serial online] 2021 [cited 2023 May 31];19:292-9. Available from: https://www.cmijournal.org/text.asp?2021/19/4/292/331841

  Introduction Top

The front doors of a hospital's emergency department (ED) are the refuge of many sickly patients seeking urgent care at any hour. As the wing of the hospital offering the most informal access, it is often a place of restless activity with anxious relatives and hospital staff bustling about purposefully. Without a system of triage that ensures severely sick patients are attended to immediately and that limited resources are appropriately allocated, it is easy to imagine how this scene could potentially devolve into one of pandemonium and despair.

Triage is the sieve through which patients are sorted into different categories of urgency based on the precariousness of their health status. Such a “;prioritization” of patients has been practiced for the past 200 years and has found application in settings of varying social stability and resource-to-patient availability.[1] These settings include battlefields, hospitals, and sites of mass casualty events.

Triage has undergone constant development since its emergence, and over the past few decades, multiple systems of triage have been designed that best cater to the health center that employs it. In this article, which primarily focuses on ED triage, we describe the Christian Medical College, Vellore Triage System (CMCTS) devised in our institute. Our hospital is a 2500-bedded tertiary care referral center in Tamil Nadu, South India, with an ED that receives approximately 75,000 patients a year. We have touched upon the origins of triage and its evolution over the years and provided a brief overview of various systems of triage currently employed worldwide. We also review the modified CMCTS, which was used during the COVID-19 pandemic, devised for infection control and to protect patients and healthcare workers.

  History of Triage Top

The etymology of triage is commonly traced back to the French word “;trier” meaning “;to sort.” It was first implemented in times of warfare after the advent of military surgeons around the beginning of the 18th century.[2] Preceding this, soldiers were treated on a “;first come, first served” basis, irrespective of the graveness of injury, patient salvageability, or effective use of resources. It was not unusual for officers to be attended to first while foot soldiers were left to die on the battlefield.

The first formal battlefield use of triage is commonly attributed to two French military surgeons in the Napoleonic Wars (1803–1815): Pierre-François Percy and Dominique-Jean Larrey.[3] While Percy prioritized soldiers who could be treated quickly and returned to combat, Larrey propounded that care should first be afforded to those with critical injuries and that the less severely wounded could be made to wait. Larrey is also credited for his construction of the “;flying ambulance” that allowed rapid mobilization of the wounded from the battlefield. Over the next two centuries, both wartime weaponry and medical treatment saw numerous advances.[4] Triaging was refined over these years to reflect the availability of improved transport facilities and medical resources.

  Hospital Triage Systems Top

While triaging in war often prioritized soldiers who could be “;patched up” and returned to the battlefield, hospital triaging was intent on delivering immediate care to the most severely ill or wounded first. The earliest systematic description of the use of triage in civilian hospital EDs, as described by Weinerman et al. in Baltimore, USA, dates as late as 1966.[5] Triage officers would classify patients based on their assessment of the time-sensitivity of patients' condition, a system that lacked objectivity and organization. Since then, triaging has improved, with physiological parameters, algorithms, and red flags, among other tools, being laid down to facilitate the process while optimizing interrater reliability and reproducibility.

The rise of emergency medicine as a distinct specialty gained momentum in the 1960s. This was mostly in response to greater numbers of patients inundating the “;casualty,” causing a demand–supply mismatch, resulting in poor accommodation of patients and an unacceptable level of care for both accident and medical emergencies.[6] It became clear that the acutely ill and injured needed to be differentiated from those with minor illness and given immediate attention, by specialists if required. As the practice of emergency medicine grew and improved, it catalyzed the development of more formalized systems of triage that both facilitated ED performance evaluation and also catered to the patient load and resource availability of the respective health center. Patients were triaged across a number of categories, ranging from 2 to 10, with the use of 3–5 triage categories gaining increased popularity.[1] The 1990s witnessed initiatives in a few countries toward the construction of nationalized triage scales.[7] A few of these systems which have gained international recognition are described below and summarized in [Figure 1].
Figure 1: Timeline illustrating the development of popular triage systems and triage in India.

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Australasian Triage System

In Australia, the earliest documented triage system was the three-category system devised at Box Hill Hospital, Victoria, in the 1980s, which was later updated to a five-category system.[8] The system at Box Hill gained traction in the medical community, and over the following years, it was adjusted and refined to eventually inspire the formation of the National Triage Scale (NTS) in 1994, which would become the Australasian Triage Scale (ATS) in 2000.[9] In this system, triaging is done based on presenting complaints and the use of “;modifiers” including vital parameters and red flag symptoms, which guide the triage nurse on making a final decision.

Canadian Triage and Acuity Scale

In a bid to standardize ED practices in Canada and to allow for better benchmarking of ED performance, the Canadian Association of Emergency Physicians (CAEP) developed a five-category scale in 1994, which was based on the fundamentals of the NTS.[10] This later led to the establishment of the Canadian Triage and Acuity Scale (CTAS), which was endorsed by the CAEP and the National Emergency Nurses Affiliation in 1998, with its first guidelines on implementation being published in 1999.[11]

Manchester Triage Scale

The Manchester Triage Scale is another well-recognized and validated five-category scale developed in 1996 and employed in EDs in the United Kingdom.[12] It involves a series of 52 presentational flowcharts for various clinical scenarios, which can be referred once the patient's presenting complaint is identified. The charts highlight certain “;determinants” for each scenario (similar to modifiers in the ATS and CTAS), and the presence or absence of these influences the triage category assigned to the patient.

Emergency Severity Index

In the United States, three-level and four-level triaging were popular till the late 1990s. Poor reproducibility and ED overcrowding prompted the development of a five-category system called the Emergency Severity Index (ESI) in 1999 based on the resource requirement of the patient's condition, with greater resource demand being prioritized higher.[13] Here, a resource is defined as any investigational or interventional tool (radiography, blood tests, hydration, simple and complex procedures), beyond the physician history and clinical examination (simple dressings, oral medications, etc.), which would be required for the physician to reach a disposition decision.

Since their inception, these scales have been reviewed and revised periodically. A meta-analysis that compared their efficacy concluded that while these systems showed moderate-to-good validity in identifying high- and low-urgency patients, no one system could be deemed superior to another due to significant variability in their performance across different centers. Triage scales used in other countries, such as Taiwan and Japan, have been based on them. The salient features of the above-mentioned systems and a few other recognized ones are summarized in [Table 1].
Table 1: An overview of various triage systems

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Emergency medicine and triage in India

The establishment of the ED in India occurred at the turn of the 21st century.[14] Before the early 1990s, hospitals would receive unscheduled patients in a casualty manned by junior doctors with no postgraduate qualification and often temporarily employed. In 1994, one of the first EDs in India was established in Christian Medical College (CMC) in Vellore by a group of committed individuals who recognized the need for a formalized system of management of such patients.[14] A three-category triage system, known as the Christian Medical College, Vellore Triage System (CMCTS), was instituted in 1997 and was the first of its kind in India.[14] Over the next two decades, many institutions and hospitals designed their own triage systems or adapted established triage systems like ours. A recent article by Sahu et al. reported the functioning of a three-category All India Institute of Medical Sciences Triage Protocol (ATP) that was established in 2010, more than a decade after the inception of CMCTS.[15]

The CMCTS protocols have been revised and updated periodically and changed to a four-category triage system in 2012. With the advent of the COVID-19 pandemic, the CMCTS was further modified to cater to the needs of isolation and segregation of COVID-19-suspect patients. Our triage system segregates trauma and nontrauma patients based on presenting complaints, warning signs, and physiological parameters, with a target time to treatment designated for each priority. A four-tier system was adopted, instead of a five-tier system, as it offered quicker evaluation and treatment of moderately ill patients who get prioritized to higher levels.

Triage methodology in Christian Medical College, Vellore

Patients presenting to the ED of CMC, Vellore, are initially received in the triage area where they undergo their first assessment. This area is composed of three triage desks manned by two nursing staff and one ED physician, who comprise the triage team. Patient details, including presenting complaints, vital signs, and medicolegal documentation, and the final triaging decision are entered into an in-house online database, termed the ED module, designed by the IT team at CMC, Vellore. Such a practice facilitates both record-keeping and research endeavors by aiding in data collection and analysis. Other resources available at the triage area are a point-of-care kit, a “;medication box,” an electrocardiogram (ECG) room, and first-aid for splinting and hemorrhage control in trauma.

On receiving the patient, the triage nurse conducts the following triaging process:

  1. Brief primary assessment of the patient including evaluation of airway, breathing, circulation, disability
  2. Focused history of the patient's condition illustrating the reason for the ED visit
  3. Measurement of physiologic parameters including pulse, blood pressure, respiratory rate, and pulse oximetry; perform bedside tests which aid in immediate management of the patient including serum and urine ketones and ECG
  4. Screening for infectious diseases such as tuberculosis and COVID-19 through history and perusal of medical documentation and appropriate segregation and isolation of patients in designated areas
  5. Assigning a triage priority to the patient; securing color-coded wrist bands that denote the priority level and contain patient details
  6. Providing pain relief by issuing oral analgesics, if appropriate, after consultation with the triage physician, administration of first-aid for trauma patients, e.g., dressing, splints.

Based on the triage team's assessment, patients are stratified into one of the following four categories:

  • CMCTS Priority 1, Red zone

    • Time to evaluation/intervention: Immediate
    • Patients whose clinical status necessitates immediate life-saving interventions, which often include resuscitation and advanced life support. Patients in this category have severely compromised vital signs and require aggressive management. The “;Resuscitation Room” functions with immediate treatment and quick disposition times, and stabilized patients are usually admitted into intensive care wards or downtriaged to ensure room to receive the next critically ill patient. Examples of patients triaged into this category are described in [Table 1]

  • CMCTS Priority 2, Yellow zone

    • Time to evaluation: 10–120 min
    • Patients with complaints perceived as urgent, and with the possibility of deterioration, but with no immediate threat to life. These may include acute-onset illnesses or acute exacerbations of chronic conditions that require timely investigation and medical and/or procedural interventions. This priority includes two “;bays” for separate assessment of trauma and nontrauma patients. Details of triaging criteria for Priority 2 are described in [Table 2]
    Table 2: CMC Triage System Priority 1 (Red zone) protocol with examples

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  • CMCTS Priority 3, Green zone

    • Time to evaluation: 30 min to 4 h
    • Noncritical patients presenting with acute “;minor emergencies” and stable vital signs in ambulant patients who would benefit from the same-day investigation of their condition and symptomatic care such as pain medication and antiemetics or adjustments of their chronic medication. The upper limit on the time to treatment is 240 min (4 h)

  • CMCTS Priority 4

    • Time to evaluation: 30 min to 4 h
    • Patients with chronic medical conditions, such as chronic musculoskeletal pain or chronic heart or kidney disease, and no exacerbation in the severity of their symptoms. This often includes patients who lack a follow-up appointment and seek evaluation or referral to the concerned department from the ED, though this practice is suboptimal as it contributes to overcrowding and increased waiting times for potentially sicker patients. They are evaluated by an ED physician who might prescribe medications and order tests, the reports of which can be followed up in the respective outpatient clinics. Details of triage protocols for CMCTS Priorities 3 and 4 are described in [Table 3].
Table 3: CMC Triage System Priority 2 (Yellow zone) protocol with examples

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Following initial segregation by the triage nurse, patients are sometimes reprioritized by the physician in the respective zone, depending on illness progression and bed availability. Thus, triage remains a sustained activity in patient evaluation in the ED.

  Pain Assessment in Triage Top

The assessment and addressal of a patient's pain are requisites in the triage process. Pain quantification is done using the Universal Pain Assessment Tool or with visual aids using Wong–Baker faces.[16] The grading is as follows:

  1. Mild: Pain score 1–3
  2. Moderate: Pain score 4–7
  3. Severe: Pain score 8–10.

Patients in moderate and severe pain requiring parenteral analgesics are categorized as Priority 2, barring any indications for management in Priority 1. Priority 3 patients with mild-to-moderate pain receive oral analgesics at the triage desk, which is given by the nurse after consultation with the triage physician.

  Walk-In Triaging and Fast-Tracking Top

In the event of overcrowding in the ED, there is the concerning possibility of critically ill patients being inadvertently delayed at the triage line. In such situations, the practice of “;walk-in triaging” and “;fast-tracking” helps alleviate the hazards of a long waiting time to triage.

Walk-in triaging is carried out by the ED consultants or senior nursing staff and involves combing through patients waiting to be triaged to try and identify higher priority patients and triage them first. It is also used to recognize Priority 4 patients who can be directed to the outpatient clinics by taking a brief history and a quick check of the vital signs if a chronic history of complaints is determined.

Fast-tracking is conducted among Priority 3 patients who would greatly benefit from a reduced waiting time. This may include patients who could require quicker investigation, for example, those with atypical chest pain or stable trauma patients, or those who require immediate symptomatic relief, for example, a patient with recurrent episodes of vomiting. Once these patients are identified by the triage practitioner, they are directed to the waiting area, and their chart is placed on the top of the “;pile” by the triage nurse while the Priority 3 physician is notified that a patient has been fast-tracked and is awaiting evaluation.

  The Triage Physician Top

The role of the emergency physician in triage is versatile and extends beyond the triage desk. The duties of the physician include, but are not limited to:

  • Providing immediate assessment of patients when requested by the triage nurse who would aid the decision-making process, e.g., reviewing ECG of patients presenting with atypical chest pain
  • Ensuring a smooth inflow of patients with their proper placement. This necessitates an awareness of the occupancy status of the ED and investigating, and attempting to prevent, congestion at any particular area
  • Initiating life-saving measures at triage if required, including cardiopulmonary resuscitation and ventilatory support.

  Triage during the COVID-19 Pandemic Top

Since early 2020, healthcare around the world has been embroiled in the herculean task of dealing with the COVID-19 pandemic, which initially erupted from a cluster of cases in Wuhan, China. The shadow of the now infamous SARS-CoV-2 virus has rapidly spread across the face of the globe greedily claiming lives and causing untold suffering in its wake. Hospitals internationally are thronged with patients of all ages presenting along a spectrum of clinical exigencies ranging from minor flu-like symptoms to severe breathlessness requiring immediate resuscitation and ICU level care.

To limit nosocomial transmission and to protect our healthcare workers, CMC's ED was partitioned into two areas, each with separate entries and areas for triage:

  1. COVID-suspect zone – To treat suspect and positive COVID-19 cases
  2. Non-COVID zone – Where nonsuspects are managed.

Healthcare personnel working within the COVID-suspect zone were required to wear full personal protective equipment (PPE), which included N95 face masks, face shields, and disposable gowns and gloves.

In the early days of the pandemic, an epidemiological approach toward the segregation of COVID-suspect patients was adopted in our ED. Contact tracing of the initial cases and surveillance of the spread of COVID-19 in India identified states with high case burden and certain regions within which rapid spread was noted were labeled as “;COVID hotspots.” Patients with a history of international travel in the preceding 14 days, or those arriving from COVID-19 hotspots from within the country, were evaluated with a high index of suspicion for COVID-19 and were managed within an isolation area regardless of symptomatology.

The acknowledgment of community transmission of the virus in October 2020 rendered the separation of patients based on where they came from, or their travel and contact history, an inviable option.[17] Every patient would have to be evaluated individually and assessed for symptoms of COVID-19 illness; thus, the triage methodology metamorphosed from an epidemiological to an entirely symptomatic approach. Before triage, patients presenting to the ED were questioned by hospital staff wearing PPEs for features suggestive of an influenza-like illness (including symptoms such as fever, cough, and breathlessness) and, if present, were directed to be further triaged in the COVID-suspect zone. The guidelines for categorization of COVID-suspect patients are outlined in [Table 4].
Table 4: CMC Triage System: Priority 3 & 4 (Green zone) protocol with examples

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Table 5: CMC Triage system protocol for isolation of COVID.19 suspect patients during the pandemic

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The measures employed in our hospital to minimize exposure of patients, relatives, and healthcare workers by dividing the ED into separate zones helped contain the spread of infection and provided some degree of protection to those in the non-COVID zones. Amid these capricious times, our protocols and infrastructure were constantly updated and adjusted in light of fresh evidence or as unforeseen logistical difficulties were unearthed, a process that demanded much patience and flexibility from both patients and hospital staff alike.

The CMCTS was devised bearing in mind the limitations and challenges faced by the standard Indian healthcare center, including substantial patient inflow, limited resource availability, and financial constraints of the average Indian patient. Although the CMCTS is yet to be validated, we encourage its use in other Indian EDs if its implementation is deemed feasible.

  Conclusion Top

A four-category system of triage has been practiced in CMC, Vellore, for about two decades and over the course of time has proved its indispensability. A joint assessment of the patient at triage conducted by the triage team comprising an ED nurse and a physician aid in segregation of infectious illnesses, early identification of potentially unstable patients, and early interventions when needed. Our system has evolved over the years in accordance with improvements in medical care and to meet unprecedented challenges encountered by the healthcare system and the population it serves.

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Conflicts of interest

There are no conflicts of interest.

  References Top

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Iserson KV, Moskop JC. Triage in medicine, Part I: Concept, history, and types. Ann Emerg Med 2007;49:275-81.  Back to cited text no. 2
Nakao H, Ukai I, Kotani J. A review of the history of the origin of triage from a disaster medicine perspective. Acute Med Surg 2017;4:379-84.  Back to cited text no. 3
Mitchell GW. A brief history of triage. Disaster Med Public Health Prep 2008;2 Suppl 1:S4-7.  Back to cited text no. 4
Weinerman ER, Ratner RS, Robbins A, Lavenhar MA. Yale studies in ambulatory medical care. V. Determinants of use of hospital emergency services. Am J Public Health Nations Health 1966;56:1037-56.  Back to cited text no. 5
Sakr M, Wardrope J. Casualty, accident and emergency, or emergency medicine, the evolution. J Accid Emerg Med 2000;17:314-9.  Back to cited text no. 6
FitzGerald G, Jelinek GA, Scott D, Gerdtz MF. Emergency department triage revisited. Emerg Med J 2010;27:86-92.  Back to cited text no. 7
Ebrahimi M, Heydari A, Mazlom R, Mirhaghi A. The reliability of the Australasian Triage Scale: A meta-analysis. World J Emerg Med 2015;6:94-9.  Back to cited text no. 8
Forero DR. Australasian College for Emergency Medicine (ACEM) Literature Review on the Australasian Triage Scale (ATS). Sydney: University of New South Wales, 2012. p. 53.  Back to cited text no. 9
Beveridge R, Ducharme J, Janes L, Beaulieu S, Walter S. Reliability of the Canadian Emergency Department Triage and Acuity Scale: Interrater agreement. Ann Emerg Med 1999;34:155-9.  Back to cited text no. 10
Beveridge R. CAEP issues. The Canadian Triage and Acuity Scale: A new and critical element in health care reform. Canadian Association of Emergency Physicians. J Emerg Med 1998;16:507-11.  Back to cited text no. 11
Zachariasse JM, Seiger N, Rood PP, Alves CF, Freitas P, Smit FJ, et al. Validity of the manchester triage system in emergency care: A prospective observational study. PLoS One 2017;12:e0170811.  Back to cited text no. 12
Emergency Severity Index (ESI): A Triage Tool for Emergency Department. Available from: http://www.ahrq.gov/patient-safety/settings/emergency-dept/esi.html. [Last accessed on 2021 Sep 04].  Back to cited text no. 13
CMC Vellore. Available from: https://www.cmch-vellore.edu/DeptContent.aspx?dept=155. [Last accessed on 2021 Sep 05].  Back to cited text no. 14
Sahu AK, Bhoi S, Galwankar S, Aggarwal P, Murmu L, Nayer J, et al. All India Institute of Medical Sciences Triage Protocol (ATP): ATP of a busy emergency department. J Emerg Trauma Shock 2020;13:107-9.  Back to cited text no. 15
  [Full text]  
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  [Figure 1]

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]


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