With over 12.3 million cases and 550,000 deaths worldwide at the time of this writing, the global impact of COVID-19 is ever increasing. 1, 2 Widespread community transmission is occurring in the United States (US) and health systems around the world continue to face challenges in the management of COVID-19 patients. 3 Hospitals across the United States have adapted to the COVID-19 pandemic by limiting nonessential patient interaction and transforming their emergency departments (EDs) to treat patients who are both critically ill and highly contagious. 4 With the looming threat of recurrent patient surges ever on the horizon, emergency clinicians must thoughtfully consider how to best Supervising Editor: Angela Lumba-Brown, MD. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. © 2020 The Authors. JACEP Open published by Wiley Periodicals LLC on behalf of the American College of Emergency Physicians.
handle an influx of patients while limiting the exposure of themselves and others. 4 This article offers triage tools that the authors believe will help us provide better care for our patients, protect our colleagues and patients alike, and contribute to the greater public health response to the pandemic.
US healthcare systems are structured such that emergency clinicians stand on the frontline of any pandemic. Although other departments can regulate patient flow and volume with scheduled encounters or operating room allocation, EDs must respond efficiently and effectively to any patient surge. Worldwide data indicates that ∼25% of JACEP Open 2020;1-6.
wileyonlinelibrary.com/journal/emp2 COVID-19 patients require critical care resources. 5 a number of protocolized approaches borne out of this need. 13 The majority of prediction rules designed for allocation of critical care resources during a pandemic were developed in response to influenza outbreaks during the 20th century. These rules rely largely on laboratory and radiologic findings performed after the initial evaluation to categorize patients, and are therefore less helpful in the immediate triage setting. 15, 16 Of more acute relevance, the Centers for Disease Control and Prevention (CDC) created a "Pandemic Influenza Triage Algorithm" (PITA) in response to the 2009 H1N1 pandemic. PITA incorporates triage data to categorize patients into 5 levels ranging from those requiring immediate resuscitation (red, level 1), to those requiring only a cursory evaluation before discharge (green, level 5). The PITA algorithm was designed to triage patients rapidly and effectively upon initial evaluation, rationally minimize PPE usage, and limit nosocomial transmission.
Its core tenets are readily translatable to the COVID-19 outbreak. 17 
The authors adapted the PITA algorithm into a specialized COVID-19
triage algorithm (see Figure 1 ) with the same primary goals of assigning arise.
In our system, the algorithm was designed and implemented at the A lack of required testing prior to level of care designation is felt to be a major strength of the algorithm as it expedites the triage process. The algorithm was designed prior to the widespread availability of rapid COVID-19 testing, and as such, it was intentionally not mandated in the algorithm. Additionally, on initial presentation and subsequent triage, COVID-19 testing results are not routinely available for rapid decisionmaking in the ED setting. All testing should be adapted to local and institutional guidelines.
"Need Resuscitation-Red" patients are defined in our algorithm as patients in full arrest or extremis, patients with an inability to protect their airway, patients with frank respiratory failure or apnea, patients with significant hypoxemia (<88% at sea level), patients in shock, or patients with significant alteration in mental status. These patients are universally assumed to be PUIs. We recommend use of the highest level of PPE for these patients (as indicated in Figure 1 ), because they may need to undergo high risk aerosolizing-generating procedures (ie, endotracheal intubation, non-invasive ventilation). [25] [26] [27] [28] The authors additionally recommend use of an airborne infection isolation room (AIIR, or "negative pressure room") for patients under-going aerosolizing-generating procedures given the significant risk for airborne disease transmission during such procedures. [25] [26] [27] [28] The patient can be transferred or dispositioned to a non-AIIR if appropriate filtration devices are used. These patients should be admitted to an intensive care setting. Further, we recommend considering a chest
x-ray prior to, or immediately following, admission along with testing for COVID-19 as available and other testing as indicated.
Patients not in extremis must have "1 or more symptoms consistent with COVID-19" identifying them as a PUI. We initially defined these criteria as fever, cough (dry or productive), or shortness of 
In addition to providing a framework for clinical triage, our algorithm describes the recommended levels of personal protective equipment (PPE) for each type of expected encounter. Significant rates of infection among health care workers and nosocomial infection illustrate the need for adequate clinician protection and infection control. 21, 27 SARS-CoV-2 seems to have a viral shedding pattern similar to influenza. 34, 35 High viral loads have been detected in completely asymptomatic patients, calling for a minimum level of protection from respiratory droplets for all clinicians. 30,36 SARS-CoV-2 was also noted in stool in 50% of patients tested, and extensive surface contamination has been reported. 37, 38 The potential for stool or fluid transmission suggest the need for concomitant contact precautions for providers within reach of a patient or contaminated surface. 30, 34 The most significant controversy involving SARS-CoV-2 transmission seems to be the potential for routine airborne or aerosol spread. It is thought that the highest risk for airborne transmission occurs during aerosolizing-generating procedures, but the virus has been found to be viable in aerosols for at least 3 h. 24 
Droplet: distance >6 feet (greens, some yellows)
We recommend clinicians approaching all green and yellow patients wear, at minimum, a procedural mask and gloves if remaining at least 6 feet from the patient (a widely accepted range for typical droplet transmission). We recommend clinicians evaluating patients at a distance <6 feet follow the Contact + Droplet precautions below. All PUIs should be given a procedural mask on entry. Clinician exposure to low acuity patients should be rapid and at the safest feasible distance to obtain an accurate assessment of the patient with the minimum amount of PPE necessary to adequately and safely care for a patient.
Contact + droplet: distance <6 feet (some yellows, blues, pinks, some reds)
Many well-appearing patients may require more extensive evaluation, typified by those with relevant risk factors and abnormal vital signs as above. 30 For those patients requiring the clinician to approach within 6 feet to auscultate, examine, or intervene, we recommend at minimum a procedural mask, face shield or goggles, isolation gown, and gloves, consistent with WHO, CDC, and Canadian guidelines. 26, 29, 39 This level of PPE provides respiratory droplet and contact protection.
Patients presenting in extremis or requiring immediate resuscitation will likely require aggressive respiratory support or invasive proce- Our algorithm also assumes that a facility will have nursing providers available for use in triage as well as a physician or advanced practice providers readily available for further stratification of patients. We recognize that many EDs will not have equivalent capabilities and some aspects of the algorithm may have to be adapted to local circumstances.
We support the use of an experienced nursing provider in place of a physician or APP in the triage setting if necessary.
Our algorithm was designed with thoughtful resource allocation in mind and aims to provide adequate protection for the most providers in the setting of limited resources and PPE, an unfortunate and continued reality of the COVID-19 pandemic. Recent data lends more support to the possibility of airborne transmission of the virus even in the absence of aerosolizing-generating procedures. 35 In light of this, the authors again recommend the use of constant airborne and contact precautions by all providers experiencing close contact as with PUIs as resource allocation allows.
As the COVID-19 pandemic continues to evolve, so too will our understanding of the best patient care and management strategies. Dynamic changes in WHO and CDC guidelines have already occurred with incorporation of evidence-based clinical features, and it is vital to continually update our approach to any pathogen as new information is obtained.
The proposed triage algorithm was designed to facilitate the timely evaluation of PUIs in an organized fashion that optimizes patient triage, minimizes unnecessary clinician exposure, standardizes care, and maximizes appropriate resource use in the setting of an ongoing PPE shortage. These measures will continue to be essential in the coming months.
It is the authors' hope that use of this triage algorithm and PPE recommendations will aid frontline emergency clinicians in the ongoing response to COVID-19.
Douglas W. Wallace MD https://orcid.org/0000-0002-7714-8156