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Triage of Scarce Critical Care Resources in COVID-19 An Implementation Guide for Regional Allocation

2020; Elsevier BV; Volume: 158; Issue: 1 Linguagem: Inglês

10.1016/j.chest.2020.03.063

1931-3543

Ryan C. Maves, James Downar, Jeffrey R. Dichter, John L. Hick, Asha V. Devereaux, James A. Geiling, Niranjan Kissoon, Nathaniel Hupert, Alexander S. Niven, Mary A. King, Lewis Rubinson, Dan Hanfling, James G. Hodge, Mary Faith Marshall, Katherine Fischkoff, Laura Evans, Mark R. Tonelli, Randy S. Wax, Gilbert Seda, Scott Parrish, Robert D. Truog, Charles L. Sprung, Christian Sandrock,

Trauma and Emergency Care Studies

Public health emergencies have the potential to place enormous strain on health systems. The current pandemic of the novel 2019 coronavirus disease has required hospitals in numerous countries to expand their surge capacity to meet the needs of patients with critical illness. When even surge capacity is exceeded, however, principles of critical care triage may be needed as a means to allocate scarce resources, such as mechanical ventilators or key medications. The goal of a triage system is to direct limited resources towards patients most likely to benefit from them. Implementing a triage system requires careful coordination between clinicians, health systems, local and regional governments, and the public, with a goal of transparency to maintain trust. We discuss the principles of tertiary triage and methods for implementing such a system, emphasizing that these systems should serve only as a last resort. Even under triage, we must uphold our obligation to care for all patients as best possible under difficult circumstances. Public health emergencies have the potential to place enormous strain on health systems. The current pandemic of the novel 2019 coronavirus disease has required hospitals in numerous countries to expand their surge capacity to meet the needs of patients with critical illness. When even surge capacity is exceeded, however, principles of critical care triage may be needed as a means to allocate scarce resources, such as mechanical ventilators or key medications. The goal of a triage system is to direct limited resources towards patients most likely to benefit from them. Implementing a triage system requires careful coordination between clinicians, health systems, local and regional governments, and the public, with a goal of transparency to maintain trust. We discuss the principles of tertiary triage and methods for implementing such a system, emphasizing that these systems should serve only as a last resort. Even under triage, we must uphold our obligation to care for all patients as best possible under difficult circumstances. The current pandemic of the novel 2019 coronavirus disease (COVID-19) because of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to a substantial increase in the demands on acute and critical care services in hospitals around the world. Even modest numbers of critically ill patients with COVID-19 are rapidly exceeding existing hospital capacity. Although a minor or moderate surge can be accommodated by using conventional and contingency surge strategies such as conserving, substituting, adapting, and reusing existing resources, current experiences from other countries managing COVID-19 suggest that the magnitude of the surge will substantially exceed capacity, necessitating a crisis surge response.1Einav S. Hick J.L. Hanfling D. et al.Surge capacity logistics: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146 (e17S-43S)Google Scholar, 2Hick J.L. Christian M.D. Sprung C.L. European Society of Intensive Care Medicine's Task Force for intensive care unit triage during an influenza epidemic or mass d. Chapter 2Surge capacity and infrastructure considerations for mass critical care. Recommendations and standard operating procedures for intensive care unit and hospital preparations for an influenza epidemic or mass disaster.Intensive Care Med. 2010; 36 (suppl 1): S11-S20Crossref PubMed Scopus (59) Google Scholar, 3Hick J.L. Einav S. Hanfling D. et al.Surge capacity principles: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146: e1S-e16SAbstract Full Text Full Text PDF PubMed Scopus (114) Google Scholar, 4Hick JL, Hanfling D, Wynia MK, Pavia AT. Duty to plan: health care, crisis standards of care, and novel coronavirus SARS-CoV-2. NAM Perspectives. Discussion paper. Washington, DC: National Academy of Medicine. https://doi.org/10.31478/202003b. Accessed June 10, 2020.Google Scholar The clinical demands will exceed the ability to provide one or more crucial resources essential to deliver basic critical care, therefore necessitating decisions regarding the reallocation of resources. This potential requires preparation of a triage system to best allocate available critical care resources to meet severe surge to maximize benefit for the greatest number of people.4Hick JL, Hanfling D, Wynia MK, Pavia AT. Duty to plan: health care, crisis standards of care, and novel coronavirus SARS-CoV-2. NAM Perspectives. Discussion paper. Washington, DC: National Academy of Medicine. https://doi.org/10.31478/202003b. Accessed June 10, 2020.Google Scholar,5Christian M.D. Sprung C.L. King M.A. et al.Triage: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146: e61S-e74SAbstract Full Text Full Text PDF PubMed Scopus (142) Google Scholar Importantly, this triage system should only be deployed as a last resort and implemented as resources become limited and after all attempts to surge, move patients, or shift resources from regions with greater availability have been made. When implemented, triage must be applied to all current and new patients presenting with critical illness, regardless of the diagnosis of COVID-19 or another illness, while maintaining underlying ethical principles of social justice, beneficence, nonmaleficence, respect for people and their dignity, veracity and the need to uphold trust within society, and fidelity to one another within health systems. We must uphold our duty to care for all patients, even those unable to receive critical care interventions. To enact this triage plan, a triage decision support protocol, infrastructure, processes, legal and regulatory protections, and training5Christian M.D. Sprung C.L. King M.A. et al.Triage: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146: e61S-e74SAbstract Full Text Full Text PDF PubMed Scopus (142) Google Scholar are required, all of which are currently lacking in most institutions and regions. Additionally, there is a need to ensure that patients who do not initially receive critical care resources are still provided the best supportive care possible and are reevaluated, at minimum daily, for consideration of resource allocation as supplies become available. This will result in a sliding scale from crisis to contingency, and flexibility should be anticipated. The absence of a triage system, consistently applied within and between hospitals, may lead to unnecessary deaths, increased moral distress for frontline physicians, and a lack of public confidence in the fairness of scarce resource allocation. It is important to recognize that the initiation of adult triage levels does not itself imply initiation of pediatric triage (or vice versa). However, dependent on the level of impact within the pediatric system, pediatric hospitals will need to consider lower-level triage initiation at a point when adult systems have reached crisis triage, to respect the principles of utility and fairness population-wide. With appropriate critical care surge planning, we hope that the use of a triage plan that limits the delivery of critical care should be rare, but the potential consequences of failing to prepare for this eventuality are serious. Table 1 provides operational steps to implement a triage system within a state, county, or jurisdiction and highlights respective stakeholder responsibilities.Table 1Operational Steps to Implement a Triage SystemSpecific Actions SuggestedStakeholders Responsible1. Inventory of potential ICU resources for a surge in demanda.Physical ventilators and beds (eg, OR, PACU)b.Human resources (staff with ICU training)c.Supplies and space to deliver care (eg, medications, disposable items, PPE, PACU)Individual health-care facilities2. Establish identification triggers for and initiation of triage: as clinical demand reaches crisis stage and that crisis standards of care, including triage, should be initiateda.The decision to initiate triage should be made by an identified regional authority with situational awareness of regional health-care demandsb.Triage must be consistently applied across the region, with documented rationale and oversight by the relevant regional authorityRegional government health authorities (county/state/province/national)Regional or national emergency management authorities (eg, CDC or equivalent, state/province public health department)3. Preparation of a triage systema.Create central triage committee for the region, tasked with coordination and standardization. This should include representation of key stakeholders (medical, nursing, ethics, law, patient and community representatives)b.Identify members of institutional tertiary triage teams and support structuresc.Prepare and distribute training materials to local officials for standardization of implementationPublic health department/ministry of healthLocal hospitals with an ICU4. Agreement on a triage protocol to target resources to those with the greatest incremental benefitRegional health authorities and coalitionsCritical care professional societies and community, along with multistakeholder input5. Consideration of changes to allow limits to the delivery of life-sustaining measures in times of crisis care, and indemnity against litigation for decisions made in accordance with the triage policya.Options include a modification or waivers of existing requirements through legislative means, an order through the Public Health Act, or through emergency powersRegional health authority (ie, state health commissioner, provincial health minister)Regional justice authority (ie, attorney general, governor)6. Standards of carea.Modify end-of-life care policies to indicate that the standard of care in a pandemic is to triage patients according to an accepted plan, and that consent is not required to implement treatment decisions taken according to that planb.Ensure that patients unable to receive invasive life-sustaining therapies (eg, mechanical ventilation) are provided the best available care under the circumstances (eg, supplemental oxygen through another route, palliative care, family support)c.Clear clinical guidelines for medical management of people with respiratory failure, including palliative measuresd.Standardized communication tools (eg, sensitive information sheets) to inform members of the public about triage decisions and the rationale behind themState/provincial physician licensing boardCritical care/palliative care community7. Family and societal supporta.Transparency with the public about triage processesb.Communication plans with the public (telephone hotlines, online resources) to ensure that information is readily availablec.Work to preserve the integrity of family units, especially in cases of young children and during end-of-lifed.Ensure support for grieving familiesInstitutional social work, mental health, and palliative care servicesConsideration of COVID-19 hospice services8. Health-care worker supporta.A systematic communication plan with the reasons for triage system activation, training on its use, and companion decision support tools to ensure consistent implementation is essentialb.Triage decisions must be made collaboratively, using a team-based approach that includes the designated triage officer, providers directly assigned to care for individual patients, with support from hospital ethics and palliative care experts when necessaryc.A systematic approach to support health-care workers, including incident debriefing, resiliency skills, and services to provide emotional support must be implemented in advance of triage system activationRegional health authorities and attorney general, in collaboration with regional critical care leaders and ICU directorsIndividual institutions9. Pediatric considerationsa.Concentrate care for children at pediatric centers to preserve necessary pediatric systems, including accepting any pediatric transfers, even ones for whom they may not typically careb.Increasing pediatric age thresholds to 21, 25, or 30 years iteratively as surge requires (as long as no adult comorbidities exist that are not consistent with pediatric critical care practice)a.concentrate pediatric care in pediatriLocal health-care coalitionsCDC = Centers for Disease Control and Prevention; COVID-19 = novel 2019 coronavirus disease; OR = operating room; PACU = post-anesthesia care unit; PPE = personal protective equipment. Open table in a new tab CDC = Centers for Disease Control and Prevention; COVID-19 = novel 2019 coronavirus disease; OR = operating room; PACU = post-anesthesia care unit; PPE = personal protective equipment. COVID-19 is caused by a novel coronavirus that can cause severe acute respiratory illness. Early experience with the virus in China and Italy suggests that the virus has a community symptomatic attack rate of COVID-19 of up to 30% (with approximately double that number of SARS-CoV-2 infections because up to one-half of cases appear to be asymptomatic or paucisymptomatic). Of these, as many as 5% to 25% may require hospital admission, 5% to 8% may require ICU admission, and 2% to 4% may require mechanical ventilation for acute respiratory failure. For example, in the greater New York City metropolitan area alone (with a population of 8.4 million people), a community attack rate of 35% (ie, a symptomatic attack rate of 17.5%), leading to 1.3 million people with varying levels of disease from now until midsummer, could generate approximately 88,000 total hospitalizations and 13,000 ICU admissions under a scenario in which 7% of all affected people require hospitalization and 14% of those require critical care beds. Under a more severe scenario (20% hospitalized and 24% to ICU, rates now seen during the week of March 23, 2020, at New York City hospitals), this could lead to up to 190,000 hospitalizations and 58,000 ICU admissions over the course of the pandemic, with a peak concurrent ICU census of approximately 22,000 before summer. At baseline, the United States has approximately 68,000 adult and 5,000 PICU beds, a per capita ICU bed availability that exceeds most other countries.6Society of Critical Care MedicineUnited States resource availability for COVID-19.https://sccm.org/Blog/March-2020/United-States-Resource-Availability-for-COVID-19?_zs=jxpjd1&_zl=w9pb6Date accessed: March 25, 2020Google Scholar Clearly, either scenario is likely to vastly overwhelm any current health system, as is occurring in Italy and elsewhere. Triage is the course of action that we take when we have exhausted our ability to expand our critical care resources, that is, to surge. Surge capacity refers to the ability of a hospital or other health-care system to expand its normal operating capacity in the setting of an emergency. Surge capacity includes the key features of staff, space, supplies, and systems with communications as a critical fifth feature. All five of these elements are necessary to permit hospitals to surge effectively in disasters. The Task Force for Mass Critical Care3Hick J.L. Einav S. Hanfling D. et al.Surge capacity principles: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146: e1S-e16SAbstract Full Text Full Text PDF PubMed Scopus (114) Google Scholar provided a classification system for differing levels of surge response in their 2014 guidelines on the management of the critically ill during disasters and pandemics. A hospital should be able to increase its critical care capacity by approximately 20% above its normal limitations. This level would be implemented in major mass casualty incidents that trigger activation of the hospital emergency operations plan. Most facilities should be able to achieve this level of response using existing staffing and resources, including strategies such as cancellation of elective procedures and transferring of appropriate patients out of ICUs. This level would be used during a disaster whose medical demands significantly exceeded routine hospital and community resources. At this level, a hospital will expand its critical care capacity by up to 100%, in part through modification of existing spaces and expanding the use of certain staff members. For example, critical care services may be provided in a postanesthesia care unit, stepdown unit, or other high-dependency area with cross-training of staff under the direction of critical care team members. Ventilators intended for the operating room, noninvasive ventilation, or transport can be repurposed to augment the overall ventilator supply. At this level of surge response, it can be expected that medical care will be at or near the predisaster prevailing community standard. This level would be implemented in catastrophic situations, such as suggested by the current COVID-19 modeling, that result in a significant impact on the standard of medical care that can be provided. Severe limitations of space, staff, and supplies would not allow hospitals to provide the usual standard of medical care. At this level, hospitals and communities will need to consider triage principles. The numbers provided are a construct, not absolute rules. As the balance of resources vs demand shifts over time during an emergency, the degree of the surge response and any necessary triage will shift as well (Fig 1). Shortages of trained staff, ventilators, or personal protective equipment (PPE) are very real threats in the current pandemic and will likely be triggers for shifting to triage and crisis standards of care if they should occur. As such, we need to have an accurate inventory of those resources, understanding that the limitations would likely be staff rather than ventilators or space; however, the ongoing experiences in New York suggest that all three may easily be in short supply. However, the early experience in Italy, which has roughly the same number of ICU beds and ventilators per capita as many other developed countries, indicates that our current critical care resources are insufficient to manage a similar outbreak. A number of pandemic triage plans have already been proposed for viral respiratory illness and are outlined in a recent overview on triage.7Christian M.D. Triage.Crit Care Clin. 2019; 35: 575-589Abstract Full Text Full Text PDF PubMed Scopus (40) Google Scholar When the demand for critical care overwhelms the resources available, a resource allocation plan is essential to deliver both the greatest benefit to the greatest number of people, and to maintain the function of the health-care system and prevent random or otherwise inequitable distribution of scarce resources. Triage require us to accept that some individuals will not receive critical care resources which might have been dedicated to their care under normal circumstances, whereas some individuals will have critical care interventions withdrawn if they fail to improve. Although as yet untested in practice, modeling studies evaluating predicted mortality in pandemics have demonstrated that more people will die because of lack of critical care resources than would have died if triage systems were implemented.8Gall C. Wetzel R. Kolker A. Kanter R.K. Toltzis P. Pediatric triage in a severe pandemic: maximizing survival by establishing triage thresholds.Crit Care Med. 2016; 44: 1762-1768Crossref PubMed Scopus (10) Google Scholar,9Kanter R.K. Would triage predictors perform better than first-come, first-served in pandemic ventilator allocation?.Chest. 2015; 147: 102-108Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar Without a triage plan, patients will receive critical care resources by random chance or a first-come, first-serve basis, likely leading to overall worse outcomes across a population and more individuals being denied critical care. A triage system requires an ethical basis, which we summarize in Figure 2.10University of Toronto Joint Centre for Bioethics Pandemic Influenza Working GroupStand on Guard for Thee. Ethical Considerations in Preparedness Planning for Pandemic Influenza. University of Toronto, Toronto, ON2005Google Scholar Limiting and withdrawing critical care resources are justified by the utilitarian principle of providing the greatest good to the greatest number of people. Although the general principle of saving the most lives possible holds true in any system, the decisions of identifying which patients to prioritize for access to critical care will be difficult. A first-come, first-served model of triage has the advantage of simplicity but will exclude patients who lack transportation or easy access to care. A system based on age alone, with mechanical ventilation denied to patients over a given age cutoff, does not account for differences in baseline mortality risk because of underlying health. Communities may choose to prioritize to key groups, to include health-care workers (HCWs), first responders, research volunteers, or others who are either perceived as risking their own safety for the public's benefit or who have a special role in pandemic response; however, strict definitions of who is included in these key groups and the social utility of such preferences remain unresolved. Children and pregnant women may receive special priority in other schema, with the concept of saving not only the most lives but also the greatest number of years of life.11Emanuel E.J. Persad G. Upshur R. et al.Fair allocation of scarce medical resources in the time of Covid-19.N Engl J Med. 2020; 382: 2049-2055Crossref PubMed Scopus (1894) Google Scholar,12Truog R.D. Mitchell C. Daley G.Q. The toughest triage — allocating ventilators in a pandemic.N Engl J Med. 2020; 382: 1973-1975Crossref PubMed Scopus (478) Google Scholar All of these must be taken in consideration, and different cultural priorities will vary between (and within) different countries. This paper is inadequate to answer these questions for a given community; sample triage protocols are available on the CHEST website for review and guidance. These decisions to implement a triage system should be driven by the inability of regional health systems to deliver care to all critically ill patients because of an overwhelming surge in demand that reaches crisis levels. The triage protocol we are referring to in this case is for tertiary triage, which takes place at an acute care hospital when deciding whether or not to admit for critical care services.5Christian M.D. Sprung C.L. King M.A. et al.Triage: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146: e61S-e74SAbstract Full Text Full Text PDF PubMed Scopus (142) Google Scholar In a broad sense, patients who present for tertiary triage are going to fit into one of three categories: (1) too well to benefit from critical care, (2) too sick to benefit from critical care because of severe underlying illness or a poor likelihood of surviving their hospitalization, or (3) sick enough to benefit from critical care. The goal of triage protocols is not to exclude categories of patients based on age or underlying disease, and protocols that explicitly exclude patients based on a single criterion alone may run afoul of antidiscrimination laws in many jurisdictions. Rather, the goal of a triage protocol is to maximize the use of critical care resources for patients in the third category. These categories apply to all patients presenting with critical illness under crisis standards of care, not just those infected with SARS-CoV-2.13Christian M.D. Hawryluck L. Wax R.S. et al.Development of a triage protocol for critical care during an influenza pandemic.CMAJ. 2006; 175: 1377-1381Crossref PubMed Scopus (262) Google Scholar Although we must recognize that patients less likely to benefit from critical care may not be provided those services and interventions under a triage system, reallocation may occur as resources and demand change. The best available epidemiologic data, combined with expert input, will be required to create triage protocols that reflect COVID-19-specific mortality and resource utilization predictions. Although the use of acute illness scores, such as the Sequential Organ Failure Assessment (SOFA) score, were proposed for previous pandemic triage plans, a growing body of evidence suggests such scoring systems are unlikely to predict critical care outcomes with sufficient accuracy,14Khan Z. Hulme J. Sherwood N. An assessment of the validity of SOFA score based triage in H1N1 critically ill patients during an influenza pandemic.Anaesthesia. 2009; 64: 1283-1288Crossref PubMed Scopus (56) Google Scholar,15Zygun D.A. Laupland K.B. Fick G.H. Sandham J.D. Doig C.J. Limited ability of SOFA and MOD scores to discriminate outcome: a prospective evaluation in 1,436 patients.Can J Anaesth. 2005; 52: 302-308Crossref PubMed Scopus (52) Google Scholar in particular patients suffering from COVID-19,16Zhou F. Yu T. Du R. et al.Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study.Lancet. 2020; 395: 1054-1062Abstract Full Text Full Text PDF PubMed Scopus (17387) Google Scholar, 17Yang X. Yu Y. Xu J. et al.Clinical course and outcomes of critically ill patients with SARS-CoV-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study [published online ahead of print].Lancet Respir Med. 2020; 8: 475-481Abstract Full Text Full Text PDF PubMed Scopus (6491) Google Scholar, 18Zhang G, Hu C, Luo L, et al. Clinical features and outcomes of 221 patients with COVID-19 in Wuhan, China [published online ahead of print]. medRxiv.Google Scholar, 19Xu Y, Xu Z, Liu X, et al. Clinical findings in critical ill patients infected with SARS-Cov-2 in Guangdong Province, China: a multi-center, retrospective, observational study [published online ahead of print]. medRxiv. 2020.03.02.20030452. doi: https://doi.org/10.1101/2020.03.02.20030452. Accessed June 10, 2020.Google Scholar or be a useful basis for triage decisions based on the current protocol cut points.13Christian M.D. Hawryluck L. Wax R.S. et al.Development of a triage protocol for critical care during an influenza pandemic.CMAJ. 2006; 175: 1377-1381Crossref PubMed Scopus (262) Google Scholar,20Cheung W. Myburgh J. Seppelt I.M. et al.Development and evaluation of an influenza pandemic intensive care unit triage protocol.Crit Care Resusc. 2012; 14: 185-190PubMed Google Scholar,21Cheung W.K. Myburgh J. Seppelt I.M. et al.A multicentre evaluation of two intensive care unit triage protocols for use in an influenza pandemic.Med J Aust. 2012; 197: 178-181Crossref PubMed Scopus (23) Google Scholar The prognostic accuracy of SOFA varies across its range of scores, with greater variability and less accuracy at lower scores than at higher scores, and is not immediately applicable to all disease states: a patient with sepsis may have a SOFA score of 4 and a low mortality risk, for example, whereas a patient with an intracranial hemorrhage and a Glasgow Coma Scale score of 3 could share this SOFA score of 4 but have a very high risk of death. Potentially subjective elements, such as the dose of vasopressor administered or the assessment of Glasgow Coma Scale during sedation breaks, are subject to physician judgment and are affected by drugs and other interventions.22Christian M.D. Hamielec C. Lazar N.M. et al.A retrospective cohort pilot study to evaluate a triage tool for use in a pandemic.Crit Care. 2009; 13: R170Crossref PubMed Scopus (38) Google Scholar Because outcomes at differing SOFA scores vary across studies and are generally absent in the context of crisis standards of care, system-level data are necessary to guide selection of threshold values. All of these factors combine to raise a number of logistical and ethical concerns regarding the use of the SOFA score in a triage algorithm. Therefore, we propose triage protocols that are not solely dependent on SOFA (or another single scoring tool) because SOFA is unlikely to be adequate in and of itself for triage decisions. It is important to mention that any scoring system at this stage of the pandemic will need to be pragmatic and combine other predictors of ICU mortality, such as disease-specific indicators for non-COVID-19 conditions, frailty scores, comorbidity indices, and physician judgment as best possible. This will need to be balanced against the need for a triage scoring tool that is actionable: complex enough to provide prognostic information with acceptable accuracy, but simple enough to be implemented in a timely manner. As our knowledge of COVID-19 increases, it is likely that better prognostic scoring tools will be developed; when this occurs, triage systems should incorporate these into their protocols to improve our prediction of critical care outcomes and mitigate the limitations of physiological indices in isolation. Periodic reassessment of patients is a necessary part of any triage algorithm, to assess for clinical improvement, deterioration, or any other changes that affect prognosis. COVID-19 illness seems to last longer than influenza, suggesting that reassessments at 48 and 120 h noted in earlier triage protocols5Christian M.D. Sprung C.L. King M.A. et al.Triage: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.Chest. 2014; 146: e61S-e74SAbstract Full Text Full Text PDF PubMed Scopus (142) Google Scholar,13Christian M.D. Hawryluck L. Wax R.S. et al.Development of a triage protocol for critical care during an influenza pandemic.CMAJ. 2006; 175: 1377-1381Crossref PubMed Scopus (262) Google Scholar are too short to provide an adequa