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Who Should Receive Life Support During a Public Health Emergency? Using Ethical Principles to Improve Allocation Decisions

Douglas B. White, MD, MAS; Mitchell H. Katz, MD; John M. Luce, MD; and Bernard Lo, MD
[+] Article, Author, and Disclosure Information

From the University of California, San Francisco, School of Medicine; University of California, San Francisco; San Francisco Department of Public Health; and San Francisco General Hospital, San Francisco, California.

Potential Financial Conflicts of Interest:Consultancies: B. Lo (Centers for Disease Control and Prevention Ethics Subcommittee to Advisory Committee to Director).

Grant Support: By grant KL2 RR024130 from the National Center for Research Resources, a component of the NIH and NIH Roadmap for Medical Research and by the Greenwall Foundation.

Requests for Single Reprints: Douglas B. White, MD, MAS, University of California, San Francisco, Program in Medical Ethics, 521 Parnassus Avenue, Suite C-126, Box 0903, San Francisco, CA 94143-0903; e-mail, dwhite@medicine.ucsf.edu.

Current Author Addresses: Drs. White and Lo: University of California, San Francisco, Program in Medical Ethics, 521 Parnassus Avenue, Suite C-126, Box 0903, San Francisco, CA 94143-0903.

Dr. Katz: 101 Grove Street, Room 308, San Francisco, CA 94102.

Dr. Luce: San Francisco General Hospital, 1001 Potrero Avenue, Room 5 K1, San Francisco, CA 94110.

Ann Intern Med. 2009;150(2):132-138. doi:10.7326/0003-4819-150-2-200901200-00011
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A public health emergency, such as an influenza pandemic, will lead to shortages of mechanical ventilators, critical care beds, and other potentially life-saving treatments. Difficult decisions about who will and will not receive these scarce resources will have to be made. Existing recommendations reflect a narrow utilitarian perspective, in which allocation decisions are based primarily on patients' chances of survival to hospital discharge. Certain patient groups, such as the elderly and those with functional impairment, are denied access to potentially life-saving treatments on the basis of additional allocation criteria. We analyze the ethical principles that could guide allocation and propose an allocation strategy that incorporates and balances multiple morally relevant considerations, including saving the most lives, maximizing the number of “life-years” saved, and prioritizing patients who have had the least chance to live through life's stages. We also argue that these principles are relevant to all patients and therefore should be applied to all patients, rather than selectively to the elderly, those with functional impairment, and those with certain chronic conditions. We discuss strategies to engage the public in setting the priorities that will guide allocation of scarce life-sustaining treatments during a public health emergency.





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Submit a Comment/Letter
Ethical issue: preparation for public health emergency
Posted on January 20, 2009
Allan R. Glass
Conflict of Interest: None Declared

To the Editor:

To me, this thought-provoking discussion of the ethics of life-support allocation during a public health emergency raises an even bigger issue: What is the ethical context of not allocating sufficient resources in advance so that these wrenching ethical decisions would not be necessary? The scenarios for pandemic flu are well-recognized and its consequences studied extensively; is it unethical for the government and society not to spend money to develop an inexpensive temporary respirator, to stockpile such respirators (as we do drugs such as oseltamivir), to modify auditoriums so they can serve as temporary respiratory ICU's, to develop protocols so that respiratory care providers can efficiently handle large numbers of patients on ventilators, and so forth?

Given that a future flu pandemic, like past ones, is likely to hit many young people without comorbid conditions, people who could have a good chance of survival if provided temporary respiratory support, shouldn't we be taking the steps that would enable the provision of care to all or most and thus obviate the type of ethical problems described in the paper? As our government ponders a massive infrastructure spending program to stimulate the economy and put people back to work, perhaps we should consider this the ideal time for beefing up our public health infrastructure as well.

Conflict of Interest:

None declared

Seven ventilators for 2889 polio victims: the experience in Copenhagen, 1952
Posted on January 28, 2009
John Hansen-Flaschen
University of Pennsylvania
Conflict of Interest: None Declared

White and colleagues propose a strategy based on contemporary moral considerations for allocating a limited number of mechanical ventilators in the event of an influenza pandemic or other comparable public health emergency. Their approach prioritizes patients for life support by summing their scores on three 4-point scales: prognosis for short-term survival based on acute organ dysfunction; prognosis for long-term survival based on assessment of co-morbid conditions, and life stage (age). It is instructive to test this strategy against an actual, well documented public health emergency that unfolded at the dawn of modern respiratory intensive care.

Beginning in July, 1952, 2,899 residents of Copenhagen, Sweden became ill with poliomyelitis (1). The number of patients who required assisted ventilation soon vastly outnumbered the 7 functional negative pressure ventilators on hand. Because most victims were young, had no consequential co-morbid conditions, and initially had a similar prognosis for short term recovery, many may have scored identically on the proposed allocation scale. Thus, application of the strategy suggested by White et. al. might have required a tie-breaking scheme. Also, patients developed respiratory failure sequentially over a period of six months, raising the unsettling question as to whether later victims with higher priority scores should have displaced from life support earlier victims with lower priority scores. Both allocation challenges might occur again if, for example, a pandemic sweeps a large university community.

What did the physicians in Copenhagen do? They improvised and innovated. Among the many solutions devised on the spot was the wide-scale application of manual positive pressure ventilation delivered through cuffed tracheostomy tubes. Altogether, approximately 1500 medical and dental students worked continuously in 6-hour shifts to sustain ventilation for all patients in need by hand-squeezing rebreathing balloons attached to the tracheostomies. This remarkable experience suggests the wisdom of deliberately including in the organization of responders to a public health emergency a multidisciplinary team charged and empowered with overcoming clinical, logistical, financial and legal obstacles to serving as many victims as possible, thereby minimizing the need for an allocation strategy.


1. Wackers, GL. Modern anaesthesiological principles for bulbar polio: manual IPPR in the 1952 polio-epidemic in Copenhagen. Acta Anaesthesiol Scand. 1994; 38:420-431.

Conflict of Interest:

None declared

Allocation of Scarce Resources to Patients Patients who are Permanently Unconsciousness
Posted on February 7, 2009
Mark D Siegel
Yale School of Medicine
Conflict of Interest: None Declared

White and colleagues have proposed a carefully considered algorithm to ensure appropriate use of resources during a public health disaster. Their system should be widely applicable and reflects commonly held values.

The authors understandably acknowledge the difficulty inherent in denying access to specific patient groups. Consequently, their system does not address conditions associated with diminished functional (particularly cognitive) status. However, a just system cannot avoid taking certain conditions into account.

Permanent unconsciousness is an example. Consider two 42 year old women with septic shock and respiratory failure, neither with significant comorbidities that would limit long-term survival. One is a wife and mother of three; the other is permanently unconscious following traumatic brain injury. As I understand it, the authors' "multiprinciple strategy" would not distinguish between these individuals.

Disagreement over the appropriateness of life support in permanently unconscious patients has inspired heated debate (1). Many contend that permanently unconscious patients should not be offered life support, particularly when resources are scarce (2,3). However, these opinions do not necessarily represent a consensus view (4).

Though ethically challenging and emotionally laden, we cannot avoid considering functional status when making allocation decisions, particularly when the patients in question are cognitively and permanently devastated.


1. Annas GJ. "Culture of Life" Politics at the Bedside "” The Case of Terri Schiavo. N Engl J Med. 2005; 352:1710-1715.

2. American Thoracic Society. Withholding and Withdrawing Life-sustaining Therapy. Ann Intern Med. 1991; 115:478-485.

3. Schneiderman LJ, Jecker NS, Jonsen AR. Medical Futility: its Meaning and Ethical Implications. Ann Intern Med 1990; 112:949"“954.

4. Burns JP, Truog RD. Futility: A Concept in Evolution. Chest 2007; 132;1987-1993.

Conflict of Interest:

None declared

The tricky balance of triage.
Posted on February 13, 2009
Michael D Christian
Mount Sinai Hospital, Toronto
Conflict of Interest: None Declared

The perfect tertiary triage protocol for use in a pandemic or mass casualty event has not yet been published. We welcome and congratulate White et al on their contribution to the ongoing dialogue related to tertiary triage (1). However, just as triage is always a balance between available resources and demand; so too must one attempt to strike the right balance among ethical doctrine, evidence, usability, and functionality when developing a triage score. The triage score proposed by White and his colleagues leans in favor of addressing the issues most important in the conceptual world of ethics at the expense of a solution which could be translated into action in the stark reality of a pandemic or disaster.

In an effort to arrive at a very "basic solution" the authors have lost many of the components essential for application of a triage protocol in a disaster. A triage protocol must be easy to use at the bedside (the front end of the protocol), and this often requires the back end of its development and design to be very complex. In White's current proposal, the score is not anchored nor is any action directed. When a triage officer evaluates a patient what does a score of 4, or 6, or 10 mean and how does it relate to their likelihood to survive? If there is only one patient, what is the score compared to or does that patient get the available resource regardless of how unlikely they are to survive? What happens 30 minutes later when another patient arrives but now there is no ventilator, does one re-score all the patients who are on ventilators and take the highest scoring patient off for the new patient? Situational awareness is a challenge in any disaster, knowing every patient's score in the ICU every time a decision has to be made is impractical. What happens if two triage officers are working in different parts of the hospital, how is every patient compared to the other? Color coding and the use of 4 triage categories with pre-defined guides for actions are a tried and tested component of triage protocols. A triage protocol is intended to bring order to chaos early in an event, but there must also be a mechanism to evaluate outcomes and adjust for over or under triage. These components are lacking in White et. al.s' proposal.

We wish to clarify some of the misinterpretations regarding previous triage protocols (2,3). It was stated quite clearly in previous groups' documents hat "employing exclusion criteria should not equate with judgments of whether any one person is "worth saving." We feel that were it possible, EVERY life is "worth saving." The "exclusion criteria" are intended to assist with prioritization of patients during extreme imbalances of need and resources. If the balance improved and there were sufficient resources for all, those who met the exclusion criteria of course would not be restricted from receiving life-sustaining care. In the context of an overwhelming mass casualty event, the issue at hand is balancing the resources required to save one life versus potentially many others. White et al go on to state that we have made a "mistaken assertion that patients with severe co-morbid conditions will always have a bad outcome". Again, this is a misinterpretation of our reasoning. In part the exclusion criteria are related to the likelihood of one-year survival. However, they are more related to the additional quantities of resources that would be required for a person with such severe co-morbidities to survive and as a result would not be available to many others. Under normal circumstances with unlimited supplies, highly trained staff and state of the art care, it may be possible for someone with end-stage organ failure to recover from a critical illness; but these are not the circumstances of a disaster or pandemic. In a disaster there will be a significantly altered level of care (4).

The previously published triage protocols put forth by Ontario, New York State and the Task Force for Mass Critical Care were driven by the best available clinical evidence and guided by ethical principals rather then driven by them. The exclusion criteria were not arbitrarily arrived at and were based upon definitions of end-stage disease states or organ failure as defined by recognized objective criteria, whenever possible. By necessity they refer to specific disease states in order to be objective. Most of the objectiveness of the prior protocols is removed in White et al's proposal by not operationalizing the comorbidities with specific definitions thus opening up the decisions to the complete subjectivity of individual physicians.

Finally, the lack of a ceiling on resource utilization and guidelines for re-triage is a major shortcoming of this proposal. When applying a population approach during a disaster any triage protocol must address the rationing of resources in addition to prioritization. The current protocol, without limits on resources, would allow consumable resources to be depleted quickly early in a pandemic by patients with little or no chance of recovery while at the same time committing non-consumable resources to the patients who present early without offering any mechanism for re-assessment. Placing a limit on how many resources will be committed to any individual is a difficult but necessary component of triage (5).

While the authors have raised some valuable points in their discussion that should lead to reflection and re-evaluation of the current protocols, their proposal lacks many of the features necessary for it to be applied in the field during a disaster or pandemic.


(1) White DB, Katz MH, Luce JM, Lo B. Who should receive life support during a public health emergency? Using ethical principles to improve allocation decisions. Ann Intern Med. 2009;150:132-38.

(2) Christian MD, Hawryluck L, Wax RS, Cook T, Lazar NM, Herridge MS et al. Development of a triage protocol for critical care during an influenza pandemic. CMAJ. 2006;175:1377-81.

(3) Devereaux AV, Dichter JR, Christian MD, Dubler NN, Sandrock CE, Hick JL et al. Definitive care for the critically ill during a disaster: a framework for allocation of scarce resources in mass critical care: from a Task Force for Mass Critical Care summit meeting, January 26-27, 2007, Chicago, IL. Chest. 2008;133:51S-66S.

(4) Rubinson L, Hick JL, Hanfling DG, Devereaux AV, Dichter JR, Christian MD et al. Definitive care for the critically ill during a disaster: a framework for optimizing critical care surge capacity: from a Task Force for Mass Critical Care summit meeting, January 26-27, 2007, Chicago, IL. Chest. 2008;133:18S-31S.

(5) Burkle FM, Jr. Mass casualty management of a large-scale bioterrorist event: an epidemiological approach that shapes triage decisions. Emerg Med Clin North Am. 2002;20:409-36.

Conflict of Interest:

Members of the ACCP Task Force on Mass Critical Care

Allocation of Scarce Resources During Disasters
Posted on February 13, 2009
Tia Powell
Montefiore Medical Center, Albert Einstein College of Medicine
Conflict of Interest: None Declared

Dear Editors,

White, Katz, Luce and Lo offer an interesting and useful critique of existing proposals for allocating critical care resources in public health disasters. We comment as drafters of the New York proposal cited by these authors, a group that included numerous ethicists, clinicians and public health experts and that developed an ethical framework to guide allocation principles. That there are differences in the specific recommendations about allocation is testimony to the difficulty of translating ethical principles into concrete actions in the clinical realm. For instance, we use exclusion criteria before applying a SOFA score, thus barring patients with severe co-morbidities from receiving ventilators in a disaster. White, et. al. calculate SOFA scores and then exclude patients with severe co-morbidities(1). Based on these aspects of the allocation process, both proposals will result in similar groups of patients receiving or being denied access to ventilators. One substantive difference between White et. al.'s proposal and New York's is the explicit use of age as a factor that limits ventilator access. We considered and rejected this option on the grounds that the SOFA score would inherently weigh against the elderly, who tend to have more co-morbidities than the young. However, our own New York state focus group data indicate that community members may prefer a system that enhances ventilator access for the young.

White et. al. raise extremely important concerns, shared by us, about the process of public engagement. They salute the ethical propriety of eliciting public input before devising a plan based on expert opinion. However, they then immediately reject their own advice and propose revisions based on their expertise, without benefit of public input or a consensus group. That leaves unanswered the genuinely difficult question of the proper role and timing for public and expert input in the shaping of public policies, particularly those that refer to technical knowledge, such as survival rates in critical illness and the use of critical care resources. In discussing disaster allocation in dozens of forums across New York State and nationally, we find that clinicians are shocked by our recommendation that all patients be treated equally, i.e. that there be no special priority for health care professionals or other first responders. In contrast, community members not only prefer a system with equal access to the community's resources for all patients, but fear that health professionals will secure a disproportionate share of resources for themselves regardless of the allocation system. We concur that focus groups and other modes of genuine public engagement are critical to the development of just policies. We will continue to work toward these goals and look forward to working with these thoughtful colleagues toward that end.


1. Douglas B. White, Mitchell H. Katz, John M. Luce, and Bernard Lo Who Should Receive Life Support During a Public Health Emergency? Using Ethical Principles to Improve Allocation Decisions Ann Intern Med 2009; 150: 132-138

Conflict of Interest:

Members, NYSDOH/NYS Task Force on Life & the Law Workgroup on the Allocation of Ventilators in an Influenza Pandemic

Considering Life-Years and Age: Another Perspective
Posted on February 20, 2009
Dorothy E Vawter
Minnesota Center for Health Care Ethics
Conflict of Interest: None Declared

We commend White and his colleagues for their cogent suggestions that rationing in public health emergencies is best guided by balancing multiple ethical principles; that age-based rationing may be appropriate; and that ethical guidance should be grounded in robust public engagement (1). The Minnesota Pandemic Ethics Project recently released preliminary ethical frameworks for rationing several types of health-related resources, including mechanical ventilators, in a severe pandemic (2). When rationing ventilators, we agree it is insufficient to focus solely on maximizing the number of people who survive to hospital discharge. Though our ethical guidance shares much in common with White's, some key ethical differences merit mention. White et al. recommend maximizing life-years saved. In stark contrast and for reasons of fairness, we reject rationing based on differences in duration of extended life. Mortality data matched for age and gender signal significant differences in life expectancy for poor persons of color compared with wealthy white Americans. Prioritizing access to a vent by a wealthy, otherwise healthy 30-year-old white woman over a low-income, otherwise healthy 30-year-old American Indian man based on differences in anticipated life expectancy would unfairly reinforce disparities. Public health crises routinely result in disproportionate harm to socially vulnerable groups. We recommend taking reasonable steps to remove access barriers and to avoid exacerbating health disparities.

We agree that it may be permissible at times to consider prioritizing younger persons over older persons, however we recommend attending to age differently. When the number of ventilators available is inadequate to serve everyone with equal clinical need, (e.g., SOFA scores), we recommend a random process or, if Minnesotans generally agree, first prioritizing children before adults and then randomizing among equally situated children. White et al. do not distinguish children from adults; children are lumped with adults up to age 40. They distinguish among adults under age 41, 41-60, 61-74, and 75 and older. We instead propose prioritizing a younger before an older adult only when the difference in age is greater than a specified number of years, e.g., 10 or 20 years. This method protects against a difference in age of a few days being sufficient to prioritize "the younger" adult. Small differences in age are too arbitrary to be a fair way to ration access by individuals with similar clinical need. Clearer methods and richer justifications for considering (or rejecting) age-based rationing are warranted.


(1) Douglas B. White, Mitchell H. Katz, John M. Luce, and Bernard Lo. Who Should Receive Life Support During a Public Health Emergency? Using Ethical Principles to Improve Allocation Decisions. Ann Intern Med 2009;150:132-138.

(2) DE Vawter, JE Garrett, K Gervais, AW Prehn, DA DeBruin, CA Tauer, E Parilla, J Liaschenko and MF Marshall. For the Good of Us All: Ethically Rationing Health Resources in Minnesota in a Severe Influenza Pandemic. [Preliminary Report] Minneapolis: Minnesota Center for Health Care Ethics and University of Minnesota Center for Bioethics (2009). Available at: www.ahc.umn.edu/mnpanflu.

Conflict of Interest:

None declared

Authors' Reply
Posted on March 18, 2009
Douglas B. White
Conflict of Interest: None Declared

We appreciate our colleagues' comments and are heartened to see that our analysis has stimulated further thought among clinicians and policymakers.

We agree with Dr. Glass that government has an ethical obligation to carefully plan for foreseeable public health emergencies, such as pandemicinfluenza. However, because society's resources are limited, it is impossible to fully meet all emergency needs while still allocating adequate resources to competing routine societal needs such as primary care, education, infrastructure, and defense. Public health emergencies remind us of the inevitable need to balance competing considerations when shaping public policy.

Dr. Hansen-Flaschen uses the 1952 poliomyelitis outbreak in Sweden as a "test case" for our multi-principle allocation strategy. He raises the concern that even with a multi-principle allocation system, there may be clusters of patients indistinguishable based on age, prognosis for survival, and life-years saved, requiring a tie-breaking mechanism. This is possible, but not necessarily problematic. If patients are indistinguishable based on the allocation principles set forth as morally relevant, then there is no compelling reason to prioritize any one over the others in the group. We advocate that if such a situation occurs, random allocation should be used to break ties.

Dr. Siegel eloquently argues that individuals with severe functional impairment should receive relatively less prioritization for life support. He also correctly points out that there is deep disagreement in society about whether functional status or social worth are material considerations when allocating scarce resources. This is an emotionally charged social issue. Because public trust and cooperation with restrictive measures will be crucial to a successful public health response, we think including such a controversial criterion that affects a very small, vulnerable patient group may ultimately be more detrimental than beneficial to an effective response. We agree that this is a key issue for robust public engagement.

Powell et al assert that the allocation strategy we propose is similar to theirs because both propose to exclude patients from life support based on certain criteria. We disagree. We argued against categorical exclusion of patients and instead favor assigning a priority score to all who would be eligible to receive life support in routine conditions, then having the cut point for receiving life support determined by the availability of resources.

Powell et al also claim that we have gone against our own recommendation for genuine public engagement by proposing an alternative allocation strategy without first engaging the public. We had no intention to set policy; that is a task for policymaking bodies and officials. Instead, our goal was to inform policymakers and the public about alternative allocation strategies and their ethical implications. Our hope is that the ideas we present will be vigorously discussed during the public engagement process- and ultimately accepted or rejected by informed citizens and policymakers.

Most of the criticisms from Christian et al seem to arise from their misunderstanding of the purpose of our proposal. They fault it for failing to comprehensively address all of the organizational and logistical challenges that will arise during a public health emergency. However, our goal was not to create an organizational protocol. Their group did this admirably (1, 2). We sought to complement their work by providing a clear analysis of the ethical issues at stake when the demand for life support exceeds supply during a public health emergency. We also sought to provide policymakers and the public with an alternative set of allocation criteria that are ethically robust and accompanied by clear justifying arguments, a feature that prior groups' efforts lack. Christian's assertion that our proposed multi-principle allocation strategy is infeasible seems premature. The continuous allocation score our approach yields could be categorized into the familiar 4 color-coded triage categories.

We are not persuaded by Christian's defense of categorical exclusions of certain patient groups from access to life support. He claims that these exclusions are justified because these individuals would have an exceedingly poor prognosis for 1-year survival or would require a highly disproportionate amount of scarce resources in order to survive. They exclude, for example, the very elderly, those with severe cognitive impairment, and those with certain severe co-morbid diseases. However, advanced age alone is not a reliable predictor of poor ICU outcomes or isproportionate resource use (3, 4). Moreover, we are aware of no solid data to support the claim that individuals with severe cognitive disabilities require disproportionately more life support than matched individuals without cognitive disabilities. Most importantly, some of the excluded chronic diseases do not reliably predict poor 1-year outcomes or disproportionate resource use, as illustrated by our case example in Table 1 of the original work.

Christian also criticizes our proposal for allowing a degree of clinical judgment in determining whether a patient has a life limiting co-morbidity. We acknowledge that allowing clinical judgment also opens the door to physician bias. However, there are ample empirical and actuarial data that could inform the development of lists of diseases known to be associated with various degrees of shortened life expectancy. These data could guide the assessment of life limiting diseases in our allocation strategy.

Space constraints prevented us from providing a detailed account of whether life support should be withdrawn from some patients in order to provide it to others with a more favorable allocation score. Several groups have addressed this issue and we agree with their assessment that it will likely be necessary to withdraw life support from patients whose condition worsens considerably, or from those who demonstrate via a time- limited trial that their need for resources will be disproportionate to the needs of others (1, 2).


1. Christian MD, Hawryluck L, Wax RS, et al. Development of a triage protocol for critical care during an influenza pandemic. Cmaj 2006; 175:1377-1381

2. Devereaux A, Dichter JR, Christian MD, et al. Definitive Care for the Critically Ill During a Disaster: A Framework for Allocation of Scarce Resources in Mass Critical Care. CHEST 2008; 133:51S-66S

3. Chelluri L, Mendelsohn AB, Belle SH, et al. Hospital costs in patients receiving prolonged mechanical ventilation: does age have an impact? Crit Care Med 2003; 31:1746-1751

4. Ely EW, Evans GW, Haponik EF. Mechanical ventilation in a cohort of elderly patients admitted to an intensive care unit. Ann Intern Med 1999; 131:96-104

Conflict of Interest:

None declared

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