Operationalizing Crisis Standards of Care: The Potential Hazards of Relying on SOFA Scores for Resource Allocation

Operationalizing Crisis Standards of Care: The Potential Hazards of Relying on SOFA Scores for Resource Allocation

By: Brandon Corbett Walsh, MD, MBE, and Aloke Chakravarti, MD, FCCP
Disaster Response and Global Health Network
Published: April 23, 2021

Disaster preparation is a critical part of every hospital and community. When demand for resources such as hospital beds, providers, or equipment (the traditional pillars of “space, staff, and stuff”) overwhelms current supply, hospitals utilize proportional strategies to minimize the impact this strain has on patient care. These strategies are codified as conventional, contingency, and crisis standards of care.

The global COVID-19 pandemic strained numerous health care systems, causing some hospitals to operate under contingency and even crisis standards of care. In circumstances that require crisis standards of care, scarce hospital resources may need to be rationed. This stems from the utilitarian bioethical principle of doing the greatest good for the most people. The distribution of health care resources, in this context, transitions from conventional resource allocation (individual medical need or the rule of rescue) to prioritizing the public health of the community and doing the greatest good for the greatest number of people.

The core of such a utilitarian resource allocation policy requires a prognostication model that aims to select individuals who are most likely to survive, but does so in a fair, transparent, and consistent manner that does not worsen existing health disparities. To date, however, no prognostication tool exists to predict mitigated outcomes of critical illness during a pandemic.

What the Literature Says: How Helpful Is the SOFA Score in Predicting Mortality?

Initial studies suggested that an admission Sequential Organ Failure Assessment (SOFA) score might be an acceptable predictor of mortality (AUC 0.75-0.89).^1-5 The AUC statistic is used to determine if a test can distinguish between two groups; in this case, survivors and nonsurvivors. An AUC of 0.5 suggests that a test cannot discriminate between groups, whereas >0.8 is excellent. An AUC of 0.7 to 0.8 suggests acceptable performance of a test.

As a result, 58% of state protocols in the US⁶ and 62.1% of published triage protocols identified in a separate study⁷ utilize the SOFA score as a core component of their resource allocation guidelines within crisis standards of care. At the same time, the SOFA score has been used to employ the necessary principle of utilitarianism or “stewardship,” as 55.6% of protocols exclude patients from receiving critical care when their SOFA scores exceed 11.⁷

Unfortunately, evidence demonstrates that a SOFA score may not be predictive of hospital mortality⁷ in the setting of an infectious disease outbreak, including a recent analysis of those on mechanical ventilation due to COVID-19 yielding an AUC of only 0.59.⁸ This has potentially negative consequences for resource allocation because an ineffective prognostication model might potentiate mortality as a result of directing critical care resources away from patients who would have otherwise survived and toward those who ultimately did not survive despite having received critical care.

Additionally, it should be noted that many mortality prediction models, including the SOFA score, have not been validated for resource allocation itself, nor for prognostication in the diseases necessitating their use.⁹ Furthermore, as experienced during COVID-19, the use of sedatives, paralytics, or prone positioning may complicate the interpretation of the respiratory and neurological components of a SOFA score.

How Do We Prepare for the Next Pandemic?

In situations where resources cannot be strategically shifted within institutions, shared between institutions, or when patients cannot be transferred out of a disaster zone to lessen the resource strain, (ie, where the usual surge capacity is limited), it may be necessary to ration scarce resources. Prioritizing resource stewardship to a greater degree brings to bear some ethical principles that many clinicians do not ordinarily have to exercise.

The use of objective scoring systems achieves impartiality, preserves fairness, promotes transparency with the community, maintains reproducibility between providers, and reduces unconscious bias on the part of decision makers. It may also minimize the decision paralysis and moral injury among clinicians that likely accompanies such determinations. Such scores may require further augmentation to strive for equity and not perpetuate existing health disparities^10,11 or to better reflect community values.

While further research should be devoted toward the development of accurate prognostic models of critically ill patients and their performance in crisis standards of care guidelines, it may be helpful to focus on improving cross-institutional communication. Health systems have demonstrated the need to develop processes to permit patient and equipment transfer between institutions in order to reduce the impact of regional shortages in critical care resources (“load-leveling”) and thus avoid the need to implement crisis standards.¹²

This literature review highlights some pitfalls and future benchmarks for resource allocation guidelines in crisis standards of care. Reliance on disease-specific scoring systems may result in inefficient resource allocation in some mass casualty incidents. Crisis standards of care require a paradigm shift, where the four basic ethical principles are balanced against the principle of utilitarianism, or stewardship of resources. Well-constructed, transparent, published triage and stewardship protocols for crisis standards of care at the health system or regional level are essential for the equitable delivery of health care during disasters and pandemics.

References

1. Romney D, Fox H, Carlson S, et al. Allocation of scarce resources in a pandemic: a systematic review of US state crisis standards of care documents. Disaster Med Public Health Prep. 2020;14(5):677-683.
2. Raith EP, Udy AA, Bailey M, et al. Prognostic accuracy of the SOFA score, SIRS criteria, and qSOFA score for in-hospital mortality among adults with suspected infection admitted to the intensive care unit. JAMA. 2017;317(3):290-300.
3. Liu S, Yao N, Qiu Y, et al. Predictive performance of SOFA and qSOFA for in-hospital mortality in severe novel coronavirus disease. Am J Emerg Med. 2020;38(10):2074-2080.
4. Seymour CW, Liu VX, Iwashyna TJ, et al. Assessment of clinical criteria for sepsis: for the third international consensus definitions for sepsis and septic shock (sepsis-3). JAMA. 2016;315(8):762-774.
5. Moreno R, Vincent JL, Matos R, et al. The use of maximum SOFA score to quantify organ dysfunction/failure in intensive care. Results of a prospective, multicentre study. Working Group on Sepsis related Problems of the ESICM. Intensive Care Med. 1999;25(7):686-696.
6. Piscitello GM, Kapania EM, Miller WD, et al. Variation in ventilator allocation guidelines by US state during the coronavirus disease 2019 pandemic: a systematic review. JAMA Netw Open. 2020;3(6):e2012606.
7. Fiest KM, Krewulak KD, Plotnikoff KM, et al. Allocation of intensive care resources during an infectious disease outbreak: a rapid review to inform practice. BMC Med. 2020;18(1):404.
8. Raschke RA, Agarwal S, Rangan P, et al. Discriminant accuracy of the SOFA score for determining the probable mortality of patients with COVID-19 pneumonia requiring mechanical ventilation. JAMA. 2021;325(14):1469-1470.
9. Vincent JL, Moreno R, Takala J, et al. The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. On behalf of the Working Group on Sepsis-Related Problems of the European Society of Intensive Care Medicine. Intensive Care Med. 1996;22(7):707-710.
10. White DB, Lo B. Mitigating inequities and saving lives with ICU triage during the COVID-19 pandemic. Am J Respir Crit Care Med. 2021;203(3):287-295.
11. Ashana DC, Anesi GL, Liu VX, et al. Equitably allocating resources during crises: racial differences in mortality prediction models. Am J Respir Crit Care Med. 2021.
12. Biddison ELD, Gwon HS, Schoch-Spana M, et al. Scarce resource allocation during disasters: a mixed-method community engagement study. Chest. 2018;153(1):187-195.

Brandon Corbett Walsh, MD, MBE

• Pulmonary and Critical Care Fellow at New York University
• Interests include communication near the end of critical illness, disaster medicine, and the intersection of critical care and bioethics

Aloke Chakravarti, MD, FCCP

• Assistant Professor of Pulmonary and Critical Care Medicine at the Icahn School of Medicine at Mount Sinai, NYC
• Disaster Response and Global Health Network Steering Committee Member
• Interests include pulmonary vascular disease, prehospital and disaster medicine, and bioethics

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Aerosolization Risks of Noninvasive Ventilation in the Era of COVID-19

Aerosol Generation Risk of Chest Physiotherapy and Airway Clearance Techniques in Patients With COVID-19 

Timing of Intubation in Patients With COVID-19