Critical Care Triage in the Covid-19 Pandemic

In the United States, there soon won’t be enough critical care beds and ventilators to accommodate all the patients who will need them.

A pandemic influenza plan, modeled by Health and Human Services (HHS) in 2005 and updated in 2017, suggested that a moderate pandemic would infect about 64 million Americans with about 800,000 (1.25 percent) needing to be hospitalized and 160,000 (0.25 percent) requiring an ICU bed. The severe scenario could see as many as 1,200,000 patients needing an ICU bed.¹

Based on further data from China and Italy, the novel coronavirus (Covid-19) scenario is much more devastating for the United States. In a moderate Covid-19 pandemic, there would be 16 million ill patients, 960,000 of whom would need to be admitted to the ICU^.2 The Covid-19 severe scenario would involve close to 4 million patients needing critical care services. Data from China suggests that 5 percent of patients infected with SARS-CoV-2 will become critically ill.3 In Lombardy, Italy the proportion of ICU admissions was higher, representing 12% of total positive cases.³ 

The US has approximately 900,000 hospital beds and about 85,000 adult critical care beds. Full-featured ventilators number around 62,000, with an additional 98,700 ventilators that are not full featured. The Strategic National Stockpile has an additional 12,700 ventilators for emergency deployment. These offer basic ventilatory modes^.4 

Based on a single-center observational study from Wuhan, there was a 61 percent twenty-eight-day mortality in patients admitted to the ICU.⁵ Older patients (age>65) with comorbidities and acute respiratory distress syndrome (ARDS) were at greatest risk of death. This is similar to more recent observations from a hospital in Washington state, where the ICU mortality was 67 percent.⁶ Unless the epidemic curve is flattened quickly by social-distancing practices, it’s almost certain that rationing critical care resources will become necessary.

An integral part of critical care training and practice for intensivists involves determining which patients can and cannot benefit from ICU care. Therefore, intensivists and the critical care team are the best equipped to manage these difficult triage decisions in the face of this pandemic. Many difficult decisions will be unavoidable. Establishing guidelines to evaluate a patient’s specific situation provides a structure for decision making.

Guidelines for Optimizing the Rationing Process

• Driven by ethical principles:  

• • Distributive justice: do greatest good for greatest number with resources available; i.e., save the most lives and life years (those likely to live the longest after treatment). These patients are given highest priority. ²
  • Give priority to the worst off—if consistent with doing the greatest good.
    • Sickest
  • Priority to the youngest (Life Cycle Principle: i.e., give the young opportunity to live through all life cycles).⁷
  • Promote and reward instrumental value; i.e., patients who provide benefit to others receive priority. Use when likelihood of survival is similar (healthcare workers)^.2
  • Random selection: use if chances of survival are similar.
  • First come, first served: not considered when resources are scarce.
  • Social status or ability to pay never considered. 

• Ration care within scientific and legal framework in context of ethical principles noted above
• Decisions need to be transparent, fair, and consistent.
• Public knowledge and acceptance: The community needs to understand what is at stake.
• Implement on regional, not institutional, basis: Government provides policy support.
• Assist providers: institutional provision of guidelines and policies for limiting or withdrawing care.
• Liability protection for providers.
• Convert all ICUs to closed model if not already done and assign triage officer.
• Defer all non-urgent services, including elective procedures.
• Form triage committee that is available immediately to providers to assist in decision making and to help reduce the emotional burden on individuals.⁸
  Members include: 

• • Several respected members of medical staff not involved in patient’s care.
  • Nurses not involved in patient’s care.

• Implement in stepwise fashion—as resources become exhausted, criteria become stricter—best care possible for those with best chance of survival.
• Hold discussions early on with patients and their families regarding their wishes for life support and do not resuscitate (DNR) status in the context of their medical history and chances of survival should they become critically ill.
• Active palliative care service involved.
• Hospital ethics committee available for consultation.

Guidelines for Limiting Care

• Criteria for the rationing of care depend on the numeric assessment of probability of survival and rely predominantly on clinical variables. These include:

• • Respiratory failure/ARDS, shock, and multisystem organ failure (MSOF), particularly in elderly patients (with or without Covid-19) whose chances of survival are often poor despite best efforts.
  • High potential for death and prolonged ventilation in patients with prior severe chronic organ dysfunction; for example, end-stage heart failure, end-stage chronic obstructive pulmonary disease (COPD) or interstitial fibrosis, metastatic lung cancer, chronic, severe liver disease.
  • Use Sequential Organ Failure Assessment (SOFA) score and its trajectory over the first forty-eight to seventy-two hours of ICU care to assist in severity of illness assessment. A score above 12 would preclude offering mechanical ventilation. ^7,9,10
  • Periodic reassessment of patients on ventilatory support. Removal, if status is not improving, to make this resource available to other patients more likely to benefit. ⁸

It will be gut wrenching for physicians and their critical care teams to make the decision to limit care to patients who otherwise may have had a reasonable chance for recovery. The emotional impact of these actions cannot be overstated. Hospitals should provide all elements of psychological and physical support available to these health care workers during normal times, but especially when rationing or limiting care to critically ill patients becomes necessary.

References

1 - US Department of Health and Human Services, Pandemic Influenza Plan: 2017 Update, Washington, DC, available at: https://www.cdc.gov/flu/pandemic-resources/pdf/pan-flu-report-2017v2.pdf.

2 – Emanuel, E.J., Govind, J., Upshur, R., et al., “Fair Allocation of Scarce Medical Resources in the Time of Covid-19,” N Engl J Med (March 23, 2020), available at: https://www.nejm.org/doi/full/10.1056/NEJMsb2005114.

3- Grasselli, G., Pesenti, A., & Cecconi, M., “Critical Care Utilization for the Covid-19 Outbreak in Lombardy, Italy: Early Experience and Forecast During an Emergency Response,” JAMA (March 13, 2020), available at: https://jamanetwork.com/journals/jama/fullarticle/2763188.

4 – Halpern, N.A., & Kay, S.T., “United States Resource Availability for Covid-19,” Society of Critical Care Medicine (revised March 19, 2020), available at: https://sccm.org/Blog/March-2020/United-States-Resource-Availability-for-COVID-19.

5 – Yang, X., Yuan, Y., Shu, H., et al., “Clinical Course and Outcomes of Critically Ill Patients with SARS-CoV-2 Pneumonia in Wuhan, China: a Single-Centered Retrospective, Observational Study,” Lancet Respir Med. (February 24, 2020), available at: https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30079-5/fulltext.

6 – Arentz, M., Yim, E., Klaff, L., et al., “Characteristics and Outcomes of 21 Critically Ill Patients with Covid-19 in Washington State,” JAMA (March 19, 2020), available at: https://www.ncbi.nlm.nih.gov/pubmed/32191259.

7 – White, D.B., Katz, M.H., Luce, J.M., & Lo, B., “Who Should Receive Life Support During a Public Health Emergency? Using Ethical Principals to Improve Allocation Decisions,” Ann Intern Med. (January 20, 2009), available at: https://www.ncbi.nlm.nih.gov/pubmed/19153413.

8 – Truog, R.D., Mitchell, C., & Daley, G.Q., “The Toughest Triage – Allocating Ventilators in a Pandemic,” N Engl J Med. (March 23, 2020), available at: https://www.nejm.org/doi/full/10.1056/NEJMp2005689.

9 – Ferreira, F., Bota, D.P., Bross, A., et al., “Serial Evaluation of SOFA score to Predict Outcome in Critically Ill Patients,” JAMA (October 10, 2001), available at: https://www.ncbi.nlm.nih.gov/pubmed/11594901

10 – Jones, A.E., Trzeciak, S., & Kline, J.A., “The Sequential Organ Failure Assessment Score for Predicting Outcome in Patients with Severe Sepsis and Evidence of Hypoperfusion at the Time of Emergency Department Presentation,” Crit Care Med. (May 2009): 37(5), available at: https://www.ncbi.nlm.nih.gov/pubmed/19325482.

The views and opinions expressed in this article are those of the author and do not necessarily reflect the opinions, position, or policy of Berkeley Research Group, LLC or its other employees and affiliates.