Strains on Critical Care Capacity Associated with Increased Mortality among VA Patients Admitted to an ICU for COVID-19
BACKGROUND:
The association between COVID-19 critical care strain and mortality has not been examined. This observational cohort study sought to determine whether COVID-19 mortality was associated with COVID-19 Intensive Care Unit (ICU) strain. Using VA data, investigators identified 8,516 Veterans with COVID-19 who were admitted to one of 88 VA hospitals between March and August 2020 (follow-up period thru November 2020). The main outcome was all-cause mortality through 30-days post discharge. Investigators also assessed comorbid conditions, healthcare use, procedures, and laboratory data. Two measures of COVID-19 critical care strain were used: ICU-load and ICU-demand. "COVID-19 ICU-load" described how the critically ill COVID-19 caseload compared with the ICU bed capacity. "COVID-19 ICU-demand" described whether the patient was admitted during a period of peak COVID-19 ICU caseload, defined as the mean number of ICU patients with COVID-19 during a patient's hospital stay divided by the maximum number of ICU patients with COVID-19 at that facility during the period March to August 2020.
FINDINGS:
- Mortality among hospitalized patients with COVID-19 declined significantly from early in the pandemic through summer 2020: March, 23%; April, 25%; May, 16%; June, 14%; July, 13%; and August, 13%.
- Strains on critical care capacity due to peak COVID ICU case-load were associated with increased COVID-19 mortality. ICU patients with COVID-19 had a two-fold increased risk of death if treated during periods where COVID-19 ICU-demand was 75-100% of peak demand (“rush hour”) compared to periods below 50% of peak.
- No association between COVID-19 ICU-demand and mortality was observed for non-ICU patients with COVID-19.
IMPLICATIONS:
- Public health officials and hospital administrators should monitor rising COVID-19 ICU case counts relative to earlier peaks to prepare for possible effects on patient outcomes and seek ways to reduce ICU strain. In addition, it is imperative that research be conducted to further understand the degree to which patient characteristics (e.g., disease severity) or facility issues (e.g., staffing) contribute to the association between COVID-19 ICU strain and poor patient outcomes among critically ill patients with this virus.
LIMITATIONS:
- Findings should not be interpreted as a statement on scarcity of critical care or mechanical ventilation; there was no data to suggest that patients lacked either.
- Social determinants of health (e.g., income, education, housing), which may contribute to COVID-19 mortality, were not included in this study.
- ICU staffing changes during the study period were not assessed, nor was the degree to which facilities expanded ICU capacity during the pandemic.
AUTHOR/FUNDING INFORMATION:
This study was funded by HSR&D’s Quality Enhancement Research Initiative (QUERI). Drs. Bravata, Perkins, and Myers are part of Precision Monitoring to Transform Care ( PRISM) UERI, and Drs. Bravata and Myers also are part of HSR&D’s Center for Health Information and Communication (CHIC)
Bravata D, Perkins A, Myers L, et al. Association of Intensive Care Unit Patient Load and Demand with Mortality Rates in U.S. Department of Veterans Affairs Hospitals During the COVID-19 Pandemic. JAMA Network Open. January 19, 2021;4(1):e2034266.