Study is one of the first to document ICU capacity-mortality association

Strains on demand and decreased intensive care unit (ICU) capacity in U.S. Veteran’s Affairs hospitals early in the Covid-19 pandemic were associated with higher death rates from the disease, new research found.

Among patients with Covid-19 admitted to 88 VA hospitals across the nation in the spring and summer of 2020, ICU treatment during peak Covid-19 caseload times was associated with a nearly 2-fold increased risk for death, compared to treatment during low ICU demand periods.

ICU caseload was found to be consistently and independently associated with Covid-19 ICU mortality in the study, published online Jan. 19 in JAMA Network Open.

The findings suggest that strategies designed to ease ICU strain may lead to lower mortality among patients with severe Covid-19, wrote lead researcher Dawn Bravata, MD, of the Richard L. Roudebush VA Medical Center, Indianapolis, and colleagues.

“Public health officials and hospital administrators may seek to prevent high Covid-19 ICU demand to optimize outcomes for patients with Covid-19,” they wrote.

The researchers noted that, while hospital capacity strain due to increased patient volume is known to be associated with higher ICU mortality in non-pandemic settings, the study is among the first to directly examine ICU mortality during the Covid-19 pandemic.

The observational cohort study included patients with severe acute respiratory syndrome due to confirmed SARS-CoV-2 treated in the VA ICUs from March 1 through Aug. 31, 2020.

Covid-19 ICU load was defined as the mean number of patients with Covid-19 in the ICU during the patient’s hospital stay divided by the number of ICU beds at the facility. Demand was defined as the mean number of patients with Covid-19 in the ICU during the patient’s stay divided by the maximum number of patients with Covid-19 in the ICU.

Of the 8,516 patients with Covid-19 included in the study, 8,014 (94.1%) were men and their mean (SD) age was 67.9 (14.2) years.

Mortality varied over time, with 218 of 954 patients (22.9%) dying in March, 399 of 1,594 patients (25.0%) dying in April, 143 of 920 patients (15.5%) dying in May, 179 of 1,314 patients (13.6%) dying in June, 297 of 2,373 patients (12.5%) dying in July, and 174 of 1,361 (12.8%) patients dying in August (P<0.001).

Patients with Covid-19 who were treated in the ICUs during periods of increased Covid-19 ICU demand had increased risk of mortality compared to patients treated during periods of low Covid-19 ICU demand (i.e., demand of ≤25%).

Specifically:

  • The adjusted hazard ratio (HR) for all-cause mortality was 0.99 (95% CI, 0.81-1.22; P=0.93) among patients treated when Covid-19 ICU demand was more than 25% to 50%.
  • Adjusted HR was 1.19 (95% CI, 0.95-1.48; P=0.13) when Covid-19 ICU demand was more than 50% to 75%.
  • Adjusted HR was 1.94 (95% CI, 1.46-2.59; P<0.001) when Covid-19 ICU demand was more than 75% to 100%.

No association between Covid-19 ICU demand and mortality was seen for patients treated outside the ICU and the association between Covid-19 ICU load and mortality was not consistent over time (i.e., early vs late in the pandemic).

“Future research is urgently needed to investigate the mechanisms by which Covid-19 ICU demand may be associated with increased mortality; it is imperative that we 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 patients with critical Covid-19,” Bravata and colleagues wrote.

In commentary published with the study, Lewis Rubinson, MD, PhD, of Morristown Medical Center in Morristown, New Jersey, noted that the greatest ICU strain and mortality occurred in the early months of the pandemic.

“Because high levels of ICU load were not seen later in this study, the association with mortality may be partially or even entirely explained by secular trends in care,” Rubinson wrote. “Early in the pandemic, a number of unproven therapies were being used for potential antiviral effects or immunomodulation.”

Specifically, dexamethasone and emergency use authorization access to remdesivir occurred late in the study period, and there was less use of several potentially harmful treatments, such as hydroxychloroquine.

“Bravata et al presented important evidence that survival for patients with Covid-19 in the ICU may be associated with the number of other patients with Covid-19 who are concurrently in the same ICU,” Rubinson wrote. “If so, measures to flatten the curve and redistribute individuals with Covid-19 who are critically ill to other less impacted hospitals may be important strategies for improving survival.”

  1. Strains on demand and decreased intensive care unit (ICU) capacity in U.S. Veteran’s Affairs hospitals early in the Covid-19 pandemic were associated with higher death rates from the disease.
  2. Be aware that the high levels of ICU demand were not seen later in this study, and as the editorialists pointed out, “Early in the pandemic, a number of unproven therapies were being used for potential antiviral effects or immunomodulation.”

Salynn Boyles, Contributing Writer, BreakingMED™

This research was funded by the US Department of Veterans Affairs. Researchers Dawn Bravata and Anthony J. Perkins reported receiving grants from the Department of Veterans Affairs during the conduct of the study. Reseracher Rajiv Agarwal reported receiving personal fees and travel support from Bayer, Relypsa, Reata, Sanofi, Boehringer, and Merck; personal fees from Janssen, DiaMedica, Lexicon, Akebia, Eli Lilly, and Astra Zeneca; and travel support from Akebia outside the submitted work. Editorial writer Lewis Rubinson reportedserving on the advisory board for and owning nominal equity in Ventec Life Systems.

 

Cat ID: 926

Topic ID: 79,926,930,932,570,933,926,927,928,934