Impacts of a fraction of inspired oxygen adjustment protocol in COVID-19 patients under mechanical ventilation: A prospective cohort study
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Published on: May 4, 2021
E P Gomes1, M M Reboredo1, G B Costa2
1Pulmonary and Critical Care Division, University Hospital of Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil; School of Medicine, Federal University of Juiz de Fora, Juiz de Fora, Brazil.
Objective:
We examined weather a protocol for fraction of inspired oxygen (FiO2) adjustment can reduce hyperoxemia and excess oxygen use in COVID-19 patients mechanically ventilated.
Design:
Prospective cohort study.
Setting:
Two intensive care units (ICUs) dedicated to COVID-19 patients in Brazil.
Patients:
Consecutive patients with COVID-19 mechanically ventilated.
Interventions:
One ICU followed a FiO2 adjustment protocol based on SpO2 (conservative-oxygen ICU) and the other, which did not follow the protocol, constituted the control ICU.
Main Variables Of Interest:
Prevalence of hyperoxemia (PaO2>100mmHg) on day 1, sustained hyperoxemia (present on days 1 and 2), and excess oxygen use (FiO2>0.6 in patients with hyperoxemia) were compared between the two ICUs.
Results:
Eighty two patients from the conservative-oxygen ICU and 145 from the control ICU were included. The conservative-oxygen ICU presented lower prevalence of hyperoxemia on day 1 (40.2% vs. 75.9%, p<0.001) and of sustained hyperoxemia (12.2% vs. 49.6%, p<0.001). Excess oxygen use was less frequent in the conservative-oxygen ICU on day 1 (18.3% vs. 52.4%, p<0.001). Being admitted in the control ICU was independently associated with hyperoxemia and excess oxygen use. Multivariable analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FiO2 use and adverse clinical outcomes.
Conclusions:
Following FiO2 protocol was associated with lower hyperoxemia and less excess oxygen use. Although those results were not associated with better clinical outcomes, adopting FiO2 protocol may be useful in a scenario of depleted oxygen resources, as was seen during the COVID-19 pandemic.
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