Reducing Hyperoxemia in Mechanically Ventilated Emergency Department Patients: A Before-and-After Study

Supplemental oxygen is a common therapy for emergency department (ED) patients undergoing invasive mechanical ventilation. Both hyperoxemia and hypoxemia carry potential risks. However, little is known about ideal oxygenation targets or ED based interventions.

To evaluate the effectiveness and safety of implementing an oxygen titration guideline to reduce hyperoxemia in mechanically ventilated ED patients.

We performed a single-center retrospective cohort study of mechanically ventilated ED patients pre- and postimplementation of a quality improvement (QI) intervention aimed at reducing hyperoxemia. The primary outcome was incidence of severe hyperoxemia (partial pressure of oxygen [PaO_2] > 300 mmHg), with safety outcomes including the incidences of hypoxemia (PaO₂ < 60 mmHg) and severe hypoxemia (PaO₂ < 50 mmHg). Additional secondary outcomes included in-hospital mortality, intensive care unit (ICU) length of stay, hospital length of stay, and median time on the ventilator.

The cohort included 1111 patients: 625 preintervention and 486 postintervention. The incidence of severe hyperoxemia decreased from 39.4% preintervention to 30% postintervention, adjusted odds ratio (aOR) 0.68, 95% confidence interval (CI), 0.51-0.91; p = 0.01. The incidence of hypoxemia increased from 7.5% to 13%, aOR 1.87, 95% CI, 1.22-2.88; p < 0.01, severe hypoxemia did not significantly change (3.4% preintervention and 3.1% postintervention). No significant differences were noted in ICU length of stay, hospital length of stay, or in-hospital mortality. Median time on the ventilator increased slightly postintervention.

Implementation of an oxygen titration guideline decreased severe hyperoxemia but increased hypoxemia, without affecting severe hypoxemia. Further research is needed to define ideal oxygenation targets and interventions to maintain patients within range.