Non-invasive assessment of inspiratory efforts in acute hypoxemic respiratory failure – HIGH-EFFORT

Acute hypoxemic respiratory failure is a common cause of intensive care unit admission. In this setting, high-flow nasal oxygen is recommended as first-line oxygenation strategy to reduce the risk of intubation. However, high-flow nasal oxygen failure occurs in 30 to 50% of cases and is associated with high mortality.

Accumulating data suggest that the persistence of strong inspiratory efforts is associated with poor outcomes. In patients breathing through high-flow nasal oxygen or noninvasive ventilation, the persistence of strong inspiratory efforts is associated with increased risk of intubation and invasive ventilation. Additionally, in patients invasively ventilated, the persistence of strong inspiratory efforts is associated with increased discomfort, duration of invasive ventilation and intensive care unit stay, and mortality. However, the continuous noninvasive assessment of inspiratory efforts is not currently feasible. Therefore, it is not possible to detect early patients at increased risk of poor outcomes.

The overarching goal of this project is to develop tools assessing continuously inspiratory efforts to propose ultimately personalized interventions aiming at preventing intubation in patients under high-flow nasal oxygen, and at reducing discomfort, the duration of ventilation and intensive care unit stay, and mortality in patients invasively ventilated. The first aim is to deliver a prototype measuring continuously inspiratory efforts using esophageal pressure (for patients invasively ventilated). The second aim is to create two physiological signals databases containing simulated inspiratory efforts on bench, and inspiratory efforts measured in critically ill patients breathing through high-flow nasal oxygen to train an algorithm estimating continuously and noninvasively inspiratory efforts in patients under high-flow nasal oxygen. The third aim is to test the performance and to refine the algorithm on healthy volunteers breathing through high-flow nasal oxygen with strong inspiratory efforts.