In patients with acute hypoxemic respiratory failure, preoxygenation is given before intubation. Non-invasive ventilation and high-flow nasal cannula oxygen therapy are both routinely used for preoxygenation, but their safety and efficacy have never been compared. This study aims to compare the efficacy and safety of non-invasive ventilation and high-flow nasal cannula oxygen therapy.

This open-label, multicenter trial included a total of 313 patients undergoing tracheal intubation for acute hypoxaemic respiratory failure. The patients were randomly assigned ina a 1:1 ratio to receive non-invasive ventilation (n=142) or high-flow oxygen during preoxygenation (n=171). The primary outcome of the study was the occurrence of severe hypoxemia during the treatment.

Severe hypoxemia was reported in 33 patients (23%) in the non-invasive ventilation group and 47 patients (27%) in the high-flow oxygen group. Among 242 patients with moderate-severe hypoxemia, severe hypoxemia occurred less frequently after preoxygenation with non-invasive ventilation (24%) than with high-flow oxygen (35%). Commonly occurring adverse events were similar in the two groups, with the most common events being systolic arterial hypotension and chest infiltrate. Death at day 28 occurred in 37% of patients in the non-invasive group and 34% in the high-oxygen group.

The research concluded that preoxygenation with non-invasive ventilation or high-flow oxygen therapy did not alleviate the risk of severe hypoxemia in patients with acute hypoxaemic respiratory failure.