Comparison of pre-oxygenation using spontaneous breathing through face mask and high-flow nasal oxygen: A randomised controlled crossover study in healthy volunteers
BACKGROUND
High-flow nasal oxygen (HFNO) therapy has been proposed for pre-oxygenation before intubation, but the end-tidal fraction of oxygen (ETO2) obtained remains unknown.
OBJECTIVE(S)
To compare the ETO2 following a 3 min pre-oxygenation with HFNO and face mask.
SETTING
Operating room in a primary university hospital.
DESIGN
A randomised crossover study.
PARTICIPANTS
Fifty healthy volunteers.
INTERVENTIONS
Participants were randomly pre-oxygenated through spontaneous breathing 100% oxygen in a face mask and with HFNO (mouth closed, heated and humidified gas flow at 60 l min–1). In the face mask group, the ETO2 was measured continuously. In the HFNO group, the nasal cannula was quickly exchanged with a face mask while the subject held their breath at end inspiration and the ETO2 was measured after a deep expiration. The protocol ended when ETO2 reached 90% or otherwise at 6 min.
MAIN OUTCOME MEASURES
The primary endpoint was the ETO2 after 3 min of pre-oxygenation. Secondary endpoints were the proportion of participants with an ETO2 at least 90% and the time until the ETO2 at least 90%.
RESULTS
The ETO2 after 3 min of pre-oxygenation was 89 (2) % and 77 (12) % in the face mask and HFNO groups [difference 12% (95% confidence interval, 95% CI: 8 to 15]; P
Source: European Journal of Anaesthesiology - Category: Anesthesiology Tags: Ventilation Source Type: research