Impact of Nasal High-flow vs Venturi Mask Oxygen Therapy on Weaning Outcome: a Multicenter, Randomized, Controlled Trial

This study compares the effects of two devices for oxygen therapy, the nasal, high-flow (Optiflow, intervention) and the Venturi mask (control), on the outcome of extubation. Available data suggest that Optiflow can improve oxygenation and patient's comfort in critically ill patients after extubation. The study hypothesis is that Optiflow may reduce the extubation failure rate in these patients.

In the intervention group, patients fulfilling inclusion criteria and not presenting any of the exclusion criteria will receive high-flow oxygen through nasal cannula (Optiflow, Fisher & Paykel Healthcare Ltd., New Zealand) after extubation. The oxygen concentration (FiO2) will be set to reach an oxygenation target similar to control patients (see below), while the gas flow rate will be set at 50 L/min.

In the control group, patients fulfilling inclusion criteria and not presenting any of the exclusion criteria will receive oxygen through a standard Venturi mask after extubation. The FiO2 will be set to obtain a arterial oxygen saturation (SpO2) between 92% and 98% (or between 88% and 95% in hypercapnic patients). Further FiO2 modifications will be performed by the attending physicians to meet the oxygenation target.

Inclusion criteria

• Age ≥ 18 years
• Mechanical ventilation > 24 hours
• Signed Informed Consent
• Successful spontaneous breathing trial
• PaO2/FiO2 ratio ≤ 300 (or SpO2/FiO2 ratio ≤ 300 if SpO2 is lower than 98%) within 30 min after extubation while breathing through a Venturi mask with a delivered FiO2 of 31%

Exclusion criteria

• Pregnancy
• Presence of tracheostomy
• Need for immediate post-extubation Non-Invasive Ventilation (>3 consecutive failures of the spontaneous breathing trial and/or a PaCO2 > 45 mmHg before the spontaneous breathing trial, with a respiratory rate ≥ 25/min)