This randomised study aims to compare the utilization of high-flow humidified nasal oxygenation (HFNO) with standard care, using apnoeic facemask oxygenation, during rapid sequence induction (RSI) of anesthesia in young children.

170 children aged less then 11 years, admitted to the operating room for surgery and with a medical indication of a RSI of anesthesia will be recruited in one university hospital (Necker-Enfants-Malades in Paris).

Children will be randomly assigned into two groups: the control group will benefit of standard care and the HFNO group will receive heated and humidified oxygen through a nasal cannula device during pre-oxygenation and apnoea time prior to tracheal intubation.

HFNO has been evaluated and showed benefits in rapid sequence induction of anesthesia in adults and prolonged apnea time before desaturation in children. To the investigators' knowledge the potential benefit of HFNO during RSI in young children remain to be evaluated.

Hypoxic events during rapid sequence induction (RSI) in children remain more frequent than during standard induction. Although the exact incidence is difficult to appreciate. However the deleterious consequences of hypoxemia during tracheal intubation procedures are well known.

HFNO is an effective technique to supplement oxygen including during apnoea. Studies in children have shown benefits both during breathing and apneic situation.

A monocentric controlled randomized study including children, aged less then 11 years, will be conducted in order to assess the potential benefits of this technique during RSI. The rate of successful tracheal intubation without oxygen desaturation is the primary outcome.

Children will be randomly assigned into two groups:

• The control group will benefit of standard RSI. Pre-oxygenation will be given through facemask with 100% oxygen during 2 minutes, with a flow of 6 to 8 L.min-1 depending on the age of the child. No oxygen will be delivered during laryngoscopy.
• The HFNO group will be given 2 L.Kg-1.min-1 of humidified and heated 100% O2 through a nasal cannula during a 2 minutes pre-oxygenation and then throughout laryngoscopy.

Adverse events will be recorded and follow-up continued until discharge from the post anesthesia care unit (PACU).

Inclusion Criteria:

• child from birth until 10 years
• patient needing (elective or in emergency) surgery under general anesthesia requiring tracheal intubation and fulfilling all criteria for a rapid sequence induction
• Parents or legal guardians signed the Informed consent form
• Social insurance affiliation

Exclusion Criteria

- child having one or more contraindication to use high flow nasal oxygenation:

• Nasal obstruction
• Recent trauma of aero-digestives tracts
• Epistaxis
• Known or suspected fracture of the skull base
• Cephalo-spinal fluid leak or all other communication between nasal space and intracranial space
• Tuberculosis or other nasal or lung infection
• Pneumothorax or pneumo-mediastin documented or suspected
• Complete limitation of mouth opening