Impact of the Experience of Anaesthetists in Changing Ventilation Strategies During Panendoscopy on the Incidence of Intraoperative Hypoxaemia

High Flow Nasal Oxygen Therapy (HFNO) is a new oxygenation tool that is becoming increasingly widespread in perioperative anaesthesia. The benefits of this oxygenation tool are based on different physiological principles. These include the reduction of dead space by "flushing" the nasopharyngeal cavities, positive airway pressure and the warming and humidification of inspired air. In addition, the high flow rates used ensure that the patient's inspiratory demand is covered, allowing for the delivery of oxygen-enriched and controlled air. It is simple to use, with the only parameters to be set being gas flow and FiO2. The use of HFNO appears to allow a prolongation of apnoea time without desaturation in apneic ventilation.Mainly studied in ENT surgery because of the interest that this oxygenation strategy presents with the absence of recourse to oro-tracheal intubation (OTI), several authors will use it in the framework of micro-laryngoscopy surgery in suspension. However, its use as an oxygenation strategy during panendoscopy has been little explored. Panendoscopy is a common procedure that requires deep and short anesthesia. The main challenge is the sharing of the airway between the anesthesia team and the surgical team. Learning to use this new method or the impact of operator experience has never been explored.

Inclusion Criteria:major patients receiving panendoscopyExclusion Criteria:panendoscopies performed in combination with another invasive procedure that may alter anaesthetic management