Upper aerodigestive tract endoscopy is routinely performed for the diagnosis and staging of head and neck cancers. These procedures are commonly conducted under general anaesthesia with spontaneous ventilation to optimise surgical exposure and avoid tracheal intubation. However, maintaining adequate oxygenation remains challenging, particularly in patients with altered airway anatomy due to prior surgery or radiotherapy.

Standard practice often involves a preliminary laryngoscopy to insert a nasopharyngeal oxygen catheter, which may increase procedural complexity and interfere with surgical conditions. High-flow nasal oxygen (HFNO) has emerged as a promising alternative for maintaining oxygenation in various perioperative settings.

The OPTIGO trial aims to determine whether HFNO is non-inferior to nasopharyngeal oxygen insufflation in preventing intraoperative oxygen desaturation during upper aerodigestive tract endoscopy.

The OPTIGO study is a multicentre, prospective, randomised, open-label, non-inferiority trial conducted in three French centres. A total of 610 adult patients scheduled for endoscopic procedures of the pharynx, larynx and oesophagus will be randomised in a 1:1 ratio to receive either HFNO or standard oxygenation via a nasopharyngeal oxygen catheter.

The primary outcome is the occurrence of intraoperative oxygen desaturation, defined as a peripheral oxygen saturation ≤85% at any time from induction to the end of the procedure.

Secondary outcomes include intraoperative complications, postoperative laryngeal pain, surgeon comfort, duration of the procedure, anaesthetic drug consumption, and perioperative gas exchange.

This study has been approved by the independent ethics committee CPP Est 1 (10 April 2025; EudraCT 2025-A00278-41). The trial will be conducted in accordance with the Declaration of Helsinki and Good Clinical Practice Guidelines.

Results will be disseminated through presentations at scientific conferences and publication in peer-reviewed journals.

CPP Est 1 EudraCT 2025-A00278-41 (Clinical trial NCT07004699).