Difficult / Failed Intubation

This prospective, multicenter observational study aims to evaluate the effect of different flow rates of high-flow nasal oxygen (HFNO) on the quality of the laryngoscopic view during videolaryngoscopy in adult patients undergoing general anesthesia. Each patient will serve as their own control, with repeated measurements obtained at three different HFNO flow settings (0, 40, and 60 L/min). The study will assess objective and subjective parameters of glottic visualization using standardized scoring systems.