Macintosh Blade Size for Endotracheal Intubation in Operative Rooms

Inclusion Criteria: * Patients must be admitted in a participating operative room and require mechanical ventilation through an orotracheal tube. * Adult (age ≥ 18 years) * Subjects must be covered by public health insurance * Written informed consent from the patient or proxy (if present) before inclusion or once possible when patient has been included in a context of emergency. Exclusion Criteria: * Anticipated difficult intubation requiring videolaryngoscopy or other technic in first place * Nasotracheal intubation * Refusal of study participation or to pursue the study by the patient * Absence of coverage by the French statutory healthcare insurance system * Protected person