Inclusion Criteria:  Patients must be admitted in an operative room, an intensive care unit (ICU) or an emergency department 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 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