Oro-tracheal intubation is performed daily in anesthesia and in the ICU. When a patient is intubated, the endotracheal tube must be inserted into the trachea to the right depth. If the tube is not deep Inserted enough there is a risk of accidental extubation and trauma to the vocal cords by the balloon. If the tube is inserted too far there is a risk of selective intubation into the right or left mainstem bronchus, which can lead to contralateral lung atelectasis and hypoxemia.

The purpose of this study is to determine whether there is a correlation between the measurement of the airway of an adult population and criteria that would be easily accessible in daily clinical practice: the height of the patient and the size of their feet.

Inclusion Criteria:

• patient scheduled for a CT-scan including the airways and the upper part of the chest at least until the carina
• patient size between between 150 cm and 195 cm

Exclusion Criteria:

• significant deformity of the cervical spine to accurately measure the size of patients (kyphoscoliosis...)
• impossibility of reliably know the size of the patient
• history of pharyngo-laryngeal surgery resulting in a significant deformity or a loss of anatomical landmarks incompatible with reliable measurements between dental arches and glottic plan (total laryngectomy...)
• history of lung surgery not allowing reliable location of the carina (pneumonectomy, double-lung transplant)

Patient scheduled for a CT-scan including the airways and the upper part of the chest until the hull