In the Intensive Care Unit (ICU), scientific societies recommend starting enteral nutrition within 48 hours of admission, if oral nutrition is not available, in order to limit undernutrition. In patients who are sedated, have swallowing problems or cannot ensure adequate caloric intake, it is essential to insert a feeding tube, usually a nasogastric or orogastric tube for the first few weeks.

Placement of a naso- or oro-gastric tube in the intensive care unit is a frequent procedure, and considered to be straightforward. It is usually performed blindly, at the patient's bedside, by a nurse or doctor, according to a departmental protocol or the recommendations of learned societies.

Nevertheless, a number of complications have been reported with naso- or oro-gastric tubes, linked in particular to a route outside the digestive tract : malpositioning/coiling of the tube, epistaxis, sinusitis. The most frequent and potentially severe complications are malpositions in the tracheobronchial tree.

Radiographic control is currently considered in France and by certain learned societies to be the reference method for verifying correct positioning of the probe in the stomach (at the prepyloric antral level). However, thoracic radiography has a number of drawbacks : In intensive care risk of accidental displacement of other medical devices,irradiation, difficulty of interpretation, delay in obtaining the image, time-consuming work for qualified personnel.

An alternative technique using the NGPOD device is proposed as a method of checking the correct positioning of the probe in the stomach. This system enables immediate, rapid (15 seconds), simple and automatic testing at the patient's bedside. The device provides a visual indication of the pH detected at the tip of the gastric tube. The test result is given in binary form: Yes (green signal, probe in stomach) / No (red signal, probe incorrectly positioned).

Study hypothesis and prospects: To make an initial estimate of the sensitivity and specificity of the NGPOD system for checking the positioning of the naso- or oro-gastric tube in the stomach, compared with the recognized gold standard, the chest X-ray.

Inclusion Criteria:

• Patient hospitalized in intensive care
• Patients aged 18 or over with no upper age limit
• Patients admitted to intensive care with a nasogastric or orogastric tube placed in the operating room (not controlled by radiography) or for whom the placement of a gastric tube in intensive care is indicated.
• Consent to research participation

Exclusion Criteria:

• Patients undergoing limitation and discontinuation of active therapies
• Patients with contraindications to blind gastric tube placement (recent esophageal or gastric surgery, ENT lesions, uncontrolled upper GI bleeding, esophageal or gastric cancer)
• Patients under guardianship or curatorship
• Patient deprived of liberty
• Patient under court protection