Critical care patients experience systemic aggression, which may be the result of trauma, infection or other systemic inflammatory mechanisms. The initial phase of their illness is characterized by metabolic instability and increased catabolism. Nutrition goals in these patients are therefore, on the one hand, to provide sufficient caloric intake to cover energy expenditure while limiting the risks of inappropriate under-feeding, overfeeding- or re-feeding syndrome, and on the other hand, to meet the protein requirements linked to hypercatabolism. In the absence of contraindication, current recommandations state that an intensive care patient who cannot be fed orally, shoul receive continuous enteral nutrition over 24 hours by gastric tube within 48 hours of admission.

However, this 24-hour continuous nutrition method does not correspond to the physiological habit of the human species which includes a physiological nighttime fasting period.This fasting period induces a metabolic switch that regulates several pathways, including glycemic control, oxidative stressresistance and deoxyribonucleic acid (DNA) repair. Furthermore, it takes part un the synchronization of cellular circadian rhythms.

Investigator hypothetises that diurnal cyclic enteral nutrition may improve the prognosis of severe intensive care patients compared to continuous enteral nutrition.

Inclusion Criteria:

• Patient aged 18 years and over admitted to intensive care
• On invasive mechanical ventilation for less than 24 hours
• With an indication for exclusive enteral feeding by naso- or oro-gastric tube
• With an expected remaining duration of mechanical ventilation > 72 hours

Exclusion Criteria:

• Enteral feeding via tube already started
• Parenteral nutrition in progress or deemed necessary by the practitioner
• Active digestive haemorrhage as evidenced by fibroscopy or with need for transfusion
• Digestive surgery less than one month old
• History of mesenteric ischaemia
• History of gastrectomy, oesophagectomy, duodenopancreatectomy, bariatric surgery, short bowel syndrome
• Pregnant, lactating or parturient woman
• Body mass index < 18 kg/m2
• Person deprived of liberty by judicial or administrative decision, person under forced psychiatric care, person under legal protection (guardianship or curatorship)
• Lack of social security coverage
• Lack of consent or emergency procedure form
• Patient participating in another randomised clinical research study on feeding of resuscitation patients

Data will be shared upon reasonnable request from the principal investigator.