Pressure ulcers represent a major health issue because of their high incidence and their important consequences. There is an important risk of pressure ulcer acquisition for ICU patients with acute organ failure(s).

Specific risk factors identified in ICU are immobility, which accentuates the effects of friction and shears, as well as mechanical ventilation and the use of vasopressors.

A repositioning schedule is a guideline for pressure ulcer prevention, but repositioning frequency remains unknown.

Adaptation of the repositioning schedule to pressure ulcer risk assessment using Braden scale should decrease the emergence of pressure ulcer. This could limit their important consequences for ICU patients which add to their brittle clinical condition (infection, increased length of stay, mortality…).

This is a multicenter randomized controlled cluster, parallel open study. In order to avoid a contamination bias between groups, this trial will be randomized at the center level. This randomization will lead to the formation of 2 groups: a group of control centers (usual care) and a group of interventional centers (repositioning schedule).

A visit to set up the study will be carried out before the beginning of the inclusions. During this visit, a training course will be delivered to the caregivers of all the research centers on the risk assessment of pressure ulcers using the Braden scale, the evaluation of the skin condition, the identification of the stages of pressure and their management as well as the collection of data necessary for this study. In addition, the interventional group centers will receive training on the application of the repositioning schedule.

The risk assessment for pressure ulcers using the Braden scale will be performed daily in both groups. All patients participating in research with a Braden scale ≤ 17 will benefit from a pressure ulcer prevention mattress.

Usual care:

Within the control group, repositioning schedule frequencies and positioning will be done according to the habits of the service. The daily collection form present in the room will collect information concerning the care related to the positioning of the patient (length of treatment, frequency of positioning, type of positioning, any adverse events occurring during this care), the evaluation of the patients 'cutaneous status, duration of pressure ulcer care and evaluation of the Braden scale. The possible contraindications to the positioning of the patients will be informed by the doctors on the medical prescription according to the current practice.

Repositioning schedule:

Within the interventional group the repositioning schedule will be applied according to the risk of pressure ulcer evaluated daily by the Braden scale. A medical prescription, as part of the care, will attest to the absence of absolute contraindication or relative to the procedure of mobilization.

Depending on the result of the Braden scale, the repositioning schedule is defined as follows:

6 ≥ Braden ≤ 8: alternate positioning every 2 hours; 9 ≥Braden ≤ 13: alternate positioning every 4 hours; 14 ≥ Braden ≤ 17: No alternative of the positioning required, but a friction and an evaluation of the cutaneous state every 6 hours.

18 ≥Braden ≤ 23: No alternative of the positioning required, but a friction and an evaluation of the cutaneous state every 12 hours

Inclusion Criteria:

• Age ≥ 18 years old without legal protection;
• Invasive or non-invasive mechanical ventilation;
• Inclusion in the first 48 hours following mechanical ventilation and in a maximum of 6 hours after 48 hours
• No pressure ulcer at the time of inclusion (according to EPUAP);
• Hospitalized in intensive care for less than 72 hours;
• Consent signed by the patient or in the event of the patient's temporary inability to express his or her wishes, consent will be obtained from a relative and signed by the patient as soon as possible; or in the absence of a relative, an emergency inclusion may be made; in this case a consent to proceed must be signed by the patient as soon as possible.

Exclusion Criteria:

• Patient admitted to intensive care unit for the multiple trauma management with spinal cord injury;
• Patient concerned by a medical decision to withhold/withdraw life sustaining therapies at the time of potential inclusion.
• Patient recruited in any other interventional research studying mobilization or positioning of the patient and/or pressure ulcer prevention and/or being in exclusion period of any other research if concerned;
• Patient already included once in the study
• Person without any health insurance scheme or not benefiting from a social security scheme