To evaluate the effectiveness of use of the bispectral index for monitoring of depth of sedation in ventilated patients during their prehospital management by a physician- staffed EMS. Hypothesis: there is a correlation between BIS and sedation scores.

The protocol compares BIS values to the RAMSAY score, which is the validated sedation scoring system in the prehospital setting.Ventilated patients receiving sedatives drugs can be included during primary prehospital interventions or interhospital transfers. During primary prehospital interventions, the protocol starts before endotracheal intubation. Depth of sedation is assessed every 5 minutes by the physician of EMS team. Blinded BIS monitoring is performed at the same time and recorded by the nurse at the end of out-of-hospital management. Data are analysed secondarily by the principal investigator.

Inclusion Criteria:

• Age >= 18
• Ventilated patient

Exclusion criteria:

• None

Out of hospital ventilated patients, managed by EMS, aged > 18