Major objective: a three-days interventional cross-over trial [one day music on, one day wash-out, one day music off][two periods of listening/day], to evaluate:

1. Impact on sedative drug consumption.
2. Alteration of stress neuropeptide blood concentrations.

Population: mechanically-ventilated ICU patients

The investigators hypothesize the music will decrease the need of sedative drugs and reduce the concentration of neuropeptides in circulation.

The study will imply patients mechanically ventilated for more than 3 days, that require sedation with benzodiazepine and narcotics.

There will be two groups both of exposed to music and placebo (headphones without music). The study will be simple blind.

Sedation scale will be followed regularly. Vitals signs and adjustment of sedation will be recorded by the nurse on the ward. Blood test will be taken before and after placement of headphones in the morning. We will measure IL-6, cortisol, copeptin, prolactin, CRP.

We will analyse the total reduction dose of sedation and analgesia on a daily basis. We will consider a fall of 20% of medication to be significative.

Inclusion Criteria:

• adults older than 18 years old
• expected time of mechanical ventilation of more than 72 hours
• sedation needs for a scale of Sedation-Agitation Scale (SAS) more than 1

Exclusion Criteria:

• hearing impairment
• pregnancy
• needs of vasopressin
• needs of curarisation