Evaluation of the Safety of Inhaled Sedation With Isoflurane in Head Trauma Patients

"Inclusions will have 4 phases according to gradual increased doses of isoflurane:~Phase 1: Inclusion of 3 patients with 0.3 MAC isoflurane. In the absence of an increase of ICP \> 20% from baseline, inhaled sedation is maintained for 24 hours until the primary endpoint is assessed. If there one patient who does not tolerate this threshold, three additional patients will be included in this phase. A maximum of one treatment failure (see definition below) is tolerated in the phase 1~Phase 2: Inclusion of 3 additional patients with isoflurane dosage of 0.5 MAC under the same conditions as phase 1.~Phase 3: Inclusion of 3 additional patients with isoflurane dosage of 0.7 MAC under the same conditions as phases 1 and 2.~Phase 4: Inclusion of 12-15 additional patients will be included at the 0.7 MAC dose, to have 18 patients exposed to 0.7 MAC isoflurane."