Heavy sedation or sleep is a common problem within the intensive care unit (ICU) using our standard intravenous medications. This commonly leads to confusion, low blood pressure, slow wake up and removal of the artificial breathing tube (extubation), which prolongs ICU stay. Using inhaled volatile anesthetic agents are likely to improve these patient outcomes. This unique project is the first North American study looking at using volatiles for patients who need longer-term ICU sedation. This project has excellent potential at lowering these complications and improving quality of care, which will lower patient ICU stay and healthcare costs.

Inclusion Criteria:

• adult ICU patients expected to be ventilated > 48 hours

Exclusion Criteria:

• age < 18 years
• history of malignant hyperthermia
• propofol infusion syndrome
• evidence of raised intracranial pressure
• 6-month mortality risk from pre-existing condition > 50%
• lack of commitment to maximal treatment
• pregnant
• NebulizedFlolan
• tidal volume <350ml
• patients on one lung ventilation