Low Dose Methoxyflurane and Out-Patient Aesthetic Surgery and Facial Filler

Inclusion Criteria: 1. Conscious adult patients: ≥ 18 years of age 2. Patient is scheduled for an outpatient anesthetic surgery (eg. hair transplant, upper blepharoplasty, otoplasty, upper brow lift, and mentoplasty) or a facial filler injection (eg. HA, and Sculptra®). 3. Patient should understand the nature of the study and provide written informed consent 4. Patient is able to follow all study requirements and procedures and complete required questionnaires Exclusion Criteria: 1. An altered level of consciousness, due to any cause, including head injury, drugs, or alcohol 2. Clinically significant renal impairment 3. Women of child bearing potential who are pregnant or peri partum, including labour 4. A history of liver dysfunction after previous methoxyflurane use or other halogenated anesthetics 5. Hypersensitivity to methoxyflurane or other halogenated anesthetics, or to butylated hydroxytoluene 6. Known or genetically susceptible to malignant hyperthermia or a history of severe adverse reactions in either patient or relatives 7. Clinically evident or potential hemodynamic instability as per the opinion of the investigator 8. Clinically evident respiratory impairment as per the opinion of the investigator 9. Prior treatment with PENTHROX® within 3 months