Methoxyflurane vs Standard Analgesic Treatment for Trauma Pain in Spanish Emergency Units

Inclusion Criteria: * Adult patients: ≥ 18 years of age * Moderate to severe pain (NRS 0-10; \>=4) secondary to trauma * Without anticipating surgery due to the trauma, requiring hospitalization (hospital stay 12h) * Conscious patient. * Giving informed consent in writing Exclusion Criteria: * Hypersensitivity to methoxyflurane (MEOF) or any fluorinated anaesthetic. * Malignant hyperthermia: patients with known or genetically susceptible to malignant hyperthermia or a history of severe adverse reactions in either patient or relatives. * Patients who have a history of showing signs of liver damage after previous MEOF use or halogenated hydrocarbon anaesthesia * Known clinically significant renal impairment * Known pregnant or likely to be pregnant women at the time of inclusion. * Clinically evident cardiovascular instability * Clinically evident respiratory depression * Patients taken any analgesic for the traumatic pain before inclusion * Altered level of consciousness due to any cause, including head injury, drugs or alcohol * Degenerative diseases, mental illness or other conditions that could affect ability of valuing pain intensity * Patients to be unable to understand the purpose of the study and perform self-assessments, following investigator's criteria. * Participation in another clinical trial within 30 days prior to randomization