Methoxyflurane in an inhaled anesthetic that has been studied as an analgesic in acute traumatic pain. What end-organ toxicity has been associated with prolonged and high-dose methoxyflurane use?
Methoxyflurane is an inhaled fluorinated anesthetic that is associated with polyuric renal failure secondary to the production of inorganic fluoride. In the United States, methoxyflurane was withdrawn from use by the FDA. Sevoflurane also undergoes biotransformation by defluorination but is not associated with clinically significant nephrotoxicity.
A randomized control trial in Spain recently investigated the use of methoxyflurane inhalants in acute traumatic pain.
Borobia AM, Collado SG, Cardona CC, Pueyo RC, Alonso CF, Torres IP, González MC, Casal Codesido JR, Betegón MA, Barcela LA, Andicoechea AO, Testa AF, Colina JT, Dorribo AC, Del Arco Galán C, Martínez Ávila JC, Lugilde ST, Carcas Sansuán AJ; InMEDIATE Investigators Group. Inhaled Methoxyflurane Provides Greater Analgesia and Faster Onset of Action Versus Standard Analgesia in Patients With Trauma Pain: InMEDIATE: A Randomized Controlled Trial in Emergency Departments. Ann Emerg Med. 2020 Mar;75(3):315-328. doi: 10.1016/j.annemergmed.2019.07.028. Epub 2019 Oct 14. PMID: 31623936.
Submitted by: Emily Kershner, MD on behalf of The Medical Toxicology Fellowship, Virginia Commonwealth University