Methoxyflurane: a historical review and safety analysis of its use as an analgesic in emergency and outpatient procedures

Endoskopist, Obstetrician-gynecologist, Orthopaedic Trauma, Proctologist, Surgeon, Urologist
Methoxyflurane: a historical review and safety analysis of its use as an analgesic in emergency and outpatient procedures

Abstract. Methoxyflurane, introduced as an anesthetic agent in the 1960s, quickly gained popularity due to its potent properties. However, its use as an anesthetic was discontinued due to significant side effects, particularly nephrotoxicity, manifested as acute renal failure with high diuresis. By the mid-1970s, methoxyflurane was withdrawn from the anesthetic market in North America and gradually worldwide.

It was later discovered that low-dose methoxyflurane had powerful analgesic properties, allowing its use for short-term pain relief in traumatic injuries and during ambulatory procedures. Australian emergency services began using portable methoxyflurane inhalers for emergency care. Clinical trials confirmed the effectiveness of this agent, with no significant side effects such as renal or hepatic toxicity reported.

The physicochemical properties of methoxyflurane, particularly its high lipid solubility and low vapor pressure, provide a slow onset of sedation, limiting its sedative effects when used short-term.

Clinical studies have confirmed the safety and efficacy of methoxyflurane in conducting ambulatory procedures such as colonoscopy and burn wound dressing changes. Methoxyflurane reduces anxiety and pain, allowing patients to return to normal activities more quickly.

Thus, methoxyflurane, used as a low-dose inhaled analgesic, can be an effective and safe pain relief option during ambulatory medical and surgical procedures, particularly in patients at high risk of complications from traditional sedation methods. Further research, including large randomized controlled trials, may provide additional evidence to support the potential benefits of methoxyflurane.

Keywords: Methoxyflurane, analgesia, nephrotoxicity, ambulatory procedures.

Authors:

  • Dubrov Serhiy Oleksandrovych 1,2,3
  • Cherniaiev Stepan Volodymyrovych 2,3

1 Ministry of Health of Ukraine.
2 KNE “Kyiv City Clinical Hospital No. 17”.
3 O.O. Bogomolets National Medical University, Kyiv.

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5 November, 2024

Authors:

Cherniaiev Stepan Volodymyrovych Dubrov Serhiy Oleksandrovych

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