Methoxyflurane hepatitis: two cases following obstetric analgesia

Area of Science:

• Anesthesiology and Perioperative Medicine
• Hepatology
• Obstetrics and Gynecology

Background:

• Methoxyflurane is an inhalation anesthetic agent used for analgesia during labor.
• Methoxyflurane is a known, albeit unpredictable, hepatotoxin.
• Hepatitis has been documented following methoxyflurane anesthesia, but rarely after its use for labor analgesia.

Observation:

• This report presents two additional cases of hepatitis occurring after methoxyflurane analgesia in labor.
• These cases add to the limited number of documented hepatic injuries associated with methoxyflurane for labor pain relief.

Findings:

• The findings suggest a potential risk of liver injury with methoxyflurane use, even at sub-anesthetic doses for labor analgesia.
• The exact mechanism remains unclear, but direct toxic effects of methoxyflurane metabolites are suspected.
• Host idiosyncrasy, or individual patient susceptibility, may also play a significant role in the development of hepatic injury.

Implications:

• These cases underscore the importance of vigilance for hepatotoxicity in patients receiving methoxyflurane for labor analgesia.
• Further research may be warranted to elucidate the mechanisms of methoxyflurane-induced liver injury and identify at-risk populations.
• Clinicians should consider the potential hepatotoxic risks when choosing analgesia options during labor.