Which volatile anaesthetic agent undergoes the greatest degree of oxidative hepatic metabolism, accounting for its higher risk of immune-mediated hepatotoxicity?

• A Halothane, approximately 20 percent metabolised ✓
• B Enflurane, approximately 8 percent metabolised
• C Sevoflurane, approximately 5 percent metabolised
• D Isoflurane, approximately 2 percent metabolised

Explanation

Halothane is the most extensively metabolised volatile agent, with roughly 20 percent undergoing hepatic oxidative biotransformation via CYP2E1 to trifluoroacetylated protein adducts that trigger halothane hepatitis. Enflurane is about 2 to 8 percent metabolised, sevoflurane 3 to 5 percent, isoflurane about 0.2 percent and desflurane only 0.02 percent. The extent of metabolism correlates directly with the risk of fulminant hepatic necrosis after repeated exposure.

Reference: Miller's Anesthesia, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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